X-Git-Url: https://git.pterodactylus.net/?a=blobdiff_plain;f=libs%2Fsqlite3%2Fsqlite3.c;h=08a468fb65fcc6772486169d2fa3f8a2000ccc67;hb=d5c9f7e6c1dd263dfc85a3cb5941a378a5ddd923;hp=c8460579dfb49cac07b63cb121a21fc9fac66e8b;hpb=1dee4e3cd008a27789bbce05b0eb47b0eb5d121a;p=fms.git diff --git a/libs/sqlite3/sqlite3.c b/libs/sqlite3/sqlite3.c index c846057..08a468f 100644 --- a/libs/sqlite3/sqlite3.c +++ b/libs/sqlite3/sqlite3.c @@ -1,6 +1,6 @@ /****************************************************************************** ** This file is an amalgamation of many separate C source files from SQLite -** version 3.5.7. By combining all the individual C code files into this +** version 3.6.4. By combining all the individual C code files into this ** single large file, the entire code can be compiled as a one translation ** unit. This allows many compilers to do optimizations that would not be ** possible if the files were compiled separately. Performance improvements @@ -11,13 +11,13 @@ ** programs, you need this file and the "sqlite3.h" header file that defines ** the programming interface to the SQLite library. (If you do not have ** the "sqlite3.h" header file at hand, you will find a copy in the first -** 5413 lines past this header comment.) Additional code files may be +** 6527 lines past this header comment.) Additional code files may be ** needed if you want a wrapper to interface SQLite with your choice of ** programming language. The code for the "sqlite3" command-line shell ** is also in a separate file. This file contains only code for the core ** SQLite library. ** -** This amalgamation was generated on 2008-03-17 18:47:08 UTC. +** This amalgamation was generated on 2008-10-15 11:26:48 UTC. */ #define SQLITE_CORE 1 #define SQLITE_AMALGAMATION 1 @@ -41,111 +41,19 @@ ************************************************************************* ** Internal interface definitions for SQLite. ** -** @(#) $Id: sqliteInt.h,v 1.673 2008/03/14 13:02:08 mlcreech Exp $ +** @(#) $Id: sqliteInt.h,v 1.784 2008/10/13 15:35:09 drh Exp $ */ #ifndef _SQLITEINT_H_ #define _SQLITEINT_H_ /* -** Include the configuration header output by 'configure' if it was run -** (otherwise we get an empty default). +** Include the configuration header output by 'configure' if we're using the +** autoconf-based build */ -/************** Include config.h in the middle of sqliteInt.h ****************/ -/************** Begin file config.h ******************************************/ -/* -** 2008 March 6 -** -** The author disclaims copyright to this source code. In place of -** a legal notice, here is a blessing: -** -** May you do good and not evil. -** May you find forgiveness for yourself and forgive others. -** May you share freely, never taking more than you give. -** -************************************************************************* -** Default configuration header in case the 'configure' script is not used -** -** @(#) $Id: config.h,v 1.1 2008/03/06 07:36:18 mlcreech Exp $ -*/ -#ifndef _CONFIG_H_ -#define _CONFIG_H_ - -/* We do nothing here, since no assumptions are made by default */ - -#endif - -/************** End of config.h **********************************************/ -/************** Continuing where we left off in sqliteInt.h ******************/ - -/* Needed for various definitions... */ -#define _GNU_SOURCE - -/* -** Include standard header files as necessary -*/ -#ifdef HAVE_STDINT_H -#include -#endif -#ifdef HAVE_INTTYPES_H -#include -#endif - -/* -** If possible, use the C99 intptr_t type to define an integral type of -** equivalent size to a pointer. (Technically it's >= sizeof(void *), but -** practically it's == sizeof(void *)). We fall back to an int if this type -** isn't defined. -*/ -#ifdef HAVE_INTPTR_T - typedef intptr_t sqlite3_intptr_t; -#else - typedef int sqlite3_intptr_t; +#ifdef _HAVE_SQLITE_CONFIG_H +#include "config.h" #endif - -/* -** The macro unlikely() is a hint that surrounds a boolean -** expression that is usually false. Macro likely() surrounds -** a boolean expression that is usually true. GCC is able to -** use these hints to generate better code, sometimes. -*/ -#if defined(__GNUC__) && 0 -# define likely(X) __builtin_expect((X),1) -# define unlikely(X) __builtin_expect((X),0) -#else -# define likely(X) !!(X) -# define unlikely(X) !!(X) -#endif - - -/* -** These #defines should enable >2GB file support on Posix if the -** underlying operating system supports it. If the OS lacks -** large file support, or if the OS is windows, these should be no-ops. -** -** Ticket #2739: The _LARGEFILE_SOURCE macro must appear before any -** system #includes. Hence, this block of code must be the very first -** code in all source files. -** -** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch -** on the compiler command line. This is necessary if you are compiling -** on a recent machine (ex: RedHat 7.2) but you want your code to work -** on an older machine (ex: RedHat 6.0). If you compile on RedHat 7.2 -** without this option, LFS is enable. But LFS does not exist in the kernel -** in RedHat 6.0, so the code won't work. Hence, for maximum binary -** portability you should omit LFS. -** -** Similar is true for MacOS. LFS is only supported on MacOS 9 and later. -*/ -#ifndef SQLITE_DISABLE_LFS -# define _LARGE_FILE 1 -# ifndef _FILE_OFFSET_BITS -# define _FILE_OFFSET_BITS 64 -# endif -# define _LARGEFILE_SOURCE 1 -#endif - - /************** Include sqliteLimit.h in the middle of sqliteInt.h ***********/ /************** Begin file sqliteLimit.h *************************************/ /* @@ -162,7 +70,7 @@ ** ** This file defines various limits of what SQLite can process. ** -** @(#) $Id: sqliteLimit.h,v 1.6 2007/12/17 16:20:07 drh Exp $ +** @(#) $Id: sqliteLimit.h,v 1.8 2008/03/26 15:56:22 drh Exp $ */ /* @@ -199,18 +107,24 @@ /* ** The maximum length of a single SQL statement in bytes. -** A value of zero means there is no limit. +** +** It used to be the case that setting this value to zero would +** turn the limit off. That is no longer true. It is not possible +** to turn this limit off. */ #ifndef SQLITE_MAX_SQL_LENGTH -# define SQLITE_MAX_SQL_LENGTH 0 +# define SQLITE_MAX_SQL_LENGTH 1000000000 #endif /* ** The maximum depth of an expression tree. This is limited to ** some extent by SQLITE_MAX_SQL_LENGTH. But sometime you might ** want to place more severe limits on the complexity of an -** expression. A value of 0 (the default) means do not enforce -** any limitation on expression tree depth. +** expression. +** +** A value of 0 used to mean that the limit was not enforced. +** But that is no longer true. The limit is now strictly enforced +** at all times. */ #ifndef SQLITE_MAX_EXPR_DEPTH # define SQLITE_MAX_EXPR_DEPTH 1000 @@ -255,11 +169,9 @@ #endif /* -** The maximum number of attached databases. This must be at least 2 -** in order to support the main database file (0) and the file used to -** hold temporary tables (1). And it must be less than 32 because -** we use a bitmask of databases with a u32 in places (for example -** the Parse.cookieMask field). +** The maximum number of attached databases. This must be between 0 +** and 30. The upper bound on 30 is because a 32-bit integer bitmap +** is used internally to track attached databases. */ #ifndef SQLITE_MAX_ATTACHED # define SQLITE_MAX_ATTACHED 10 @@ -331,46 +243,121 @@ /************** End of sqliteLimit.h *****************************************/ /************** Continuing where we left off in sqliteInt.h ******************/ +/* Disable nuisance warnings on Borland compilers */ +#if defined(__BORLANDC__) +#pragma warn -rch /* unreachable code */ +#pragma warn -ccc /* Condition is always true or false */ +#pragma warn -aus /* Assigned value is never used */ +#pragma warn -csu /* Comparing signed and unsigned */ +#pragma warn -spa /* Suspicous pointer arithmetic */ +#endif + +/* Needed for various definitions... */ +#ifndef _GNU_SOURCE +# define _GNU_SOURCE +#endif + /* -** For testing purposes, the various size limit constants are really -** variables that we can modify in the testfixture. +** Include standard header files as necessary */ -#ifdef SQLITE_TEST - #undef SQLITE_MAX_LENGTH - #undef SQLITE_MAX_COLUMN - #undef SQLITE_MAX_SQL_LENGTH - #undef SQLITE_MAX_EXPR_DEPTH - #undef SQLITE_MAX_COMPOUND_SELECT - #undef SQLITE_MAX_VDBE_OP - #undef SQLITE_MAX_FUNCTION_ARG - #undef SQLITE_MAX_VARIABLE_NUMBER - #undef SQLITE_MAX_PAGE_SIZE - #undef SQLITE_MAX_PAGE_COUNT - #undef SQLITE_MAX_LIKE_PATTERN_LENGTH - - #define SQLITE_MAX_LENGTH sqlite3MAX_LENGTH - #define SQLITE_MAX_COLUMN sqlite3MAX_COLUMN - #define SQLITE_MAX_SQL_LENGTH sqlite3MAX_SQL_LENGTH - #define SQLITE_MAX_EXPR_DEPTH sqlite3MAX_EXPR_DEPTH - #define SQLITE_MAX_COMPOUND_SELECT sqlite3MAX_COMPOUND_SELECT - #define SQLITE_MAX_VDBE_OP sqlite3MAX_VDBE_OP - #define SQLITE_MAX_FUNCTION_ARG sqlite3MAX_FUNCTION_ARG - #define SQLITE_MAX_VARIABLE_NUMBER sqlite3MAX_VARIABLE_NUMBER - #define SQLITE_MAX_PAGE_SIZE sqlite3MAX_PAGE_SIZE - #define SQLITE_MAX_PAGE_COUNT sqlite3MAX_PAGE_COUNT - #define SQLITE_MAX_LIKE_PATTERN_LENGTH sqlite3MAX_LIKE_PATTERN_LENGTH - - extern int sqlite3MAX_LENGTH; - extern int sqlite3MAX_COLUMN; - extern int sqlite3MAX_SQL_LENGTH; - extern int sqlite3MAX_EXPR_DEPTH; - extern int sqlite3MAX_COMPOUND_SELECT; - extern int sqlite3MAX_VDBE_OP; - extern int sqlite3MAX_FUNCTION_ARG; - extern int sqlite3MAX_VARIABLE_NUMBER; - extern int sqlite3MAX_PAGE_SIZE; - extern int sqlite3MAX_PAGE_COUNT; - extern int sqlite3MAX_LIKE_PATTERN_LENGTH; +#ifdef HAVE_STDINT_H +#include +#endif +#ifdef HAVE_INTTYPES_H +#include +#endif + +/* +** A macro used to aid in coverage testing. When doing coverage +** testing, the condition inside the argument must be evaluated +** both true and false in order to get full branch coverage. +** This macro can be inserted to ensure adequate test coverage +** in places where simple condition/decision coverage is inadequate. +*/ +#ifdef SQLITE_COVERAGE_TEST +SQLITE_PRIVATE void sqlite3Coverage(int); +# define testcase(X) if( X ){ sqlite3Coverage(__LINE__); } +#else +# define testcase(X) +#endif + +/* +** The ALWAYS and NEVER macros surround boolean expressions which +** are intended to always be true or false, respectively. Such +** expressions could be omitted from the code completely. But they +** are included in a few cases in order to enhance the resilience +** of SQLite to unexpected behavior - to make the code "self-healing" +** or "ductile" rather than being "brittle" and crashing at the first +** hint of unplanned behavior. +** +** When doing coverage testing ALWAYS and NEVER are hard-coded to +** be true and false so that the unreachable code then specify will +** not be counted as untested code. +*/ +#ifdef SQLITE_COVERAGE_TEST +# define ALWAYS(X) (1) +# define NEVER(X) (0) +#else +# define ALWAYS(X) (X) +# define NEVER(X) (X) +#endif + +/* +** The macro unlikely() is a hint that surrounds a boolean +** expression that is usually false. Macro likely() surrounds +** a boolean expression that is usually true. GCC is able to +** use these hints to generate better code, sometimes. +*/ +#if defined(__GNUC__) && 0 +# define likely(X) __builtin_expect((X),1) +# define unlikely(X) __builtin_expect((X),0) +#else +# define likely(X) !!(X) +# define unlikely(X) !!(X) +#endif + +/* + * This macro is used to "hide" some ugliness in casting an int + * value to a ptr value under the MSVC 64-bit compiler. Casting + * non 64-bit values to ptr types results in a "hard" error with + * the MSVC 64-bit compiler which this attempts to avoid. + * + * A simple compiler pragma or casting sequence could not be found + * to correct this in all situations, so this macro was introduced. + * + * It could be argued that the intptr_t type could be used in this + * case, but that type is not available on all compilers, or + * requires the #include of specific headers which differs between + * platforms. + */ +#define SQLITE_INT_TO_PTR(X) ((void*)&((char*)0)[X]) +#define SQLITE_PTR_TO_INT(X) ((int)(((char*)X)-(char*)0)) + +/* +** These #defines should enable >2GB file support on Posix if the +** underlying operating system supports it. If the OS lacks +** large file support, or if the OS is windows, these should be no-ops. +** +** Ticket #2739: The _LARGEFILE_SOURCE macro must appear before any +** system #includes. Hence, this block of code must be the very first +** code in all source files. +** +** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch +** on the compiler command line. This is necessary if you are compiling +** on a recent machine (ex: RedHat 7.2) but you want your code to work +** on an older machine (ex: RedHat 6.0). If you compile on RedHat 7.2 +** without this option, LFS is enable. But LFS does not exist in the kernel +** in RedHat 6.0, so the code won't work. Hence, for maximum binary +** portability you should omit LFS. +** +** Similar is true for MacOS. LFS is only supported on MacOS 9 and later. +*/ +#ifndef SQLITE_DISABLE_LFS +# define _LARGE_FILE 1 +# ifndef _FILE_OFFSET_BITS +# define _FILE_OFFSET_BITS 64 +# endif +# define _LARGEFILE_SOURCE 1 #endif @@ -388,6 +375,16 @@ #endif /* +** The SQLITE_DEFAULT_MEMSTATUS macro must be defined as either 0 or 1. +** It determines whether or not the features related to +** SQLITE_CONFIG_MEMSTATUS are availabe by default or not. This value can +** be overridden at runtime using the sqlite3_config() API. +*/ +#if !defined(SQLITE_DEFAULT_MEMSTATUS) +# define SQLITE_DEFAULT_MEMSTATUS 1 +#endif + +/* ** Exactly one of the following macros must be defined in order to ** specify which memory allocation subsystem to use. ** @@ -438,6 +435,9 @@ # define _XOPEN_SOURCE 500 /* Needed to enable pthread recursive mutexes */ #endif +/* +** The TCL headers are only needed when compiling the TCL bindings. +*/ #if defined(SQLITE_TCL) || defined(TCLSH) # include #endif @@ -474,7 +474,7 @@ ** ** Some of the definitions that are in this file are marked as ** "experimental". Experimental interfaces are normally new -** features recently added to SQLite. We do not anticipate changes +** features recently added to SQLite. We do not anticipate changes ** to experimental interfaces but reserve to make minor changes if ** experience from use "in the wild" suggest such changes are prudent. ** @@ -487,7 +487,7 @@ ** the version number) and changes its name to "sqlite3.h" as ** part of the build process. ** -** @(#) $Id: sqlite.h.in,v 1.291 2008/03/08 12:37:31 drh Exp $ +** @(#) $Id: sqlite.h.in,v 1.404 2008/10/12 00:27:54 shane Exp $ */ #ifndef _SQLITE3_H_ #define _SQLITE3_H_ @@ -509,8 +509,23 @@ extern "C" { #endif /* -** Make sure these symbols where not defined by some previous header -** file. +** These no-op macros are used in front of interfaces to mark those +** interfaces as either deprecated or experimental. New applications +** should not use deprecated intrfaces - they are support for backwards +** compatibility only. Application writers should be aware that +** experimental interfaces are subject to change in point releases. +** +** These macros used to resolve to various kinds of compiler magic that +** would generate warning messages when they were used. But that +** compiler magic ended up generating such a flurry of bug reports +** that we have taken it all out and gone back to using simple +** noop macros. +*/ +#define SQLITE_DEPRECATED +#define SQLITE_EXPERIMENTAL + +/* +** Ensure these symbols were not defined by some previous header file. */ #ifdef SQLITE_VERSION # undef SQLITE_VERSION @@ -520,7 +535,7 @@ extern "C" { #endif /* -** CAPI3REF: Compile-Time Library Version Numbers {F10010} +** CAPI3REF: Compile-Time Library Version Numbers {H10010} ** ** The SQLITE_VERSION and SQLITE_VERSION_NUMBER #defines in ** the sqlite3.h file specify the version of SQLite with which @@ -529,39 +544,38 @@ extern "C" { ** The "version" of SQLite is a string of the form "X.Y.Z". ** The phrase "alpha" or "beta" might be appended after the Z. ** The X value is major version number always 3 in SQLite3. -** The X value only changes when backwards compatibility is -** broken and we intend to never break -** backwards compatibility. The Y value is the minor version -** number and only changes when +** The X value only changes when backwards compatibility is +** broken and we intend to never break backwards compatibility. +** The Y value is the minor version number and only changes when ** there are major feature enhancements that are forwards compatible -** but not backwards compatible. The Z value is release number -** and is incremented with -** each release but resets back to 0 when Y is incremented. +** but not backwards compatible. +** The Z value is the release number and is incremented with +** each release but resets back to 0 whenever Y is incremented. ** ** See also: [sqlite3_libversion()] and [sqlite3_libversion_number()]. ** ** INVARIANTS: ** -** {F10011} The SQLITE_VERSION #define in the sqlite3.h header file -** evaluates to a string literal that is the SQLite version +** {H10011} The SQLITE_VERSION #define in the sqlite3.h header file shall +** evaluate to a string literal that is the SQLite version ** with which the header file is associated. ** -** {F10014} The SQLITE_VERSION_NUMBER #define resolves to an integer -** with the value (X*1000000 + Y*1000 + Z) where X, Y, and -** Z are the major version, minor version, and release number. +** {H10014} The SQLITE_VERSION_NUMBER #define shall resolve to an integer +** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z +** are the major version, minor version, and release number. */ -#define SQLITE_VERSION "3.5.7" -#define SQLITE_VERSION_NUMBER 3005007 +#define SQLITE_VERSION "3.6.4" +#define SQLITE_VERSION_NUMBER 3006004 /* -** CAPI3REF: Run-Time Library Version Numbers {F10020} +** CAPI3REF: Run-Time Library Version Numbers {H10020} ** KEYWORDS: sqlite3_version ** ** These features provide the same information as the [SQLITE_VERSION] ** and [SQLITE_VERSION_NUMBER] #defines in the header, but are associated ** with the library instead of the header file. Cautious programmers might -** include a check in their application to verify that -** sqlite3_libversion_number() always returns the value +** include a check in their application to verify that +** sqlite3_libversion_number() always returns the value ** [SQLITE_VERSION_NUMBER]. ** ** The sqlite3_libversion() function returns the same information as is @@ -571,13 +585,13 @@ extern "C" { ** ** INVARIANTS: ** -** {F10021} The [sqlite3_libversion_number()] interface returns an integer -** equal to [SQLITE_VERSION_NUMBER]. +** {H10021} The [sqlite3_libversion_number()] interface shall return +** an integer equal to [SQLITE_VERSION_NUMBER]. ** -** {F10022} The [sqlite3_version] string constant contains the text of the -** [SQLITE_VERSION] string. +** {H10022} The [sqlite3_version] string constant shall contain +** the text of the [SQLITE_VERSION] string. ** -** {F10023} The [sqlite3_libversion()] function returns +** {H10023} The [sqlite3_libversion()] function shall return ** a pointer to the [sqlite3_version] string constant. */ SQLITE_API const char sqlite3_version[]; @@ -585,64 +599,77 @@ SQLITE_API const char *sqlite3_libversion(void); SQLITE_API int sqlite3_libversion_number(void); /* -** CAPI3REF: Test To See If The Library Is Threadsafe {F10100} +** CAPI3REF: Test To See If The Library Is Threadsafe {H10100} ** ** SQLite can be compiled with or without mutexes. When -** the SQLITE_THREADSAFE C preprocessor macro is true, mutexes -** are enabled and SQLite is threadsafe. When that macro is false, +** the [SQLITE_THREADSAFE] C preprocessor macro 1 or 2, mutexes +** are enabled and SQLite is threadsafe. When the +** [SQLITE_THREADSAFE] macro is 0, ** the mutexes are omitted. Without the mutexes, it is not safe -** to use SQLite from more than one thread. +** to use SQLite concurrently from more than one thread. ** -** There is a measurable performance penalty for enabling mutexes. +** Enabling mutexes incurs a measurable performance penalty. ** So if speed is of utmost importance, it makes sense to disable ** the mutexes. But for maximum safety, mutexes should be enabled. ** The default behavior is for mutexes to be enabled. ** ** This interface can be used by a program to make sure that the ** version of SQLite that it is linking against was compiled with -** the desired setting of the SQLITE_THREADSAFE macro. +** the desired setting of the [SQLITE_THREADSAFE] macro. +** +** This interface only reports on the compile-time mutex setting +** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with +** SQLITE_THREADSAFE=1 then mutexes are enabled by default but +** can be fully or partially disabled using a call to [sqlite3_config()] +** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], +** or [SQLITE_CONFIG_MUTEX]. The return value of this function shows +** only the default compile-time setting, not any run-time changes +** to that setting. +** +** See the [threading mode] documentation for additional information. ** ** INVARIANTS: ** -** {F10101} The [sqlite3_threadsafe()] function returns nonzero if -** SQLite was compiled with its mutexes enabled or zero -** if SQLite was compiled with mutexes disabled. +** {H10101} The [sqlite3_threadsafe()] function shall return zero if +** and only if SQLite was compiled with mutexing code omitted. +** +** {H10102} The value returned by the [sqlite3_threadsafe()] function +** shall remain the same across calls to [sqlite3_config()]. */ SQLITE_API int sqlite3_threadsafe(void); /* -** CAPI3REF: Database Connection Handle {F12000} -** KEYWORDS: {database connection} +** CAPI3REF: Database Connection Handle {H12000} +** KEYWORDS: {database connection} {database connections} ** -** Each open SQLite database is represented by pointer to an instance of the -** opaque structure named "sqlite3". It is useful to think of an sqlite3 +** Each open SQLite database is represented by a pointer to an instance of +** the opaque structure named "sqlite3". It is useful to think of an sqlite3 ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and -** [sqlite3_open_v2()] interfaces are its constructors -** and [sqlite3_close()] is its destructor. There are many other interfaces -** (such as [sqlite3_prepare_v2()], [sqlite3_create_function()], and -** [sqlite3_busy_timeout()] to name but three) that are methods on this -** object. +** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] +** is its destructor. There are many other interfaces (such as +** [sqlite3_prepare_v2()], [sqlite3_create_function()], and +** [sqlite3_busy_timeout()] to name but three) that are methods on an +** sqlite3 object. */ typedef struct sqlite3 sqlite3; - /* -** CAPI3REF: 64-Bit Integer Types {F10200} +** CAPI3REF: 64-Bit Integer Types {H10200} ** KEYWORDS: sqlite_int64 sqlite_uint64 ** ** Because there is no cross-platform way to specify 64-bit integer types ** SQLite includes typedefs for 64-bit signed and unsigned integers. ** -** The sqlite3_int64 and sqlite3_uint64 are the preferred type -** definitions. The sqlite_int64 and sqlite_uint64 types are -** supported for backwards compatibility only. +** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. +** The sqlite_int64 and sqlite_uint64 types are supported for backwards +** compatibility only. ** ** INVARIANTS: ** -** {F10201} The [sqlite_int64] and [sqlite3_int64] types specify a -** 64-bit signed integer. +** {H10201} The [sqlite_int64] and [sqlite3_int64] type shall specify +** a 64-bit signed integer. ** -** {F10202} The [sqlite_uint64] and [sqlite3_uint64] types specify +** {H10202} The [sqlite_uint64] and [sqlite3_uint64] type shall specify ** a 64-bit unsigned integer. */ #ifdef SQLITE_INT64_TYPE @@ -660,50 +687,62 @@ typedef sqlite_uint64 sqlite3_uint64; /* ** If compiling for a processor that lacks floating point support, -** substitute integer for floating-point +** substitute integer for floating-point. */ #ifdef SQLITE_OMIT_FLOATING_POINT # define double sqlite3_int64 #endif /* -** CAPI3REF: Closing A Database Connection {F12010} +** CAPI3REF: Closing A Database Connection {H12010} ** -** This routine is the destructor for the [sqlite3] object. +** This routine is the destructor for the [sqlite3] object. ** -** Applications should [sqlite3_finalize | finalize] all -** [prepared statements] and -** [sqlite3_blob_close | close] all [sqlite3_blob | BLOBs] -** associated with the [sqlite3] object prior -** to attempting to close the [sqlite3] object. +** Applications should [sqlite3_finalize | finalize] all [prepared statements] +** and [sqlite3_blob_close | close] all [BLOB handles] associated with +** the [sqlite3] object prior to attempting to close the object. +** The [sqlite3_next_stmt()] interface can be used to locate all +** [prepared statements] associated with a [database connection] if desired. +** Typical code might look like this: +** +** 
+** sqlite3_stmt *pStmt;
+** while( (pStmt = sqlite3_next_stmt(db, 0))!=0 ){
+**     sqlite3_finalize(pStmt);
+** }
+**
** -** What happens to pending transactions? Are they -** rolled back, or abandoned? +** If [sqlite3_close()] is invoked while a transaction is open, +** the transaction is automatically rolled back. ** ** INVARIANTS: ** -** {F12011} The [sqlite3_close()] interface destroys an [sqlite3] object -** allocated by a prior call to [sqlite3_open()], -** [sqlite3_open16()], or [sqlite3_open_v2()]. +** {H12011} A successful call to [sqlite3_close(C)] shall destroy the +** [database connection] object C. ** -** {F12012} The [sqlite3_close()] function releases all memory used by the -** connection and closes all open files. +** {H12012} A successful call to [sqlite3_close(C)] shall return SQLITE_OK. +** +** {H12013} A successful call to [sqlite3_close(C)] shall release all +** memory and system resources associated with [database connection] +** C. ** -** {F12013} If the database connection contains -** [prepared statements] that have not been -** finalized by [sqlite3_finalize()], then [sqlite3_close()] -** returns [SQLITE_BUSY] and leaves the connection open. +** {H12014} A call to [sqlite3_close(C)] on a [database connection] C that +** has one or more open [prepared statements] shall fail with +** an [SQLITE_BUSY] error code. ** -** {F12014} Giving sqlite3_close() a NULL pointer is a harmless no-op. +** {H12015} A call to [sqlite3_close(C)] where C is a NULL pointer shall +** be a harmless no-op returning SQLITE_OK. ** -** LIMITATIONS: +** {H12019} When [sqlite3_close(C)] is invoked on a [database connection] C +** that has a pending transaction, the transaction shall be +** rolled back. ** -** {U12015} The parameter to [sqlite3_close()] must be an [sqlite3] object -** pointer previously obtained from [sqlite3_open()] or the -** equivalent, or NULL. +** ASSUMPTIONS: ** -** {U12016} The parameter to [sqlite3_close()] must not have been previously -** closed. +** {A12016} The C parameter to [sqlite3_close(C)] must be either a NULL +** pointer or an [sqlite3] object pointer obtained +** from [sqlite3_open()], [sqlite3_open16()], or +** [sqlite3_open_v2()], and not previously closed. */ SQLITE_API int sqlite3_close(sqlite3 *); @@ -715,115 +754,129 @@ SQLITE_API int sqlite3_close(sqlite3 *); typedef int (*sqlite3_callback)(void*,int,char**, char**); /* -** CAPI3REF: One-Step Query Execution Interface {F12100} +** CAPI3REF: One-Step Query Execution Interface {H12100} ** -** The sqlite3_exec() interface is a convenient way of running -** one or more SQL statements without a lot of C code. The -** SQL statements are passed in as the second parameter to -** sqlite3_exec(). The statements are evaluated one by one -** until either an error or an interrupt is encountered or -** until they are all done. The 3rd parameter is an optional -** callback that is invoked once for each row of any query results -** produced by the SQL statements. The 5th parameter tells where +** The sqlite3_exec() interface is a convenient way of running one or more +** SQL statements without having to write a lot of C code. The UTF-8 encoded +** SQL statements are passed in as the second parameter to sqlite3_exec(). +** The statements are evaluated one by one until either an error or +** an interrupt is encountered, or until they are all done. The 3rd parameter +** is an optional callback that is invoked once for each row of any query +** results produced by the SQL statements. The 5th parameter tells where ** to write any error messages. ** +** The error message passed back through the 5th parameter is held +** in memory obtained from [sqlite3_malloc()]. To avoid a memory leak, +** the calling application should call [sqlite3_free()] on any error +** message returned through the 5th parameter when it has finished using +** the error message. +** +** If the SQL statement in the 2nd parameter is NULL or an empty string +** or a string containing only whitespace and comments, then no SQL +** statements are evaluated and the database is not changed. +** ** The sqlite3_exec() interface is implemented in terms of ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()]. -** The sqlite3_exec() routine does nothing that cannot be done +** The sqlite3_exec() routine does nothing to the database that cannot be done ** by [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()]. -** The sqlite3_exec() is just a convenient wrapper. ** ** INVARIANTS: -** -** {F12101} The [sqlite3_exec()] interface evaluates zero or more UTF-8 -** encoded, semicolon-separated, SQL statements in the -** zero-terminated string of its 2nd parameter within the -** context of the [sqlite3] object given in the 1st parameter. ** -** {F12104} The return value of [sqlite3_exec()] is SQLITE_OK if all -** SQL statements run successfully. +** {H12101} A successful invocation of [sqlite3_exec(D,S,C,A,E)] +** shall sequentially evaluate all of the UTF-8 encoded, +** semicolon-separated SQL statements in the zero-terminated +** string S within the context of the [database connection] D. +** +** {H12102} If the S parameter to [sqlite3_exec(D,S,C,A,E)] is NULL then +** the actions of the interface shall be the same as if the +** S parameter were an empty string. ** -** {F12105} The return value of [sqlite3_exec()] is an appropriate -** non-zero error code if any SQL statement fails. +** {H12104} The return value of [sqlite3_exec()] shall be [SQLITE_OK] if all +** SQL statements run successfully and to completion. ** -** {F12107} If one or more of the SQL statements handed to [sqlite3_exec()] +** {H12105} The return value of [sqlite3_exec()] shall be an appropriate +** non-zero [error code] if any SQL statement fails. +** +** {H12107} If one or more of the SQL statements handed to [sqlite3_exec()] ** return results and the 3rd parameter is not NULL, then -** the callback function specified by the 3rd parameter is +** the callback function specified by the 3rd parameter shall be ** invoked once for each row of result. ** -** {F12110} If the callback returns a non-zero value then [sqlite3_exec()] -** will aborted the SQL statement it is currently evaluating, +** {H12110} If the callback returns a non-zero value then [sqlite3_exec()] +** shall abort the SQL statement it is currently evaluating, ** skip all subsequent SQL statements, and return [SQLITE_ABORT]. -** What happens to *errmsg here? Does the result code for -** sqlite3_errcode() get set? ** -** {F12113} The [sqlite3_exec()] routine will pass its 4th parameter through +** {H12113} The [sqlite3_exec()] routine shall pass its 4th parameter through ** as the 1st parameter of the callback. ** -** {F12116} The [sqlite3_exec()] routine sets the 2nd parameter of its +** {H12116} The [sqlite3_exec()] routine shall set the 2nd parameter of its ** callback to be the number of columns in the current row of ** result. ** -** {F12119} The [sqlite3_exec()] routine sets the 3rd parameter of its +** {H12119} The [sqlite3_exec()] routine shall set the 3rd parameter of its ** callback to be an array of pointers to strings holding the ** values for each column in the current result set row as ** obtained from [sqlite3_column_text()]. ** -** {F12122} The [sqlite3_exec()] routine sets the 4th parameter of its +** {H12122} The [sqlite3_exec()] routine shall set the 4th parameter of its ** callback to be an array of pointers to strings holding the ** names of result columns as obtained from [sqlite3_column_name()]. ** -** {F12125} If the 3rd parameter to [sqlite3_exec()] is NULL then -** [sqlite3_exec()] never invokes a callback. All query -** results are silently discarded. +** {H12125} If the 3rd parameter to [sqlite3_exec()] is NULL then +** [sqlite3_exec()] shall silently discard query results. ** -** {F12128} If an error occurs while parsing or evaluating any of the SQL -** statements handed to [sqlite3_exec()] then [sqlite3_exec()] will -** return an [error code] other than [SQLITE_OK]. +** {H12131} If an error occurs while parsing or evaluating any of the SQL +** statements in the S parameter of [sqlite3_exec(D,S,C,A,E)] and if +** the E parameter is not NULL, then [sqlite3_exec()] shall store +** in *E an appropriate error message written into memory obtained +** from [sqlite3_malloc()]. ** -** {F12131} If an error occurs while parsing or evaluating any of the SQL -** handed to [sqlite3_exec()] and if the 5th parameter (errmsg) -** to [sqlite3_exec()] is not NULL, then an error message is -** allocated using the equivalent of [sqlite3_mprintf()] and -** *errmsg is made to point to that message. +** {H12134} The [sqlite3_exec(D,S,C,A,E)] routine shall set the value of +** *E to NULL if E is not NULL and there are no errors. ** -** {F12134} The [sqlite3_exec()] routine does not change the value of -** *errmsg if errmsg is NULL or if there are no errors. +** {H12137} The [sqlite3_exec(D,S,C,A,E)] function shall set the [error code] +** and message accessible via [sqlite3_errcode()], +** [sqlite3_errmsg()], and [sqlite3_errmsg16()]. ** -** {F12137} The [sqlite3_exec()] function sets the error code and message -** accessible via [sqlite3_errcode()], [sqlite3_errmsg()], and -** [sqlite3_errmsg16()]. +** {H12138} If the S parameter to [sqlite3_exec(D,S,C,A,E)] is NULL or an +** empty string or contains nothing other than whitespace, comments, +** and/or semicolons, then results of [sqlite3_errcode()], +** [sqlite3_errmsg()], and [sqlite3_errmsg16()] +** shall reset to indicate no errors. ** -** LIMITATIONS: +** ASSUMPTIONS: ** -** {U12141} The first parameter to [sqlite3_exec()] must be an valid and open +** {A12141} The first parameter to [sqlite3_exec()] must be an valid and open ** [database connection]. ** -** {U12142} The database connection must not be closed while +** {A12142} The database connection must not be closed while ** [sqlite3_exec()] is running. -** -** {U12143} The calling function is should use [sqlite3_free()] to free +** +** {A12143} The calling function should use [sqlite3_free()] to free ** the memory that *errmsg is left pointing at once the error ** message is no longer needed. ** -** {U12145} The SQL statement text in the 2nd parameter to [sqlite3_exec()] +** {A12145} The SQL statement text in the 2nd parameter to [sqlite3_exec()] ** must remain unchanged while [sqlite3_exec()] is running. */ SQLITE_API int sqlite3_exec( sqlite3*, /* An open database */ - const char *sql, /* SQL to be evaluted */ + const char *sql, /* SQL to be evaluated */ int (*callback)(void*,int,char**,char**), /* Callback function */ void *, /* 1st argument to callback */ char **errmsg /* Error msg written here */ ); /* -** CAPI3REF: Result Codes {F10210} +** CAPI3REF: Result Codes {H10210} ** KEYWORDS: SQLITE_OK {error code} {error codes} +** KEYWORDS: {result code} {result codes} ** ** Many SQLite functions return an integer result code from the set shown ** here in order to indicates success or failure. ** +** New error codes may be added in future versions of SQLite. +** ** See also: [SQLITE_IOERR_READ | extended result codes] */ #define SQLITE_OK 0 /* Successful result */ @@ -859,20 +912,20 @@ SQLITE_API int sqlite3_exec( /* end-of-error-codes */ /* -** CAPI3REF: Extended Result Codes {F10220} +** CAPI3REF: Extended Result Codes {H10220} ** KEYWORDS: {extended error code} {extended error codes} -** KEYWORDS: {extended result codes} +** KEYWORDS: {extended result code} {extended result codes} ** ** In its default configuration, SQLite API routines return one of 26 integer -** [SQLITE_OK | result codes]. However, experience has shown that -** many of these result codes are too course-grained. They do not provide as +** [SQLITE_OK | result codes]. However, experience has shown that many of +** these result codes are too coarse-grained. They do not provide as ** much information about problems as programmers might like. In an effort to ** address this, newer versions of SQLite (version 3.3.8 and later) include ** support for additional result codes that provide more detailed information ** about errors. The extended result codes are enabled or disabled -** for each database connection using the [sqlite3_extended_result_codes()] -** API. -** +** on a per database connection basis using the +** [sqlite3_extended_result_codes()] API. +** ** Some of the available extended result codes are listed here. ** One may expect the number of extended result codes will be expand ** over time. Software that uses extended result codes should expect @@ -880,35 +933,38 @@ SQLITE_API int sqlite3_exec( ** ** The SQLITE_OK result code will never be extended. It will always ** be exactly zero. -** +** ** INVARIANTS: ** -** {F10223} The symbolic name for an extended result code always contains +** {H10223} The symbolic name for an extended result code shall contains ** a related primary result code as a prefix. ** -** {F10224} Primary result code names contain a single "_" character. +** {H10224} Primary result code names shall contain a single "_" character. ** -** {F10225} Extended result code names contain two or more "_" characters. +** {H10225} Extended result code names shall contain two or more "_" characters. ** -** {F10226} The numeric value of an extended result code contains the +** {H10226} The numeric value of an extended result code shall contain the ** numeric value of its corresponding primary result code in ** its least significant 8 bits. */ -#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) -#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) -#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) -#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) -#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) -#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) -#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) -#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) -#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) -#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) -#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) -#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) - -/* -** CAPI3REF: Flags For File Open Operations {F10230} +#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) +#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) +#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) +#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) +#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) +#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) +#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) +#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) +#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) +#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) +#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) +#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) +#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) +#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) +#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) + +/* +** CAPI3REF: Flags For File Open Operations {H10230} ** ** These bit values are intended for use in the ** 3rd parameter to the [sqlite3_open_v2()] interface and @@ -927,9 +983,11 @@ SQLITE_API int sqlite3_exec( #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 #define SQLITE_OPEN_SUBJOURNAL 0x00002000 #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 +#define SQLITE_OPEN_NOMUTEX 0x00008000 +#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* -** CAPI3REF: Device Characteristics {F10240} +** CAPI3REF: Device Characteristics {H10240} ** ** The xDeviceCapabilities method of the [sqlite3_io_methods] ** object returns an integer which is a vector of the these @@ -961,7 +1019,7 @@ SQLITE_API int sqlite3_exec( #define SQLITE_IOCAP_SEQUENTIAL 0x00000400 /* -** CAPI3REF: File Locking Levels {F10250} +** CAPI3REF: File Locking Levels {H10250} ** ** SQLite uses one of these integer values as the second ** argument to calls it makes to the xLock() and xUnlock() methods @@ -974,7 +1032,7 @@ SQLITE_API int sqlite3_exec( #define SQLITE_LOCK_EXCLUSIVE 4 /* -** CAPI3REF: Synchronization Type Flags {F10260} +** CAPI3REF: Synchronization Type Flags {H10260} ** ** When SQLite invokes the xSync() method of an ** [sqlite3_io_methods] object it uses a combination of @@ -982,17 +1040,16 @@ SQLITE_API int sqlite3_exec( ** ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the ** sync operation only needs to flush data to mass storage. Inode -** information need not be flushed. The SQLITE_SYNC_NORMAL flag means -** to use normal fsync() semantics. The SQLITE_SYNC_FULL flag means +** information need not be flushed. The SQLITE_SYNC_NORMAL flag means +** to use normal fsync() semantics. The SQLITE_SYNC_FULL flag means ** to use Mac OS-X style fullsync instead of fsync(). */ #define SQLITE_SYNC_NORMAL 0x00002 #define SQLITE_SYNC_FULL 0x00003 #define SQLITE_SYNC_DATAONLY 0x00010 - /* -** CAPI3REF: OS Interface Open File Handle {F11110} +** CAPI3REF: OS Interface Open File Handle {H11110} ** ** An [sqlite3_file] object represents an open file in the OS ** interface layer. Individual OS interface implementations will @@ -1007,19 +1064,20 @@ struct sqlite3_file { }; /* -** CAPI3REF: OS Interface File Virtual Methods Object {F11120} +** CAPI3REF: OS Interface File Virtual Methods Object {H11120} ** -** Every file opened by the [sqlite3_vfs] xOpen method contains a pointer to -** an instance of this object. This object defines the -** methods used to perform various operations against the open file. +** Every file opened by the [sqlite3_vfs] xOpen method populates an +** [sqlite3_file] object (or, more commonly, a subclass of the +** [sqlite3_file] object) with a pointer to an instance of this object. +** This object defines the methods used to perform various operations +** against the open file represented by the [sqlite3_file] object. ** ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). -* The second choice is an -** OS-X style fullsync. The SQLITE_SYNC_DATA flag may be ORed in to -** indicate that only the data of the file and not its inode needs to be -** synced. -** +** The second choice is a Mac OS-X style fullsync. The [SQLITE_SYNC_DATAONLY] +** flag may be ORed in to indicate that only the data of the file +** and not its inode needs to be synced. +** ** The integer values to xLock() and xUnlock() are one of **
    **
  • [SQLITE_LOCK_NONE], @@ -1028,26 +1086,24 @@ struct sqlite3_file { **
  • [SQLITE_LOCK_PENDING], or **
  • [SQLITE_LOCK_EXCLUSIVE]. **
-** xLock() increases the lock. xUnlock() decreases the lock. -** The xCheckReservedLock() method looks -** to see if any database connection, either in this -** process or in some other process, is holding an RESERVED, +** xLock() increases the lock. xUnlock() decreases the lock. +** The xCheckReservedLock() method checks whether any database connection, +** either in this process or in some other process, is holding a RESERVED, ** PENDING, or EXCLUSIVE lock on the file. It returns true -** if such a lock exists and false if not. -** +** if such a lock exists and false otherwise. +** ** The xFileControl() method is a generic interface that allows custom ** VFS implementations to directly control an open file using the -** [sqlite3_file_control()] interface. The second "op" argument -** is an integer opcode. The third -** argument is a generic pointer which is intended to be a pointer -** to a structure that may contain arguments or space in which to +** [sqlite3_file_control()] interface. The second "op" argument is an +** integer opcode. The third argument is a generic pointer intended to +** point to a structure that may contain arguments or space in which to ** write return values. Potential uses for xFileControl() might be ** functions to enable blocking locks with timeouts, to change the ** locking strategy (for example to use dot-file locks), to inquire ** about the status of a lock, or to break stale locks. The SQLite -** core reserves opcodes less than 100 for its own use. +** core reserves all opcodes less than 100 for its own use. ** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available. -** Applications that define a custom xFileControl method should use opcodes +** Applications that define a custom xFileControl method should use opcodes ** greater than 100 to avoid conflicts. ** ** The xSectorSize() method returns the sector size of the @@ -1093,7 +1149,7 @@ struct sqlite3_io_methods { int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); int (*xLock)(sqlite3_file*, int); int (*xUnlock)(sqlite3_file*, int); - int (*xCheckReservedLock)(sqlite3_file*); + int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); int (*xFileControl)(sqlite3_file*, int op, void *pArg); int (*xSectorSize)(sqlite3_file*); int (*xDeviceCharacteristics)(sqlite3_file*); @@ -1101,10 +1157,10 @@ struct sqlite3_io_methods { }; /* -** CAPI3REF: Standard File Control Opcodes {F11310} +** CAPI3REF: Standard File Control Opcodes {H11310} ** ** These integer constants are opcodes for the xFileControl method -** of the [sqlite3_io_methods] object and to the [sqlite3_file_control()] +** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] ** interface. ** ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This @@ -1118,7 +1174,7 @@ struct sqlite3_io_methods { #define SQLITE_FCNTL_LOCKSTATE 1 /* -** CAPI3REF: Mutex Handle {F17110} +** CAPI3REF: Mutex Handle {H17110} ** ** The mutex module within SQLite defines [sqlite3_mutex] to be an ** abstract type for a mutex object. The SQLite core never looks @@ -1130,15 +1186,18 @@ struct sqlite3_io_methods { typedef struct sqlite3_mutex sqlite3_mutex; /* -** CAPI3REF: OS Interface Object {F11140} +** CAPI3REF: OS Interface Object {H11140} ** -** An instance of this object defines the interface between the -** SQLite core and the underlying operating system. The "vfs" +** An instance of the sqlite3_vfs object defines the interface between +** the SQLite core and the underlying operating system. The "vfs" ** in the name of the object stands for "virtual file system". ** -** The iVersion field is initially 1 but may be larger for future -** versions of SQLite. Additional fields may be appended to this -** object when the iVersion value is increased. +** The value of the iVersion field is initially 1 but may be larger in +** future versions of SQLite. Additional fields may be appended to this +** object when the iVersion value is increased. Note that the structure +** of the sqlite3_vfs object changes in the transaction between +** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not +** modified. ** ** The szOsFile field is the size of the subclassed [sqlite3_file] ** structure used by this VFS. mxPathname is the maximum length of @@ -1148,9 +1207,10 @@ typedef struct sqlite3_mutex sqlite3_mutex; ** the pNext pointer. The [sqlite3_vfs_register()] ** and [sqlite3_vfs_unregister()] interfaces manage this list ** in a thread-safe way. The [sqlite3_vfs_find()] interface -** searches the list. +** searches the list. Neither the application code nor the VFS +** implementation should use the pNext pointer. ** -** The pNext field is the only field in the sqlite3_vfs +** The pNext field is the only field in the sqlite3_vfs ** structure that SQLite will ever modify. SQLite will only access ** or modify this field while holding a particular static mutex. ** The application should never modify anything within the sqlite3_vfs @@ -1159,23 +1219,28 @@ typedef struct sqlite3_mutex sqlite3_mutex; ** The zName field holds the name of the VFS module. The name must ** be unique across all VFS modules. ** -** {F11141} SQLite will guarantee that the zFilename string passed to -** xOpen() is a full pathname as generated by xFullPathname() and -** that the string will be valid and unchanged until xClose() is -** called. {END} So the [sqlite3_file] can store a pointer to the +** {H11141} SQLite will guarantee that the zFilename parameter to xOpen +** is either a NULL pointer or string obtained +** from xFullPathname(). SQLite further guarantees that +** the string will be valid and unchanged until xClose() is +** called. {END} Because of the previous sentense, +** the [sqlite3_file] can safely store a pointer to the ** filename if it needs to remember the filename for some reason. +** If the zFilename parameter is xOpen is a NULL pointer then xOpen +** must invite its own temporary name for the file. Whenever the +** xFilename parameter is NULL it will also be the case that the +** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. ** -** {F11142} The flags argument to xOpen() includes all bits set in +** {H11142} The flags argument to xOpen() includes all bits set in ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] ** or [sqlite3_open16()] is used, then flags includes at least ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. {END} ** If xOpen() opens a file read-only then it sets *pOutFlags to -** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be -** set. -** -** {F11143} SQLite will also add one of the following flags to the xOpen() +** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. +** +** {H11143} SQLite will also add one of the following flags to the xOpen() ** call, depending on the object being opened: -** +** **
    **
  • [SQLITE_OPEN_MAIN_DB] **
  • [SQLITE_OPEN_MAIN_JOURNAL] @@ -1187,59 +1252,56 @@ typedef struct sqlite3_mutex sqlite3_mutex; **
{END} ** ** The file I/O implementation can use the object type flags to -** changes the way it deals with files. For example, an application +** change the way it deals with files. For example, an application ** that does not care about crash recovery or rollback might make ** the open of a journal file a no-op. Writes to this journal would -** also be no-ops, and any attempt to read the journal would return -** SQLITE_IOERR. Or the implementation might recognize that a database -** file will be doing page-aligned sector reads and writes in a random +** also be no-ops, and any attempt to read the journal would return +** SQLITE_IOERR. Or the implementation might recognize that a database +** file will be doing page-aligned sector reads and writes in a random ** order and set up its I/O subsystem accordingly. -** -** SQLite might also add one of the following flags to the xOpen -** method: -** +** +** SQLite might also add one of the following flags to the xOpen method: +** **
    **
  • [SQLITE_OPEN_DELETEONCLOSE] **
  • [SQLITE_OPEN_EXCLUSIVE] **
-** -** {F11145} The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be -** deleted when it is closed. {F11146} The [SQLITE_OPEN_DELETEONCLOSE] -** will be set for TEMP databases, journals and for subjournals. -** {F11147} The [SQLITE_OPEN_EXCLUSIVE] flag means the file should be opened +** +** {H11145} The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be +** deleted when it is closed. {H11146} The [SQLITE_OPEN_DELETEONCLOSE] +** will be set for TEMP databases, journals and for subjournals. +** +** {H11147} The [SQLITE_OPEN_EXCLUSIVE] flag means the file should be opened ** for exclusive access. This flag is set for all files except -** for the main database file. {END} -** -** {F11148} At least szOsFile bytes of memory are allocated by SQLite -** to hold the [sqlite3_file] structure passed as the third -** argument to xOpen. {END} The xOpen method does not have to +** for the main database file. +** +** {H11148} At least szOsFile bytes of memory are allocated by SQLite +** to hold the [sqlite3_file] structure passed as the third +** argument to xOpen. {END} The xOpen method does not have to ** allocate the structure; it should just fill it in. -** -** {F11149} The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] -** to test for the existance of a file, -** or [SQLITE_ACCESS_READWRITE] to test to see -** if a file is readable and writable, or [SQLITE_ACCESS_READ] -** to test to see if a file is at least readable. {END} The file can be a +** +** {H11149} The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] +** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to +** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] +** to test whether a file is at least readable. {END} The file can be a ** directory. -** -** {F11150} SQLite will always allocate at least mxPathname+1 bytes for -** the output buffers for xGetTempname and xFullPathname. {F11151} The exact -** size of the output buffer is also passed as a parameter to both -** methods. {END} If the output buffer is not large enough, SQLITE_CANTOPEN -** should be returned. As this is handled as a fatal error by SQLite, -** vfs implementations should endeavor to prevent this by setting -** mxPathname to a sufficiently large value. -** +** +** {H11150} SQLite will always allocate at least mxPathname+1 bytes for the +** output buffer xFullPathname. {H11151} The exact size of the output buffer +** is also passed as a parameter to both methods. {END} If the output buffer +** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is +** handled as a fatal error by SQLite, vfs implementations should endeavor +** to prevent this by setting mxPathname to a sufficiently large value. +** ** The xRandomness(), xSleep(), and xCurrentTime() interfaces ** are not strictly a part of the filesystem, but they are ** included in the VFS structure for completeness. ** The xRandomness() function attempts to return nBytes bytes ** of good-quality randomness into zOut. The return value is -** the actual number of bytes of randomness obtained. The -** xSleep() method causes the calling thread to sleep for at +** the actual number of bytes of randomness obtained. +** The xSleep() method causes the calling thread to sleep for at ** least the number of microseconds given. The xCurrentTime() -** method returns a Julian Day Number for the current date and -** time. +** method returns a Julian Day Number for the current date and time. */ typedef struct sqlite3_vfs sqlite3_vfs; struct sqlite3_vfs { @@ -1252,8 +1314,7 @@ struct sqlite3_vfs { int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*, int flags, int *pOutFlags); int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); - int (*xAccess)(sqlite3_vfs*, const char *zName, int flags); - int (*xGetTempname)(sqlite3_vfs*, int nOut, char *zOut); + int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); @@ -1262,50 +1323,518 @@ struct sqlite3_vfs { int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); int (*xSleep)(sqlite3_vfs*, int microseconds); int (*xCurrentTime)(sqlite3_vfs*, double*); + int (*xGetLastError)(sqlite3_vfs*, int, char *); /* New fields may be appended in figure versions. The iVersion ** value will increment whenever this happens. */ }; /* -** CAPI3REF: Flags for the xAccess VFS method {F11190} +** CAPI3REF: Flags for the xAccess VFS method {H11190} ** -** {F11191} These integer constants can be used as the third parameter to +** {H11191} These integer constants can be used as the third parameter to ** the xAccess method of an [sqlite3_vfs] object. {END} They determine -** what kind of permissions the xAccess method is -** looking for. {F11192} With SQLITE_ACCESS_EXISTS, the xAccess method -** simply checks to see if the file exists. {F11193} With -** SQLITE_ACCESS_READWRITE, the xAccess method checks to see -** if the file is both readable and writable. {F11194} With -** SQLITE_ACCESS_READ the xAccess method -** checks to see if the file is readable. +** what kind of permissions the xAccess method is looking for. +** {H11192} With SQLITE_ACCESS_EXISTS, the xAccess method +** simply checks whether the file exists. +** {H11193} With SQLITE_ACCESS_READWRITE, the xAccess method +** checks whether the file is both readable and writable. +** {H11194} With SQLITE_ACCESS_READ, the xAccess method +** checks whether the file is readable. */ #define SQLITE_ACCESS_EXISTS 0 #define SQLITE_ACCESS_READWRITE 1 #define SQLITE_ACCESS_READ 2 /* -** CAPI3REF: Enable Or Disable Extended Result Codes {F12200} +** CAPI3REF: Initialize The SQLite Library {H10130} +** +** The sqlite3_initialize() routine initializes the +** SQLite library. The sqlite3_shutdown() routine +** deallocates any resources that were allocated by sqlite3_initialize(). +** +** A call to sqlite3_initialize() is an "effective" call if it is +** the first time sqlite3_initialize() is invoked during the lifetime of +** the process, or if it is the first time sqlite3_initialize() is invoked +** following a call to sqlite3_shutdown(). Only an effective call +** of sqlite3_initialize() does any initialization. All other calls +** are harmless no-ops. +** +** Among other things, sqlite3_initialize() shall invoke +** sqlite3_os_init(). Similarly, sqlite3_shutdown() +** shall invoke sqlite3_os_end(). +** +** The sqlite3_initialize() routine returns [SQLITE_OK] on success. +** If for some reason, sqlite3_initialize() is unable to initialize +** the library (perhaps it is unable to allocate a needed resource such +** as a mutex) it returns an [error code] other than [SQLITE_OK]. +** +** The sqlite3_initialize() routine is called internally by many other +** SQLite interfaces so that an application usually does not need to +** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] +** calls sqlite3_initialize() so the SQLite library will be automatically +** initialized when [sqlite3_open()] is called if it has not be initialized +** already. However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] +** compile-time option, then the automatic calls to sqlite3_initialize() +** are omitted and the application must call sqlite3_initialize() directly +** prior to using any other SQLite interface. For maximum portability, +** it is recommended that applications always invoke sqlite3_initialize() +** directly prior to using any other SQLite interface. Future releases +** of SQLite may require this. In other words, the behavior exhibited +** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the +** default behavior in some future release of SQLite. +** +** The sqlite3_os_init() routine does operating-system specific +** initialization of the SQLite library. The sqlite3_os_end() +** routine undoes the effect of sqlite3_os_init(). Typical tasks +** performed by these routines include allocation or deallocation +** of static resources, initialization of global variables, +** setting up a default [sqlite3_vfs] module, or setting up +** a default configuration using [sqlite3_config()]. +** +** The application should never invoke either sqlite3_os_init() +** or sqlite3_os_end() directly. The application should only invoke +** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() +** interface is called automatically by sqlite3_initialize() and +** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate +** implementations for sqlite3_os_init() and sqlite3_os_end() +** are built into SQLite when it is compiled for unix, windows, or os/2. +** When built for other platforms (using the [SQLITE_OS_OTHER=1] compile-time +** option) the application must supply a suitable implementation for +** sqlite3_os_init() and sqlite3_os_end(). An application-supplied +** implementation of sqlite3_os_init() or sqlite3_os_end() +** must return [SQLITE_OK] on success and some other [error code] upon +** failure. +*/ +SQLITE_API int sqlite3_initialize(void); +SQLITE_API int sqlite3_shutdown(void); +SQLITE_API int sqlite3_os_init(void); +SQLITE_API int sqlite3_os_end(void); + +/* +** CAPI3REF: Configuring The SQLite Library {H14100} +** EXPERIMENTAL +** +** The sqlite3_config() interface is used to make global configuration +** changes to SQLite in order to tune SQLite to the specific needs of +** the application. The default configuration is recommended for most +** applications and so this routine is usually not necessary. It is +** provided to support rare applications with unusual needs. +** +** The sqlite3_config() interface is not threadsafe. The application +** must insure that no other SQLite interfaces are invoked by other +** threads while sqlite3_config() is running. Furthermore, sqlite3_config() +** may only be invoked prior to library initialization using +** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. +** Note, however, that sqlite3_config() can be called as part of the +** implementation of an application-defined [sqlite3_os_init()]. +** +** The first argument to sqlite3_config() is an integer +** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines +** what property of SQLite is to be configured. Subsequent arguments +** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | configuration option] +** in the first argument. +** +** When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. +** If the option is unknown or SQLite is unable to set the option +** then this routine returns a non-zero [error code]. +** +** INVARIANTS: +** +** {H14103} A successful invocation of [sqlite3_config()] shall return +** [SQLITE_OK]. +** +** {H14106} The [sqlite3_config()] interface shall return [SQLITE_MISUSE] +** if it is invoked in between calls to [sqlite3_initialize()] and +** [sqlite3_shutdown()]. +** +** {H14120} A successful call to [sqlite3_config]([SQLITE_CONFIG_SINGLETHREAD]) +** shall set the default [threading mode] to Single-thread. +** +** {H14123} A successful call to [sqlite3_config]([SQLITE_CONFIG_MULTITHREAD]) +** shall set the default [threading mode] to Multi-thread. +** +** {H14126} A successful call to [sqlite3_config]([SQLITE_CONFIG_SERIALIZED]) +** shall set the default [threading mode] to Serialized. +** +** {H14129} A successful call to [sqlite3_config]([SQLITE_CONFIG_MUTEX],X) +** where X is a pointer to an initialized [sqlite3_mutex_methods] +** object shall cause all subsequent mutex operations performed +** by SQLite to use the mutex methods that were present in X +** during the call to [sqlite3_config()]. +** +** {H14132} A successful call to [sqlite3_config]([SQLITE_CONFIG_GETMUTEX],X) +** where X is a pointer to an [sqlite3_mutex_methods] object +** shall overwrite the content of [sqlite3_mutex_methods] object +** with the mutex methods currently in use by SQLite. +** +** {H14135} A successful call to [sqlite3_config]([SQLITE_CONFIG_MALLOC],M) +** where M is a pointer to an initialized [sqlite3_mem_methods] +** object shall cause all subsequent memory allocation operations +** performed by SQLite to use the methods that were present in +** M during the call to [sqlite3_config()]. +** +** {H14138} A successful call to [sqlite3_config]([SQLITE_CONFIG_GETMALLOC],M) +** where M is a pointer to an [sqlite3_mem_methods] object shall +** overwrite the content of [sqlite3_mem_methods] object with +** the memory allocation methods currently in use by +** SQLite. +** +** {H14141} A successful call to [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],1) +** shall enable the memory allocation status collection logic. +** +** {H14144} A successful call to [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],0) +** shall disable the memory allocation status collection logic. +** +** {H14147} The memory allocation status collection logic shall be +** enabled by default. +** +** {H14150} A successful call to [sqlite3_config]([SQLITE_CONFIG_SCRATCH],S,Z,N) +** where Z and N are non-negative integers and +** S is a pointer to an aligned memory buffer not less than +** Z*N bytes in size shall cause S to be used by the +** [scratch memory allocator] for as many as N simulataneous +** allocations each of size Z. +** +** {H14153} A successful call to [sqlite3_config]([SQLITE_CONFIG_SCRATCH],S,Z,N) +** where S is a NULL pointer shall disable the +** [scratch memory allocator]. +** +** {H14156} A successful call to +** [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],S,Z,N) +** where Z and N are non-negative integers and +** S is a pointer to an aligned memory buffer not less than +** Z*N bytes in size shall cause S to be used by the +** [pagecache memory allocator] for as many as N simulataneous +** allocations each of size Z. +** +** {H14159} A successful call to +** [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],S,Z,N) +** where S is a NULL pointer shall disable the +** [pagecache memory allocator]. +** +** {H14162} A successful call to [sqlite3_config]([SQLITE_CONFIG_HEAP],H,Z,N) +** where Z and N are non-negative integers and +** H is a pointer to an aligned memory buffer not less than +** Z bytes in size shall enable the [memsys5] memory allocator +** and cause it to use buffer S as its memory source and to use +** a minimum allocation size of N. +** +** {H14165} A successful call to [sqlite3_config]([SQLITE_CONFIG_HEAP],H,Z,N) +** where H is a NULL pointer shall disable the +** [memsys5] memory allocator. +** +** {H14168} A successful call to [sqlite3_config]([SQLITE_CONFIG_LOOKASIDE],Z,N) +** shall cause the default [lookaside memory allocator] configuration +** for new [database connections] to be N slots of Z bytes each. +*/ +SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_config(int, ...); + +/* +** CAPI3REF: Configure database connections {H14200} +** EXPERIMENTAL +** +** The sqlite3_db_config() interface is used to make configuration +** changes to a [database connection]. The interface is similar to +** [sqlite3_config()] except that the changes apply to a single +** [database connection] (specified in the first argument). The +** sqlite3_db_config() interface can only be used immediately after +** the database connection is created using [sqlite3_open()], +** [sqlite3_open16()], or [sqlite3_open_v2()]. +** +** The second argument to sqlite3_db_config(D,V,...) is the +** configuration verb - an integer code that indicates what +** aspect of the [database connection] is being configured. +** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE]. +** New verbs are likely to be added in future releases of SQLite. +** Additional arguments depend on the verb. +** +** INVARIANTS: +** +** {H14203} A call to [sqlite3_db_config(D,V,...)] shall return [SQLITE_OK] +** if and only if the call is successful. +** +** {H14206} If one or more slots of the [lookaside memory allocator] for +** [database connection] D are in use, then a call to +** [sqlite3_db_config](D,[SQLITE_DBCONFIG_LOOKASIDE],...) shall +** fail with an [SQLITE_BUSY] return code. +** +** {H14209} A successful call to +** [sqlite3_db_config](D,[SQLITE_DBCONFIG_LOOKASIDE],B,Z,N) where +** D is an open [database connection] and Z and N are positive +** integers and B is an aligned buffer at least Z*N bytes in size +** shall cause the [lookaside memory allocator] for D to use buffer B +** with N slots of Z bytes each. +** +** {H14212} A successful call to +** [sqlite3_db_config](D,[SQLITE_DBCONFIG_LOOKASIDE],B,Z,N) where +** D is an open [database connection] and Z and N are positive +** integers and B is NULL pointer shall cause the +** [lookaside memory allocator] for D to a obtain Z*N byte buffer +** from the primary memory allocator and use that buffer +** with N lookaside slots of Z bytes each. +** +** {H14215} A successful call to +** [sqlite3_db_config](D,[SQLITE_DBCONFIG_LOOKASIDE],B,Z,N) where +** D is an open [database connection] and Z and N are zero shall +** disable the [lookaside memory allocator] for D. +** +** +*/ +SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_db_config(sqlite3*, int op, ...); + +/* +** CAPI3REF: Memory Allocation Routines {H10155} +** EXPERIMENTAL +** +** An instance of this object defines the interface between SQLite +** and low-level memory allocation routines. +** +** This object is used in only one place in the SQLite interface. +** A pointer to an instance of this object is the argument to +** [sqlite3_config()] when the configuration option is +** [SQLITE_CONFIG_MALLOC]. By creating an instance of this object +** and passing it to [sqlite3_config()] during configuration, an +** application can specify an alternative memory allocation subsystem +** for SQLite to use for all of its dynamic memory needs. +** +** Note that SQLite comes with a built-in memory allocator that is +** perfectly adequate for the overwhelming majority of applications +** and that this object is only useful to a tiny minority of applications +** with specialized memory allocation requirements. This object is +** also used during testing of SQLite in order to specify an alternative +** memory allocator that simulates memory out-of-memory conditions in +** order to verify that SQLite recovers gracefully from such +** conditions. +** +** The xMalloc, xFree, and xRealloc methods must work like the +** malloc(), free(), and realloc() functions from the standard library. +** +** xSize should return the allocated size of a memory allocation +** previously obtained from xMalloc or xRealloc. The allocated size +** is always at least as big as the requested size but may be larger. +** +** The xRoundup method returns what would be the allocated size of +** a memory allocation given a particular requested size. Most memory +** allocators round up memory allocations at least to the next multiple +** of 8. Some allocators round up to a larger multiple or to a power of 2. +** +** The xInit method initializes the memory allocator. (For example, +** it might allocate any require mutexes or initialize internal data +** structures. The xShutdown method is invoked (indirectly) by +** [sqlite3_shutdown()] and should deallocate any resources acquired +** by xInit. The pAppData pointer is used as the only parameter to +** xInit and xShutdown. +*/ +typedef struct sqlite3_mem_methods sqlite3_mem_methods; +struct sqlite3_mem_methods { + void *(*xMalloc)(int); /* Memory allocation function */ + void (*xFree)(void*); /* Free a prior allocation */ + void *(*xRealloc)(void*,int); /* Resize an allocation */ + int (*xSize)(void*); /* Return the size of an allocation */ + int (*xRoundup)(int); /* Round up request size to allocation size */ + int (*xInit)(void*); /* Initialize the memory allocator */ + void (*xShutdown)(void*); /* Deinitialize the memory allocator */ + void *pAppData; /* Argument to xInit() and xShutdown() */ +}; + +/* +** CAPI3REF: Configuration Options {H10160} +** EXPERIMENTAL +** +** These constants are the available integer configuration options that +** can be passed as the first argument to the [sqlite3_config()] interface. +** +** New configuration options may be added in future releases of SQLite. +** Existing configuration options might be discontinued. Applications +** should check the return code from [sqlite3_config()] to make sure that +** the call worked. The [sqlite3_config()] interface will return a +** non-zero [error code] if a discontinued or unsupported configuration option +** is invoked. +** +**
+**
SQLITE_CONFIG_SINGLETHREAD
+**
There are no arguments to this option. This option disables +** all mutexing and puts SQLite into a mode where it can only be used +** by a single thread.
+** +**
SQLITE_CONFIG_MULTITHREAD
+**
There are no arguments to this option. This option disables +** mutexing on [database connection] and [prepared statement] objects. +** The application is responsible for serializing access to +** [database connections] and [prepared statements]. But other mutexes +** are enabled so that SQLite will be safe to use in a multi-threaded +** environment as long as no two threads attempt to use the same +** [database connection] at the same time. See the [threading mode] +** documentation for additional information.
+** +**
SQLITE_CONFIG_SERIALIZED
+**
There are no arguments to this option. This option enables +** all mutexes including the recursive +** mutexes on [database connection] and [prepared statement] objects. +** In this mode (which is the default when SQLite is compiled with +** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access +** to [database connections] and [prepared statements] so that the +** application is free to use the same [database connection] or the +** same [prepared statement] in different threads at the same time. +** See the [threading mode] documentation for additional information.
+** +**
SQLITE_CONFIG_MALLOC
+**
This option takes a single argument which is a pointer to an +** instance of the [sqlite3_mem_methods] structure. The argument specifies +** alternative low-level memory allocation routines to be used in place of +** the memory allocation routines built into SQLite.
+** +**
SQLITE_CONFIG_GETMALLOC
+**
This option takes a single argument which is a pointer to an +** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods] +** structure is filled with the currently defined memory allocation routines. +** This option can be used to overload the default memory allocation +** routines with a wrapper that simulations memory allocation failure or +** tracks memory usage, for example.
+** +**
SQLITE_CONFIG_MEMSTATUS
+**
This option takes single argument of type int, interpreted as a +** boolean, which enables or disables the collection of memory allocation +** statistics. When disabled, the following SQLite interfaces become +** non-operational: +**
    +**
  • [sqlite3_memory_used()] +**
  • [sqlite3_memory_highwater()] +**
  • [sqlite3_soft_heap_limit()] +**
  • [sqlite3_status()] +**
+**
+** +**
SQLITE_CONFIG_SCRATCH
+**
This option specifies a static memory buffer that SQLite can use for +** scratch memory. There are three arguments: A pointer to the memory, the +** size of each scratch buffer (sz), and the number of buffers (N). The sz +** argument must be a multiple of 16. The sz parameter should be a few bytes +** larger than the actual scratch space required due internal overhead. +** The first +** argument should point to an allocation of at least sz*N bytes of memory. +** SQLite will use no more than one scratch buffer at once per thread, so +** N should be set to the expected maximum number of threads. The sz +** parameter should be 6 times the size of the largest database page size. +** Scratch buffers are used as part of the btree balance operation. If +** The btree balancer needs additional memory beyond what is provided by +** scratch buffers or if no scratch buffer space is specified, then SQLite +** goes to [sqlite3_malloc()] to obtain the memory it needs.
+** +**
SQLITE_CONFIG_PAGECACHE
+**
This option specifies a static memory buffer that SQLite can use for +** the database page cache. There are three arguments: A pointer to the +** memory, the size of each page buffer (sz), and the number of pages (N). +** The sz argument must be a power of two between 512 and 32768. The first +** argument should point to an allocation of at least sz*N bytes of memory. +** SQLite will use the memory provided by the first argument to satisfy its +** memory needs for the first N pages that it adds to cache. If additional +** page cache memory is needed beyond what is provided by this option, then +** SQLite goes to [sqlite3_malloc()] for the additional storage space. +** The implementation might use one or more of the N buffers to hold +** memory accounting information.
+** +**
SQLITE_CONFIG_HEAP
+**
This option specifies a static memory buffer that SQLite will use +** for all of its dynamic memory allocation needs beyond those provided +** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE]. +** There are three arguments: A pointer to the memory, the number of +** bytes in the memory buffer, and the minimum allocation size. If +** the first pointer (the memory pointer) is NULL, then SQLite reverts +** to using its default memory allocator (the system malloc() implementation), +** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. If the +** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or +** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory +** allocator is engaged to handle all of SQLites memory allocation needs.
+** +**
SQLITE_CONFIG_MUTEX
+**
This option takes a single argument which is a pointer to an +** instance of the [sqlite3_mutex_methods] structure. The argument specifies +** alternative low-level mutex routines to be used in place +** the mutex routines built into SQLite.
+** +**
SQLITE_CONFIG_GETMUTEX
+**
This option takes a single argument which is a pointer to an +** instance of the [sqlite3_mutex_methods] structure. The +** [sqlite3_mutex_methods] +** structure is filled with the currently defined mutex routines. +** This option can be used to overload the default mutex allocation +** routines with a wrapper used to track mutex usage for performance +** profiling or testing, for example.
+** +**
SQLITE_CONFIG_LOOKASIDE
+**
This option takes two arguments that determine the default +** memory allcation lookaside optimization. The first argument is the +** size of each lookaside buffer slot and the second is the number of +** slots allocated to each database connection.
+** +**
+*/ +#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ +#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ +#define SQLITE_CONFIG_SERIALIZED 3 /* nil */ +#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ +#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ +#define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */ +#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ +#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ +#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ +#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ +#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ +#define SQLITE_CONFIG_CHUNKALLOC 12 /* int threshold */ +#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ + +/* +** CAPI3REF: Configuration Options {H10170} +** EXPERIMENTAL +** +** These constants are the available integer configuration options that +** can be passed as the second argument to the [sqlite3_db_config()] interface. +** +** New configuration options may be added in future releases of SQLite. +** Existing configuration options might be discontinued. Applications +** should check the return code from [sqlite3_db_config()] to make sure that +** the call worked. The [sqlite3_db_config()] interface will return a +** non-zero [error code] if a discontinued or unsupported configuration option +** is invoked. +** +**
+**
SQLITE_DBCONFIG_LOOKASIDE
+**
This option takes three additional arguments that determine the +** [lookaside memory allocator] configuration for the [database connection]. +** The first argument (the third parameter to [sqlite3_db_config()] is a +** pointer to a memory buffer to use for lookaside memory. The first +** argument may be NULL in which case SQLite will allocate the lookaside +** buffer itself using [sqlite3_malloc()]. The second argument is the +** size of each lookaside buffer slot and the third argument is the number of +** slots. The size of the buffer in the first argument must be greater than +** or equal to the product of the second and third arguments.
+** +**
+*/ +#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ + + +/* +** CAPI3REF: Enable Or Disable Extended Result Codes {H12200} ** ** The sqlite3_extended_result_codes() routine enables or disables the -** [SQLITE_IOERR_READ | extended result codes] feature of SQLite. -** The extended result codes are disabled by default for historical -** compatibility. +** [extended result codes] feature of SQLite. The extended result +** codes are disabled by default for historical compatibility considerations. ** ** INVARIANTS: ** -** {F12201} Each new [database connection] has the -** [extended result codes] feature -** disabled by default. +** {H12201} Each new [database connection] shall have the +** [extended result codes] feature disabled by default. ** -** {F12202} The [sqlite3_extended_result_codes(D,F)] interface will enable -** [extended result codes] for the -** [database connection] D if the F parameter -** is true, or disable them if F is false. +** {H12202} The [sqlite3_extended_result_codes(D,F)] interface shall enable +** [extended result codes] for the [database connection] D +** if the F parameter is true, or disable them if F is false. */ SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff); /* -** CAPI3REF: Last Insert Rowid {F12220} +** CAPI3REF: Last Insert Rowid {H12220} ** ** Each entry in an SQLite table has a unique 64-bit signed ** integer key called the "rowid". The rowid is always available @@ -1315,44 +1844,43 @@ SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff); ** is another alias for the rowid. ** ** This routine returns the rowid of the most recent -** successful INSERT into the database from the database connection -** shown in the first argument. If no successful inserts -** have ever occurred on this database connection, zero is returned. -** -** If an INSERT occurs within a trigger, then the rowid of the -** inserted row is returned by this routine as long as the trigger -** is running. But once the trigger terminates, the value returned -** by this routine reverts to the last value inserted before the -** trigger fired. -** -** An INSERT that fails due to a constraint violation is not a -** successful insert and does not change the value returned by this +** successful [INSERT] into the database from the [database connection] +** in the first argument. If no successful [INSERT]s +** have ever occurred on that database connection, zero is returned. +** +** If an [INSERT] occurs within a trigger, then the rowid of the inserted +** row is returned by this routine as long as the trigger is running. +** But once the trigger terminates, the value returned by this routine +** reverts to the last value inserted before the trigger fired. +** +** An [INSERT] that fails due to a constraint violation is not a +** successful [INSERT] and does not change the value returned by this ** routine. Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, ** and INSERT OR ABORT make no changes to the return value of this -** routine when their insertion fails. When INSERT OR REPLACE +** routine when their insertion fails. When INSERT OR REPLACE ** encounters a constraint violation, it does not fail. The ** INSERT continues to completion after deleting rows that caused ** the constraint problem so INSERT OR REPLACE will always change -** the return value of this interface. +** the return value of this interface. ** -** For the purposes of this routine, an insert is considered to +** For the purposes of this routine, an [INSERT] is considered to ** be successful even if it is subsequently rolled back. ** ** INVARIANTS: ** -** {F12221} The [sqlite3_last_insert_rowid()] function returns the -** rowid of the most recent successful insert done -** on the same database connection and within the same -** trigger context, or zero if there have -** been no qualifying inserts on that connection. +** {H12221} The [sqlite3_last_insert_rowid()] function shall return the rowid +** of the most recent successful [INSERT] performed on the same +** [database connection] and within the same or higher level +** trigger context, or zero if there have been no qualifying +** [INSERT] statements. ** -** {F12223} The [sqlite3_last_insert_rowid()] function returns +** {H12223} The [sqlite3_last_insert_rowid()] function shall return the ** same value when called from the same trigger context -** immediately before and after a ROLLBACK. +** immediately before and after a [ROLLBACK]. ** -** LIMITATIONS: +** ASSUMPTIONS: ** -** {U12232} If a separate thread does a new insert on the same +** {A12232} If a separate thread performs a new [INSERT] on the same ** database connection while the [sqlite3_last_insert_rowid()] ** function is running and thus changes the last insert rowid, ** then the value returned by [sqlite3_last_insert_rowid()] is @@ -1362,13 +1890,13 @@ SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff); SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); /* -** CAPI3REF: Count The Number Of Rows Modified {F12240} +** CAPI3REF: Count The Number Of Rows Modified {H12240} ** ** This function returns the number of database rows that were changed ** or inserted or deleted by the most recently completed SQL statement -** on the connection specified by the first parameter. Only -** changes that are directly specified by the INSERT, UPDATE, or -** DELETE statement are counted. Auxiliary changes caused by +** on the [database connection] specified by the first parameter. +** Only changes that are directly specified by the [INSERT], [UPDATE], +** or [DELETE] statement are counted. Auxiliary changes caused by ** triggers are not counted. Use the [sqlite3_total_changes()] function ** to find the total number of changes including changes caused by triggers. ** @@ -1392,84 +1920,93 @@ SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); ** most recent INSERT, UPDATE, or DELETE statement within the same ** trigger context. ** -** So when called from the top level, this function returns the +** Thus, when called from the top level, this function returns the ** number of changes in the most recent INSERT, UPDATE, or DELETE -** that also occurred at the top level. -** Within the body of a trigger, the sqlite3_changes() interface -** can be called to find the number of +** that also occurred at the top level. Within the body of a trigger, +** the sqlite3_changes() interface can be called to find the number of ** changes in the most recently completed INSERT, UPDATE, or DELETE ** statement within the body of the same trigger. -** However, the number returned does not include in changes -** caused by subtriggers since they have their own context. -** -** SQLite implements the command "DELETE FROM table" without -** a WHERE clause by dropping and recreating the table. (This is much -** faster than going through and deleting individual elements from the -** table.) Because of this optimization, the deletions in -** "DELETE FROM table" are not row changes and will not be counted -** by the sqlite3_changes() or [sqlite3_total_changes()] functions. -** To get an accurate count of the number of rows deleted, use -** "DELETE FROM table WHERE 1" instead. +** However, the number returned does not include changes +** caused by subtriggers since those have their own context. +** +** SQLite implements the command "DELETE FROM table" without a WHERE clause +** by dropping and recreating the table. Doing so is much faster than going +** through and deleting individual elements from the table. Because of this +** optimization, the deletions in "DELETE FROM table" are not row changes and +** will not be counted by the sqlite3_changes() or [sqlite3_total_changes()] +** functions, regardless of the number of elements that were originally +** in the table. To get an accurate count of the number of rows deleted, use +** "DELETE FROM table WHERE 1" instead. Or recompile using the +** [SQLITE_OMIT_TRUNCATE_OPTIMIZATION] compile-time option to disable the +** optimization on all queries. ** ** INVARIANTS: ** -** {F12241} The [sqlite3_changes()] function returns the number of +** {H12241} The [sqlite3_changes()] function shall return the number of ** row changes caused by the most recent INSERT, UPDATE, ** or DELETE statement on the same database connection and -** within the same trigger context, or zero if there have +** within the same or higher trigger context, or zero if there have ** not been any qualifying row changes. ** -** LIMITATIONS: +** {H12243} Statements of the form "DELETE FROM tablename" with no +** WHERE clause shall cause subsequent calls to +** [sqlite3_changes()] to return zero, regardless of the +** number of rows originally in the table. ** -** {U12252} If a separate thread makes changes on the same database connection +** ASSUMPTIONS: +** +** {A12252} If a separate thread makes changes on the same database connection ** while [sqlite3_changes()] is running then the value returned -** is unpredictable and unmeaningful. +** is unpredictable and not meaningful. */ SQLITE_API int sqlite3_changes(sqlite3*); /* -** CAPI3REF: Total Number Of Rows Modified {F12260} -*** -** This function returns the number of row changes caused -** by INSERT, UPDATE or DELETE statements since the database handle -** was opened. The count includes all changes from all trigger -** contexts. But the count does not include changes used to -** implement REPLACE constraints, do rollbacks or ABORT processing, -** or DROP table processing. -** The changes -** are counted as soon as the statement that makes them is completed -** (when the statement handle is passed to [sqlite3_reset()] or +** CAPI3REF: Total Number Of Rows Modified {H12260} +** +** This function returns the number of row changes caused by INSERT, +** UPDATE or DELETE statements since the [database connection] was opened. +** The count includes all changes from all trigger contexts. However, +** the count does not include changes used to implement REPLACE constraints, +** do rollbacks or ABORT processing, or DROP table processing. +** The changes are counted as soon as the statement that makes them is +** completed (when the statement handle is passed to [sqlite3_reset()] or ** [sqlite3_finalize()]). ** -** SQLite implements the command "DELETE FROM table" without -** a WHERE clause by dropping and recreating the table. (This is much -** faster than going -** through and deleting individual elements from the table.) Because of -** this optimization, the change count for "DELETE FROM table" will be -** zero regardless of the number of elements that were originally in the -** table. To get an accurate count of the number of rows deleted, use -** "DELETE FROM table WHERE 1" instead. +** SQLite implements the command "DELETE FROM table" without a WHERE clause +** by dropping and recreating the table. (This is much faster than going +** through and deleting individual elements from the table.) Because of this +** optimization, the deletions in "DELETE FROM table" are not row changes and +** will not be counted by the sqlite3_changes() or [sqlite3_total_changes()] +** functions, regardless of the number of elements that were originally +** in the table. To get an accurate count of the number of rows deleted, use +** "DELETE FROM table WHERE 1" instead. Or recompile using the +** [SQLITE_OMIT_TRUNCATE_OPTIMIZATION] compile-time option to disable the +** optimization on all queries. ** ** See also the [sqlite3_changes()] interface. ** ** INVARIANTS: -** -** {F12261} The [sqlite3_total_changes()] returns the total number +** +** {H12261} The [sqlite3_total_changes()] returns the total number ** of row changes caused by INSERT, UPDATE, and/or DELETE ** statements on the same [database connection], in any -** trigger context, since the database connection was -** created. +** trigger context, since the database connection was created. ** -** LIMITATIONS: +** {H12263} Statements of the form "DELETE FROM tablename" with no +** WHERE clause shall not change the value returned +** by [sqlite3_total_changes()]. ** -** {U12264} If a separate thread makes changes on the same database connection -** while [sqlite3_total_changes()] is running then the value -** returned is unpredictable and unmeaningful. +** ASSUMPTIONS: +** +** {A12264} If a separate thread makes changes on the same database connection +** while [sqlite3_total_changes()] is running then the value +** returned is unpredictable and not meaningful. */ SQLITE_API int sqlite3_total_changes(sqlite3*); /* -** CAPI3REF: Interrupt A Long-Running Query {F12270} +** CAPI3REF: Interrupt A Long-Running Query {H12270} ** ** This function causes any pending database operation to abort and ** return at its earliest opportunity. This routine is typically @@ -1479,38 +2016,39 @@ SQLITE_API int sqlite3_total_changes(sqlite3*); ** ** It is safe to call this routine from a thread different from the ** thread that is currently running the database operation. But it -** is not safe to call this routine with a database connection that +** is not safe to call this routine with a [database connection] that ** is closed or might close before sqlite3_interrupt() returns. ** -** If an SQL is very nearly finished at the time when sqlite3_interrupt() -** is called, then it might not have an opportunity to be interrupted. -** It might continue to completion. -** An SQL operation that is interrupted will return -** [SQLITE_INTERRUPT]. If the interrupted SQL operation is an -** INSERT, UPDATE, or DELETE that is inside an explicit transaction, -** then the entire transaction will be rolled back automatically. +** If an SQL operation is very nearly finished at the time when +** sqlite3_interrupt() is called, then it might not have an opportunity +** to be interrupted and might continue to completion. +** +** An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. +** If the interrupted SQL operation is an INSERT, UPDATE, or DELETE +** that is inside an explicit transaction, then the entire transaction +** will be rolled back automatically. +** ** A call to sqlite3_interrupt() has no effect on SQL statements ** that are started after sqlite3_interrupt() returns. ** ** INVARIANTS: ** -** {F12271} The [sqlite3_interrupt()] interface will force all running +** {H12271} The [sqlite3_interrupt()] interface will force all running ** SQL statements associated with the same database connection -** to halt after processing at most one additional row of -** data. +** to halt after processing at most one additional row of data. ** -** {F12272} Any SQL statement that is interrupted by [sqlite3_interrupt()] +** {H12272} Any SQL statement that is interrupted by [sqlite3_interrupt()] ** will return [SQLITE_INTERRUPT]. ** -** LIMITATIONS: +** ASSUMPTIONS: ** -** {U12279} If the database connection closes while [sqlite3_interrupt()] +** {A12279} If the database connection closes while [sqlite3_interrupt()] ** is running then bad things will likely happen. */ SQLITE_API void sqlite3_interrupt(sqlite3*); /* -** CAPI3REF: Determine If An SQL Statement Is Complete {F10510} +** CAPI3REF: Determine If An SQL Statement Is Complete {H10510} ** ** These routines are useful for command-line input to determine if the ** currently entered text seems to form complete a SQL statement or @@ -1523,54 +2061,56 @@ SQLITE_API void sqlite3_interrupt(sqlite3*); ** independent tokens (they are part of the token in which they are ** embedded) and thus do not count as a statement terminator. ** -** These routines do not parse the SQL and -** so will not detect syntactically incorrect SQL. +** These routines do not parse the SQL statements thus +** will not detect syntactically incorrect SQL. ** ** INVARIANTS: ** -** {F10511} The sqlite3_complete() and sqlite3_complete16() functions -** return true (non-zero) if and only if the last -** non-whitespace token in their input is a semicolon that -** is not in between the BEGIN and END of a CREATE TRIGGER -** statement. +** {H10511} A successful evaluation of [sqlite3_complete()] or +** [sqlite3_complete16()] functions shall +** return a numeric 1 if and only if the last non-whitespace +** token in their input is a semicolon that is not in between +** the BEGIN and END of a CREATE TRIGGER statement. ** -** LIMITATIONS: +** {H10512} If a memory allocation error occurs during an invocation +** of [sqlite3_complete()] or [sqlite3_complete16()] then the +** routine shall return [SQLITE_NOMEM]. ** -** {U10512} The input to sqlite3_complete() must be a zero-terminated +** ASSUMPTIONS: +** +** {A10512} The input to [sqlite3_complete()] must be a zero-terminated ** UTF-8 string. ** -** {U10513} The input to sqlite3_complete16() must be a zero-terminated +** {A10513} The input to [sqlite3_complete16()] must be a zero-terminated ** UTF-16 string in native byte order. */ SQLITE_API int sqlite3_complete(const char *sql); SQLITE_API int sqlite3_complete16(const void *sql); /* -** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {F12310} -** -** This routine identifies a callback function that might be -** invoked whenever an attempt is made to open a database table -** that another thread or process has locked. -** If the busy callback is NULL, then [SQLITE_BUSY] -** or [SQLITE_IOERR_BLOCKED] -** is returned immediately upon encountering the lock. -** If the busy callback is not NULL, then the -** callback will be invoked with two arguments. The -** first argument to the handler is a copy of the void* pointer which -** is the third argument to this routine. The second argument to -** the handler is the number of times that the busy handler has -** been invoked for this locking event. If the +** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {H12310} +** +** This routine sets a callback function that might be invoked whenever +** an attempt is made to open a database table that another thread +** or process has locked. +** +** If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] +** is returned immediately upon encountering the lock. If the busy callback +** is not NULL, then the callback will be invoked with two arguments. +** +** The first argument to the handler is a copy of the void* pointer which +** is the third argument to sqlite3_busy_handler(). The second argument to +** the handler callback is the number of times that the busy handler has +** been invoked for this locking event. If the ** busy callback returns 0, then no additional attempts are made to ** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned. ** If the callback returns non-zero, then another attempt ** is made to open the database for reading and the cycle repeats. ** -** The presence of a busy handler does not guarantee that -** it will be invoked when there is lock contention. -** If SQLite determines that invoking the busy handler could result in -** a deadlock, it will go ahead and return [SQLITE_BUSY] or -** [SQLITE_IOERR_BLOCKED] instead of invoking the -** busy handler. +** The presence of a busy handler does not guarantee that it will be invoked +** when there is lock contention. If SQLite determines that invoking the busy +** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] +** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler. ** Consider a scenario where one process is holding a read lock that ** it is trying to promote to a reserved lock and ** a second process is holding a reserved lock that it is trying @@ -1595,82 +2135,86 @@ SQLITE_API int sqlite3_complete16(const void *sql); ** code is promoted from the relatively benign [SQLITE_BUSY] to ** the more severe [SQLITE_IOERR_BLOCKED]. This error code promotion ** forces an automatic rollback of the changes. See the -** +** ** CorruptionFollowingBusyError wiki page for a discussion of why ** this is important. -** -** There can only be a single busy handler defined for each database -** connection. Setting a new busy handler clears any previous one. -** Note that calling [sqlite3_busy_timeout()] will also set or clear -** the busy handler. ** +** There can only be a single busy handler defined for each +** [database connection]. Setting a new busy handler clears any +** previously set handler. Note that calling [sqlite3_busy_timeout()] +** will also set or clear the busy handler. +** +** The busy callback should not take any actions which modify the +** database connection that invoked the busy handler. Any such actions +** result in undefined behavior. +** ** INVARIANTS: ** -** {F12311} The [sqlite3_busy_handler()] function replaces the busy handler -** callback in the database connection identified by the 1st -** parameter with a new busy handler identified by the 2nd and 3rd -** parameters. +** {H12311} The [sqlite3_busy_handler(D,C,A)] function shall replace +** busy callback in the [database connection] D with a new +** a new busy handler C and application data pointer A. ** -** {F12312} The default busy handler for new database connections is NULL. +** {H12312} Newly created [database connections] shall have a busy +** handler of NULL. ** -** {F12314} When two or more database connection share a common cache, +** {H12314} When two or more [database connections] share a +** [sqlite3_enable_shared_cache | common cache], ** the busy handler for the database connection currently using -** the cache is invoked when the cache encounters a lock. +** the cache shall be invoked when the cache encounters a lock. ** -** {F12316} If a busy handler callback returns zero, then the SQLite -** interface that provoked the locking event will return -** [SQLITE_BUSY]. +** {H12316} If a busy handler callback returns zero, then the SQLite interface +** that provoked the locking event shall return [SQLITE_BUSY]. ** -** {F12318} SQLite will invokes the busy handler with two argument which +** {H12318} SQLite shall invokes the busy handler with two arguments which ** are a copy of the pointer supplied by the 3rd parameter to ** [sqlite3_busy_handler()] and a count of the number of prior ** invocations of the busy handler for the same locking event. ** -** LIMITATIONS: +** ASSUMPTIONS: ** -** {U12319} A busy handler should not call close the database connection -** or prepared statement that invoked the busy handler. +** {A12319} A busy handler must not close the database connection +** or [prepared statement] that invoked the busy handler. */ SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*); /* -** CAPI3REF: Set A Busy Timeout {F12340} +** CAPI3REF: Set A Busy Timeout {H12340} ** -** This routine sets a [sqlite3_busy_handler | busy handler] -** that sleeps for a while when a -** table is locked. The handler will sleep multiple times until -** at least "ms" milliseconds of sleeping have been done. {F12343} After -** "ms" milliseconds of sleeping, the handler returns 0 which -** causes [sqlite3_step()] to return [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]. +** This routine sets a [sqlite3_busy_handler | busy handler] that sleeps +** for a specified amount of time when a table is locked. The handler +** will sleep multiple times until at least "ms" milliseconds of sleeping +** have accumulated. {H12343} After "ms" milliseconds of sleeping, +** the handler returns 0 which causes [sqlite3_step()] to return +** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]. ** ** Calling this routine with an argument less than or equal to zero ** turns off all busy handlers. ** -** There can only be a single busy handler for a particular database -** connection. If another busy handler was defined -** (using [sqlite3_busy_handler()]) prior to calling +** There can only be a single busy handler for a particular +** [database connection] any any given moment. If another busy handler +** was defined (using [sqlite3_busy_handler()]) prior to calling ** this routine, that other busy handler is cleared. ** ** INVARIANTS: ** -** {F12341} The [sqlite3_busy_timeout()] function overrides any prior +** {H12341} The [sqlite3_busy_timeout()] function shall override any prior ** [sqlite3_busy_timeout()] or [sqlite3_busy_handler()] setting -** on the same database connection. +** on the same [database connection]. ** -** {F12343} If the 2nd parameter to [sqlite3_busy_timeout()] is less than -** or equal to zero, then the busy handler is cleared so that +** {H12343} If the 2nd parameter to [sqlite3_busy_timeout()] is less than +** or equal to zero, then the busy handler shall be cleared so that ** all subsequent locking events immediately return [SQLITE_BUSY]. ** -** {F12344} If the 2nd parameter to [sqlite3_busy_timeout()] is a positive -** number N, then a busy handler is set that repeatedly calls -** the xSleep() method in the VFS interface until either the -** lock clears or until the cumulative sleep time reported back -** by xSleep() exceeds N milliseconds. +** {H12344} If the 2nd parameter to [sqlite3_busy_timeout()] is a positive +** number N, then a busy handler shall be set that repeatedly calls +** the xSleep() method in the [sqlite3_vfs | VFS interface] until +** either the lock clears or until the cumulative sleep time +** reported back by xSleep() exceeds N milliseconds. */ SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); /* -** CAPI3REF: Convenience Routines For Running Queries {F12370} +** CAPI3REF: Convenience Routines For Running Queries {H12370} ** ** Definition: A result table is memory data structure created by the ** [sqlite3_get_table()] interface. A result table records the @@ -1681,16 +2225,14 @@ SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); ** numbers are obtained separately. Let N be the number of rows ** and M be the number of columns. ** -** A result table is an array of pointers to zero-terminated -** UTF-8 strings. There are (N+1)*M elements in the array. -** The first M pointers point to zero-terminated strings that -** contain the names of the columns. -** The remaining entries all point to query results. NULL -** values are give a NULL pointer. All other values are in -** their UTF-8 zero-terminated string representation as returned by -** [sqlite3_column_text()]. +** A result table is an array of pointers to zero-terminated UTF-8 strings. +** There are (N+1)*M elements in the array. The first M pointers point +** to zero-terminated strings that contain the names of the columns. +** The remaining entries all point to query results. NULL values result +** in NULL pointers. All other values are in their UTF-8 zero-terminated +** string representation as returned by [sqlite3_column_text()]. ** -** A result table might consists of one or more memory allocations. +** A result table might consist of one or more memory allocations. ** It is not safe to pass a result table directly to [sqlite3_free()]. ** A result table should be deallocated using [sqlite3_free_table()]. ** @@ -1725,11 +2267,11 @@ SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); ** string of its 2nd parameter. It returns a result table to the ** pointer given in its 3rd parameter. ** -** After the calling function has finished using the result, it should -** pass the pointer to the result table to sqlite3_free_table() in order to -** release the memory that was malloc-ed. Because of the way the +** After the calling function has finished using the result, it should +** pass the pointer to the result table to sqlite3_free_table() in order to +** release the memory that was malloced. Because of the way the ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling -** function must not try to call [sqlite3_free()] directly. Only +** function must not try to call [sqlite3_free()] directly. Only ** [sqlite3_free_table()] is able to release the memory properly and safely. ** ** The sqlite3_get_table() interface is implemented as a wrapper around @@ -1737,43 +2279,53 @@ SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); ** to any internal data structures of SQLite. It uses only the public ** interface defined here. As a consequence, errors that occur in the ** wrapper layer outside of the internal [sqlite3_exec()] call are not -** reflected in subsequent calls to [sqlite3_errcode()] or -** [sqlite3_errmsg()]. +** reflected in subsequent calls to [sqlite3_errcode()] or [sqlite3_errmsg()]. ** ** INVARIANTS: ** -** {F12371} If a [sqlite3_get_table()] fails a memory allocation, then -** it frees the result table under construction, aborts the -** query in process, skips any subsequent queries, sets the -** *resultp output pointer to NULL and returns [SQLITE_NOMEM]. -** -** {F12373} If the ncolumn parameter to [sqlite3_get_table()] is not NULL -** then [sqlite3_get_table()] write the number of columns in the -** result set of the query into *ncolumn if the query is -** successful (if the function returns SQLITE_OK). +** {H12371} If a [sqlite3_get_table()] fails a memory allocation, then +** it shall free the result table under construction, abort the +** query in process, skip any subsequent queries, set the +** *pazResult output pointer to NULL and return [SQLITE_NOMEM]. +** +** {H12373} If the pnColumn parameter to [sqlite3_get_table()] is not NULL +** then a successful invocation of [sqlite3_get_table()] shall +** write the number of columns in the +** result set of the query into *pnColumn. +** +** {H12374} If the pnRow parameter to [sqlite3_get_table()] is not NULL +** then a successful invocation of [sqlite3_get_table()] shall +** writes the number of rows in the +** result set of the query into *pnRow. +** +** {H12376} A successful invocation of [sqlite3_get_table()] that computes +** N rows of result with C columns per row shall make *pazResult +** point to an array of pointers to (N+1)*C strings where the first +** C strings are column names as obtained from +** [sqlite3_column_name()] and the rest are column result values +** obtained from [sqlite3_column_text()]. ** -** {F12374} If the nrow parameter to [sqlite3_get_table()] is not NULL -** then [sqlite3_get_table()] write the number of rows in the -** result set of the query into *nrow if the query is -** successful (if the function returns SQLITE_OK). +** {H12379} The values in the pazResult array returned by [sqlite3_get_table()] +** shall remain valid until cleared by [sqlite3_free_table()]. ** -** {F12376} The [sqlite3_get_table()] function sets its *ncolumn value -** to the number of columns in the result set of the query in the -** sql parameter, or to zero if the query in sql has an empty -** result set. +** {H12382} When an error occurs during evaluation of [sqlite3_get_table()] +** the function shall set *pazResult to NULL, write an error message +** into memory obtained from [sqlite3_malloc()], make +** **pzErrmsg point to that error message, and return a +** appropriate [error code]. */ SQLITE_API int sqlite3_get_table( - sqlite3*, /* An open database */ - const char *sql, /* SQL to be evaluated */ - char ***pResult, /* Results of the query */ - int *nrow, /* Number of result rows written here */ - int *ncolumn, /* Number of result columns written here */ - char **errmsg /* Error msg written here */ + sqlite3 *db, /* An open database */ + const char *zSql, /* SQL to be evaluated */ + char ***pazResult, /* Results of the query */ + int *pnRow, /* Number of result rows written here */ + int *pnColumn, /* Number of result columns written here */ + char **pzErrmsg /* Error msg written here */ ); SQLITE_API void sqlite3_free_table(char **result); /* -** CAPI3REF: Formatted String Printing Functions {F17400} +** CAPI3REF: Formatted String Printing Functions {H17400} ** ** These routines are workalikes of the "printf()" family of functions ** from the standard C library. @@ -1781,7 +2333,7 @@ SQLITE_API void sqlite3_free_table(char **result); ** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their ** results into memory obtained from [sqlite3_malloc()]. ** The strings returned by these two routines should be -** released by [sqlite3_free()]. Both routines return a +** released by [sqlite3_free()]. Both routines return a ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough ** memory to hold the resulting string. ** @@ -1806,7 +2358,7 @@ SQLITE_API void sqlite3_free_table(char **result); ** ** These routines all implement some additional formatting ** options that are useful for constructing SQL statements. -** All of the usual printf formatting options apply. In addition, there +** All of the usual printf() formatting options apply. In addition, there ** is are "%q", "%Q", and "%z" options. ** ** The %q option works like %s in that it substitutes a null-terminated @@ -1815,7 +2367,7 @@ SQLITE_API void sqlite3_free_table(char **result); ** character it escapes that character and allows it to be inserted into ** the string. ** -** For example, so some string variable contains text as follows: +** For example, assume the string variable zText contains text as follows: ** ** 
 **  char *zText = "It's a happy day!";
@@ -1843,14 +2395,13 @@ SQLITE_API void sqlite3_free_table(char **result);
 **  INSERT INTO table1 VALUES('It's a happy day!');
 **
** -** This second example is an SQL syntax error. As a general rule you -** should always use %q instead of %s when inserting text into a string -** literal. +** This second example is an SQL syntax error. As a general rule you should +** always use %q instead of %s when inserting text into a string literal. ** ** The %Q option works like %q except it also adds single quotes around -** the outside of the total string. Or if the parameter in the argument -** list is a NULL pointer, %Q substitutes the text "NULL" (without single -** quotes) in place of the %Q option. {END} So, for example, one could say: +** the outside of the total string. Additionally, if the parameter in the +** argument list is a NULL pointer, %Q substitutes the text "NULL" (without +** single quotes) in place of the %Q option. So, for example, one could say: ** ** 
 **  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
@@ -1867,33 +2418,32 @@ SQLITE_API void sqlite3_free_table(char **result);
 **
 ** INVARIANTS:
 **
-** {F17403}  The [sqlite3_mprintf()] and [sqlite3_vmprintf()] interfaces
+** {H17403}  The [sqlite3_mprintf()] and [sqlite3_vmprintf()] interfaces
 **           return either pointers to zero-terminated UTF-8 strings held in
 **           memory obtained from [sqlite3_malloc()] or NULL pointers if
 **           a call to [sqlite3_malloc()] fails.
 **
-** {F17406}  The [sqlite3_snprintf()] interface writes a zero-terminated
+** {H17406}  The [sqlite3_snprintf()] interface writes a zero-terminated
 **           UTF-8 string into the buffer pointed to by the second parameter
 **           provided that the first parameter is greater than zero.
 **
-** {F17407}  The [sqlite3_snprintf()] interface does not writes slots of
+** {H17407}  The [sqlite3_snprintf()] interface does not write slots of
 **           its output buffer (the second parameter) outside the range
 **           of 0 through N-1 (where N is the first parameter)
 **           regardless of the length of the string
 **           requested by the format specification.
-**   
 */
 SQLITE_API char *sqlite3_mprintf(const char*,...);
 SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
 SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
 
 /*
-** CAPI3REF: Memory Allocation Subsystem {F17300}
+** CAPI3REF: Memory Allocation Subsystem {H17300} 
 **
 ** The SQLite core  uses these three routines for all of its own
 ** internal memory allocation needs. "Core" in the previous sentence
 ** does not include operating-system specific VFS implementation.  The
-** windows VFS uses native malloc and free for some operations.
+** Windows VFS uses native malloc() and free() for some operations.
 **
 ** The sqlite3_malloc() routine returns a pointer to a block
 ** of memory at least N bytes in length, where N is the parameter.
@@ -1922,7 +2472,7 @@ SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
 ** If the second parameter to sqlite3_realloc() is zero or
 ** negative then the behavior is exactly the same as calling
 ** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
-** Sqlite3_realloc() returns a pointer to a memory allocation
+** sqlite3_realloc() returns a pointer to a memory allocation
 ** of at least N bytes in size or NULL if sufficient memory is unavailable.
 ** If M is the size of the prior allocation, then min(N,M) bytes
 ** of the prior allocation are copied into the beginning of buffer returned
@@ -1933,137 +2483,157 @@ SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
 ** The memory returned by sqlite3_malloc() and sqlite3_realloc()
 ** is always aligned to at least an 8 byte boundary. {END}
 **
-** The default implementation
-** of the memory allocation subsystem uses the malloc(), realloc()
-** and free() provided by the standard C library. {F17382} However, if 
-** SQLite is compiled with the following C preprocessor macro
-**
-** 
 SQLITE_MEMORY_SIZE=NNN 

-**
-** where NNN is an integer, then SQLite create a static
-** array of at least NNN bytes in size and use that array
-** for all of its dynamic memory allocation needs. {END}  Additional
-** memory allocator options may be added in future releases.
+** The default implementation of the memory allocation subsystem uses
+** the malloc(), realloc() and free() provided by the standard C library.
+** {H17382} However, if SQLite is compiled with the
+** SQLITE_MEMORY_SIZE=NNN C preprocessor macro (where NNN
+** is an integer), then SQLite create a static array of at least
+** NNN bytes in size and uses that array for all of its dynamic
+** memory allocation needs. {END}  Additional memory allocator options
+** may be added in future releases.
 **
 ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
 ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
 ** implementation of these routines to be omitted.  That capability
-** is no longer provided.  Only built-in memory allocators can be
-** used.
+** is no longer provided.  Only built-in memory allocators can be used.
 **
-** The windows OS interface layer calls
+** The Windows OS interface layer calls
 ** the system malloc() and free() directly when converting
 ** filenames between the UTF-8 encoding used by SQLite
-** and whatever filename encoding is used by the particular windows
+** and whatever filename encoding is used by the particular Windows
 ** installation.  Memory allocation errors are detected, but
 ** they are reported back as [SQLITE_CANTOPEN] or
 ** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
 **
 ** INVARIANTS:
 **
-** {F17303}  The [sqlite3_malloc(N)] interface returns either a pointer to 
-**           newly checked-out block of at least N bytes of memory
-**           that is 8-byte aligned, 
-**           or it returns NULL if it is unable to fulfill the request.
+** {H17303}  The [sqlite3_malloc(N)] interface returns either a pointer to
+**           a newly checked-out block of at least N bytes of memory
+**           that is 8-byte aligned, or it returns NULL if it is unable
+**           to fulfill the request.
 **
-** {F17304}  The [sqlite3_malloc(N)] interface returns a NULL pointer if
+** {H17304}  The [sqlite3_malloc(N)] interface returns a NULL pointer if
 **           N is less than or equal to zero.
 **
-** {F17305}  The [sqlite3_free(P)] interface releases memory previously
+** {H17305}  The [sqlite3_free(P)] interface releases memory previously
 **           returned from [sqlite3_malloc()] or [sqlite3_realloc()],
 **           making it available for reuse.
 **
-** {F17306}  A call to [sqlite3_free(NULL)] is a harmless no-op.
+** {H17306}  A call to [sqlite3_free(NULL)] is a harmless no-op.
 **
-** {F17310}  A call to [sqlite3_realloc(0,N)] is equivalent to a call
+** {H17310}  A call to [sqlite3_realloc(0,N)] is equivalent to a call
 **           to [sqlite3_malloc(N)].
 **
-** {F17312}  A call to [sqlite3_realloc(P,0)] is equivalent to a call
+** {H17312}  A call to [sqlite3_realloc(P,0)] is equivalent to a call
 **           to [sqlite3_free(P)].
 **
-** {F17315}  The SQLite core uses [sqlite3_malloc()], [sqlite3_realloc()],
+** {H17315}  The SQLite core uses [sqlite3_malloc()], [sqlite3_realloc()],
 **           and [sqlite3_free()] for all of its memory allocation and
 **           deallocation needs.
 **
-** {F17318}  The [sqlite3_realloc(P,N)] interface returns either a pointer
+** {H17318}  The [sqlite3_realloc(P,N)] interface returns either a pointer
 **           to a block of checked-out memory of at least N bytes in size
 **           that is 8-byte aligned, or a NULL pointer.
 **
-** {F17321}  When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
-**           copies the first K bytes of content from P into the newly allocated
-**           where K is the lessor of N and the size of the buffer P.
+** {H17321}  When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
+**           copies the first K bytes of content from P into the newly
+**           allocated block, where K is the lesser of N and the size of
+**           the buffer P.
 **
-** {F17322}  When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
+** {H17322}  When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
 **           releases the buffer P.
 **
-** {F17323}  When [sqlite3_realloc(P,N)] returns NULL, the buffer P is
+** {H17323}  When [sqlite3_realloc(P,N)] returns NULL, the buffer P is
 **           not modified or released.
 **
-** LIMITATIONS:
+** ASSUMPTIONS:
 **
-** {U17350}  The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
-**           must be either NULL or else a pointer obtained from a prior
-**           invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that has
-**           not been released.
+** {A17350}  The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
+**           must be either NULL or else pointers obtained from a prior
+**           invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
+**           not yet been released.
 **
-** {U17351}  The application must not read or write any part of 
+** {A17351}  The application must not read or write any part of
 **           a block of memory after it has been released using
 **           [sqlite3_free()] or [sqlite3_realloc()].
-**
 */
 SQLITE_API void *sqlite3_malloc(int);
 SQLITE_API void *sqlite3_realloc(void*, int);
 SQLITE_API void sqlite3_free(void*);
 
 /*
-** CAPI3REF: Memory Allocator Statistics {F17370}
+** CAPI3REF: Memory Allocator Statistics {H17370} 
 **
 ** SQLite provides these two interfaces for reporting on the status
 ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
-** the memory allocation subsystem included within the SQLite.
+** routines, which form the built-in memory allocation subsystem.
 **
 ** INVARIANTS:
 **
-** {F17371} The [sqlite3_memory_used()] routine returns the
-**          number of bytes of memory currently outstanding 
-**          (malloced but not freed).
+** {H17371} The [sqlite3_memory_used()] routine returns the number of bytes
+**          of memory currently outstanding (malloced but not freed).
 **
-** {F17373} The [sqlite3_memory_highwater()] routine returns the maximum
-**          value of [sqlite3_memory_used()] 
-**          since the highwater mark was last reset.
+** {H17373} The [sqlite3_memory_highwater()] routine returns the maximum
+**          value of [sqlite3_memory_used()] since the high-water mark
+**          was last reset.
 **
-** {F17374} The values returned by [sqlite3_memory_used()] and
+** {H17374} The values returned by [sqlite3_memory_used()] and
 **          [sqlite3_memory_highwater()] include any overhead
 **          added by SQLite in its implementation of [sqlite3_malloc()],
 **          but not overhead added by the any underlying system library
 **          routines that [sqlite3_malloc()] may call.
-** 
-** {F17375} The memory highwater mark is reset to the current value of
+**
+** {H17375} The memory high-water mark is reset to the current value of
 **          [sqlite3_memory_used()] if and only if the parameter to
 **          [sqlite3_memory_highwater()] is true.  The value returned
-**          by [sqlite3_memory_highwater(1)] is the highwater mark
+**          by [sqlite3_memory_highwater(1)] is the high-water mark
 **          prior to the reset.
 */
 SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
 SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
 
 /*
-** CAPI3REF: Compile-Time Authorization Callbacks {F12500}
+** CAPI3REF: Pseudo-Random Number Generator {H17390} 
+**
+** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
+** select random ROWIDs when inserting new records into a table that
+** already uses the largest possible ROWID.  The PRNG is also used for
+** the build-in random() and randomblob() SQL functions.  This interface allows
+** applications to access the same PRNG for other purposes.
+**
+** A call to this routine stores N bytes of randomness into buffer P.
+**
+** The first time this routine is invoked (either internally or by
+** the application) the PRNG is seeded using randomness obtained
+** from the xRandomness method of the default [sqlite3_vfs] object.
+** On all subsequent invocations, the pseudo-randomness is generated
+** internally and without recourse to the [sqlite3_vfs] xRandomness
+** method.
+**
+** INVARIANTS:
+**
+** {H17392} The [sqlite3_randomness(N,P)] interface writes N bytes of
+**          high-quality pseudo-randomness into buffer P.
+*/
+SQLITE_API void sqlite3_randomness(int N, void *P);
+
+/*
+** CAPI3REF: Compile-Time Authorization Callbacks {H12500} 
 **
 ** This routine registers a authorizer callback with a particular
-** database connection, supplied in the first argument.
+** [database connection], supplied in the first argument.
 ** The authorizer callback is invoked as SQL statements are being compiled
 ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
 ** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()].  At various
 ** points during the compilation process, as logic is being created
 ** to perform various actions, the authorizer callback is invoked to
 ** see if those actions are allowed.  The authorizer callback should
-** return SQLITE_OK to allow the action, [SQLITE_IGNORE] to disallow the
+** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
 ** specific action but allow the SQL statement to continue to be
 ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
-** rejected with an error.   If the authorizer callback returns
+** rejected with an error.  If the authorizer callback returns
 ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
-** then [sqlite3_prepare_v2()] or equivalent call that triggered
+** then the [sqlite3_prepare_v2()] or equivalent call that triggered
 ** the authorizer will fail with an error message.
 **
 ** When the callback returns [SQLITE_OK], that means the operation
@@ -2071,92 +2641,106 @@ SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
 ** [sqlite3_prepare_v2()] or equivalent call that triggered the
 ** authorizer will fail with an error message explaining that
 ** access is denied.  If the authorizer code is [SQLITE_READ]
-** and the callback returns [SQLITE_IGNORE] then the prepared
-** statement is constructed to insert a NULL value in place of
-** the table column that would have
+** and the callback returns [SQLITE_IGNORE] then the
+** [prepared statement] statement is constructed to substitute
+** a NULL value in place of the table column that would have
 ** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
 ** return can be used to deny an untrusted user access to individual
 ** columns of a table.
 **
-** The first parameter to the authorizer callback is a copy of
-** the third parameter to the sqlite3_set_authorizer() interface.
-** The second parameter to the callback is an integer 
-** [SQLITE_COPY | action code] that specifies the particular action
-** to be authorized. The third through sixth
-** parameters to the callback are zero-terminated strings that contain 
-** additional details about the action to be authorized.
-**
-** An authorizer is used when preparing SQL statements from an untrusted
-** source, to ensure that the SQL statements do not try to access data
-** that they are not allowed to see, or that they do not try to
-** execute malicious statements that damage the database.  For
+** The first parameter to the authorizer callback is a copy of the third
+** parameter to the sqlite3_set_authorizer() interface. The second parameter
+** to the callback is an integer [SQLITE_COPY | action code] that specifies
+** the particular action to be authorized. The third through sixth parameters
+** to the callback are zero-terminated strings that contain additional
+** details about the action to be authorized.
+**
+** An authorizer is used when [sqlite3_prepare | preparing]
+** SQL statements from an untrusted source, to ensure that the SQL statements
+** do not try to access data they are not allowed to see, or that they do not
+** try to execute malicious statements that damage the database.  For
 ** example, an application may allow a user to enter arbitrary
 ** SQL queries for evaluation by a database.  But the application does
 ** not want the user to be able to make arbitrary changes to the
 ** database.  An authorizer could then be put in place while the
-** user-entered SQL is being prepared that disallows everything
-** except SELECT statements.  
+** user-entered SQL is being [sqlite3_prepare | prepared] that
+** disallows everything except [SELECT] statements.
+**
+** Applications that need to process SQL from untrusted sources
+** might also consider lowering resource limits using [sqlite3_limit()]
+** and limiting database size using the [max_page_count] [PRAGMA]
+** in addition to using an authorizer.
 **
 ** Only a single authorizer can be in place on a database connection
 ** at a time.  Each call to sqlite3_set_authorizer overrides the
 ** previous call.  Disable the authorizer by installing a NULL callback.
 ** The authorizer is disabled by default.
 **
-** Note that the authorizer callback is invoked only during 
+** The authorizer callback must not do anything that will modify
+** the database connection that invoked the authorizer callback.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
+** When [sqlite3_prepare_v2()] is used to prepare a statement, the
+** statement might be reprepared during [sqlite3_step()] due to a 
+** schema change.  Hence, the application should ensure that the
+** correct authorizer callback remains in place during the [sqlite3_step()].
+**
+** Note that the authorizer callback is invoked only during
 ** [sqlite3_prepare()] or its variants.  Authorization is not
 ** performed during statement evaluation in [sqlite3_step()].
 **
 ** INVARIANTS:
 **
-** {F12501} The [sqlite3_set_authorizer(D,...)] interface registers a
+** {H12501} The [sqlite3_set_authorizer(D,...)] interface registers a
 **          authorizer callback with database connection D.
 **
-** {F12502} The authorizer callback is invoked as SQL statements are
-**          being compiled
+** {H12502} The authorizer callback is invoked as SQL statements are
+**          being parseed and compiled.
 **
-** {F12503} If the authorizer callback returns any value other than
-**          [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] then
-**          the [sqlite3_prepare_v2()] or equivalent call that caused
+** {H12503} If the authorizer callback returns any value other than
+**          [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY], then
+**          the application interface call that caused
 **          the authorizer callback to run shall fail with an
 **          [SQLITE_ERROR] error code and an appropriate error message.
 **
-** {F12504} When the authorizer callback returns [SQLITE_OK], the operation
-**          described is coded normally.
+** {H12504} When the authorizer callback returns [SQLITE_OK], the operation
+**          described is processed normally.
 **
-** {F12505} When the authorizer callback returns [SQLITE_DENY], the
-**          [sqlite3_prepare_v2()] or equivalent call that caused the
+** {H12505} When the authorizer callback returns [SQLITE_DENY], the
+**          application interface call that caused the
 **          authorizer callback to run shall fail
 **          with an [SQLITE_ERROR] error code and an error message
 **          explaining that access is denied.
 **
-** {F12506} If the authorizer code (the 2nd parameter to the authorizer
+** {H12506} If the authorizer code (the 2nd parameter to the authorizer
 **          callback) is [SQLITE_READ] and the authorizer callback returns
-**          [SQLITE_IGNORE] then the prepared statement is constructed to
+**          [SQLITE_IGNORE], then the prepared statement is constructed to
 **          insert a NULL value in place of the table column that would have
 **          been read if [SQLITE_OK] had been returned.
 **
-** {F12507} If the authorizer code (the 2nd parameter to the authorizer
+** {H12507} If the authorizer code (the 2nd parameter to the authorizer
 **          callback) is anything other than [SQLITE_READ], then
-**          a return of [SQLITE_IGNORE] has the same effect as [SQLITE_DENY]. 
+**          a return of [SQLITE_IGNORE] has the same effect as [SQLITE_DENY].
 **
-** {F12510} The first parameter to the authorizer callback is a copy of
+** {H12510} The first parameter to the authorizer callback is a copy of
 **          the third parameter to the [sqlite3_set_authorizer()] interface.
 **
-** {F12511} The second parameter to the callback is an integer 
+** {H12511} The second parameter to the callback is an integer
 **          [SQLITE_COPY | action code] that specifies the particular action
 **          to be authorized.
 **
-** {F12512} The third through sixth parameters to the callback are
-**          zero-terminated strings that contain 
+** {H12512} The third through sixth parameters to the callback are
+**          zero-terminated strings that contain
 **          additional details about the action to be authorized.
 **
-** {F12520} Each call to [sqlite3_set_authorizer()] overrides the
+** {H12520} Each call to [sqlite3_set_authorizer()] overrides
 **          any previously installed authorizer.
 **
-** {F12521} A NULL authorizer means that no authorization
+** {H12521} A NULL authorizer means that no authorization
 **          callback is invoked.
 **
-** {F12522} The default authorizer is NULL.
+** {H12522} The default authorizer is NULL.
 */
 SQLITE_API int sqlite3_set_authorizer(
   sqlite3*,
@@ -2165,7 +2749,7 @@ SQLITE_API int sqlite3_set_authorizer(
 );
 
 /*
-** CAPI3REF: Authorizer Return Codes {F12590}
+** CAPI3REF: Authorizer Return Codes {H12590} 
 **
 ** The [sqlite3_set_authorizer | authorizer callback function] must
 ** return either [SQLITE_OK] or one of these two constants in order
@@ -2177,44 +2761,44 @@ SQLITE_API int sqlite3_set_authorizer(
 #define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
 
 /*
-** CAPI3REF: Authorizer Action Codes {F12550}
+** CAPI3REF: Authorizer Action Codes {H12550} 
 **
 ** The [sqlite3_set_authorizer()] interface registers a callback function
-** that is invoked to authorizer certain SQL statement actions.  The
+** that is invoked to authorize certain SQL statement actions.  The
 ** second parameter to the callback is an integer code that specifies
 ** what action is being authorized.  These are the integer action codes that
 ** the authorizer callback may be passed.
 **
-** These action code values signify what kind of operation is to be 
+** These action code values signify what kind of operation is to be
 ** authorized.  The 3rd and 4th parameters to the authorization
 ** callback function will be parameters or NULL depending on which of these
 ** codes is used as the second parameter.  The 5th parameter to the
-** authorizer callback is the name of the database ("main", "temp", 
+** authorizer callback is the name of the database ("main", "temp",
 ** etc.) if applicable.  The 6th parameter to the authorizer callback
 ** is the name of the inner-most trigger or view that is responsible for
-** the access attempt or NULL if this access attempt is directly from 
+** the access attempt or NULL if this access attempt is directly from
 ** top-level SQL code.
 **
 ** INVARIANTS:
 **
-** {F12551} The second parameter to an 
-**          [sqlite3_set_authorizer | authorizer callback is always an integer
+** {H12551} The second parameter to an
+**          [sqlite3_set_authorizer | authorizer callback] shall be an integer
 **          [SQLITE_COPY | authorizer code] that specifies what action
 **          is being authorized.
 **
-** {F12552} The 3rd and 4th parameters to the 
-**          [sqlite3_set_authorizer | authorization callback function]
-**          will be parameters or NULL depending on which 
+** {H12552} The 3rd and 4th parameters to the
+**          [sqlite3_set_authorizer | authorization callback]
+**          shall be parameters or NULL depending on which
 **          [SQLITE_COPY | authorizer code] is used as the second parameter.
 **
-** {F12553} The 5th parameter to the
-**          [sqlite3_set_authorizer | authorizer callback] is the name
+** {H12553} The 5th parameter to the
+**          [sqlite3_set_authorizer | authorizer callback] shall be the name
 **          of the database (example: "main", "temp", etc.) if applicable.
 **
-** {F12554} The 6th parameter to the
-**          [sqlite3_set_authorizer | authorizer callback] is the name
+** {H12554} The 6th parameter to the
+**          [sqlite3_set_authorizer | authorizer callback] shall be the name
 **          of the inner-most trigger or view that is responsible for
-**          the access attempt or NULL if this access attempt is directly from 
+**          the access attempt or NULL if this access attempt is directly from
 **          top-level SQL code.
 */
 /******************************************* 3rd ************ 4th ***********/
@@ -2252,7 +2836,8 @@ SQLITE_API int sqlite3_set_authorizer(
 #define SQLITE_COPY                  0   /* No longer used */
 
 /*
-** CAPI3REF: Tracing And Profiling Functions {F12280}
+** CAPI3REF: Tracing And Profiling Functions {H12280} 
+** EXPERIMENTAL
 **
 ** These routines register callback functions that can be used for
 ** tracing and profiling the execution of SQL statements.
@@ -2261,242 +2846,252 @@ SQLITE_API int sqlite3_set_authorizer(
 ** various times when an SQL statement is being run by [sqlite3_step()].
 ** The callback returns a UTF-8 rendering of the SQL statement text
 ** as the statement first begins executing.  Additional callbacks occur
-** as each triggersubprogram is entered.  The callbacks for triggers
+** as each triggered subprogram is entered.  The callbacks for triggers
 ** contain a UTF-8 SQL comment that identifies the trigger.
-** 
+**
 ** The callback function registered by sqlite3_profile() is invoked
 ** as each SQL statement finishes.  The profile callback contains
 ** the original statement text and an estimate of wall-clock time
 ** of how long that statement took to run.
 **
-** The sqlite3_profile() API is currently considered experimental and
-** is subject to change or removal in a future release.
-**
-** The trigger reporting feature of the trace callback is considered
-** experimental and is subject to change or removal in future releases.
-** Future versions of SQLite might also add new trace callback 
-** invocations.
-**
 ** INVARIANTS:
 **
-** {F12281} The callback function registered by [sqlite3_trace()] is
+** {H12281} The callback function registered by [sqlite3_trace()] 
+**          shall be invoked
 **          whenever an SQL statement first begins to execute and
 **          whenever a trigger subprogram first begins to run.
 **
-** {F12282} Each call to [sqlite3_trace()] overrides the previously
+** {H12282} Each call to [sqlite3_trace()] shall override the previously
 **          registered trace callback.
 **
-** {F12283} A NULL trace callback disables tracing.
+** {H12283} A NULL trace callback shall disable tracing.
 **
-** {F12284} The first argument to the trace callback is a copy of
+** {H12284} The first argument to the trace callback shall be a copy of
 **          the pointer which was the 3rd argument to [sqlite3_trace()].
 **
-** {F12285} The second argument to the trace callback is a
-**          zero-terminated UTF8 string containing the original text
+** {H12285} The second argument to the trace callback is a
+**          zero-terminated UTF-8 string containing the original text
 **          of the SQL statement as it was passed into [sqlite3_prepare_v2()]
 **          or the equivalent, or an SQL comment indicating the beginning
 **          of a trigger subprogram.
 **
-** {F12287} The callback function registered by [sqlite3_profile()] is invoked
+** {H12287} The callback function registered by [sqlite3_profile()] is invoked
 **          as each SQL statement finishes.
 **
-** {F12288} The first parameter to the profile callback is a copy of
+** {H12288} The first parameter to the profile callback is a copy of
 **          the 3rd parameter to [sqlite3_profile()].
 **
-** {F12289} The second parameter to the profile callback is a
+** {H12289} The second parameter to the profile callback is a
 **          zero-terminated UTF-8 string that contains the complete text of
 **          the SQL statement as it was processed by [sqlite3_prepare_v2()]
 **          or the equivalent.
 **
-** {F12290} The third parameter to the profile  callback is an estimate
+** {H12290} The third parameter to the profile callback is an estimate
 **          of the number of nanoseconds of wall-clock time required to
 **          run the SQL statement from start to finish.
 */
-SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
-SQLITE_API void *sqlite3_profile(sqlite3*,
+SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
+SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
    void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
 
 /*
-** CAPI3REF: Query Progress Callbacks {F12910}
+** CAPI3REF: Query Progress Callbacks {H12910} 
 **
 ** This routine configures a callback function - the
 ** progress callback - that is invoked periodically during long
 ** running calls to [sqlite3_exec()], [sqlite3_step()] and
-** [sqlite3_get_table()].   An example use for this 
+** [sqlite3_get_table()].  An example use for this
 ** interface is to keep a GUI updated during a large query.
 **
-** If the progress callback returns non-zero, the opertion is
+** If the progress callback returns non-zero, the operation is
 ** interrupted.  This feature can be used to implement a
-** "Cancel" button on a GUI dialog box.
+** "Cancel" button on a GUI progress dialog box.
+**
+** The progress handler must not do anything that will modify
+** the database connection that invoked the progress handler.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
 **
 ** INVARIANTS:
 **
-** {F12911} The callback function registered by [sqlite3_progress_handler()]
+** {H12911} The callback function registered by sqlite3_progress_handler()
 **          is invoked periodically during long running calls to
 **          [sqlite3_step()].
 **
-** {F12912} The progress callback is invoked once for every N virtual
-**          machine opcodes, where N is the second argument to 
+** {H12912} The progress callback is invoked once for every N virtual
+**          machine opcodes, where N is the second argument to
 **          the [sqlite3_progress_handler()] call that registered
-**          the callback.  What if N is less than 1?
+**          the callback.  If N is less than 1, sqlite3_progress_handler()
+**          acts as if a NULL progress handler had been specified.
 **
-** {F12913} The progress callback itself is identified by the third
-**          argument to [sqlite3_progress_handler()].
+** {H12913} The progress callback itself is identified by the third
+**          argument to sqlite3_progress_handler().
 **
-** {F12914} The fourth argument [sqlite3_progress_handler()] is a
-***         void pointer passed to the progress callback
+** {H12914} The fourth argument to sqlite3_progress_handler() is a
+**          void pointer passed to the progress callback
 **          function each time it is invoked.
 **
-** {F12915} If a call to [sqlite3_step()] results in fewer than
-**          N opcodes being executed,
-**          then the progress callback is never invoked. {END}
-** 
-** {F12916} Every call to [sqlite3_progress_handler()]
-**          overwrites any previously registere progress handler.
+** {H12915} If a call to [sqlite3_step()] results in fewer than N opcodes
+**          being executed, then the progress callback is never invoked.
+**
+** {H12916} Every call to [sqlite3_progress_handler()]
+**          overwrites any previously registered progress handler.
 **
-** {F12917} If the progress handler callback is NULL then no progress
+** {H12917} If the progress handler callback is NULL then no progress
 **          handler is invoked.
 **
-** {F12918} If the progress callback returns a result other than 0, then
+** {H12918} If the progress callback returns a result other than 0, then
 **          the behavior is a if [sqlite3_interrupt()] had been called.
+**          
 */
 SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
 
 /*
-** CAPI3REF: Opening A New Database Connection {F12700}
-**
-** These routines open an SQLite database file whose name
-** is given by the filename argument.
-** The filename argument is interpreted as UTF-8
-** for [sqlite3_open()] and [sqlite3_open_v2()] and as UTF-16
-** in the native byte order for [sqlite3_open16()].
-** An [sqlite3*] handle is usually returned in *ppDb, even
-** if an error occurs.  The only exception is if SQLite is unable
-** to allocate memory to hold the [sqlite3] object, a NULL will
-** be written into *ppDb instead of a pointer to the [sqlite3] object.
-** If the database is opened (and/or created)
-** successfully, then [SQLITE_OK] is returned.  Otherwise an
-** error code is returned.  The
-** [sqlite3_errmsg()] or [sqlite3_errmsg16()]  routines can be used to obtain
+** CAPI3REF: Opening A New Database Connection {H12700} 
+**
+** These routines open an SQLite database file whose name is given by the
+** filename argument. The filename argument is interpreted as UTF-8 for
+** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
+** order for sqlite3_open16(). A [database connection] handle is usually
+** returned in *ppDb, even if an error occurs.  The only exception is that
+** if SQLite is unable to allocate memory to hold the [sqlite3] object,
+** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
+** object. If the database is opened (and/or created) successfully, then
+** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.  The
+** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
 ** an English language description of the error.
 **
 ** The default encoding for the database will be UTF-8 if
-** [sqlite3_open()] or [sqlite3_open_v2()] is called and
-** UTF-16 in the native byte order if [sqlite3_open16()] is used.
+** sqlite3_open() or sqlite3_open_v2() is called and
+** UTF-16 in the native byte order if sqlite3_open16() is used.
 **
 ** Whether or not an error occurs when it is opened, resources
-** associated with the [sqlite3*] handle should be released by passing it
-** to [sqlite3_close()] when it is no longer required.
-**
-** The [sqlite3_open_v2()] interface works like [sqlite3_open()] 
-** except that it acccepts two additional parameters for additional control
-** over the new database connection.  The flags parameter can be
-** one of:
-**
-** 
    
-** 
  1.   [SQLITE_OPEN_READONLY]
-** 
  2.   [SQLITE_OPEN_READWRITE]
-** 
  3.   [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]
-** 

+** associated with the [database connection] handle should be released by
+** passing it to [sqlite3_close()] when it is no longer required.
+**
+** The sqlite3_open_v2() interface works like sqlite3_open()
+** except that it accepts two additional parameters for additional control
+** over the new database connection.  The flags parameter can take one of
+** the following three values, optionally combined with the 
+** [SQLITE_OPEN_NOMUTEX] or [SQLITE_OPEN_FULLMUTEX] flags:
+**
+** 

+** 
[SQLITE_OPEN_READONLY]

+** 
The database is opened in read-only mode.  If the database does not
+** already exist, an error is returned.

+**
+** 
[SQLITE_OPEN_READWRITE]

+** 
The database is opened for reading and writing if possible, or reading
+** only if the file is write protected by the operating system.  In either
+** case the database must already exist, otherwise an error is returned.

+**
+** 
[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]

+** 
The database is opened for reading and writing, and is creates it if
+** it does not already exist. This is the behavior that is always used for
+** sqlite3_open() and sqlite3_open16().

+** 

+**
+** If the 3rd parameter to sqlite3_open_v2() is not one of the
+** combinations shown above or one of the combinations shown above combined
+** with the [SQLITE_OPEN_NOMUTEX] or [SQLITE_OPEN_FULLMUTEX] flags,
+** then the behavior is undefined.
 **
-** The first value opens the database read-only. 
-** If the database does not previously exist, an error is returned.
-** The second option opens
-** the database for reading and writing if possible, or reading only if
-** if the file is write protected.  In either case the database
-** must already exist or an error is returned.  The third option
-** opens the database for reading and writing and creates it if it does
-** not already exist.
-** The third options is behavior that is always used for [sqlite3_open()]
-** and [sqlite3_open16()].
-**
-** If the filename is ":memory:", then an private
-** in-memory database is created for the connection.  This in-memory
-** database will vanish when the database connection is closed.  Future
-** version of SQLite might make use of additional special filenames
-** that begin with the ":" character.  It is recommended that 
-** when a database filename really does begin with
-** ":" that you prefix the filename with a pathname like "./" to
-** avoid ambiguity.
-**
-** If the filename is an empty string, then a private temporary
+** If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
+** opens in the multi-thread [threading mode] as long as the single-thread
+** mode has not been set at compile-time or start-time.  If the
+** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
+** in the serialized [threading mode] unless single-thread was
+** previously selected at compile-time or start-time.
+**
+** If the filename is ":memory:", then a private, temporary in-memory database
+** is created for the connection.  This in-memory database will vanish when
+** the database connection is closed.  Future versions of SQLite might
+** make use of additional special filenames that begin with the ":" character.
+** It is recommended that when a database filename actually does begin with
+** a ":" character you should prefix the filename with a pathname such as
+** "./" to avoid ambiguity.
+**
+** If the filename is an empty string, then a private, temporary
 ** on-disk database will be created.  This private database will be
 ** automatically deleted as soon as the database connection is closed.
 **
 ** The fourth parameter to sqlite3_open_v2() is the name of the
-** [sqlite3_vfs] object that defines the operating system 
-** interface that the new database connection should use.  If the
-** fourth parameter is a NULL pointer then the default [sqlite3_vfs]
-** object is used.
+** [sqlite3_vfs] object that defines the operating system interface that
+** the new database connection should use.  If the fourth parameter is
+** a NULL pointer then the default [sqlite3_vfs] object is used.
 **
-** Note to windows users:  The encoding used for the filename argument
-** of [sqlite3_open()] and [sqlite3_open_v2()] must be UTF-8, not whatever
+** Note to Windows users:  The encoding used for the filename argument
+** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
 ** codepage is currently defined.  Filenames containing international
 ** characters must be converted to UTF-8 prior to passing them into
-** [sqlite3_open()] or [sqlite3_open_v2()].
+** sqlite3_open() or sqlite3_open_v2().
 **
 ** INVARIANTS:
 **
-** {F12701} The [sqlite3_open()], [sqlite3_open16()], and
+** {H12701} The [sqlite3_open()], [sqlite3_open16()], and
 **          [sqlite3_open_v2()] interfaces create a new
 **          [database connection] associated with
 **          the database file given in their first parameter.
 **
-** {F12702} The filename argument is interpreted as UTF-8
+** {H12702} The filename argument is interpreted as UTF-8
 **          for [sqlite3_open()] and [sqlite3_open_v2()] and as UTF-16
 **          in the native byte order for [sqlite3_open16()].
 **
-** {F12703} A successful invocation of [sqlite3_open()], [sqlite3_open16()], 
+** {H12703} A successful invocation of [sqlite3_open()], [sqlite3_open16()],
 **          or [sqlite3_open_v2()] writes a pointer to a new
 **          [database connection] into *ppDb.
 **
-** {F12704} The [sqlite3_open()], [sqlite3_open16()], and
+** {H12704} The [sqlite3_open()], [sqlite3_open16()], and
 **          [sqlite3_open_v2()] interfaces return [SQLITE_OK] upon success,
 **          or an appropriate [error code] on failure.
 **
-** {F12706} The default text encoding for a new database created using
+** {H12706} The default text encoding for a new database created using
 **          [sqlite3_open()] or [sqlite3_open_v2()] will be UTF-8.
 **
-** {F12707} The default text encoding for a new database created using
+** {H12707} The default text encoding for a new database created using
 **          [sqlite3_open16()] will be UTF-16.
 **
-** {F12709} The [sqlite3_open(F,D)] interface is equivalent to
+** {H12709} The [sqlite3_open(F,D)] interface is equivalent to
 **          [sqlite3_open_v2(F,D,G,0)] where the G parameter is
 **          [SQLITE_OPEN_READWRITE]|[SQLITE_OPEN_CREATE].
 **
-** {F12711} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
+** {H12711} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
 **          bit value [SQLITE_OPEN_READONLY] then the database is opened
 **          for reading only.
 **
-** {F12712} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
+** {H12712} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
 **          bit value [SQLITE_OPEN_READWRITE] then the database is opened
 **          reading and writing if possible, or for reading only if the
 **          file is write protected by the operating system.
 **
-** {F12713} If the G parameter to [sqlite3_open(v2(F,D,G,V)] omits the
+** {H12713} If the G parameter to [sqlite3_open_v2(F,D,G,V)] omits the
 **          bit value [SQLITE_OPEN_CREATE] and the database does not
 **          previously exist, an error is returned.
 **
-** {F12714} If the G parameter to [sqlite3_open(v2(F,D,G,V)] contains the
+** {H12714} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
 **          bit value [SQLITE_OPEN_CREATE] and the database does not
 **          previously exist, then an attempt is made to create and
 **          initialize the database.
 **
-** {F12717} If the filename argument to [sqlite3_open()], [sqlite3_open16()],
+** {H12717} If the filename argument to [sqlite3_open()], [sqlite3_open16()],
 **          or [sqlite3_open_v2()] is ":memory:", then an private,
 **          ephemeral, in-memory database is created for the connection.
 **          Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required
 **          in sqlite3_open_v2()?
 **
-** {F12719} If the filename is NULL or an empty string, then a private,
-**          ephermeral on-disk database will be created.
+** {H12719} If the filename is NULL or an empty string, then a private,
+**          ephemeral on-disk database will be created.
 **          Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required
 **          in sqlite3_open_v2()?
 **
-** {F12721} The [database connection] created by 
-**          [sqlite3_open_v2(F,D,G,V)] will use the
-**          [sqlite3_vfs] object identified by the V parameter, or
-**          the default [sqlite3_vfs] object is V is a NULL pointer.
+** {H12721} The [database connection] created by [sqlite3_open_v2(F,D,G,V)]
+**          will use the [sqlite3_vfs] object identified by the V parameter,
+**          or the default [sqlite3_vfs] object if V is a NULL pointer.
+**
+** {H12723} Two [database connections] will share a common cache if both were
+**          opened with the same VFS while [shared cache mode] was enabled and
+**          if both filenames compare equal using memcmp() after having been
+**          processed by the [sqlite3_vfs | xFullPathname] method of the VFS.
 */
 SQLITE_API int sqlite3_open(
   const char *filename,   /* Database filename (UTF-8) */
@@ -2514,44 +3109,45 @@ SQLITE_API int sqlite3_open_v2(
 );
 
 /*
-** CAPI3REF: Error Codes And Messages {F12800}
+** CAPI3REF: Error Codes And Messages {H12800} 
 **
-** The sqlite3_errcode() interface returns the numeric
-** [SQLITE_OK | result code] or [SQLITE_IOERR_READ | extended result code]
-** for the most recent failed sqlite3_* API call associated
-** with [sqlite3] handle 'db'. If a prior API call failed but the
-** most recent API call succeeded, the return value from sqlite3_errcode()
-** is undefined.
+** The sqlite3_errcode() interface returns the numeric [result code] or
+** [extended result code] for the most recent failed sqlite3_* API call
+** associated with a [database connection]. If a prior API call failed
+** but the most recent API call succeeded, the return value from
+** sqlite3_errcode() is undefined.
 **
 ** The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
-** text that describes the error, as either UTF8 or UTF16 respectively.
+** text that describes the error, as either UTF-8 or UTF-16 respectively.
 ** Memory to hold the error message string is managed internally.
-** The application does not need to worry with freeing the result.
+** The application does not need to worry about freeing the result.
 ** However, the error string might be overwritten or deallocated by
 ** subsequent calls to other SQLite interface functions.
 **
+** If an interface fails with SQLITE_MISUSE, that means the interface
+** was invoked incorrectly by the application.  In that case, the
+** error code and message may or may not be set.
+**
 ** INVARIANTS:
 **
-** {F12801} The [sqlite3_errcode(D)] interface returns the numeric
-**          [SQLITE_OK | result code] or
-**          [SQLITE_IOERR_READ | extended result code]
-**          for the most recently failed interface call associated
-**          with [database connection] D.
+** {H12801} The [sqlite3_errcode(D)] interface returns the numeric
+**          [result code] or [extended result code] for the most recently
+**          failed interface call associated with the [database connection] D.
 **
-** {F12803} The [sqlite3_errmsg(D)] and [sqlite3_errmsg16(D)]
+** {H12803} The [sqlite3_errmsg(D)] and [sqlite3_errmsg16(D)]
 **          interfaces return English-language text that describes
 **          the error in the mostly recently failed interface call,
-**          encoded as either UTF8 or UTF16 respectively.
+**          encoded as either UTF-8 or UTF-16 respectively.
 **
-** {F12807} The strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()]
+** {H12807} The strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()]
 **          are valid until the next SQLite interface call.
 **
-** {F12808} Calls to API routines that do not return an error code
+** {H12808} Calls to API routines that do not return an error code
 **          (example: [sqlite3_data_count()]) do not
 **          change the error code or message returned by
 **          [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()].
 **
-** {F12809} Interfaces that are not associated with a specific
+** {H12809} Interfaces that are not associated with a specific
 **          [database connection] (examples:
 **          [sqlite3_mprintf()] or [sqlite3_enable_shared_cache()]
 **          do not change the values returned by
@@ -2562,20 +3158,20 @@ SQLITE_API const char *sqlite3_errmsg(sqlite3*);
 SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
 
 /*
-** CAPI3REF: SQL Statement Object {F13000}
+** CAPI3REF: SQL Statement Object {H13000} 
 ** KEYWORDS: {prepared statement} {prepared statements}
 **
-** An instance of this object represent single SQL statements.  This
-** object is variously known as a "prepared statement" or a 
+** An instance of this object represents a single SQL statement.
+** This object is variously known as a "prepared statement" or a
 ** "compiled SQL statement" or simply as a "statement".
-** 
+**
 ** The life of a statement object goes something like this:
 **
 ** 
    
 ** 
  1.  Create the object using [sqlite3_prepare_v2()] or a related
 **      function.
-** 
  2.  Bind values to host parameters using
-**      [sqlite3_bind_blob | sqlite3_bind_* interfaces].
+** 
  3.  Bind values to [host parameters] using the sqlite3_bind_*()
+**      interfaces.
 ** 
  4.  Run the SQL by calling [sqlite3_step()] one or more times.
 ** 
  5.  Reset the statement using [sqlite3_reset()] then go back
 **      to step 2.  Do this zero or more times.
@@ -2588,48 +3184,154 @@ SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
 typedef struct sqlite3_stmt sqlite3_stmt;
 
 /*
-** CAPI3REF: Compiling An SQL Statement {F13010}
+** CAPI3REF: Run-time Limits {H12760} 
+**
+** This interface allows the size of various constructs to be limited
+** on a connection by connection basis.  The first parameter is the
+** [database connection] whose limit is to be set or queried.  The
+** second parameter is one of the [limit categories] that define a
+** class of constructs to be size limited.  The third parameter is the
+** new limit for that construct.  The function returns the old limit.
+**
+** If the new limit is a negative number, the limit is unchanged.
+** For the limit category of SQLITE_LIMIT_XYZ there is a hard upper
+** bound set by a compile-time C preprocessor macro named SQLITE_MAX_XYZ.
+** (The "_LIMIT_" in the name is changed to "_MAX_".)
+** Attempts to increase a limit above its hard upper bound are
+** silently truncated to the hard upper limit.
+**
+** Run time limits are intended for use in applications that manage
+** both their own internal database and also databases that are controlled
+** by untrusted external sources.  An example application might be a
+** webbrowser that has its own databases for storing history and
+** separate databases controlled by JavaScript applications downloaded
+** off the Internet.  The internal databases can be given the
+** large, default limits.  Databases managed by external sources can
+** be given much smaller limits designed to prevent a denial of service
+** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
+** interface to further control untrusted SQL.  The size of the database
+** created by an untrusted script can be contained using the
+** [max_page_count] [PRAGMA].
+**
+** New run-time limit categories may be added in future releases.
+**
+** INVARIANTS:
+**
+** {H12762} A successful call to [sqlite3_limit(D,C,V)] where V is
+**          positive changes the limit on the size of construct C in the
+**          [database connection] D to the lesser of V and the hard upper
+**          bound on the size of C that is set at compile-time.
+**
+** {H12766} A successful call to [sqlite3_limit(D,C,V)] where V is negative
+**          leaves the state of the [database connection] D unchanged.
+**
+** {H12769} A successful call to [sqlite3_limit(D,C,V)] returns the
+**          value of the limit on the size of construct C in the
+**          [database connection] D as it was prior to the call.
+*/
+SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
+
+/*
+** CAPI3REF: Run-Time Limit Categories {H12790} 
+** KEYWORDS: {limit category} {limit categories}
+**
+** These constants define various aspects of a [database connection]
+** that can be limited in size by calls to [sqlite3_limit()].
+** The meanings of the various limits are as follows:
+**
+** 
    
+** 
    SQLITE_LIMIT_LENGTH
    
+** 
    The maximum size of any string or BLOB or table row.
    
+**
+** 
    SQLITE_LIMIT_SQL_LENGTH
    
+** 
    The maximum length of an SQL statement.
    
+**
+** 
    SQLITE_LIMIT_COLUMN
    
+** 
    The maximum number of columns in a table definition or in the
+** result set of a SELECT or the maximum number of columns in an index
+** or in an ORDER BY or GROUP BY clause.
    
+**
+** 
    SQLITE_LIMIT_EXPR_DEPTH
    
+** 
    The maximum depth of the parse tree on any expression.
    
+**
+** 
    SQLITE_LIMIT_COMPOUND_SELECT
    
+** 
    The maximum number of terms in a compound SELECT statement.
    
+**
+** 
    SQLITE_LIMIT_VDBE_OP
    
+** 
    The maximum number of instructions in a virtual machine program
+** used to implement an SQL statement.
    
+**
+** 
    SQLITE_LIMIT_FUNCTION_ARG
    
+** 
    The maximum number of arguments on a function.
    
+**
+** 
    SQLITE_LIMIT_ATTACHED
    
+** 
    The maximum number of attached databases.
    
+**
+** 
    SQLITE_LIMIT_LIKE_PATTERN_LENGTH
    
+** 
    The maximum length of the pattern argument to the LIKE or
+** GLOB operators.
    
+**
+** 
    SQLITE_LIMIT_VARIABLE_NUMBER
    
+** 
    The maximum number of variables in an SQL statement that can
+** be bound.
    
+** 
    
+*/
+#define SQLITE_LIMIT_LENGTH                    0
+#define SQLITE_LIMIT_SQL_LENGTH                1
+#define SQLITE_LIMIT_COLUMN                    2
+#define SQLITE_LIMIT_EXPR_DEPTH                3
+#define SQLITE_LIMIT_COMPOUND_SELECT           4
+#define SQLITE_LIMIT_VDBE_OP                   5
+#define SQLITE_LIMIT_FUNCTION_ARG              6
+#define SQLITE_LIMIT_ATTACHED                  7
+#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
+#define SQLITE_LIMIT_VARIABLE_NUMBER           9
+
+/*
+** CAPI3REF: Compiling An SQL Statement {H13010} 
+** KEYWORDS: {SQL statement compiler}
 **
 ** To execute an SQL query, it must first be compiled into a byte-code
-** program using one of these routines. 
+** program using one of these routines.
 **
-** The first argument "db" is an [database connection] 
-** obtained from a prior call to [sqlite3_open()], [sqlite3_open_v2()]
-** or [sqlite3_open16()]. 
-** The second argument "zSql" is the statement to be compiled, encoded
-** as either UTF-8 or UTF-16.  The sqlite3_prepare() and sqlite3_prepare_v2()
-** interfaces uses UTF-8 and sqlite3_prepare16() and sqlite3_prepare16_v2()
-** use UTF-16. {END}
+** The first argument, "db", is a [database connection] obtained from a
+** prior call to [sqlite3_open()], [sqlite3_open_v2()] or [sqlite3_open16()].
 **
-** If the nByte argument is less
-** than zero, then zSql is read up to the first zero terminator.
-** If nByte is non-negative, then it is the maximum number of 
-** bytes read from zSql.  When nByte is non-negative, the
-** zSql string ends at either the first '\000' or '\u0000' character or 
-** until the nByte-th byte, whichever comes first. {END}
+** The second argument, "zSql", is the statement to be compiled, encoded
+** as either UTF-8 or UTF-16.  The sqlite3_prepare() and sqlite3_prepare_v2()
+** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
+** use UTF-16.
+**
+** If the nByte argument is less than zero, then zSql is read up to the
+** first zero terminator. If nByte is non-negative, then it is the maximum
+** number of  bytes read from zSql.  When nByte is non-negative, the
+** zSql string ends at either the first '\000' or '\u0000' character or
+** the nByte-th byte, whichever comes first. If the caller knows
+** that the supplied string is nul-terminated, then there is a small
+** performance advantage to be gained by passing an nByte parameter that
+** is equal to the number of bytes in the input string including
+** the nul-terminator bytes.
 **
 ** *pzTail is made to point to the first byte past the end of the
-** first SQL statement in zSql.  These routines only compiles the first
+** first SQL statement in zSql.  These routines only compile the first
 ** statement in zSql, so *pzTail is left pointing to what remains
 ** uncompiled.
 **
 ** *ppStmt is left pointing to a compiled [prepared statement] that can be
-** executed using [sqlite3_step()].  Or if there is an error, *ppStmt is
-** set to NULL.  If the input text contains no SQL (if the input
-** is and empty string or a comment) then *ppStmt is set to NULL.
-** {U13018} The calling procedure is responsible for deleting the
-** compiled SQL statement
-** using [sqlite3_finalize()] after it has finished with it.
+** executed using [sqlite3_step()].  If there is an error, *ppStmt is set
+** to NULL.  If the input text contains no SQL (if the input is an empty
+** string or a comment) then *ppStmt is set to NULL.
+** {A13018} The calling procedure is responsible for deleting the compiled
+** SQL statement using [sqlite3_finalize()] after it has finished with it.
 **
-** On success, [SQLITE_OK] is returned.  Otherwise an 
-** [error code] is returned.
+** On success, [SQLITE_OK] is returned, otherwise an [error code] is returned.
 **
 ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
 ** recommended for all new programs. The two older interfaces are retained
 ** for backwards compatibility, but their use is discouraged.
 ** In the "v2" interfaces, the prepared statement
-** that is returned (the [sqlite3_stmt] object) contains a copy of the 
-** original SQL text. {END} This causes the [sqlite3_step()] interface to
+** that is returned (the [sqlite3_stmt] object) contains a copy of the
+** original SQL text. This causes the [sqlite3_step()] interface to
 ** behave a differently in two ways:
 **
 ** 
      
@@ -2638,60 +3340,57 @@ typedef struct sqlite3_stmt sqlite3_stmt;
 ** always used to do, [sqlite3_step()] will automatically recompile the SQL
 ** statement and try to run it again.  If the schema has changed in
 ** a way that makes the statement no longer valid, [sqlite3_step()] will still
-** return [SQLITE_SCHEMA].  But unlike the legacy behavior, 
-** [SQLITE_SCHEMA] is now a fatal error.  Calling
-** [sqlite3_prepare_v2()] again will not make the
+** return [SQLITE_SCHEMA].  But unlike the legacy behavior, [SQLITE_SCHEMA] is
+** now a fatal error.  Calling [sqlite3_prepare_v2()] again will not make the
 ** error go away.  Note: use [sqlite3_errmsg()] to find the text
-** of the parsing error that results in an [SQLITE_SCHEMA] return. {END}
+** of the parsing error that results in an [SQLITE_SCHEMA] return.
 ** 
 **
 ** 
    1. 
-** When an error occurs, 
-** [sqlite3_step()] will return one of the detailed 
-** [error codes] or [extended error codes]. 
-** The legacy behavior was that [sqlite3_step()] would only return a generic
-** [SQLITE_ERROR] result code and you would have to make a second call to
-** [sqlite3_reset()] in order to find the underlying cause of the problem.
-** With the "v2" prepare interfaces, the underlying reason for the error is
-** returned immediately.
+** When an error occurs, [sqlite3_step()] will return one of the detailed
+** [error codes] or [extended error codes].  The legacy behavior was that
+** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
+** and you would have to make a second call to [sqlite3_reset()] in order
+** to find the underlying cause of the problem. With the "v2" prepare
+** interfaces, the underlying reason for the error is returned immediately.
 ** 
      2. 
 ** 
    
 **
 ** INVARIANTS:
 **
-** {F13011} The [sqlite3_prepare(db,zSql,...)] and
+** {H13011} The [sqlite3_prepare(db,zSql,...)] and
 **          [sqlite3_prepare_v2(db,zSql,...)] interfaces interpret the
 **          text in their zSql parameter as UTF-8.
 **
-** {F13012} The [sqlite3_prepare16(db,zSql,...)] and
+** {H13012} The [sqlite3_prepare16(db,zSql,...)] and
 **          [sqlite3_prepare16_v2(db,zSql,...)] interfaces interpret the
 **          text in their zSql parameter as UTF-16 in the native byte order.
 **
-** {F13013} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
-**          and its variants is less than zero, then SQL text is
+** {H13013} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
+**          and its variants is less than zero, the SQL text is
 **          read from zSql is read up to the first zero terminator.
 **
-** {F13014} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
-**          and its variants is non-negative, then nBytes bytes
+** {H13014} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
+**          and its variants is non-negative, then at most nBytes bytes of
 **          SQL text is read from zSql.
 **
-** {F13015} In [sqlite3_prepare_v2(db,zSql,N,P,pzTail)] and its variants
+** {H13015} In [sqlite3_prepare_v2(db,zSql,N,P,pzTail)] and its variants
 **          if the zSql input text contains more than one SQL statement
 **          and pzTail is not NULL, then *pzTail is made to point to the
 **          first byte past the end of the first SQL statement in zSql.
 **          What does *pzTail point to if there is one statement?
 **
-** {F13016} A successful call to [sqlite3_prepare_v2(db,zSql,N,ppStmt,...)]
+** {H13016} A successful call to [sqlite3_prepare_v2(db,zSql,N,ppStmt,...)]
 **          or one of its variants writes into *ppStmt a pointer to a new
-**          [prepared statement] or a pointer to NULL
-**          if zSql contains nothing other than whitespace or comments. 
+**          [prepared statement] or a pointer to NULL if zSql contains
+**          nothing other than whitespace or comments.
 **
-** {F13019} The [sqlite3_prepare_v2()] interface and its variants return
+** {H13019} The [sqlite3_prepare_v2()] interface and its variants return
 **          [SQLITE_OK] or an appropriate [error code] upon failure.
 **
-** {F13021} Before [sqlite3_prepare(db,zSql,nByte,ppStmt,pzTail)] or its
-**          variants returns an error (any value other than [SQLITE_OK])
-**          it first sets *ppStmt to NULL.
+** {H13021} Before [sqlite3_prepare(db,zSql,nByte,ppStmt,pzTail)] or its
+**          variants returns an error (any value other than [SQLITE_OK]),
+**          they first set *ppStmt to NULL.
 */
 SQLITE_API int sqlite3_prepare(
   sqlite3 *db,            /* Database handle */
@@ -2723,58 +3422,89 @@ SQLITE_API int sqlite3_prepare16_v2(
 );
 
 /*
-** CAPIREF: Retrieving Statement SQL {F13100}
+** CAPI3REF: Retrieving Statement SQL {H13100} 
 **
-** This intereface can be used to retrieve a saved copy of the original
-** SQL text used to create a [prepared statement].
+** This interface can be used to retrieve a saved copy of the original
+** SQL text used to create a [prepared statement] if that statement was
+** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
 **
 ** INVARIANTS:
 **
-** {F13101} If the [prepared statement] passed as 
-**          the an argument to [sqlite3_sql()] was compiled
-**          compiled using either [sqlite3_prepare_v2()] or
-**          [sqlite3_prepare16_v2()],
-**          then [sqlite3_sql()] function returns a pointer to a
-**          zero-terminated string containing a UTF-8 rendering
+** {H13101} If the [prepared statement] passed as the argument to
+**          [sqlite3_sql()] was compiled using either [sqlite3_prepare_v2()] or
+**          [sqlite3_prepare16_v2()], then [sqlite3_sql()] returns
+**          a pointer to a zero-terminated string containing a UTF-8 rendering
 **          of the original SQL statement.
 **
-** {F13102} If the [prepared statement] passed as 
-**          the an argument to [sqlite3_sql()] was compiled
-**          compiled using either [sqlite3_prepare()] or
-**          [sqlite3_prepare16()],
-**          then [sqlite3_sql()] function returns a NULL pointer.
+** {H13102} If the [prepared statement] passed as the argument to
+**          [sqlite3_sql()] was compiled using either [sqlite3_prepare()] or
+**          [sqlite3_prepare16()], then [sqlite3_sql()] returns a NULL pointer.
 **
-** {F13103} The string returned by [sqlite3_sql(S)] is valid until the
+** {H13103} The string returned by [sqlite3_sql(S)] is valid until the
 **          [prepared statement] S is deleted using [sqlite3_finalize(S)].
 */
 SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF:  Dynamically Typed Value Object  {F15000}
+** CAPI3REF: Dynamically Typed Value Object {H15000} 
+** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
 **
 ** SQLite uses the sqlite3_value object to represent all values
-** that are or can be stored in a database table.
-** SQLite uses dynamic typing for the values it stores.  
-** Values stored in sqlite3_value objects can be
-** be integers, floating point values, strings, BLOBs, or NULL.
+** that can be stored in a database table. SQLite uses dynamic typing
+** for the values it stores. Values stored in sqlite3_value objects
+** can be integers, floating point values, strings, BLOBs, or NULL.
+**
+** An sqlite3_value object may be either "protected" or "unprotected".
+** Some interfaces require a protected sqlite3_value.  Other interfaces
+** will accept either a protected or an unprotected sqlite3_value.
+** Every interface that accepts sqlite3_value arguments specifies
+** whether or not it requires a protected sqlite3_value.
+**
+** The terms "protected" and "unprotected" refer to whether or not
+** a mutex is held.  A internal mutex is held for a protected
+** sqlite3_value object but no mutex is held for an unprotected
+** sqlite3_value object.  If SQLite is compiled to be single-threaded
+** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
+** or if SQLite is run in one of reduced mutex modes 
+** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
+** then there is no distinction between protected and unprotected
+** sqlite3_value objects and they can be used interchangeably.  However,
+** for maximum code portability it is recommended that applications
+** still make the distinction between between protected and unprotected
+** sqlite3_value objects even when not strictly required.
+**
+** The sqlite3_value objects that are passed as parameters into the
+** implementation of [application-defined SQL functions] are protected.
+** The sqlite3_value object returned by
+** [sqlite3_column_value()] is unprotected.
+** Unprotected sqlite3_value objects may only be used with
+** [sqlite3_result_value()] and [sqlite3_bind_value()].
+** The [sqlite3_value_blob | sqlite3_value_type()] family of
+** interfaces require protected sqlite3_value objects.
 */
 typedef struct Mem sqlite3_value;
 
 /*
-** CAPI3REF:  SQL Function Context Object {F16001}
+** CAPI3REF: SQL Function Context Object {H16001} 
 **
 ** The context in which an SQL function executes is stored in an
-** sqlite3_context object.  A pointer to an sqlite3_context
-** object is always first parameter to application-defined SQL functions.
+** sqlite3_context object.  A pointer to an sqlite3_context object
+** is always first parameter to [application-defined SQL functions].
+** The application-defined SQL function implementation will pass this
+** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
+** [sqlite3_aggregate_context()], [sqlite3_user_data()],
+** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
+** and/or [sqlite3_set_auxdata()].
 */
 typedef struct sqlite3_context sqlite3_context;
 
 /*
-** CAPI3REF:  Binding Values To Prepared Statements {F13500}
+** CAPI3REF: Binding Values To Prepared Statements {H13500} 
+** KEYWORDS: {host parameter} {host parameters} {host parameter name}
+** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
 **
-** In the SQL strings input to [sqlite3_prepare_v2()] and its
-** variants, literals may be replace by a parameter in one
-** of these forms:
+** In the SQL strings input to [sqlite3_prepare_v2()] and its variants,
+** literals may be replaced by a parameter in one of these forms:
 **
 ** 
      
 ** 
    •   ?
@@ -2785,33 +3515,31 @@ typedef struct sqlite3_context sqlite3_context;
 ** 
    
 **
 ** In the parameter forms shown above NNN is an integer literal,
-** VVV alpha-numeric parameter name.
-** The values of these parameters (also called "host parameter names"
-** or "SQL parameters")
+** and VVV is an alpha-numeric parameter name. The values of these
+** parameters (also called "host parameter names" or "SQL parameters")
 ** can be set using the sqlite3_bind_*() routines defined here.
 **
-** The first argument to the sqlite3_bind_*() routines always
-** is a pointer to the [sqlite3_stmt] object returned from
-** [sqlite3_prepare_v2()] or its variants. The second
-** argument is the index of the parameter to be set. The
-** first parameter has an index of 1.  When the same named
-** parameter is used more than once, second and subsequent
-** occurrences have the same index as the first occurrence. 
+** The first argument to the sqlite3_bind_*() routines is always
+** a pointer to the [sqlite3_stmt] object returned from
+** [sqlite3_prepare_v2()] or its variants.
+**
+** The second argument is the index of the SQL parameter to be set.
+** The leftmost SQL parameter has an index of 1.  When the same named
+** SQL parameter is used more than once, second and subsequent
+** occurrences have the same index as the first occurrence.
 ** The index for named parameters can be looked up using the
-** [sqlite3_bind_parameter_name()] API if desired.  The index
+** [sqlite3_bind_parameter_index()] API if desired.  The index
 ** for "?NNN" parameters is the value of NNN.
-** The NNN value must be between 1 and the compile-time
-** parameter SQLITE_MAX_VARIABLE_NUMBER (default value: 999).
+** The NNN value must be between 1 and the [sqlite3_limit()]
+** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
 **
 ** The third argument is the value to bind to the parameter.
 **
-** In those
-** routines that have a fourth argument, its value is the number of bytes
-** in the parameter.  To be clear: the value is the number of bytes
-** in the value, not the number of characters.   The number
-** of bytes does not include the zero-terminator at the end of strings.
+** In those routines that have a fourth argument, its value is the
+** number of bytes in the parameter.  To be clear: the value is the
+** number of bytes in the value, not the number of characters.
 ** If the fourth parameter is negative, the length of the string is
-** number of bytes up to the first zero terminator.
+** the number of bytes up to the first zero terminator.
 **
 ** The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
 ** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
@@ -2823,12 +3551,12 @@ typedef struct sqlite3_context sqlite3_context;
 ** the sqlite3_bind_*() routine returns.
 **
 ** The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
-** is filled with zeros.  A zeroblob uses a fixed amount of memory
-** (just an integer to hold it size) while it is being processed.
-** Zeroblobs are intended to serve as place-holders for BLOBs whose
-** content is later written using 
-** [sqlite3_blob_open | increment BLOB I/O] routines. A negative
-** value for the zeroblob results in a zero-length BLOB.
+** is filled with zeroes.  A zeroblob uses a fixed amount of memory
+** (just an integer to hold its size) while it is being processed.
+** Zeroblobs are intended to serve as placeholders for BLOBs whose
+** content is later written using
+** [sqlite3_blob_open | incremental BLOB I/O] routines.
+** A negative value for the zeroblob results in a zero-length BLOB.
 **
 ** The sqlite3_bind_*() routines must be called after
 ** [sqlite3_prepare_v2()] (and its variants) or [sqlite3_reset()] and
@@ -2838,7 +3566,7 @@ typedef struct sqlite3_context sqlite3_context;
 **
 ** These routines return [SQLITE_OK] on success or an error code if
 ** anything goes wrong.  [SQLITE_RANGE] is returned if the parameter
-** index is out of range.  [SQLITE_NOMEM] is returned if malloc fails.
+** index is out of range.  [SQLITE_NOMEM] is returned if malloc() fails.
 ** [SQLITE_MISUSE] might be returned if these routines are called on a
 ** virtual machine that is the wrong state or which has already been finalized.
 ** Detection of misuse is unreliable.  Applications should not depend
@@ -2847,77 +3575,81 @@ typedef struct sqlite3_context sqlite3_context;
 ** panic rather than return SQLITE_MISUSE.
 **
 ** See also: [sqlite3_bind_parameter_count()],
-** [sqlite3_bind_parameter_name()], and
-** [sqlite3_bind_parameter_index()].
+** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
 **
 ** INVARIANTS:
 **
-** {F13506} The [sqlite3_prepare | SQL statement compiler] recognizes
-**          tokens of the forms "?", "?NNN", "$VVV", ":VVV", and "@VVV"
-**          as SQL parameters, where NNN is any sequence of one or more
-**          digits and where VVV is any sequence of one or more 
-**          alphanumeric characters or "::" optionally followed by
-**          a string containing no spaces and contained within parentheses.
+** {H13506} The [SQL statement compiler] recognizes tokens of the forms
+**          "?", "?NNN", "$VVV", ":VVV", and "@VVV" as SQL parameters,
+**          where NNN is any sequence of one or more digits
+**          and where VVV is any sequence of one or more alphanumeric
+**          characters or "::" optionally followed by a string containing
+**          no spaces and contained within parentheses.
 **
-** {F13509} The initial value of an SQL parameter is NULL.
+** {H13509} The initial value of an SQL parameter is NULL.
 **
-** {F13512} The index of an "?" SQL parameter is one larger than the
+** {H13512} The index of an "?" SQL parameter is one larger than the
 **          largest index of SQL parameter to the left, or 1 if
 **          the "?" is the leftmost SQL parameter.
 **
-** {F13515} The index of an "?NNN" SQL parameter is the integer NNN.
+** {H13515} The index of an "?NNN" SQL parameter is the integer NNN.
 **
-** {F13518} The index of an ":VVV", "$VVV", or "@VVV" SQL parameter is
-**          the same as the index of leftmost occurances of the same
+** {H13518} The index of an ":VVV", "$VVV", or "@VVV" SQL parameter is
+**          the same as the index of leftmost occurrences of the same
 **          parameter, or one more than the largest index over all
-**          parameters to the left if this is the first occurrance
+**          parameters to the left if this is the first occurrence
 **          of this parameter, or 1 if this is the leftmost parameter.
 **
-** {F13521} The [sqlite3_prepare | SQL statement compiler] fail with
-**          an [SQLITE_RANGE] error if the index of an SQL parameter
-**          is less than 1 or greater than SQLITE_MAX_VARIABLE_NUMBER.
+** {H13521} The [SQL statement compiler] fails with an [SQLITE_RANGE]
+**          error if the index of an SQL parameter is less than 1
+**          or greater than the compile-time SQLITE_MAX_VARIABLE_NUMBER
+**          parameter.
 **
-** {F13524} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,V,...)]
+** {H13524} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,V,...)]
 **          associate the value V with all SQL parameters having an
 **          index of N in the [prepared statement] S.
 **
-** {F13527} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,...)]
+** {H13527} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,...)]
 **          override prior calls with the same values of S and N.
 **
-** {F13530} Bindings established by [sqlite3_bind_text | sqlite3_bind(S,...)]
+** {H13530} Bindings established by [sqlite3_bind_text | sqlite3_bind(S,...)]
 **          persist across calls to [sqlite3_reset(S)].
 **
-** {F13533} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
+** {H13533} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
 **          [sqlite3_bind_text(S,N,V,L,D)], or
 **          [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds the first L
-**          bytes of the blob or string pointed to by V, when L
+**          bytes of the BLOB or string pointed to by V, when L
 **          is non-negative.
 **
-** {F13536} In calls to [sqlite3_bind_text(S,N,V,L,D)] or
+** {H13536} In calls to [sqlite3_bind_text(S,N,V,L,D)] or
 **          [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds characters
 **          from V through the first zero character when L is negative.
 **
-** {F13539} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
+** {H13539} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
 **          [sqlite3_bind_text(S,N,V,L,D)], or
 **          [sqlite3_bind_text16(S,N,V,L,D)] when D is the special
 **          constant [SQLITE_STATIC], SQLite assumes that the value V
 **          is held in static unmanaged space that will not change
 **          during the lifetime of the binding.
 **
-** {F13542} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
+** {H13542} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
 **          [sqlite3_bind_text(S,N,V,L,D)], or
 **          [sqlite3_bind_text16(S,N,V,L,D)] when D is the special
-**          constant [SQLITE_TRANSIENT], the routine makes a 
-**          private copy of V value before it returns.
+**          constant [SQLITE_TRANSIENT], the routine makes a
+**          private copy of the value V before it returns.
 **
-** {F13545} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
+** {H13545} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
 **          [sqlite3_bind_text(S,N,V,L,D)], or
 **          [sqlite3_bind_text16(S,N,V,L,D)] when D is a pointer to
 **          a function, SQLite invokes that function to destroy the
-**          V value after it has finished using the V value.
+**          value V after it has finished using the value V.
 **
-** {F13548} In calls to [sqlite3_bind_zeroblob(S,N,V,L)] the value bound
-**          is a blob of L bytes, or a zero-length blob if L is negative.
+** {H13548} In calls to [sqlite3_bind_zeroblob(S,N,V,L)] the value bound
+**          is a BLOB of L bytes, or a zero-length BLOB if L is negative.
+**
+** {H13551} In calls to [sqlite3_bind_value(S,N,V)] the V argument may
+**          be either a [protected sqlite3_value] object or an
+**          [unprotected sqlite3_value] object.
 */
 SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
 SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
@@ -2930,18 +3662,18 @@ SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
 SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
 
 /*
-** CAPI3REF: Number Of SQL Parameters {F13600}
+** CAPI3REF: Number Of SQL Parameters {H13600} 
 **
-** This routine can be used to find the number of SQL parameters
-** in a prepared statement.  SQL parameters are tokens of the
+** This routine can be used to find the number of [SQL parameters]
+** in a [prepared statement].  SQL parameters are tokens of the
 ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
-** place-holders for values that are [sqlite3_bind_blob | bound]
+** placeholders for values that are [sqlite3_bind_blob | bound]
 ** to the parameters at a later time.
 **
-** This routine actually returns the index of the largest parameter.
-** For all forms except ?NNN, this will correspond to the number of
-** unique parameters.  If parameters of the ?NNN are used, there may
-** be gaps in the list.
+** This routine actually returns the index of the largest (rightmost)
+** parameter. For all forms except ?NNN, this will correspond to the
+** number of unique parameters.  If parameters of the ?NNN are used,
+** there may be gaps in the list.
 **
 ** See also: [sqlite3_bind_blob|sqlite3_bind()],
 ** [sqlite3_bind_parameter_name()], and
@@ -2949,29 +3681,30 @@ SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
 **
 ** INVARIANTS:
 **
-** {F13601} The [sqlite3_bind_parameter_count(S)] interface returns
+** {H13601} The [sqlite3_bind_parameter_count(S)] interface returns
 **          the largest index of all SQL parameters in the
-**          [prepared statement] S, or 0 if S
-**          contains no SQL parameters.
+**          [prepared statement] S, or 0 if S contains no SQL parameters.
 */
 SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
 
 /*
-** CAPI3REF: Name Of A Host Parameter {F13620}
+** CAPI3REF: Name Of A Host Parameter {H13620} 
 **
 ** This routine returns a pointer to the name of the n-th
-** SQL parameter in a [prepared statement].
-** SQL parameters of the form ":AAA" or "@AAA" or "$AAA" have a name
-** which is the string ":AAA" or "@AAA" or "$VVV". 
-** In other words, the initial ":" or "$" or "@"
+** [SQL parameter] in a [prepared statement].
+** SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
+** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
+** respectively.
+** In other words, the initial ":" or "$" or "@" or "?"
 ** is included as part of the name.
-** Parameters of the form "?" or "?NNN" have no name.
+** Parameters of the form "?" without a following integer have no name
+** and are also referred to as "anonymous parameters".
 **
 ** The first host parameter has an index of 1, not 0.
 **
 ** If the value n is out of range or if the n-th parameter is
 ** nameless, then NULL is returned.  The returned string is
-** always in the UTF-8 encoding even if the named parameter was
+** always in UTF-8 encoding even if the named parameter was
 ** originally specified as UTF-16 in [sqlite3_prepare16()] or
 ** [sqlite3_prepare16_v2()].
 **
@@ -2981,17 +3714,16 @@ SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
 **
 ** INVARIANTS:
 **
-** {F13621} The [sqlite3_bind_parameter_name(S,N)] interface returns
+** {H13621} The [sqlite3_bind_parameter_name(S,N)] interface returns
 **          a UTF-8 rendering of the name of the SQL parameter in
-**          [prepared statement] S having index N, or
+**          the [prepared statement] S having index N, or
 **          NULL if there is no SQL parameter with index N or if the
-**          parameter with index N is an anonymous parameter "?" or
-**          a numbered parameter "?NNN".
+**          parameter with index N is an anonymous parameter "?".
 */
 SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
 
 /*
-** CAPI3REF: Index Of A Parameter With A Given Name {F13640}
+** CAPI3REF: Index Of A Parameter With A Given Name {H13640} 
 **
 ** Return the index of an SQL parameter given its name.  The
 ** index value returned is suitable for use as the second
@@ -3006,62 +3738,56 @@ SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
 **
 ** INVARIANTS:
 **
-** {F13641} The [sqlite3_bind_parameter_index(S,N)] interface returns
-**          the index of SQL parameter in [prepared statement]
+** {H13641} The [sqlite3_bind_parameter_index(S,N)] interface returns
+**          the index of SQL parameter in the [prepared statement]
 **          S whose name matches the UTF-8 string N, or 0 if there is
 **          no match.
 */
 SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
 
 /*
-** CAPI3REF: Reset All Bindings On A Prepared Statement {F13660}
+** CAPI3REF: Reset All Bindings On A Prepared Statement {H13660} 
 **
-** Contrary to the intuition of many, [sqlite3_reset()] does not
-** reset the [sqlite3_bind_blob | bindings] on a 
-** [prepared statement].  Use this routine to
-** reset all host parameters to NULL.
+** Contrary to the intuition of many, [sqlite3_reset()] does not reset
+** the [sqlite3_bind_blob | bindings] on a [prepared statement].
+** Use this routine to reset all host parameters to NULL.
 **
 ** INVARIANTS:
 **
-** {F13661} The [sqlite3_clear_bindings(S)] interface resets all
-**          SQL parameter bindings in [prepared statement] S
-**          back to NULL.
+** {H13661} The [sqlite3_clear_bindings(S)] interface resets all SQL
+**          parameter bindings in the [prepared statement] S back to NULL.
 */
 SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
 
 /*
-** CAPI3REF: Number Of Columns In A Result Set {F13710}
+** CAPI3REF: Number Of Columns In A Result Set {H13710} 
 **
-** Return the number of columns in the result set returned by the 
-** [prepared statement]. This routine returns 0
-** if pStmt is an SQL statement that does not return data (for 
-** example an UPDATE).
+** Return the number of columns in the result set returned by the
+** [prepared statement]. This routine returns 0 if pStmt is an SQL
+** statement that does not return data (for example an [UPDATE]).
 **
 ** INVARIANTS:
 **
-** {F13711} The [sqlite3_column_count(S)] interface returns the number of
-**          columns in the result set generated by the
-**          [prepared statement] S, or 0 if S does not generate
-**          a result set.
+** {H13711} The [sqlite3_column_count(S)] interface returns the number of
+**          columns in the result set generated by the [prepared statement] S,
+**          or 0 if S does not generate a result set.
 */
 SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Column Names In A Result Set {F13720}
+** CAPI3REF: Column Names In A Result Set {H13720} 
 **
 ** These routines return the name assigned to a particular column
-** in the result set of a SELECT statement.  The sqlite3_column_name()
-** interface returns a pointer to a zero-terminated UTF8 string
+** in the result set of a [SELECT] statement.  The sqlite3_column_name()
+** interface returns a pointer to a zero-terminated UTF-8 string
 ** and sqlite3_column_name16() returns a pointer to a zero-terminated
-** UTF16 string.  The first parameter is the
-** [prepared statement] that implements the SELECT statement.
-** The second parameter is the column number.  The left-most column is
-** number 0.
+** UTF-16 string.  The first parameter is the [prepared statement]
+** that implements the [SELECT] statement. The second parameter is the
+** column number.  The leftmost column is number 0.
 **
-** The returned string pointer is valid until either the 
-** [prepared statement] is destroyed by [sqlite3_finalize()]
-** or until the next call sqlite3_column_name() or sqlite3_column_name16()
-** on the same column.
+** The returned string pointer is valid until either the [prepared statement]
+** is destroyed by [sqlite3_finalize()] or until the next call to
+** sqlite3_column_name() or sqlite3_column_name16() on the same column.
 **
 ** If sqlite3_malloc() fails during the processing of either routine
 ** (for example during a conversion from UTF-8 to UTF-16) then a
@@ -3074,136 +3800,124 @@ SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
 **
 ** INVARIANTS:
 **
-** {F13721} A successful invocation of the [sqlite3_column_name(S,N)]
-**          interface returns the name
-**          of the Nth column (where 0 is the left-most column) for the
-**          result set of [prepared statement] S as a
-**          zero-terminated UTF-8 string.
+** {H13721} A successful invocation of the [sqlite3_column_name(S,N)]
+**          interface returns the name of the Nth column (where 0 is
+**          the leftmost column) for the result set of the
+**          [prepared statement] S as a zero-terminated UTF-8 string.
 **
-** {F13723} A successful invocation of the [sqlite3_column_name16(S,N)]
-**          interface returns the name
-**          of the Nth column (where 0 is the left-most column) for the
-**          result set of [prepared statement] S as a
-**          zero-terminated UTF-16 string in the native byte order.
+** {H13723} A successful invocation of the [sqlite3_column_name16(S,N)]
+**          interface returns the name of the Nth column (where 0 is
+**          the leftmost column) for the result set of the
+**          [prepared statement] S as a zero-terminated UTF-16 string
+**          in the native byte order.
 **
-** {F13724} The [sqlite3_column_name()] and [sqlite3_column_name16()]
+** {H13724} The [sqlite3_column_name()] and [sqlite3_column_name16()]
 **          interfaces return a NULL pointer if they are unable to
-**          allocate memory memory to hold there normal return strings.
+**          allocate memory to hold their normal return strings.
 **
-** {F13725} If the N parameter to [sqlite3_column_name(S,N)] or
+** {H13725} If the N parameter to [sqlite3_column_name(S,N)] or
 **          [sqlite3_column_name16(S,N)] is out of range, then the
-**          interfaces returns a NULL pointer.
-** 
-** {F13726} The strings returned by [sqlite3_column_name(S,N)] and
+**          interfaces return a NULL pointer.
+**
+** {H13726} The strings returned by [sqlite3_column_name(S,N)] and
 **          [sqlite3_column_name16(S,N)] are valid until the next
 **          call to either routine with the same S and N parameters
 **          or until [sqlite3_finalize(S)] is called.
 **
-** {F13727} When a result column of a [SELECT] statement contains
-**          an AS clause, the name of that column is the indentifier
+** {H13727} When a result column of a [SELECT] statement contains
+**          an AS clause, the name of that column is the identifier
 **          to the right of the AS keyword.
 */
 SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
 SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
 
 /*
-** CAPI3REF: Source Of Data In A Query Result {F13740}
+** CAPI3REF: Source Of Data In A Query Result {H13740} 
 **
 ** These routines provide a means to determine what column of what
-** table in which database a result of a SELECT statement comes from.
+** table in which database a result of a [SELECT] statement comes from.
 ** The name of the database or table or column can be returned as
-** either a UTF8 or UTF16 string.  The _database_ routines return
+** either a UTF-8 or UTF-16 string.  The _database_ routines return
 ** the database name, the _table_ routines return the table name, and
 ** the origin_ routines return the column name.
-** The returned string is valid until
-** the [prepared statement] is destroyed using
-** [sqlite3_finalize()] or until the same information is requested
+** The returned string is valid until the [prepared statement] is destroyed
+** using [sqlite3_finalize()] or until the same information is requested
 ** again in a different encoding.
 **
 ** The names returned are the original un-aliased names of the
 ** database, table, and column.
 **
 ** The first argument to the following calls is a [prepared statement].
-** These functions return information about the Nth column returned by 
+** These functions return information about the Nth column returned by
 ** the statement, where N is the second function argument.
 **
-** If the Nth column returned by the statement is an expression
-** or subquery and is not a column value, then all of these functions
-** return NULL.  These routine might also return NULL if a memory
-** allocation error occurs.  Otherwise, they return the 
-** name of the attached database, table and column that query result
-** column was extracted from.
+** If the Nth column returned by the statement is an expression or
+** subquery and is not a column value, then all of these functions return
+** NULL.  These routine might also return NULL if a memory allocation error
+** occurs.  Otherwise, they return the name of the attached database, table
+** and column that query result column was extracted from.
 **
 ** As with all other SQLite APIs, those postfixed with "16" return
 ** UTF-16 encoded strings, the other functions return UTF-8. {END}
 **
-** These APIs are only available if the library was compiled with the 
-** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined.
+** These APIs are only available if the library was compiled with the
+** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
 **
-** {U13751}
+** {A13751}
 ** If two or more threads call one or more of these routines against the same
 ** prepared statement and column at the same time then the results are
 ** undefined.
 **
 ** INVARIANTS:
 **
-** {F13741} The [sqlite3_column_database_name(S,N)] interface returns either
-**          the UTF-8 zero-terminated name of the database from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13742} The [sqlite3_column_database_name16(S,N)] interface returns either
-**          the UTF-16 native byte order
-**          zero-terminated name of the database from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13743} The [sqlite3_column_table_name(S,N)] interface returns either
-**          the UTF-8 zero-terminated name of the table from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13744} The [sqlite3_column_table_name16(S,N)] interface returns either
-**          the UTF-16 native byte order
-**          zero-terminated name of the table from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
+** {H13741} The [sqlite3_column_database_name(S,N)] interface returns either
+**          the UTF-8 zero-terminated name of the database from which the
+**          Nth result column of the [prepared statement] S is extracted,
+**          or NULL if the Nth column of S is a general expression
+**          or if unable to allocate memory to store the name.
+**
+** {H13742} The [sqlite3_column_database_name16(S,N)] interface returns either
+**          the UTF-16 native byte order zero-terminated name of the database
+**          from which the Nth result column of the [prepared statement] S is
+**          extracted, or NULL if the Nth column of S is a general expression
+**          or if unable to allocate memory to store the name.
+**
+** {H13743} The [sqlite3_column_table_name(S,N)] interface returns either
+**          the UTF-8 zero-terminated name of the table from which the
+**          Nth result column of the [prepared statement] S is extracted,
+**          or NULL if the Nth column of S is a general expression
+**          or if unable to allocate memory to store the name.
+**
+** {H13744} The [sqlite3_column_table_name16(S,N)] interface returns either
+**          the UTF-16 native byte order zero-terminated name of the table
+**          from which the Nth result column of the [prepared statement] S is
+**          extracted, or NULL if the Nth column of S is a general expression
+**          or if unable to allocate memory to store the name.
+**
+** {H13745} The [sqlite3_column_origin_name(S,N)] interface returns either
+**          the UTF-8 zero-terminated name of the table column from which the
+**          Nth result column of the [prepared statement] S is extracted,
+**          or NULL if the Nth column of S is a general expression
+**          or if unable to allocate memory to store the name.
+**
+** {H13746} The [sqlite3_column_origin_name16(S,N)] interface returns either
+**          the UTF-16 native byte order zero-terminated name of the table
+**          column from which the Nth result column of the
+**          [prepared statement] S is extracted, or NULL if the Nth column
+**          of S is a general expression or if unable to allocate memory
 **          to store the name.
-**          
-** {F13745} The [sqlite3_column_origin_name(S,N)] interface returns either
-**          the UTF-8 zero-terminated name of the table column from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13746} The [sqlite3_column_origin_name16(S,N)] interface returns either
-**          the UTF-16 native byte order
-**          zero-terminated name of the table column from which the 
-**          Nth result column of [prepared statement] S 
-**          is extracted, or NULL if the the Nth column of S is a
-**          general expression or if unable to allocate memory
-**          to store the name.
-**          
-** {F13748} The return values from
-**          [sqlite3_column_database_name|column metadata interfaces]
-**          are valid
-**          for the lifetime of the [prepared statement]
+**
+** {H13748} The return values from
+**          [sqlite3_column_database_name | column metadata interfaces]
+**          are valid for the lifetime of the [prepared statement]
 **          or until the encoding is changed by another metadata
 **          interface call for the same prepared statement and column.
 **
-** LIMITATIONS:
+** ASSUMPTIONS:
 **
-** {U13751} If two or more threads call one or more
-**          [sqlite3_column_database_name|column metadata interfaces]
-**          the same [prepared statement] and result column
+** {A13751} If two or more threads call one or more
+**          [sqlite3_column_database_name | column metadata interfaces]
+**          for the same [prepared statement] and result column
 **          at the same time then the results are undefined.
 */
 SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
@@ -3214,26 +3928,26 @@ SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
 SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
 
 /*
-** CAPI3REF: Declared Datatype Of A Query Result {F13760}
+** CAPI3REF: Declared Datatype Of A Query Result {H13760} 
 **
-** The first parameter is a [prepared statement]. 
-** If this statement is a SELECT statement and the Nth column of the 
-** returned result set of that SELECT is a table column (not an
+** The first parameter is a [prepared statement].
+** If this statement is a [SELECT] statement and the Nth column of the
+** returned result set of that [SELECT] is a table column (not an
 ** expression or subquery) then the declared type of the table
 ** column is returned.  If the Nth column of the result set is an
 ** expression or subquery, then a NULL pointer is returned.
-** The returned string is always UTF-8 encoded.  {END} 
-** For example, in the database schema:
+** The returned string is always UTF-8 encoded. {END}
+**
+** For example, given the database schema:
 **
 ** CREATE TABLE t1(c1 VARIANT);
 **
-** And the following statement compiled:
+** and the following statement to be compiled:
 **
 ** SELECT c1 + 1, c1 FROM t1;
 **
-** Then this routine would return the string "VARIANT" for the second
-** result column (i==1), and a NULL pointer for the first result column
-** (i==0).
+** this routine would return the string "VARIANT" for the second result
+** column (i==1), and a NULL pointer for the first result column (i==0).
 **
 ** SQLite uses dynamic run-time typing.  So just because a column
 ** is declared to contain a particular type does not mean that the
@@ -3244,22 +3958,21 @@ SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
 **
 ** INVARIANTS:
 **
-** {F13761}  A successful call to [sqlite3_column_decltype(S,N)]
-**           returns a zero-terminated UTF-8 string containing the
-**           the declared datatype of the table column that appears
-**           as the Nth column (numbered from 0) of the result set to the
-**           [prepared statement] S.
+** {H13761}  A successful call to [sqlite3_column_decltype(S,N)] returns a
+**           zero-terminated UTF-8 string containing the declared datatype
+**           of the table column that appears as the Nth column (numbered
+**           from 0) of the result set to the [prepared statement] S.
 **
-** {F13762}  A successful call to [sqlite3_column_decltype16(S,N)]
+** {H13762}  A successful call to [sqlite3_column_decltype16(S,N)]
 **           returns a zero-terminated UTF-16 native byte order string
 **           containing the declared datatype of the table column that appears
 **           as the Nth column (numbered from 0) of the result set to the
 **           [prepared statement] S.
 **
-** {F13763}  If N is less than 0 or N is greater than or equal to
-**           the number of columns in [prepared statement] S
+** {H13763}  If N is less than 0 or N is greater than or equal to
+**           the number of columns in the [prepared statement] S,
 **           or if the Nth column of S is an expression or subquery rather
-**           than a table column or if a memory allocation failure
+**           than a table column, or if a memory allocation failure
 **           occurs during encoding conversions, then
 **           calls to [sqlite3_column_decltype(S,N)] or
 **           [sqlite3_column_decltype16(S,N)] return NULL.
@@ -3267,32 +3980,30 @@ SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
 SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
 SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
 
-/* 
-** CAPI3REF:  Evaluate An SQL Statement {F13200}
+/*
+** CAPI3REF: Evaluate An SQL Statement {H13200} 
 **
-** After an [prepared statement] has been prepared with a call
-** to either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or to one of
-** the legacy interfaces [sqlite3_prepare()] or [sqlite3_prepare16()],
-** then this function must be called one or more times to evaluate the 
-** statement.
+** After a [prepared statement] has been prepared using either
+** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
+** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
+** must be called one or more times to evaluate the statement.
 **
-** The details of the behavior of this sqlite3_step() interface depend
+** The details of the behavior of the sqlite3_step() interface depend
 ** on whether the statement was prepared using the newer "v2" interface
 ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
 ** interface [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
 ** new "v2" interface is recommended for new applications but the legacy
 ** interface will continue to be supported.
 **
-** In the lagacy interface, the return value will be either [SQLITE_BUSY], 
+** In the legacy interface, the return value will be either [SQLITE_BUSY],
 ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
-** With the "v2" interface, any of the other [SQLITE_OK | result code]
-** or [SQLITE_IOERR_READ | extended result code] might be returned as
-** well.
+** With the "v2" interface, any of the other [result codes] or
+** [extended result codes] might be returned as well.
 **
 ** [SQLITE_BUSY] means that the database engine was unable to acquire the
-** database locks it needs to do its job.  If the statement is a COMMIT
+** database locks it needs to do its job.  If the statement is a [COMMIT]
 ** or occurs outside of an explicit transaction, then you can retry the
-** statement.  If the statement is not a COMMIT and occurs within a
+** statement.  If the statement is not a [COMMIT] and occurs within a
 ** explicit transaction then you should rollback the transaction before
 ** continuing.
 **
@@ -3301,16 +4012,15 @@ SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
 ** machine without first calling [sqlite3_reset()] to reset the virtual
 ** machine back to its initial state.
 **
-** If the SQL statement being executed returns any data, then 
-** [SQLITE_ROW] is returned each time a new row of data is ready
-** for processing by the caller. The values may be accessed using
-** the [sqlite3_column_int | column access functions].
+** If the SQL statement being executed returns any data, then [SQLITE_ROW]
+** is returned each time a new row of data is ready for processing by the
+** caller. The values may be accessed using the [column access functions].
 ** sqlite3_step() is called again to retrieve the next row of data.
-** 
+**
 ** [SQLITE_ERROR] means that a run-time error (such as a constraint
 ** violation) has occurred.  sqlite3_step() should not be called again on
 ** the VM. More information may be found by calling [sqlite3_errmsg()].
-** With the legacy interface, a more specific error code (example:
+** With the legacy interface, a more specific error code (for example,
 ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
 ** can be obtained by calling [sqlite3_reset()] on the
 ** [prepared statement].  In the "v2" interface,
@@ -3318,80 +4028,75 @@ SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
 **
 ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
 ** Perhaps it was called on a [prepared statement] that has
-** already been [sqlite3_finalize | finalized] or on one that had 
+** already been [sqlite3_finalize | finalized] or on one that had
 ** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
 ** be the case that the same database connection is being used by two or
 ** more threads at the same moment in time.
 **
-** Goofy Interface Alert:
-** In the legacy interface, 
-** the sqlite3_step() API always returns a generic error code,
-** [SQLITE_ERROR], following any error other than [SQLITE_BUSY]
-** and [SQLITE_MISUSE].  You must call [sqlite3_reset()] or
-** [sqlite3_finalize()] in order to find one of the specific
-** [error codes] that better describes the error.
+** Goofy Interface Alert: In the legacy interface, the sqlite3_step()
+** API always returns a generic error code, [SQLITE_ERROR], following any
+** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
+** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
+** specific [error codes] that better describes the error.
 ** We admit that this is a goofy design.  The problem has been fixed
 ** with the "v2" interface.  If you prepare all of your SQL statements
 ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
-** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()], then the 
-** more specific [error codes] are returned directly
+** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
+** then the more specific [error codes] are returned directly
 ** by sqlite3_step().  The use of the "v2" interface is recommended.
 **
 ** INVARIANTS:
 **
-** {F13202}  If [prepared statement] S is ready to be
-**           run, then [sqlite3_step(S)] advances that prepared statement
-**           until to completion or until it is ready to return another
-**           row of the result set or an interrupt or run-time error occurs.
+** {H13202}  If the [prepared statement] S is ready to be run, then
+**           [sqlite3_step(S)] advances that prepared statement until
+**           completion or until it is ready to return another row of the
+**           result set, or until an [sqlite3_interrupt | interrupt]
+**           or a run-time error occurs.
 **
-** {F15304}  When a call to [sqlite3_step(S)] causes the 
-**           [prepared statement] S to run to completion,
-**           the function returns [SQLITE_DONE].
+** {H15304}  When a call to [sqlite3_step(S)] causes the [prepared statement]
+**           S to run to completion, the function returns [SQLITE_DONE].
 **
-** {F15306}  When a call to [sqlite3_step(S)] stops because it is ready
-**           to return another row of the result set, it returns
-**           [SQLITE_ROW].
+** {H15306}  When a call to [sqlite3_step(S)] stops because it is ready to
+**           return another row of the result set, it returns [SQLITE_ROW].
 **
-** {F15308}  If a call to [sqlite3_step(S)] encounters an
-**           [sqlite3_interrupt|interrupt] or a run-time error,
-**           it returns an appropraite error code that is not one of
+** {H15308}  If a call to [sqlite3_step(S)] encounters an
+**           [sqlite3_interrupt | interrupt] or a run-time error,
+**           it returns an appropriate error code that is not one of
 **           [SQLITE_OK], [SQLITE_ROW], or [SQLITE_DONE].
 **
-** {F15310}  If an [sqlite3_interrupt|interrupt] or run-time error
+** {H15310}  If an [sqlite3_interrupt | interrupt] or a run-time error
 **           occurs during a call to [sqlite3_step(S)]
 **           for a [prepared statement] S created using
 **           legacy interfaces [sqlite3_prepare()] or
-**           [sqlite3_prepare16()] then the function returns either
+**           [sqlite3_prepare16()], then the function returns either
 **           [SQLITE_ERROR], [SQLITE_BUSY], or [SQLITE_MISUSE].
 */
 SQLITE_API int sqlite3_step(sqlite3_stmt*);
 
 /*
-** CAPI3REF: Number of columns in a result set {F13770}
+** CAPI3REF: Number of columns in a result set {H13770} 
 **
-** Return the number of values in the current row of the result set.
+** Returns the number of values in the current row of the result set.
 **
 ** INVARIANTS:
 **
-** {F13771}  After a call to [sqlite3_step(S)] that returns
-**           [SQLITE_ROW], the [sqlite3_data_count(S)] routine
-**           will return the same value as the
-**           [sqlite3_column_count(S)] function.
+** {H13771}  After a call to [sqlite3_step(S)] that returns [SQLITE_ROW],
+**           the [sqlite3_data_count(S)] routine will return the same value
+**           as the [sqlite3_column_count(S)] function.
 **
-** {F13772}  After [sqlite3_step(S)] has returned any value other than
-**           [SQLITE_ROW] or before [sqlite3_step(S)] has been 
-**           called on the [prepared statement] for
-**           the first time since it was [sqlite3_prepare|prepared]
-**           or [sqlite3_reset|reset], the [sqlite3_data_count(S)]
-**           routine returns zero.
+** {H13772}  After [sqlite3_step(S)] has returned any value other than
+**           [SQLITE_ROW] or before [sqlite3_step(S)] has been called on the
+**           [prepared statement] for the first time since it was
+**           [sqlite3_prepare | prepared] or [sqlite3_reset | reset],
+**           the [sqlite3_data_count(S)] routine returns zero.
 */
 SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Fundamental Datatypes {F10265}
+** CAPI3REF: Fundamental Datatypes {H10265} 
 ** KEYWORDS: SQLITE_TEXT
 **
-** {F10266}Every value in SQLite has one of five fundamental datatypes:
+** {H10266} Every value in SQLite has one of five fundamental datatypes:
 **
 ** 
      
 ** 
    •  64-bit signed integer
@@ -3405,7 +4110,7 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 **
 ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
 ** for a completely different meaning.  Software that links against both
-** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT not
+** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
 ** SQLITE_TEXT.
 */
 #define SQLITE_INTEGER  1
@@ -3420,33 +4125,31 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 #define SQLITE3_TEXT     3
 
 /*
-** CAPI3REF: Results Values From A Query {F13800}
+** CAPI3REF: Result Values From A Query {H13800} 
+** KEYWORDS: {column access functions}
 **
 ** These routines form the "result set query" interface.
 **
-** These routines return information about
-** a single column of the current result row of a query.  In every
-** case the first argument is a pointer to the 
-** [prepared statement] that is being
-** evaluated (the [sqlite3_stmt*] that was returned from 
-** [sqlite3_prepare_v2()] or one of its variants) and
-** the second argument is the index of the column for which information 
-** should be returned.  The left-most column of the result set
-** has an index of 0.
-**
-** If the SQL statement is not currently point to a valid row, or if the
-** the column index is out of range, the result is undefined. 
+** These routines return information about a single column of the current
+** result row of a query.  In every case the first argument is a pointer
+** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
+** that was returned from [sqlite3_prepare_v2()] or one of its variants)
+** and the second argument is the index of the column for which information
+** should be returned.  The leftmost column of the result set has the index 0.
+**
+** If the SQL statement does not currently point to a valid row, or if the
+** column index is out of range, the result is undefined.
 ** These routines may only be called when the most recent call to
 ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
-** [sqlite3_reset()] nor [sqlite3_finalize()] has been call subsequently.
+** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
 ** If any of these routines are called after [sqlite3_reset()] or
 ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
 ** something other than [SQLITE_ROW], the results are undefined.
 ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
 ** are called from a different thread while any of these routines
-** are pending, then the results are undefined.  
+** are pending, then the results are undefined.
 **
-** The sqlite3_column_type() routine returns 
+** The sqlite3_column_type() routine returns the
 ** [SQLITE_INTEGER | datatype code] for the initial data type
 ** of the result column.  The returned value is one of [SQLITE_INTEGER],
 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].  The value
@@ -3456,7 +4159,7 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 ** versions of SQLite may change the behavior of sqlite3_column_type()
 ** following a type conversion.
 **
-** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() 
+** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
 ** routine returns the number of bytes in that BLOB or string.
 ** If the result is a UTF-16 string, then sqlite3_column_bytes() converts
 ** the string to UTF-8 and then returns the number of bytes.
@@ -3469,18 +4172,26 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 **
 ** Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
 ** even empty strings, are always zero terminated.  The return
-** value from sqlite3_column_blob() for a zero-length blob is an arbitrary
+** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary
 ** pointer, possibly even a NULL pointer.
 **
 ** The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
-** but leaves the result in UTF-16 in native byte order instead of UTF-8.  
+** but leaves the result in UTF-16 in native byte order instead of UTF-8.
 ** The zero terminator is not included in this count.
 **
+** The object returned by [sqlite3_column_value()] is an
+** [unprotected sqlite3_value] object.  An unprotected sqlite3_value object
+** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
+** If the [unprotected sqlite3_value] object returned by
+** [sqlite3_column_value()] is used in any other way, including calls
+** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
+** or [sqlite3_value_bytes()], then the behavior is undefined.
+**
 ** These routines attempt to convert the value where appropriate.  For
 ** example, if the internal representation is FLOAT and a text result
-** is requested, [sqlite3_snprintf()] is used internally to do the conversion
-** automatically.  The following table details the conversions that
-** are applied:
+** is requested, [sqlite3_snprintf()] is used internally to perform the
+** conversion automatically.  The following table details the conversions
+** that are applied:
 **
 ** 
      
 ** 
@@ -3492,7 +4203,7 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 ** 
        NULL       BLOB     Result is NULL pointer
 ** 
       INTEGER    FLOAT     Convert from integer to float
 ** 
       INTEGER     TEXT     ASCII rendering of the integer
-** 
       INTEGER     BLOB     Same as for INTEGER->TEXT
+** 
       INTEGER     BLOB     Same as INTEGER->TEXT
 ** 
        FLOAT    INTEGER    Convert from float to integer
 ** 
        FLOAT      TEXT     ASCII rendering of the float
 ** 
        FLOAT      BLOB     Same as FLOAT->TEXT
@@ -3507,57 +4218,56 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 **
 ** The table above makes reference to standard C library functions atoi()
 ** and atof().  SQLite does not really use these functions.  It has its
-** on equavalent internal routines.  The atoi() and atof() names are
+** own equivalent internal routines.  The atoi() and atof() names are
 ** used in the table for brevity and because they are familiar to most
 ** C programmers.
 **
 ** Note that when type conversions occur, pointers returned by prior
 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
-** sqlite3_column_text16() may be invalidated. 
+** sqlite3_column_text16() may be invalidated.
 ** Type conversions and pointer invalidations might occur
 ** in the following cases:
 **
 ** 
        
-** 
      •   The initial content is a BLOB and sqlite3_column_text() 
-**          or sqlite3_column_text16() is called.  A zero-terminator might
-**          need to be added to the string.
        • 
-**
-** 
      •   The initial content is UTF-8 text and sqlite3_column_bytes16() or
-**          sqlite3_column_text16() is called.  The content must be converted
-**          to UTF-16.
        • 
-**
-** 
      •   The initial content is UTF-16 text and sqlite3_column_bytes() or
-**          sqlite3_column_text() is called.  The content must be converted
-**          to UTF-8.
        • 
+** 
      •  The initial content is a BLOB and sqlite3_column_text() or
+**      sqlite3_column_text16() is called.  A zero-terminator might
+**      need to be added to the string.
        • 
+** 
      •  The initial content is UTF-8 text and sqlite3_column_bytes16() or
+**      sqlite3_column_text16() is called.  The content must be converted
+**      to UTF-16.
        • 
+** 
      •  The initial content is UTF-16 text and sqlite3_column_bytes() or
+**      sqlite3_column_text() is called.  The content must be converted
+**      to UTF-8.
        • 
 ** 
      
 **
 ** Conversions between UTF-16be and UTF-16le are always done in place and do
 ** not invalidate a prior pointer, though of course the content of the buffer
 ** that the prior pointer points to will have been modified.  Other kinds
-** of conversion are done in place when it is possible, but sometime it is
-** not possible and in those cases prior pointers are invalidated.  
+** of conversion are done in place when it is possible, but sometimes they
+** are not possible and in those cases prior pointers are invalidated.
 **
 ** The safest and easiest to remember policy is to invoke these routines
 ** in one of the following ways:
 **
-**  
        
+** 
          
 **  
        • sqlite3_column_text() followed by sqlite3_column_bytes()
          • 
 **  
        • sqlite3_column_blob() followed by sqlite3_column_bytes()
          • 
 **  
        • sqlite3_column_text16() followed by sqlite3_column_bytes16()
          • 
-**  
        
+** 
      
 **
-** In other words, you should call sqlite3_column_text(), sqlite3_column_blob(),
-** or sqlite3_column_text16() first to force the result into the desired
-** format, then invoke sqlite3_column_bytes() or sqlite3_column_bytes16() to
-** find the size of the result.  Do not mix call to sqlite3_column_text() or
-** sqlite3_column_blob() with calls to sqlite3_column_bytes16().  And do not
-** mix calls to sqlite3_column_text16() with calls to sqlite3_column_bytes().
+** In other words, you should call sqlite3_column_text(),
+** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
+** into the desired format, then invoke sqlite3_column_bytes() or
+** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
+** to sqlite3_column_text() or sqlite3_column_blob() with calls to
+** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
+** with calls to sqlite3_column_bytes().
 **
 ** The pointers returned are valid until a type conversion occurs as
 ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
 ** [sqlite3_finalize()] is called.  The memory space used to hold strings
-** and blobs is freed automatically.  Do not pass the pointers returned
-** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into 
+** and BLOBs is freed automatically.  Do not pass the pointers returned
+** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
 ** [sqlite3_free()].
 **
 ** If a memory allocation error occurs during the evaluation of any
@@ -3568,58 +4278,58 @@ SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 **
 ** INVARIANTS:
 **
-** {F13803} The [sqlite3_column_blob(S,N)] interface converts the
+** {H13803} The [sqlite3_column_blob(S,N)] interface converts the
 **          Nth column in the current row of the result set for
-**          [prepared statement] S into a blob and then returns a
+**          the [prepared statement] S into a BLOB and then returns a
 **          pointer to the converted value.
 **
-** {F13806} The [sqlite3_column_bytes(S,N)] interface returns the
-**          number of bytes in the blob or string (exclusive of the
+** {H13806} The [sqlite3_column_bytes(S,N)] interface returns the
+**          number of bytes in the BLOB or string (exclusive of the
 **          zero terminator on the string) that was returned by the
 **          most recent call to [sqlite3_column_blob(S,N)] or
 **          [sqlite3_column_text(S,N)].
 **
-** {F13809} The [sqlite3_column_bytes16(S,N)] interface returns the
+** {H13809} The [sqlite3_column_bytes16(S,N)] interface returns the
 **          number of bytes in the string (exclusive of the
 **          zero terminator on the string) that was returned by the
 **          most recent call to [sqlite3_column_text16(S,N)].
 **
-** {F13812} The [sqlite3_column_double(S,N)] interface converts the
-**          Nth column in the current row of the result set for
+** {H13812} The [sqlite3_column_double(S,N)] interface converts the
+**          Nth column in the current row of the result set for the
 **          [prepared statement] S into a floating point value and
 **          returns a copy of that value.
 **
-** {F13815} The [sqlite3_column_int(S,N)] interface converts the
-**          Nth column in the current row of the result set for
+** {H13815} The [sqlite3_column_int(S,N)] interface converts the
+**          Nth column in the current row of the result set for the
 **          [prepared statement] S into a 64-bit signed integer and
 **          returns the lower 32 bits of that integer.
 **
-** {F13818} The [sqlite3_column_int64(S,N)] interface converts the
-**          Nth column in the current row of the result set for
+** {H13818} The [sqlite3_column_int64(S,N)] interface converts the
+**          Nth column in the current row of the result set for the
 **          [prepared statement] S into a 64-bit signed integer and
 **          returns a copy of that integer.
 **
-** {F13821} The [sqlite3_column_text(S,N)] interface converts the
+** {H13821} The [sqlite3_column_text(S,N)] interface converts the
 **          Nth column in the current row of the result set for
-**          [prepared statement] S into a zero-terminated UTF-8 
+**          the [prepared statement] S into a zero-terminated UTF-8
 **          string and returns a pointer to that string.
 **
-** {F13824} The [sqlite3_column_text16(S,N)] interface converts the
-**          Nth column in the current row of the result set for
+** {H13824} The [sqlite3_column_text16(S,N)] interface converts the
+**          Nth column in the current row of the result set for the
 **          [prepared statement] S into a zero-terminated 2-byte
-**          aligned UTF-16 native byte order
-**          string and returns a pointer to that string.
+**          aligned UTF-16 native byte order string and returns
+**          a pointer to that string.
 **
-** {F13827} The [sqlite3_column_type(S,N)] interface returns
+** {H13827} The [sqlite3_column_type(S,N)] interface returns
 **          one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT],
 **          [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for
 **          the Nth column in the current row of the result set for
-**          [prepared statement] S.
+**          the [prepared statement] S.
 **
-** {F13830} The [sqlite3_column_value(S,N)] interface returns a
-**          pointer to the [sqlite3_value] object that for the
+** {H13830} The [sqlite3_column_value(S,N)] interface returns a
+**          pointer to an [unprotected sqlite3_value] object for the
 **          Nth column in the current row of the result set for
-**          [prepared statement] S.
+**          the [prepared statement] S.
 */
 SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
 SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
@@ -3633,90 +4343,89 @@ SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
 SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
 
 /*
-** CAPI3REF: Destroy A Prepared Statement Object {F13300}
+** CAPI3REF: Destroy A Prepared Statement Object {H13300} 
 **
-** The sqlite3_finalize() function is called to delete a 
-** [prepared statement]. If the statement was
-** executed successfully, or not executed at all, then SQLITE_OK is returned.
-** If execution of the statement failed then an 
-** [error code] or [extended error code]
-** is returned. 
+** The sqlite3_finalize() function is called to delete a [prepared statement].
+** If the statement was executed successfully or not executed at all, then
+** SQLITE_OK is returned. If execution of the statement failed then an
+** [error code] or [extended error code] is returned.
 **
 ** This routine can be called at any point during the execution of the
-** [prepared statement].  If the virtual machine has not 
+** [prepared statement].  If the virtual machine has not
 ** completed execution when this routine is called, that is like
-** encountering an error or an interrupt.  (See [sqlite3_interrupt()].) 
-** Incomplete updates may be rolled back and transactions cancelled,  
-** depending on the circumstances, and the 
+** encountering an error or an [sqlite3_interrupt | interrupt].
+** Incomplete updates may be rolled back and transactions canceled,
+** depending on the circumstances, and the
 ** [error code] returned will be [SQLITE_ABORT].
 **
 ** INVARIANTS:
 **
-** {F11302} The [sqlite3_finalize(S)] interface destroys the
+** {H11302} The [sqlite3_finalize(S)] interface destroys the
 **          [prepared statement] S and releases all
 **          memory and file resources held by that object.
 **
-** {F11304} If the most recent call to [sqlite3_step(S)] for the
+** {H11304} If the most recent call to [sqlite3_step(S)] for the
 **          [prepared statement] S returned an error,
 **          then [sqlite3_finalize(S)] returns that same error.
 */
 SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Reset A Prepared Statement Object {F13330}
+** CAPI3REF: Reset A Prepared Statement Object {H13330} 
 **
-** The sqlite3_reset() function is called to reset a 
-** [prepared statement] object.
-** back to its initial state, ready to be re-executed.
+** The sqlite3_reset() function is called to reset a [prepared statement]
+** object back to its initial state, ready to be re-executed.
 ** Any SQL statement variables that had values bound to them using
 ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
 ** Use [sqlite3_clear_bindings()] to reset the bindings.
 **
-** {F11332} The [sqlite3_reset(S)] interface resets the [prepared statement] S
+** {H11332} The [sqlite3_reset(S)] interface resets the [prepared statement] S
 **          back to the beginning of its program.
 **
-** {F11334} If the most recent call to [sqlite3_step(S)] for 
+** {H11334} If the most recent call to [sqlite3_step(S)] for the
 **          [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
 **          or if [sqlite3_step(S)] has never before been called on S,
 **          then [sqlite3_reset(S)] returns [SQLITE_OK].
 **
-** {F11336} If the most recent call to [sqlite3_step(S)] for
+** {H11336} If the most recent call to [sqlite3_step(S)] for the
 **          [prepared statement] S indicated an error, then
 **          [sqlite3_reset(S)] returns an appropriate [error code].
 **
-** {F11338} The [sqlite3_reset(S)] interface does not change the values
-**          of any [sqlite3_bind_blob|bindings] on [prepared statement] S.
+** {H11338} The [sqlite3_reset(S)] interface does not change the values
+**          of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
 */
 SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Create Or Redefine SQL Functions {F16100}
-** KEYWORDS: {function creation routines} 
+** CAPI3REF: Create Or Redefine SQL Functions {H16100} 
+** KEYWORDS: {function creation routines}
+** KEYWORDS: {application-defined SQL function}
+** KEYWORDS: {application-defined SQL functions}
 **
-** These two functions (collectively known as
-** "function creation routines") are used to add SQL functions or aggregates
-** or to redefine the behavior of existing SQL functions or aggregates.  The
-** difference only between the two is that the second parameter, the
-** name of the (scalar) function or aggregate, is encoded in UTF-8 for
-** sqlite3_create_function() and UTF-16 for sqlite3_create_function16().
+** These two functions (collectively known as "function creation routines")
+** are used to add SQL functions or aggregates or to redefine the behavior
+** of existing SQL functions or aggregates.  The only difference between the
+** two is that the second parameter, the name of the (scalar) function or
+** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16
+** for sqlite3_create_function16().
 **
 ** The first parameter is the [database connection] to which the SQL
-** function is to be added.  If a single
-** program uses more than one [database connection] internally, then SQL
-** functions must be added individually to each [database connection].
-**
-** The second parameter is the name of the SQL function to be created
-** or redefined.
-** The length of the name is limited to 255 bytes, exclusive of the 
-** zero-terminator.  Note that the name length limit is in bytes, not
+** function is to be added.  If a single program uses more than one database
+** connection internally, then SQL functions must be added individually to
+** each database connection.
+**
+** The second parameter is the name of the SQL function to be created or
+** redefined.  The length of the name is limited to 255 bytes, exclusive of
+** the zero-terminator.  Note that the name length limit is in bytes, not
 ** characters.  Any attempt to create a function with a longer name
-** will result in an SQLITE_ERROR error.
+** will result in [SQLITE_ERROR] being returned.
 **
-** The third parameter is the number of arguments that the SQL function or
+** The third parameter (nArg)
+** is the number of arguments that the SQL function or
 ** aggregate takes. If this parameter is negative, then the SQL function or
 ** aggregate may take any number of arguments.
 **
-** The fourth parameter, eTextRep, specifies what 
+** The fourth parameter, eTextRep, specifies what
 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
 ** its parameters.  Any SQL function implementation should be able to work
 ** work with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
@@ -3725,88 +4434,109 @@ SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
 ** times with the same function but with different values of eTextRep.
 ** When multiple implementations of the same function are available, SQLite
 ** will pick the one that involves the least amount of data conversion.
-** If there is only a single implementation which does not care what
-** text encoding is used, then the fourth argument should be
-** [SQLITE_ANY].
+** If there is only a single implementation which does not care what text
+** encoding is used, then the fourth argument should be [SQLITE_ANY].
 **
-** The fifth parameter is an arbitrary pointer.  The implementation
-** of the function can gain access to this pointer using
-** [sqlite3_user_data()].
+** The fifth parameter is an arbitrary pointer.  The implementation of the
+** function can gain access to this pointer using [sqlite3_user_data()].
 **
 ** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
-** pointers to C-language functions that implement the SQL
-** function or aggregate. A scalar SQL function requires an implementation of
-** the xFunc callback only, NULL pointers should be passed as the xStep
-** and xFinal parameters. An aggregate SQL function requires an implementation
-** of xStep and xFinal and NULL should be passed for xFunc. To delete an
-** existing SQL function or aggregate, pass NULL for all three function
-** callback.
+** pointers to C-language functions that implement the SQL function or
+** aggregate. A scalar SQL function requires an implementation of the xFunc
+** callback only, NULL pointers should be passed as the xStep and xFinal
+** parameters. An aggregate SQL function requires an implementation of xStep
+** and xFinal and NULL should be passed for xFunc. To delete an existing
+** SQL function or aggregate, pass NULL for all three function callbacks.
 **
 ** It is permitted to register multiple implementations of the same
 ** functions with the same name but with either differing numbers of
-** arguments or differing perferred text encodings.  SQLite will use
+** arguments or differing preferred text encodings.  SQLite will use
 ** the implementation most closely matches the way in which the
-** SQL function is used.
+** SQL function is used.  A function implementation with a non-negative
+** nArg parameter is a better match than a function implementation with
+** a negative nArg.  A function where the preferred text encoding
+** matches the database encoding is a better
+** match than a function where the encoding is different.  
+** A function where the encoding difference is between UTF16le and UTF16be
+** is a closer match than a function where the encoding difference is
+** between UTF8 and UTF16.
+**
+** Built-in functions may be overloaded by new application-defined functions.
+** The first application-defined function with a given name overrides all
+** built-in functions in the same [database connection] with the same name.
+** Subsequent application-defined functions of the same name only override 
+** prior application-defined functions that are an exact match for the
+** number of parameters and preferred encoding.
+**
+** An application-defined function is permitted to call other
+** SQLite interfaces.  However, such calls must not
+** close the database connection nor finalize or reset the prepared
+** statement in which the function is running.
 **
 ** INVARIANTS:
 **
-** {F16103} The [sqlite3_create_function16()] interface behaves exactly
-**          like [sqlite3_create_function()] in every way except that it
-**          interprets the zFunctionName argument as
-**          zero-terminated UTF-16 native byte order instead of as a
-**          zero-terminated UTF-8.
+** {H16103} The [sqlite3_create_function16(D,X,...)] interface shall behave
+**          as [sqlite3_create_function(D,X,...)] in every way except that it
+**          interprets the X argument as zero-terminated UTF-16
+**          native byte order instead of as zero-terminated UTF-8.
 **
-** {F16106} A successful invocation of
-**          the [sqlite3_create_function(D,X,N,E,...)] interface registers
-**          or replaces callback functions in [database connection] D
+** {H16106} A successful invocation of the
+**          [sqlite3_create_function(D,X,N,E,...)] interface shall register
+**          or replaces callback functions in the [database connection] D
 **          used to implement the SQL function named X with N parameters
-**          and having a perferred text encoding of E.
+**          and having a preferred text encoding of E.
 **
-** {F16109} A successful call to [sqlite3_create_function(D,X,N,E,P,F,S,L)]
-**          replaces the P, F, S, and L values from any prior calls with
+** {H16109} A successful call to [sqlite3_create_function(D,X,N,E,P,F,S,L)]
+**          shall replace the P, F, S, and L values from any prior calls with
 **          the same D, X, N, and E values.
 **
-** {F16112} The [sqlite3_create_function(D,X,...)] interface fails with
-**          a return code of [SQLITE_ERROR] if the SQL function name X is
+** {H16112} The [sqlite3_create_function(D,X,...)] interface shall fail
+**          if the SQL function name X is
 **          longer than 255 bytes exclusive of the zero terminator.
 **
-** {F16118} Either F must be NULL and S and L are non-NULL or else F
-**          is non-NULL and S and L are NULL, otherwise
-**          [sqlite3_create_function(D,X,N,E,P,F,S,L)] returns [SQLITE_ERROR].
+** {H16118} The [sqlite3_create_function(D,X,N,E,P,F,S,L)] interface
+**          shall fail unless either F is NULL and S and L are non-NULL or
+***         F is non-NULL and S and L are NULL.
 **
-** {F16121} The [sqlite3_create_function(D,...)] interface fails with an
+** {H16121} The [sqlite3_create_function(D,...)] interface shall fails with an
 **          error code of [SQLITE_BUSY] if there exist [prepared statements]
 **          associated with the [database connection] D.
 **
-** {F16124} The [sqlite3_create_function(D,X,N,...)] interface fails with an
-**          error code of [SQLITE_ERROR] if parameter N (specifying the number
-**          of arguments to the SQL function being registered) is less
+** {H16124} The [sqlite3_create_function(D,X,N,...)] interface shall fail with
+**          an error code of [SQLITE_ERROR] if parameter N is less
 **          than -1 or greater than 127.
 **
-** {F16127} When N is non-negative, the [sqlite3_create_function(D,X,N,...)]
-**          interface causes callbacks to be invoked for the SQL function
+** {H16127} When N is non-negative, the [sqlite3_create_function(D,X,N,...)]
+**          interface shall register callbacks to be invoked for the
+**          SQL function
 **          named X when the number of arguments to the SQL function is
 **          exactly N.
 **
-** {F16130} When N is -1, the [sqlite3_create_function(D,X,N,...)]
-**          interface causes callbacks to be invoked for the SQL function
-**          named X with any number of arguments.
+** {H16130} When N is -1, the [sqlite3_create_function(D,X,N,...)]
+**          interface shall register callbacks to be invoked for the SQL
+**          function named X with any number of arguments.
 **
-** {F16133} When calls to [sqlite3_create_function(D,X,N,...)]
+** {H16133} When calls to [sqlite3_create_function(D,X,N,...)]
 **          specify multiple implementations of the same function X
 **          and when one implementation has N>=0 and the other has N=(-1)
-**          the implementation with a non-zero N is preferred.
+**          the implementation with a non-zero N shall be preferred.
 **
-** {F16136} When calls to [sqlite3_create_function(D,X,N,E,...)]
+** {H16136} When calls to [sqlite3_create_function(D,X,N,E,...)]
 **          specify multiple implementations of the same function X with
 **          the same number of arguments N but with different
 **          encodings E, then the implementation where E matches the
-**          database encoding is preferred.
+**          database encoding shall preferred.
 **
-** {F16139} For an aggregate SQL function created using
-**          [sqlite3_create_function(D,X,N,E,P,0,S,L)] the finializer
-**          function L will always be invoked exactly once if the
+** {H16139} For an aggregate SQL function created using
+**          [sqlite3_create_function(D,X,N,E,P,0,S,L)] the finalizer
+**          function L shall always be invoked exactly once if the
 **          step function S is called one or more times.
+**
+** {H16142} When SQLite invokes either the xFunc or xStep function of
+**          an application-defined SQL function or aggregate created
+**          by [sqlite3_create_function()] or [sqlite3_create_function16()],
+**          then the array of [sqlite3_value] objects passed as the
+**          third parameter shall be [protected sqlite3_value] objects.
 */
 SQLITE_API int sqlite3_create_function(
   sqlite3 *db,
@@ -3830,7 +4560,7 @@ SQLITE_API int sqlite3_create_function16(
 );
 
 /*
-** CAPI3REF: Text Encodings {F10267}
+** CAPI3REF: Text Encodings {H10267}  
 **
 ** These constant define integer codes that represent the various
 ** text encodings supported by SQLite.
@@ -3843,23 +4573,26 @@ SQLITE_API int sqlite3_create_function16(
 #define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */
 
 /*
-** CAPI3REF: Obsolete Functions
+** CAPI3REF: Deprecated Functions
+** DEPRECATED
 **
-** These functions are all now obsolete.  In order to maintain
-** backwards compatibility with older code, we continue to support
-** these functions.  However, new development projects should avoid
+** These functions are [deprecated].  In order to maintain
+** backwards compatibility with older code, these functions continue 
+** to be supported.  However, new applications should avoid
 ** the use of these functions.  To help encourage people to avoid
 ** using these functions, we are not going to tell you want they do.
 */
-SQLITE_API int sqlite3_aggregate_count(sqlite3_context*);
-SQLITE_API int sqlite3_expired(sqlite3_stmt*);
-SQLITE_API int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
-SQLITE_API int sqlite3_global_recover(void);
-SQLITE_API void sqlite3_thread_cleanup(void);
-SQLITE_API int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
+#ifndef SQLITE_OMIT_DEPRECATED
+SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
+SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
+#endif
 
 /*
-** CAPI3REF: Obtaining SQL Function Parameter Values {F15100}
+** CAPI3REF: Obtaining SQL Function Parameter Values {H15100} 
 **
 ** The C-language implementation of SQL functions and aggregates uses
 ** this set of interface routines to access the parameter values on
@@ -3869,102 +4602,101 @@ SQLITE_API int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlit
 ** to [sqlite3_create_function()] and [sqlite3_create_function16()]
 ** define callbacks that implement the SQL functions and aggregates.
 ** The 4th parameter to these callbacks is an array of pointers to
-** [sqlite3_value] objects.  There is one [sqlite3_value] object for
+** [protected sqlite3_value] objects.  There is one [sqlite3_value] object for
 ** each parameter to the SQL function.  These routines are used to
 ** extract values from the [sqlite3_value] objects.
 **
-** These routines work just like the corresponding 
-** [sqlite3_column_blob | sqlite3_column_* routines] except that 
-** these routines take a single [sqlite3_value*] pointer instead
-** of an [sqlite3_stmt*] pointer and an integer column number.
+** These routines work only with [protected sqlite3_value] objects.
+** Any attempt to use these routines on an [unprotected sqlite3_value]
+** object results in undefined behavior.
 **
-** The sqlite3_value_text16() interface extracts a UTF16 string
+** These routines work just like the corresponding [column access functions]
+** except that  these routines take a single [protected sqlite3_value] object
+** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
+**
+** The sqlite3_value_text16() interface extracts a UTF-16 string
 ** in the native byte-order of the host machine.  The
 ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
-** extract UTF16 strings as big-endian and little-endian respectively.
+** extract UTF-16 strings as big-endian and little-endian respectively.
 **
 ** The sqlite3_value_numeric_type() interface attempts to apply
 ** numeric affinity to the value.  This means that an attempt is
 ** made to convert the value to an integer or floating point.  If
 ** such a conversion is possible without loss of information (in other
-** words if the value is a string that looks like a number)
-** then the conversion is done.  Otherwise no conversion occurs.  The 
-** [SQLITE_INTEGER | datatype] after conversion is returned.
+** words, if the value is a string that looks like a number)
+** then the conversion is performed.  Otherwise no conversion occurs.
+** The [SQLITE_INTEGER | datatype] after conversion is returned.
 **
-** Please pay particular attention to the fact that the pointer that
-** is returned from [sqlite3_value_blob()], [sqlite3_value_text()], or
+** Please pay particular attention to the fact that the pointer returned
+** from [sqlite3_value_blob()], [sqlite3_value_text()], or
 ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
 ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
-** or [sqlite3_value_text16()].  
+** or [sqlite3_value_text16()].
 **
 ** These routines must be called from the same thread as
-** the SQL function that supplied the sqlite3_value* parameters.
-** Or, if the sqlite3_value* argument comes from the [sqlite3_column_value()]
-** interface, then these routines should be called from the same thread
-** that ran [sqlite3_column_value()].
-**
+** the SQL function that supplied the [sqlite3_value*] parameters.
 **
 ** INVARIANTS:
 **
-** {F15103} The [sqlite3_value_blob(V)] interface converts the
-**          [sqlite3_value] object V into a blob and then returns a
-**          pointer to the converted value.
+** {H15103} The [sqlite3_value_blob(V)] interface converts the
+**          [protected sqlite3_value] object V into a BLOB and then
+**          returns a pointer to the converted value.
 **
-** {F15106} The [sqlite3_value_bytes(V)] interface returns the
-**          number of bytes in the blob or string (exclusive of the
+** {H15106} The [sqlite3_value_bytes(V)] interface returns the
+**          number of bytes in the BLOB or string (exclusive of the
 **          zero terminator on the string) that was returned by the
 **          most recent call to [sqlite3_value_blob(V)] or
 **          [sqlite3_value_text(V)].
 **
-** {F15109} The [sqlite3_value_bytes16(V)] interface returns the
+** {H15109} The [sqlite3_value_bytes16(V)] interface returns the
 **          number of bytes in the string (exclusive of the
 **          zero terminator on the string) that was returned by the
 **          most recent call to [sqlite3_value_text16(V)],
 **          [sqlite3_value_text16be(V)], or [sqlite3_value_text16le(V)].
 **
-** {F15112} The [sqlite3_value_double(V)] interface converts the
-**          [sqlite3_value] object V into a floating point value and
+** {H15112} The [sqlite3_value_double(V)] interface converts the
+**          [protected sqlite3_value] object V into a floating point value and
 **          returns a copy of that value.
 **
-** {F15115} The [sqlite3_value_int(V)] interface converts the
-**          [sqlite3_value] object V into a 64-bit signed integer and
+** {H15115} The [sqlite3_value_int(V)] interface converts the
+**          [protected sqlite3_value] object V into a 64-bit signed integer and
 **          returns the lower 32 bits of that integer.
 **
-** {F15118} The [sqlite3_value_int64(V)] interface converts the
-**          [sqlite3_value] object V into a 64-bit signed integer and
+** {H15118} The [sqlite3_value_int64(V)] interface converts the
+**          [protected sqlite3_value] object V into a 64-bit signed integer and
 **          returns a copy of that integer.
 **
-** {F15121} The [sqlite3_value_text(V)] interface converts the
-**          [sqlite3_value] object V into a zero-terminated UTF-8 
+** {H15121} The [sqlite3_value_text(V)] interface converts the
+**          [protected sqlite3_value] object V into a zero-terminated UTF-8
 **          string and returns a pointer to that string.
 **
-** {F15124} The [sqlite3_value_text16(V)] interface converts the
-**          [sqlite3_value] object V into a zero-terminated 2-byte
+** {H15124} The [sqlite3_value_text16(V)] interface converts the
+**          [protected sqlite3_value] object V into a zero-terminated 2-byte
 **          aligned UTF-16 native byte order
 **          string and returns a pointer to that string.
 **
-** {F15127} The [sqlite3_value_text16be(V)] interface converts the
-**          [sqlite3_value] object V into a zero-terminated 2-byte
+** {H15127} The [sqlite3_value_text16be(V)] interface converts the
+**          [protected sqlite3_value] object V into a zero-terminated 2-byte
 **          aligned UTF-16 big-endian
 **          string and returns a pointer to that string.
 **
-** {F15130} The [sqlite3_value_text16le(V)] interface converts the
-**          [sqlite3_value] object V into a zero-terminated 2-byte
+** {H15130} The [sqlite3_value_text16le(V)] interface converts the
+**          [protected sqlite3_value] object V into a zero-terminated 2-byte
 **          aligned UTF-16 little-endian
 **          string and returns a pointer to that string.
 **
-** {F15133} The [sqlite3_value_type(V)] interface returns
+** {H15133} The [sqlite3_value_type(V)] interface returns
 **          one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT],
 **          [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for
 **          the [sqlite3_value] object V.
 **
-** {F15136} The [sqlite3_value_numeric_type(V)] interface converts
-**          the [sqlite3_value] object V into either an integer or
+** {H15136} The [sqlite3_value_numeric_type(V)] interface converts
+**          the [protected sqlite3_value] object V into either an integer or
 **          a floating point value if it can do so without loss of
 **          information, and returns one of [SQLITE_NULL],
 **          [SQLITE_INTEGER], [SQLITE_FLOAT], [SQLITE_TEXT], or
-**          [SQLITE_BLOB] as appropriate for
-**          the [sqlite3_value] object V after the conversion attempt.
+**          [SQLITE_BLOB] as appropriate for the
+**          [protected sqlite3_value] object V after the conversion attempt.
 */
 SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
 SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
@@ -3980,46 +4712,44 @@ SQLITE_API int sqlite3_value_type(sqlite3_value*);
 SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
 
 /*
-** CAPI3REF: Obtain Aggregate Function Context {F16210}
+** CAPI3REF: Obtain Aggregate Function Context {H16210} 
 **
 ** The implementation of aggregate SQL functions use this routine to allocate
-** a structure for storing their state.  
-** The first time the sqlite3_aggregate_context() routine is
-** is called for a particular aggregate, SQLite allocates nBytes of memory
-** zeros that memory, and returns a pointer to it.
-** On second and subsequent calls to sqlite3_aggregate_context()
-** for the same aggregate function index, the same buffer is returned.
-** The implementation
-** of the aggregate can use the returned buffer to accumulate data.
+** a structure for storing their state.
+**
+** The first time the sqlite3_aggregate_context() routine is called for a
+** particular aggregate, SQLite allocates nBytes of memory, zeroes out that
+** memory, and returns a pointer to it. On second and subsequent calls to
+** sqlite3_aggregate_context() for the same aggregate function index,
+** the same buffer is returned. The implementation of the aggregate can use
+** the returned buffer to accumulate data.
 **
 ** SQLite automatically frees the allocated buffer when the aggregate
 ** query concludes.
 **
-** The first parameter should be a copy of the 
-** [sqlite3_context | SQL function context] that is the first
-** parameter to the callback routine that implements the aggregate
-** function.
+** The first parameter should be a copy of the
+** [sqlite3_context | SQL function context] that is the first parameter
+** to the callback routine that implements the aggregate function.
 **
 ** This routine must be called from the same thread in which
 ** the aggregate SQL function is running.
 **
 ** INVARIANTS:
 **
-** {F16211} The first invocation of [sqlite3_aggregate_context(C,N)] for
+** {H16211} The first invocation of [sqlite3_aggregate_context(C,N)] for
 **          a particular instance of an aggregate function (for a particular
-**          context C) causes SQLite to allocation N bytes of memory,
-**          zero that memory, and return a pointer to the allocationed
-**          memory.
+**          context C) causes SQLite to allocate N bytes of memory,
+**          zero that memory, and return a pointer to the allocated memory.
 **
-** {F16213} If a memory allocation error occurs during
+** {H16213} If a memory allocation error occurs during
 **          [sqlite3_aggregate_context(C,N)] then the function returns 0.
 **
-** {F16215} Second and subsequent invocations of
+** {H16215} Second and subsequent invocations of
 **          [sqlite3_aggregate_context(C,N)] for the same context pointer C
 **          ignore the N parameter and return a pointer to the same
 **          block of memory returned by the first invocation.
 **
-** {F16217} The memory allocated by [sqlite3_aggregate_context(C,N)] is
+** {H16217} The memory allocated by [sqlite3_aggregate_context(C,N)] is
 **          automatically freed on the next call to [sqlite3_reset()]
 **          or [sqlite3_finalize()] for the [prepared statement] containing
 **          the aggregate function associated with context C.
@@ -4027,11 +4757,11 @@ SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
 SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
 
 /*
-** CAPI3REF: User Data For Functions {F16240}
+** CAPI3REF: User Data For Functions {H16240} 
 **
 ** The sqlite3_user_data() interface returns a copy of
 ** the pointer that was the pUserData parameter (the 5th parameter)
-** of the the [sqlite3_create_function()]
+** of the [sqlite3_create_function()]
 ** and [sqlite3_create_function16()] routines that originally
 ** registered the application defined function. {END}
 **
@@ -4040,52 +4770,67 @@ SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
 **
 ** INVARIANTS:
 **
-** {F16243} The [sqlite3_user_data(C)] interface returns a copy of the
+** {H16243} The [sqlite3_user_data(C)] interface returns a copy of the
 **          P pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)]
 **          or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that
-**          registered the SQL function associated with 
-**          [sqlite3_context] C.
+**          registered the SQL function associated with [sqlite3_context] C.
 */
 SQLITE_API void *sqlite3_user_data(sqlite3_context*);
 
 /*
-** CAPI3REF: Function Auxiliary Data {F16270}
+** CAPI3REF: Database Connection For Functions {H16250} 
+**
+** The sqlite3_context_db_handle() interface returns a copy of
+** the pointer to the [database connection] (the 1st parameter)
+** of the [sqlite3_create_function()]
+** and [sqlite3_create_function16()] routines that originally
+** registered the application defined function.
+**
+** INVARIANTS:
+**
+** {H16253} The [sqlite3_context_db_handle(C)] interface returns a copy of the
+**          D pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)]
+**          or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that
+**          registered the SQL function associated with [sqlite3_context] C.
+*/
+SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
+
+/*
+** CAPI3REF: Function Auxiliary Data {H16270} 
 **
 ** The following two functions may be used by scalar SQL functions to
-** associate meta-data with argument values. If the same value is passed to
+** associate metadata with argument values. If the same value is passed to
 ** multiple invocations of the same SQL function during query execution, under
-** some circumstances the associated meta-data may be preserved. This may
+** some circumstances the associated metadata may be preserved. This may
 ** be used, for example, to add a regular-expression matching scalar
 ** function. The compiled version of the regular expression is stored as
-** meta-data associated with the SQL value passed as the regular expression
+** metadata associated with the SQL value passed as the regular expression
 ** pattern.  The compiled regular expression can be reused on multiple
 ** invocations of the same function so that the original pattern string
 ** does not need to be recompiled on each invocation.
 **
-** The sqlite3_get_auxdata() interface returns a pointer to the meta-data
+** The sqlite3_get_auxdata() interface returns a pointer to the metadata
 ** associated by the sqlite3_set_auxdata() function with the Nth argument
-** value to the application-defined function.
-** If no meta-data has been ever been set for the Nth
-** argument of the function, or if the cooresponding function parameter
-** has changed since the meta-data was set, then sqlite3_get_auxdata()
-** returns a NULL pointer.
-**
-** The sqlite3_set_auxdata() interface saves the meta-data
-** pointed to by its 3rd parameter as the meta-data for the N-th
+** value to the application-defined function. If no metadata has been ever
+** been set for the Nth argument of the function, or if the corresponding
+** function parameter has changed since the meta-data was set,
+** then sqlite3_get_auxdata() returns a NULL pointer.
+**
+** The sqlite3_set_auxdata() interface saves the metadata
+** pointed to by its 3rd parameter as the metadata for the N-th
 ** argument of the application-defined function.  Subsequent
 ** calls to sqlite3_get_auxdata() might return this data, if it has
-** not been destroyed. 
-** If it is not NULL, SQLite will invoke the destructor 
+** not been destroyed.
+** If it is not NULL, SQLite will invoke the destructor
 ** function given by the 4th parameter to sqlite3_set_auxdata() on
-** the meta-data when the corresponding function parameter changes
+** the metadata when the corresponding function parameter changes
 ** or when the SQL statement completes, whichever comes first.
 **
-** SQLite is free to call the destructor and drop meta-data on
-** any parameter of any function at any time.  The only guarantee
-** is that the destructor will be called before the metadata is
-** dropped.
+** SQLite is free to call the destructor and drop metadata on any
+** parameter of any function at any time.  The only guarantee is that
+** the destructor will be called before the metadata is dropped.
 **
-** In practice, meta-data is preserved between function calls for
+** In practice, metadata is preserved between function calls for
 ** expressions that are constant at compile time. This includes literal
 ** values and SQL variables.
 **
@@ -4094,28 +4839,27 @@ SQLITE_API void *sqlite3_user_data(sqlite3_context*);
 **
 ** INVARIANTS:
 **
-** {F16272} The [sqlite3_get_auxdata(C,N)] interface returns a pointer
+** {H16272} The [sqlite3_get_auxdata(C,N)] interface returns a pointer
 **          to metadata associated with the Nth parameter of the SQL function
 **          whose context is C, or NULL if there is no metadata associated
 **          with that parameter.
 **
-** {F16274} The [sqlite3_set_auxdata(C,N,P,D)] interface assigns a metadata
-**          pointer P to the Nth parameter of the SQL function with context
-**          C.
+** {H16274} The [sqlite3_set_auxdata(C,N,P,D)] interface assigns a metadata
+**          pointer P to the Nth parameter of the SQL function with context C.
 **
-** {F16276} SQLite will invoke the destructor D with a single argument
+** {H16276} SQLite will invoke the destructor D with a single argument
 **          which is the metadata pointer P following a call to
 **          [sqlite3_set_auxdata(C,N,P,D)] when SQLite ceases to hold
 **          the metadata.
 **
-** {F16277} SQLite ceases to hold metadata for an SQL function parameter
+** {H16277} SQLite ceases to hold metadata for an SQL function parameter
 **          when the value of that parameter changes.
 **
-** {F16278} When [sqlite3_set_auxdata(C,N,P,D)] is invoked, the destructor
+** {H16278} When [sqlite3_set_auxdata(C,N,P,D)] is invoked, the destructor
 **          is called for any prior metadata associated with the same function
 **          context C and parameter N.
 **
-** {F16279} SQLite will call destructors for any metadata it is holding
+** {H16279} SQLite will call destructors for any metadata it is holding
 **          in a particular [prepared statement] S when either
 **          [sqlite3_reset(S)] or [sqlite3_finalize(S)] is called.
 */
@@ -4124,12 +4868,12 @@ SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(voi
 
 
 /*
-** CAPI3REF: Constants Defining Special Destructor Behavior {F10280}
+** CAPI3REF: Constants Defining Special Destructor Behavior {H10280} 
 **
-** These are special value for the destructor that is passed in as the
+** These are special values for the destructor that is passed in as the
 ** final argument to routines like [sqlite3_result_blob()].  If the destructor
 ** argument is SQLITE_STATIC, it means that the content pointer is constant
-** and will never change.  It does not need to be destroyed.  The 
+** and will never change.  It does not need to be destroyed.  The
 ** SQLITE_TRANSIENT value means that the content will likely change in
 ** the near future and that SQLite should make its own private copy of
 ** the content before returning.
@@ -4142,30 +4886,28 @@ typedef void (*sqlite3_destructor_type)(void*);
 #define SQLITE_TRANSIENT   ((sqlite3_destructor_type)-1)
 
 /*
-** CAPI3REF: Setting The Result Of An SQL Function {F16400}
+** CAPI3REF: Setting The Result Of An SQL Function {H16400} 
 **
 ** These routines are used by the xFunc or xFinal callbacks that
 ** implement SQL functions and aggregates.  See
 ** [sqlite3_create_function()] and [sqlite3_create_function16()]
 ** for additional information.
 **
-** These functions work very much like the 
-** [sqlite3_bind_blob | sqlite3_bind_*] family of functions used
-** to bind values to host parameters in prepared statements.
-** Refer to the
-** [sqlite3_bind_blob | sqlite3_bind_* documentation] for
-** additional information.
+** These functions work very much like the [parameter binding] family of
+** functions used to bind values to host parameters in prepared statements.
+** Refer to the [SQL parameter] documentation for additional information.
 **
 ** The sqlite3_result_blob() interface sets the result from
-** an application defined function to be the BLOB whose content is pointed
+** an application-defined function to be the BLOB whose content is pointed
 ** to by the second parameter and which is N bytes long where N is the
-** third parameter. 
-** The sqlite3_result_zeroblob() inerfaces set the result of
-** the application defined function to be a BLOB containing all zero
+** third parameter.
+**
+** The sqlite3_result_zeroblob() interfaces set the result of
+** the application-defined function to be a BLOB containing all zero
 ** bytes and N bytes in size, where N is the value of the 2nd parameter.
 **
 ** The sqlite3_result_double() interface sets the result from
-** an application defined function to be a floating point value specified
+** an application-defined function to be a floating point value specified
 ** by its 2nd argument.
 **
 ** The sqlite3_result_error() and sqlite3_result_error16() functions
@@ -4173,8 +4915,8 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** SQLite uses the string pointed to by the
 ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
 ** as the text of an error message.  SQLite interprets the error
-** message string from sqlite3_result_error() as UTF8. SQLite
-** interprets the string from sqlite3_result_error16() as UTF16 in native
+** message string from sqlite3_result_error() as UTF-8. SQLite
+** interprets the string from sqlite3_result_error16() as UTF-16 in native
 ** byte order.  If the third parameter to sqlite3_result_error()
 ** or sqlite3_result_error16() is negative then SQLite takes as the error
 ** message all text up through the first zero character.
@@ -4182,18 +4924,19 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** sqlite3_result_error16() is non-negative then SQLite takes that many
 ** bytes (not characters) from the 2nd parameter as the error message.
 ** The sqlite3_result_error() and sqlite3_result_error16()
-** routines make a copy private copy of the error message text before
+** routines make a private copy of the error message text before
 ** they return.  Hence, the calling function can deallocate or
 ** modify the text after they return without harm.
 ** The sqlite3_result_error_code() function changes the error code
 ** returned by SQLite as a result of an error in a function.  By default,
-** the error code is SQLITE_ERROR. 
+** the error code is SQLITE_ERROR.  A subsequent call to sqlite3_result_error()
+** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
 **
-** The sqlite3_result_toobig() interface causes SQLite
-** to throw an error indicating that a string or BLOB is to long
-** to represent.  The sqlite3_result_nomem() interface
-** causes SQLite to throw an exception indicating that the a
-** memory allocation failed.
+** The sqlite3_result_toobig() interface causes SQLite to throw an error
+** indicating that a string or BLOB is to long to represent.
+**
+** The sqlite3_result_nomem() interface causes SQLite to throw an error
+** indicating that a memory allocation failed.
 **
 ** The sqlite3_result_int() interface sets the return value
 ** of the application-defined function to be the 32-bit signed integer
@@ -4205,7 +4948,7 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** The sqlite3_result_null() interface sets the return value
 ** of the application-defined function to be NULL.
 **
-** The sqlite3_result_text(), sqlite3_result_text16(), 
+** The sqlite3_result_text(), sqlite3_result_text16(),
 ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
 ** set the return value of the application-defined function to be
 ** a text string which is represented as UTF-8, UTF-16 native byte order,
@@ -4213,7 +4956,7 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** SQLite takes the text result from the application from
 ** the 2nd parameter of the sqlite3_result_text* interfaces.
 ** If the 3rd parameter to the sqlite3_result_text* interfaces
-** is negative, then SQLite takes result text from the 2nd parameter 
+** is negative, then SQLite takes result text from the 2nd parameter
 ** through the first zero character.
 ** If the 3rd parameter to the sqlite3_result_text* interfaces
 ** is non-negative, then as many bytes (not characters) of the text
@@ -4221,121 +4964,124 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** function result.
 ** If the 4th parameter to the sqlite3_result_text* interfaces
 ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
-** function as the destructor on the text or blob result when it has
-** finished using that result.
-** If the 4th parameter to the sqlite3_result_text* interfaces
-** or sqlite3_result_blob is the special constant SQLITE_STATIC, then
-** SQLite assumes that the text or blob result is constant space and
-** does not copy the space or call a destructor when it has
+** function as the destructor on the text or BLOB result when it has
 ** finished using that result.
+** If the 4th parameter to the sqlite3_result_text* interfaces or
+** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
+** assumes that the text or BLOB result is in constant space and does not
+** copy the it or call a destructor when it has finished using that result.
 ** If the 4th parameter to the sqlite3_result_text* interfaces
 ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
 ** then SQLite makes a copy of the result into space obtained from
 ** from [sqlite3_malloc()] before it returns.
 **
 ** The sqlite3_result_value() interface sets the result of
-** the application-defined function to be a copy the [sqlite3_value]
-** object specified by the 2nd parameter.  The
+** the application-defined function to be a copy the
+** [unprotected sqlite3_value] object specified by the 2nd parameter.  The
 ** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
-** so that [sqlite3_value] specified in the parameter may change or
+** so that the [sqlite3_value] specified in the parameter may change or
 ** be deallocated after sqlite3_result_value() returns without harm.
+** A [protected sqlite3_value] object may always be used where an
+** [unprotected sqlite3_value] object is required, so either
+** kind of [sqlite3_value] object can be used with this interface.
 **
-** If these routines are called from within the different thread 
-** than the one containing the application-defined function that recieved
+** If these routines are called from within the different thread
+** than the one containing the application-defined function that received
 ** the [sqlite3_context] pointer, the results are undefined.
 **
 ** INVARIANTS:
 **
-** {F16403} The default return value from any SQL function is NULL.
+** {H16403} The default return value from any SQL function is NULL.
 **
-** {F16406} The [sqlite3_result_blob(C,V,N,D)] interface changes the
-**          return value of function C to be a blob that is N bytes
+** {H16406} The [sqlite3_result_blob(C,V,N,D)] interface changes the
+**          return value of function C to be a BLOB that is N bytes
 **          in length and with content pointed to by V.
 **
-** {F16409} The [sqlite3_result_double(C,V)] interface changes the
+** {H16409} The [sqlite3_result_double(C,V)] interface changes the
 **          return value of function C to be the floating point value V.
 **
-** {F16412} The [sqlite3_result_error(C,V,N)] interface changes the return
+** {H16412} The [sqlite3_result_error(C,V,N)] interface changes the return
 **          value of function C to be an exception with error code
-**          [SQLITE_ERROR] and a UTF8 error message copied from V up to the
+**          [SQLITE_ERROR] and a UTF-8 error message copied from V up to the
 **          first zero byte or until N bytes are read if N is positive.
 **
-** {F16415} The [sqlite3_result_error16(C,V,N)] interface changes the return
+** {H16415} The [sqlite3_result_error16(C,V,N)] interface changes the return
 **          value of function C to be an exception with error code
-**          [SQLITE_ERROR] and a UTF16 native byte order error message
+**          [SQLITE_ERROR] and a UTF-16 native byte order error message
 **          copied from V up to the first zero terminator or until N bytes
 **          are read if N is positive.
 **
-** {F16418} The [sqlite3_result_error_toobig(C)] interface changes the return
+** {H16418} The [sqlite3_result_error_toobig(C)] interface changes the return
 **          value of the function C to be an exception with error code
 **          [SQLITE_TOOBIG] and an appropriate error message.
 **
-** {F16421} The [sqlite3_result_error_nomem(C)] interface changes the return
+** {H16421} The [sqlite3_result_error_nomem(C)] interface changes the return
 **          value of the function C to be an exception with error code
 **          [SQLITE_NOMEM] and an appropriate error message.
 **
-** {F16424} The [sqlite3_result_error_code(C,E)] interface changes the return
+** {H16424} The [sqlite3_result_error_code(C,E)] interface changes the return
 **          value of the function C to be an exception with error code E.
 **          The error message text is unchanged.
 **
-** {F16427} The [sqlite3_result_int(C,V)] interface changes the
+** {H16427} The [sqlite3_result_int(C,V)] interface changes the
 **          return value of function C to be the 32-bit integer value V.
 **
-** {F16430} The [sqlite3_result_int64(C,V)] interface changes the
+** {H16430} The [sqlite3_result_int64(C,V)] interface changes the
 **          return value of function C to be the 64-bit integer value V.
 **
-** {F16433} The [sqlite3_result_null(C)] interface changes the
+** {H16433} The [sqlite3_result_null(C)] interface changes the
 **          return value of function C to be NULL.
 **
-** {F16436} The [sqlite3_result_text(C,V,N,D)] interface changes the
-**          return value of function C to be the UTF8 string
-**          V up through the first zero or until N bytes are read if N
-**          is positive.
+** {H16436} The [sqlite3_result_text(C,V,N,D)] interface changes the
+**          return value of function C to be the UTF-8 string
+**          V up to the first zero if N is negative
+**          or the first N bytes of V if N is non-negative.
 **
-** {F16439} The [sqlite3_result_text16(C,V,N,D)] interface changes the
-**          return value of function C to be the UTF16 native byte order
-**          string  V up through the first zero or until N bytes are read if N
-**          is positive.
+** {H16439} The [sqlite3_result_text16(C,V,N,D)] interface changes the
+**          return value of function C to be the UTF-16 native byte order
+**          string V up to the first zero if N is negative
+**          or the first N bytes of V if N is non-negative.
 **
-** {F16442} The [sqlite3_result_text16be(C,V,N,D)] interface changes the
-**          return value of function C to be the UTF16 big-endian
-**          string  V up through the first zero or until N bytes are read if N
-**          is positive.
+** {H16442} The [sqlite3_result_text16be(C,V,N,D)] interface changes the
+**          return value of function C to be the UTF-16 big-endian
+**          string V up to the first zero if N is negative
+**          or the first N bytes or V if N is non-negative.
 **
-** {F16445} The [sqlite3_result_text16le(C,V,N,D)] interface changes the
-**          return value of function C to be the UTF16 little-endian
-**          string  V up through the first zero or until N bytes are read if N
-**          is positive.
+** {H16445} The [sqlite3_result_text16le(C,V,N,D)] interface changes the
+**          return value of function C to be the UTF-16 little-endian
+**          string V up to the first zero if N is negative
+**          or the first N bytes of V if N is non-negative.
 **
-** {F16448} The [sqlite3_result_value(C,V)] interface changes the
-**          return value of function C to be [sqlite3_value] object V.
+** {H16448} The [sqlite3_result_value(C,V)] interface changes the
+**          return value of function C to be the [unprotected sqlite3_value]
+**          object V.
 **
-** {F16451} The [sqlite3_result_zeroblob(C,N)] interface changes the
-**          return value of function C to be an N-byte blob of all zeros.
+** {H16451} The [sqlite3_result_zeroblob(C,N)] interface changes the
+**          return value of function C to be an N-byte BLOB of all zeros.
 **
-** {F16454} The [sqlite3_result_error()] and [sqlite3_result_error16()]
+** {H16454} The [sqlite3_result_error()] and [sqlite3_result_error16()]
 **          interfaces make a copy of their error message strings before
 **          returning.
 **
-** {F16457} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
+** {H16457} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
 **          [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
 **          [sqlite3_result_text16be(C,V,N,D)], or
 **          [sqlite3_result_text16le(C,V,N,D)] is the constant [SQLITE_STATIC]
 **          then no destructor is ever called on the pointer V and SQLite
 **          assumes that V is immutable.
 **
-** {F16460} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
+** {H16460} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
 **          [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
 **          [sqlite3_result_text16be(C,V,N,D)], or
 **          [sqlite3_result_text16le(C,V,N,D)] is the constant
 **          [SQLITE_TRANSIENT] then the interfaces makes a copy of the
 **          content of V and retains the copy.
 **
-** {F16463} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
+** {H16463} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
 **          [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
 **          [sqlite3_result_text16be(C,V,N,D)], or
 **          [sqlite3_result_text16le(C,V,N,D)] is some value other than
-**          the constants [SQLITE_STATIC] and [SQLITE_TRANSIENT] then 
+**          the constants [SQLITE_STATIC] and [SQLITE_TRANSIENT] then
 **          SQLite will invoke the destructor D with V as its only argument
 **          when it has finished with the V value.
 */
@@ -4357,10 +5103,10 @@ SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
 SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
 
 /*
-** CAPI3REF: Define New Collating Sequences {F16600}
+** CAPI3REF: Define New Collating Sequences {H16600} 
 **
 ** These functions are used to add new collation sequences to the
-** [sqlite3*] handle specified as the first argument. 
+** [database connection] specified as the first argument.
 **
 ** The name of the new collation sequence is specified as a UTF-8 string
 ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
@@ -4370,81 +5116,79 @@ SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
 ** The third argument may be one of the constants [SQLITE_UTF8],
 ** [SQLITE_UTF16LE] or [SQLITE_UTF16BE], indicating that the user-supplied
 ** routine expects to be passed pointers to strings encoded using UTF-8,
-** UTF-16 little-endian or UTF-16 big-endian respectively. The
+** UTF-16 little-endian, or UTF-16 big-endian, respectively. The
 ** third argument might also be [SQLITE_UTF16_ALIGNED] to indicate that
 ** the routine expects pointers to 16-bit word aligned strings
-** of UTF16 in the native byte order of the host computer.
+** of UTF-16 in the native byte order of the host computer.
 **
 ** A pointer to the user supplied routine must be passed as the fifth
 ** argument.  If it is NULL, this is the same as deleting the collation
 ** sequence (so that SQLite cannot call it anymore).
-** Each time the application
-** supplied function is invoked, it is passed a copy of the void* passed as
-** the fourth argument to sqlite3_create_collation() or
-** sqlite3_create_collation16() as its first parameter.
+** Each time the application supplied function is invoked, it is passed
+** as its first parameter a copy of the void* passed as the fourth argument
+** to sqlite3_create_collation() or sqlite3_create_collation16().
 **
 ** The remaining arguments to the application-supplied routine are two strings,
 ** each represented by a (length, data) pair and encoded in the encoding
 ** that was passed as the third argument when the collation sequence was
-** registered. {END} The application defined collation routine should
-** return negative, zero or positive if
-** the first string is less than, equal to, or greater than the second
-** string. i.e. (STRING1 - STRING2).
+** registered. {END}  The application defined collation routine should
+** return negative, zero or positive if the first string is less than,
+** equal to, or greater than the second string. i.e. (STRING1 - STRING2).
 **
 ** The sqlite3_create_collation_v2() works like sqlite3_create_collation()
-** excapt that it takes an extra argument which is a destructor for
+** except that it takes an extra argument which is a destructor for
 ** the collation.  The destructor is called when the collation is
 ** destroyed and is passed a copy of the fourth parameter void* pointer
 ** of the sqlite3_create_collation_v2().
-** Collations are destroyed when
-** they are overridden by later calls to the collation creation functions
-** or when the [sqlite3*] database handle is closed using [sqlite3_close()].
+** Collations are destroyed when they are overridden by later calls to the
+** collation creation functions or when the [database connection] is closed
+** using [sqlite3_close()].
 **
 ** INVARIANTS:
 **
-** {F16603} A successful call to the
+** {H16603} A successful call to the
 **          [sqlite3_create_collation_v2(B,X,E,P,F,D)] interface
 **          registers function F as the comparison function used to
-**          implement collation X on [database connection] B for
+**          implement collation X on the [database connection] B for
 **          databases having encoding E.
 **
-** {F16604} SQLite understands the X parameter to
+** {H16604} SQLite understands the X parameter to
 **          [sqlite3_create_collation_v2(B,X,E,P,F,D)] as a zero-terminated
 **          UTF-8 string in which case is ignored for ASCII characters and
 **          is significant for non-ASCII characters.
 **
-** {F16606} Successive calls to [sqlite3_create_collation_v2(B,X,E,P,F,D)]
+** {H16606} Successive calls to [sqlite3_create_collation_v2(B,X,E,P,F,D)]
 **          with the same values for B, X, and E, override prior values
 **          of P, F, and D.
 **
-** {F16609} The destructor D in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
+** {H16609} If the destructor D in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
 **          is not NULL then it is called with argument P when the
 **          collating function is dropped by SQLite.
 **
-** {F16612} A collating function is dropped when it is overloaded.
+** {H16612} A collating function is dropped when it is overloaded.
 **
-** {F16615} A collating function is dropped when the database connection
+** {H16615} A collating function is dropped when the database connection
 **          is closed using [sqlite3_close()].
 **
-** {F16618} The pointer P in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
+** {H16618} The pointer P in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
 **          is passed through as the first parameter to the comparison
 **          function F for all subsequent invocations of F.
 **
-** {F16621} A call to [sqlite3_create_collation(B,X,E,P,F)] is exactly
+** {H16621} A call to [sqlite3_create_collation(B,X,E,P,F)] is exactly
 **          the same as a call to [sqlite3_create_collation_v2()] with
 **          the same parameters and a NULL destructor.
 **
-** {F16624} Following a [sqlite3_create_collation_v2(B,X,E,P,F,D)],
+** {H16624} Following a [sqlite3_create_collation_v2(B,X,E,P,F,D)],
 **          SQLite uses the comparison function F for all text comparison
-**          operations on [database connection] B on text values that
-**          use the collating sequence name X.
+**          operations on the [database connection] B on text values that
+**          use the collating sequence named X.
 **
-** {F16627} The [sqlite3_create_collation16(B,X,E,P,F)] works the same
+** {H16627} The [sqlite3_create_collation16(B,X,E,P,F)] works the same
 **          as [sqlite3_create_collation(B,X,E,P,F)] except that the
 **          collation name X is understood as UTF-16 in native byte order
 **          instead of UTF-8.
 **
-** {F16630} When multiple comparison functions are available for the same
+** {H16630} When multiple comparison functions are available for the same
 **          collating sequence, SQLite chooses the one whose text encoding
 **          requires the least amount of conversion from the default
 **          text encoding of the database.
@@ -4466,33 +5210,32 @@ SQLITE_API int sqlite3_create_collation_v2(
 );
 SQLITE_API int sqlite3_create_collation16(
   sqlite3*, 
-  const char *zName, 
+  const void *zName,
   int eTextRep, 
   void*,
   int(*xCompare)(void*,int,const void*,int,const void*)
 );
 
 /*
-** CAPI3REF: Collation Needed Callbacks {F16700}
+** CAPI3REF: Collation Needed Callbacks {H16700} 
 **
 ** To avoid having to register all collation sequences before a database
 ** can be used, a single callback function may be registered with the
-** database handle to be called whenever an undefined collation sequence is
-** required.
+** [database connection] to be called whenever an undefined collation
+** sequence is required.
 **
 ** If the function is registered using the sqlite3_collation_needed() API,
 ** then it is passed the names of undefined collation sequences as strings
-** encoded in UTF-8. {F16703} If sqlite3_collation_needed16() is used, the names
-** are passed as UTF-16 in machine native byte order. A call to either
-** function replaces any existing callback.
+** encoded in UTF-8. {H16703} If sqlite3_collation_needed16() is used,
+** the names are passed as UTF-16 in machine native byte order.
+** A call to either function replaces any existing callback.
 **
 ** When the callback is invoked, the first argument passed is a copy
 ** of the second argument to sqlite3_collation_needed() or
 ** sqlite3_collation_needed16().  The second argument is the database
-** handle.  The third argument is one of [SQLITE_UTF8],
-** [SQLITE_UTF16BE], or [SQLITE_UTF16LE], indicating the most
-** desirable form of the collation sequence function required.
-** The fourth parameter is the name of the
+** connection.  The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
+** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
+** sequence function required.  The fourth parameter is the name of the
 ** required collation sequence.
 **
 ** The callback function should register the desired collation using
@@ -4501,24 +5244,22 @@ SQLITE_API int sqlite3_create_collation16(
 **
 ** INVARIANTS:
 **
-** {F16702} A successful call to [sqlite3_collation_needed(D,P,F)]
+** {H16702} A successful call to [sqlite3_collation_needed(D,P,F)]
 **          or [sqlite3_collation_needed16(D,P,F)] causes
 **          the [database connection] D to invoke callback F with first
 **          parameter P whenever it needs a comparison function for a
 **          collating sequence that it does not know about.
 **
-** {F16704} Each successful call to [sqlite3_collation_needed()] or
+** {H16704} Each successful call to [sqlite3_collation_needed()] or
 **          [sqlite3_collation_needed16()] overrides the callback registered
 **          on the same [database connection] by prior calls to either
 **          interface.
 **
-** {F16706} The name of the requested collating function passed in the
+** {H16706} The name of the requested collating function passed in the
 **          4th parameter to the callback is in UTF-8 if the callback
 **          was registered using [sqlite3_collation_needed()] and
 **          is in UTF-16 native byte order if the callback was
 **          registered using [sqlite3_collation_needed16()].
-**
-** 
 */
 SQLITE_API int sqlite3_collation_needed(
   sqlite3*, 
@@ -4557,15 +5298,14 @@ SQLITE_API int sqlite3_rekey(
 );
 
 /*
-** CAPI3REF:  Suspend Execution For A Short Time {F10530}
+** CAPI3REF: Suspend Execution For A Short Time {H10530} 
 **
-** The sqlite3_sleep() function
-** causes the current thread to suspend execution
+** The sqlite3_sleep() function causes the current thread to suspend execution
 ** for at least a number of milliseconds specified in its parameter.
 **
-** If the operating system does not support sleep requests with 
-** millisecond time resolution, then the time will be rounded up to 
-** the nearest second. The number of milliseconds of sleep actually 
+** If the operating system does not support sleep requests with
+** millisecond time resolution, then the time will be rounded up to
+** the nearest second. The number of milliseconds of sleep actually
 ** requested from the operating system is returned.
 **
 ** SQLite implements this interface by calling the xSleep()
@@ -4573,27 +5313,27 @@ SQLITE_API int sqlite3_rekey(
 **
 ** INVARIANTS:
 **
-** {F10533} The [sqlite3_sleep(M)] interface invokes the xSleep
+** {H10533} The [sqlite3_sleep(M)] interface invokes the xSleep
 **          method of the default [sqlite3_vfs|VFS] in order to
 **          suspend execution of the current thread for at least
 **          M milliseconds.
 **
-** {F10536} The [sqlite3_sleep(M)] interface returns the number of
+** {H10536} The [sqlite3_sleep(M)] interface returns the number of
 **          milliseconds of sleep actually requested of the operating
 **          system, which might be larger than the parameter M.
 */
 SQLITE_API int sqlite3_sleep(int);
 
 /*
-** CAPI3REF:  Name Of The Folder Holding Temporary Files {F10310}
+** CAPI3REF: Name Of The Folder Holding Temporary Files {H10310} 
 **
 ** If this global variable is made to point to a string which is
-** the name of a folder (a.ka. directory), then all temporary files
+** the name of a folder (a.k.a. directory), then all temporary files
 ** created by SQLite will be placed in that directory.  If this variable
-** is NULL pointer, then SQLite does a search for an appropriate temporary
-** file directory.
+** is a NULL pointer, then SQLite performs a search for an appropriate
+** temporary file directory.
 **
-** It is not safe to modify this variable once a database connection
+** It is not safe to modify this variable once a [database connection]
 ** has been opened.  It is intended that this variable be set once
 ** as part of process initialization and before any SQLite interface
 ** routines have been call and remain unchanged thereafter.
@@ -4601,65 +5341,99 @@ SQLITE_API int sqlite3_sleep(int);
 SQLITE_API char *sqlite3_temp_directory;
 
 /*
-** CAPI3REF:  Test To See If The Database Is In Auto-Commit Mode {F12930}
+** CAPI3REF: Test For Auto-Commit Mode {H12930} 
+** KEYWORDS: {autocommit mode}
 **
-** The sqlite3_get_autocommit() interfaces returns non-zero or
+** The sqlite3_get_autocommit() interface returns non-zero or
 ** zero if the given database connection is or is not in autocommit mode,
-** respectively.   Autocommit mode is on
-** by default.  Autocommit mode is disabled by a [BEGIN] statement.
-** Autocommit mode is reenabled by a [COMMIT] or [ROLLBACK].
+** respectively.  Autocommit mode is on by default.
+** Autocommit mode is disabled by a [BEGIN] statement.
+** Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
 **
 ** If certain kinds of errors occur on a statement within a multi-statement
-** transactions (errors including [SQLITE_FULL], [SQLITE_IOERR], 
+** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
 ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
 ** transaction might be rolled back automatically.  The only way to
-** find out if SQLite automatically rolled back the transaction after
+** find out whether SQLite automatically rolled back the transaction after
 ** an error is to use this function.
 **
 ** INVARIANTS:
 **
-** {F12931} The [sqlite3_get_autocommit(D)] interface returns non-zero or
+** {H12931} The [sqlite3_get_autocommit(D)] interface returns non-zero or
 **          zero if the [database connection] D is or is not in autocommit
 **          mode, respectively.
 **
-** {F12932} Autocommit mode is on by default.
+** {H12932} Autocommit mode is on by default.
 **
-** {F12933} Autocommit mode is disabled by a successful [BEGIN] statement.
+** {H12933} Autocommit mode is disabled by a successful [BEGIN] statement.
 **
-** {F12934} Autocommit mode is enabled by a successful [COMMIT] or [ROLLBACK]
+** {H12934} Autocommit mode is enabled by a successful [COMMIT] or [ROLLBACK]
 **          statement.
-** 
 **
-** LIMITATIONS:
-***
-** {U12936} If another thread changes the autocommit status of the database
+** ASSUMPTIONS:
+**
+** {A12936} If another thread changes the autocommit status of the database
 **          connection while this routine is running, then the return value
 **          is undefined.
 */
 SQLITE_API int sqlite3_get_autocommit(sqlite3*);
 
 /*
-** CAPI3REF:  Find The Database Handle Of A Prepared Statement {F13120}
+** CAPI3REF: Find The Database Handle Of A Prepared Statement {H13120} 
 **
-** The sqlite3_db_handle interface
-** returns the [sqlite3*] database handle to which a
-** [prepared statement] belongs.
-** The database handle returned by sqlite3_db_handle
-** is the same database handle that was
-** the first argument to the [sqlite3_prepare_v2()] or its variants
-** that was used to create the statement in the first place.
+** The sqlite3_db_handle interface returns the [database connection] handle
+** to which a [prepared statement] belongs.  The database handle returned by
+** sqlite3_db_handle is the same database handle that was the first argument
+** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
+** create the statement in the first place.
 **
 ** INVARIANTS:
 **
-** {F13123} The [sqlite3_db_handle(S)] interface returns a pointer
-**          to the [database connection] associated with
+** {H13123} The [sqlite3_db_handle(S)] interface returns a pointer
+**          to the [database connection] associated with the
 **          [prepared statement] S.
 */
 SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
 
+/*
+** CAPI3REF: Find the next prepared statement {H13140} 
+**
+** This interface returns a pointer to the next [prepared statement] after
+** pStmt associated with the [database connection] pDb.  If pStmt is NULL
+** then this interface returns a pointer to the first prepared statement
+** associated with the database connection pDb.  If no prepared statement
+** satisfies the conditions of this routine, it returns NULL.
+**
+** INVARIANTS:
+**
+** {H13143} If D is a [database connection] that holds one or more
+**          unfinalized [prepared statements] and S is a NULL pointer,
+**          then [sqlite3_next_stmt(D, S)] routine shall return a pointer
+**          to one of the prepared statements associated with D.
+**
+** {H13146} If D is a [database connection] that holds no unfinalized
+**          [prepared statements] and S is a NULL pointer, then
+**          [sqlite3_next_stmt(D, S)] routine shall return a NULL pointer.
+**
+** {H13149} If S is a [prepared statement] in the [database connection] D
+**          and S is not the last prepared statement in D, then
+**          [sqlite3_next_stmt(D, S)] routine shall return a pointer
+**          to the next prepared statement in D after S.
+**
+** {H13152} If S is the last [prepared statement] in the
+**          [database connection] D then the [sqlite3_next_stmt(D, S)]
+**          routine shall return a NULL pointer.
+**
+** ASSUMPTIONS:
+**
+** {A13154} The [database connection] pointer D in a call to
+**          [sqlite3_next_stmt(D,S)] must refer to an open database
+**          connection and in particular must not be a NULL pointer.
+*/
+SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
 
 /*
-** CAPI3REF: Commit And Rollback Notification Callbacks {F12950}
+** CAPI3REF: Commit And Rollback Notification Callbacks {H12950} 
 **
 ** The sqlite3_commit_hook() interface registers a callback
 ** function to be invoked whenever a transaction is committed.
@@ -4669,16 +5443,24 @@ SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
 ** function to be invoked whenever a transaction is committed.
 ** Any callback set by a previous call to sqlite3_commit_hook()
 ** for the same database connection is overridden.
-** The pArg argument is passed through
-** to the callback.  If the callback on a commit hook function 
-** returns non-zero, then the commit is converted into a rollback.
+** The pArg argument is passed through to the callback.
+** If the callback on a commit hook function returns non-zero,
+** then the commit is converted into a rollback.
 **
 ** If another function was previously registered, its
 ** pArg value is returned.  Otherwise NULL is returned.
 **
+** The callback implementation must not do anything that will modify
+** the database connection that invoked the callback.  Any actions
+** to modify the database connection must be deferred until after the
+** completion of the [sqlite3_step()] call that triggered the commit
+** or rollback hook in the first place.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
 ** Registering a NULL function disables the callback.
 **
-** For the purposes of this API, a transaction is said to have been 
+** For the purposes of this API, a transaction is said to have been
 ** rolled back if an explicit "ROLLBACK" statement is executed, or
 ** an error or constraint causes an implicit rollback to occur.
 ** The rollback callback is not invoked if a transaction is
@@ -4687,107 +5469,108 @@ SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
 ** rolled back because a commit callback returned non-zero.
 **  Check on this 
 **
-** These are experimental interfaces and are subject to change.
-**
 ** INVARIANTS:
 **
-** {F12951} The [sqlite3_commit_hook(D,F,P)] interface registers the
+** {H12951} The [sqlite3_commit_hook(D,F,P)] interface registers the
 **          callback function F to be invoked with argument P whenever
-**          a transaction commits on [database connection] D.
+**          a transaction commits on the [database connection] D.
 **
-** {F12952} The [sqlite3_commit_hook(D,F,P)] interface returns the P
-**          argument from the previous call with the same 
-**          [database connection ] D , or NULL on the first call
-**          for a particular [database connection] D.
+** {H12952} The [sqlite3_commit_hook(D,F,P)] interface returns the P argument
+**          from the previous call with the same [database connection] D,
+**          or NULL on the first call for a particular database connection D.
 **
-** {F12953} Each call to [sqlite3_commit_hook()] overwrites the callback
+** {H12953} Each call to [sqlite3_commit_hook()] overwrites the callback
 **          registered by prior calls.
 **
-** {F12954} If the F argument to [sqlite3_commit_hook(D,F,P)] is NULL
-**          then the commit hook callback is cancelled and no callback
+** {H12954} If the F argument to [sqlite3_commit_hook(D,F,P)] is NULL
+**          then the commit hook callback is canceled and no callback
 **          is invoked when a transaction commits.
 **
-** {F12955} If the commit callback returns non-zero then the commit is
+** {H12955} If the commit callback returns non-zero then the commit is
 **          converted into a rollback.
 **
-** {F12961} The [sqlite3_rollback_hook(D,F,P)] interface registers the
+** {H12961} The [sqlite3_rollback_hook(D,F,P)] interface registers the
 **          callback function F to be invoked with argument P whenever
-**          a transaction rolls back on [database connection] D.
+**          a transaction rolls back on the [database connection] D.
 **
-** {F12962} The [sqlite3_rollback_hook(D,F,P)] interface returns the P
-**          argument from the previous call with the same 
-**          [database connection ] D , or NULL on the first call
-**          for a particular [database connection] D.
+** {H12962} The [sqlite3_rollback_hook(D,F,P)] interface returns the P
+**          argument from the previous call with the same
+**          [database connection] D, or NULL on the first call
+**          for a particular database connection D.
 **
-** {F12963} Each call to [sqlite3_rollback_hook()] overwrites the callback
+** {H12963} Each call to [sqlite3_rollback_hook()] overwrites the callback
 **          registered by prior calls.
 **
-** {F12964} If the F argument to [sqlite3_rollback_hook(D,F,P)] is NULL
-**          then the rollback hook callback is cancelled and no callback
+** {H12964} If the F argument to [sqlite3_rollback_hook(D,F,P)] is NULL
+**          then the rollback hook callback is canceled and no callback
 **          is invoked when a transaction rolls back.
 */
 SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
 SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
 
 /*
-** CAPI3REF: Data Change Notification Callbacks {F12970}
-**
-** The sqlite3_update_hook() interface
-** registers a callback function with the database connection identified by the 
-** first argument to be invoked whenever a row is updated, inserted or deleted.
-** Any callback set by a previous call to this function for the same 
-** database connection is overridden.
-**
-** The second argument is a pointer to the function to invoke when a 
-** row is updated, inserted or deleted. 
-** The first argument to the callback is
-** a copy of the third argument to sqlite3_update_hook().
-** The second callback 
-** argument is one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
-** depending on the operation that caused the callback to be invoked.
-** The third and 
-** fourth arguments to the callback contain pointers to the database and 
-** table name containing the affected row.
-** The final callback parameter is 
-** the rowid of the row.
-** In the case of an update, this is the rowid after 
-** the update takes place.
+** CAPI3REF: Data Change Notification Callbacks {H12970} 
+**
+** The sqlite3_update_hook() interface registers a callback function
+** with the [database connection] identified by the first argument
+** to be invoked whenever a row is updated, inserted or deleted.
+** Any callback set by a previous call to this function
+** for the same database connection is overridden.
+**
+** The second argument is a pointer to the function to invoke when a
+** row is updated, inserted or deleted.
+** The first argument to the callback is a copy of the third argument
+** to sqlite3_update_hook().
+** The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
+** or [SQLITE_UPDATE], depending on the operation that caused the callback
+** to be invoked.
+** The third and fourth arguments to the callback contain pointers to the
+** database and table name containing the affected row.
+** The final callback parameter is the rowid of the row. In the case of
+** an update, this is the rowid after the update takes place.
 **
 ** The update hook is not invoked when internal system tables are
 ** modified (i.e. sqlite_master and sqlite_sequence).
 **
+** The update hook implementation must not do anything that will modify
+** the database connection that invoked the update hook.  Any actions
+** to modify the database connection must be deferred until after the
+** completion of the [sqlite3_step()] call that triggered the update hook.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
 ** If another function was previously registered, its pArg value
 ** is returned.  Otherwise NULL is returned.
 **
 ** INVARIANTS:
 **
-** {F12971} The [sqlite3_update_hook(D,F,P)] interface causes callback
+** {H12971} The [sqlite3_update_hook(D,F,P)] interface causes the callback
 **          function F to be invoked with first parameter P whenever
 **          a table row is modified, inserted, or deleted on
-**          [database connection] D.
+**          the [database connection] D.
 **
-** {F12973} The [sqlite3_update_hook(D,F,P)] interface returns the value
+** {H12973} The [sqlite3_update_hook(D,F,P)] interface returns the value
 **          of P for the previous call on the same [database connection] D,
 **          or NULL for the first call.
 **
-** {F12975} If the update hook callback F in [sqlite3_update_hook(D,F,P)]
+** {H12975} If the update hook callback F in [sqlite3_update_hook(D,F,P)]
 **          is NULL then the no update callbacks are made.
 **
-** {F12977} Each call to [sqlite3_update_hook(D,F,P)] overrides prior calls
+** {H12977} Each call to [sqlite3_update_hook(D,F,P)] overrides prior calls
 **          to the same interface on the same [database connection] D.
 **
-** {F12979} The update hook callback is not invoked when internal system
+** {H12979} The update hook callback is not invoked when internal system
 **          tables such as sqlite_master and sqlite_sequence are modified.
 **
-** {F12981} The second parameter to the update callback 
+** {H12981} The second parameter to the update callback
 **          is one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
 **          depending on the operation that caused the callback to be invoked.
 **
-** {F12983} The third and fourth arguments to the callback contain pointers
+** {H12983} The third and fourth arguments to the callback contain pointers
 **          to zero-terminated UTF-8 strings which are the names of the
 **          database and table that is being updated.
 
-** {F12985} The final callback parameter is the rowid of the row after
+** {H12985} The final callback parameter is the rowid of the row after
 **          the change occurs.
 */
 SQLITE_API void *sqlite3_update_hook(
@@ -4797,96 +5580,92 @@ SQLITE_API void *sqlite3_update_hook(
 );
 
 /*
-** CAPI3REF:  Enable Or Disable Shared Pager Cache {F10330}
+** CAPI3REF: Enable Or Disable Shared Pager Cache {H10330} 
+** KEYWORDS: {shared cache} {shared cache mode}
 **
 ** This routine enables or disables the sharing of the database cache
-** and schema data structures between connections to the same database.
-** Sharing is enabled if the argument is true and disabled if the argument
-** is false.
+** and schema data structures between [database connection | connections]
+** to the same database. Sharing is enabled if the argument is true
+** and disabled if the argument is false.
 **
-** Cache sharing is enabled and disabled
-** for an entire process. {END} This is a change as of SQLite version 3.5.0.
-** In prior versions of SQLite, sharing was
-** enabled or disabled for each thread separately.
+** Cache sharing is enabled and disabled for an entire process. {END}
+** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
+** sharing was enabled or disabled for each thread separately.
 **
 ** The cache sharing mode set by this interface effects all subsequent
 ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
 ** Existing database connections continue use the sharing mode
 ** that was in effect at the time they were opened.
 **
-** Virtual tables cannot be used with a shared cache.   When shared
+** Virtual tables cannot be used with a shared cache.  When shared
 ** cache is enabled, the [sqlite3_create_module()] API used to register
 ** virtual tables will always return an error.
 **
-** This routine returns [SQLITE_OK] if shared cache was
-** enabled or disabled successfully.  An [error code]
-** is returned otherwise.
+** This routine returns [SQLITE_OK] if shared cache was enabled or disabled
+** successfully.  An [error code] is returned otherwise.
 **
 ** Shared cache is disabled by default. But this might change in
 ** future releases of SQLite.  Applications that care about shared
 ** cache setting should set it explicitly.
 **
 ** INVARIANTS:
-** 
-** {F10331} A successful invocation of [sqlite3_enable_shared_cache(B)]
+**
+** {H10331} A successful invocation of [sqlite3_enable_shared_cache(B)]
 **          will enable or disable shared cache mode for any subsequently
 **          created [database connection] in the same process.
 **
-** {F10336} When shared cache is enabled, the [sqlite3_create_module()]
+** {H10336} When shared cache is enabled, the [sqlite3_create_module()]
 **          interface will always return an error.
 **
-** {F10337} The [sqlite3_enable_shared_cache(B)] interface returns
+** {H10337} The [sqlite3_enable_shared_cache(B)] interface returns
 **          [SQLITE_OK] if shared cache was enabled or disabled successfully.
 **
-** {F10339} Shared cache is disabled by default.
+** {H10339} Shared cache is disabled by default.
 */
 SQLITE_API int sqlite3_enable_shared_cache(int);
 
 /*
-** CAPI3REF:  Attempt To Free Heap Memory {F17340}
+** CAPI3REF: Attempt To Free Heap Memory {H17340} 
 **
-** The sqlite3_release_memory() interface attempts to
-** free N bytes of heap memory by deallocating non-essential memory
-** allocations held by the database labrary. {END}  Memory used
-** to cache database pages to improve performance is an example of
-** non-essential memory.  Sqlite3_release_memory() returns
-** the number of bytes actually freed, which might be more or less
-** than the amount requested.
+** The sqlite3_release_memory() interface attempts to free N bytes
+** of heap memory by deallocating non-essential memory allocations
+** held by the database library. {END}  Memory used to cache database
+** pages to improve performance is an example of non-essential memory.
+** sqlite3_release_memory() returns the number of bytes actually freed,
+** which might be more or less than the amount requested.
 **
 ** INVARIANTS:
 **
-** {F17341} The [sqlite3_release_memory(N)] interface attempts to
+** {H17341} The [sqlite3_release_memory(N)] interface attempts to
 **          free N bytes of heap memory by deallocating non-essential
-**          memory allocations held by the database labrary.
+**          memory allocations held by the database library.
 **
-** {F16342} The [sqlite3_release_memory(N)] returns the number
+** {H16342} The [sqlite3_release_memory(N)] returns the number
 **          of bytes actually freed, which might be more or less
 **          than the amount requested.
 */
 SQLITE_API int sqlite3_release_memory(int);
 
 /*
-** CAPI3REF:  Impose A Limit On Heap Size {F17350}
+** CAPI3REF: Impose A Limit On Heap Size {H17350} 
 **
-** The sqlite3_soft_heap_limit() interface
-** places a "soft" limit on the amount of heap memory that may be allocated
-** by SQLite. If an internal allocation is requested 
-** that would exceed the soft heap limit, [sqlite3_release_memory()] is
-** invoked one or more times to free up some space before the allocation
-** is made.
+** The sqlite3_soft_heap_limit() interface places a "soft" limit
+** on the amount of heap memory that may be allocated by SQLite.
+** If an internal allocation is requested that would exceed the
+** soft heap limit, [sqlite3_release_memory()] is invoked one or
+** more times to free up some space before the allocation is performed.
 **
-** The limit is called "soft", because if
-** [sqlite3_release_memory()] cannot
-** free sufficient memory to prevent the limit from being exceeded,
+** The limit is called "soft", because if [sqlite3_release_memory()]
+** cannot free sufficient memory to prevent the limit from being exceeded,
 ** the memory is allocated anyway and the current operation proceeds.
 **
 ** A negative or zero value for N means that there is no soft heap limit and
 ** [sqlite3_release_memory()] will only be called when memory is exhausted.
 ** The default value for the soft heap limit is zero.
 **
-** SQLite makes a best effort to honor the soft heap limit.  
-** But if the soft heap limit cannot honored, execution will
-** continue without error or notification.  This is why the limit is 
+** SQLite makes a best effort to honor the soft heap limit.
+** But if the soft heap limit cannot be honored, execution will
+** continue without error or notification.  This is why the limit is
 ** called a "soft" limit.  It is advisory only.
 **
 ** Prior to SQLite version 3.5.0, this routine only constrained the memory
@@ -4899,81 +5678,79 @@ SQLITE_API int sqlite3_release_memory(int);
 **
 ** INVARIANTS:
 **
-** {F16351} The [sqlite3_soft_heap_limit(N)] interface places a soft limit
+** {H16351} The [sqlite3_soft_heap_limit(N)] interface places a soft limit
 **          of N bytes on the amount of heap memory that may be allocated
 **          using [sqlite3_malloc()] or [sqlite3_realloc()] at any point
 **          in time.
 **
-** {F16352} If a call to [sqlite3_malloc()] or [sqlite3_realloc()] would
+** {H16352} If a call to [sqlite3_malloc()] or [sqlite3_realloc()] would
 **          cause the total amount of allocated memory to exceed the
 **          soft heap limit, then [sqlite3_release_memory()] is invoked
 **          in an attempt to reduce the memory usage prior to proceeding
 **          with the memory allocation attempt.
 **
-** {F16353} Calls to [sqlite3_malloc()] or [sqlite3_realloc()] that trigger
+** {H16353} Calls to [sqlite3_malloc()] or [sqlite3_realloc()] that trigger
 **          attempts to reduce memory usage through the soft heap limit
 **          mechanism continue even if the attempt to reduce memory
 **          usage is unsuccessful.
 **
-** {F16354} A negative or zero value for N in a call to
+** {H16354} A negative or zero value for N in a call to
 **          [sqlite3_soft_heap_limit(N)] means that there is no soft
 **          heap limit and [sqlite3_release_memory()] will only be
 **          called when memory is completely exhausted.
 **
-** {F16355} The default value for the soft heap limit is zero.
+** {H16355} The default value for the soft heap limit is zero.
 **
-** {F16358} Each call to [sqlite3_soft_heap_limit(N)] overrides the
+** {H16358} Each call to [sqlite3_soft_heap_limit(N)] overrides the
 **          values set by all prior calls.
 */
 SQLITE_API void sqlite3_soft_heap_limit(int);
 
 /*
-** CAPI3REF:  Extract Metadata About A Column Of A Table {F12850}
+** CAPI3REF: Extract Metadata About A Column Of A Table {H12850} 
 **
-** This routine
-** returns meta-data about a specific column of a specific database
-** table accessible using the connection handle passed as the first function 
-** argument.
+** This routine returns metadata about a specific column of a specific
+** database table accessible using the [database connection] handle
+** passed as the first function argument.
 **
-** The column is identified by the second, third and fourth parameters to 
+** The column is identified by the second, third and fourth parameters to
 ** this function. The second parameter is either the name of the database
 ** (i.e. "main", "temp" or an attached database) containing the specified
 ** table or NULL. If it is NULL, then all attached databases are searched
-** for the table using the same algorithm as the database engine uses to 
+** for the table using the same algorithm used by the database engine to
 ** resolve unqualified table references.
 **
-** The third and fourth parameters to this function are the table and column 
-** name of the desired column, respectively. Neither of these parameters 
+** The third and fourth parameters to this function are the table and column
+** name of the desired column, respectively. Neither of these parameters
 ** may be NULL.
 **
-** Meta information is returned by writing to the memory locations passed as
-** the 5th and subsequent parameters to this function. Any of these 
-** arguments may be NULL, in which case the corresponding element of meta 
-** information is ommitted.
+** Metadata is returned by writing to the memory locations passed as the 5th
+** and subsequent parameters to this function. Any of these arguments may be
+** NULL, in which case the corresponding element of metadata is omitted.
 **
-** 
      -** Parameter     Output Type      Description
-** -----------------------------------
-**
-**   5th         const char*      Data type
-**   6th         const char*      Name of the default collation sequence 
-**   7th         int              True if the column has a NOT NULL constraint
-**   8th         int              True if the column is part of the PRIMARY KEY
-**   9th         int              True if the column is AUTOINCREMENT
-** 
      
+** 
      
+** 
+** 
       Parameter  Output
      Type       		  Description
 **
+** 
       5th  const char*  Data type
+** 
       6th  const char*  Name of default collation sequence
+** 
       7th  int          True if column has a NOT NULL constraint
+** 
       8th  int          True if column is part of the PRIMARY KEY
+** 
       9th  int          True if column is AUTOINCREMENT
+** 
      
+** 
      
 **
-** The memory pointed to by the character pointers returned for the 
-** declaration type and collation sequence is valid only until the next 
-** call to any sqlite API function.
+** The memory pointed to by the character pointers returned for the
+** declaration type and collation sequence is valid only until the next
+** call to any SQLite API function.
 **
-** If the specified table is actually a view, then an error is returned.
+** If the specified table is actually a view, an [error code] is returned.
 **
-** If the specified column is "rowid", "oid" or "_rowid_" and an 
-** INTEGER PRIMARY KEY column has been explicitly declared, then the output 
+** If the specified column is "rowid", "oid" or "_rowid_" and an
+** INTEGER PRIMARY KEY column has been explicitly declared, then the output
 ** parameters are set for the explicitly declared column. If there is no
-** explicitly declared IPK column, then the output parameters are set as 
-** follows:
+** explicitly declared INTEGER PRIMARY KEY column, then the output
+** parameters are set as follows:
 **
 ** 
       **     data type: "INTEGER"
@@ -4985,11 +5762,11 @@ SQLITE_API void sqlite3_soft_heap_limit(int);
 **
 ** This function may load one or more schemas from database files. If an
 ** error occurs during this process, or if the requested table or column
-** cannot be found, an SQLITE error code is returned and an error message
-** left in the database handle (to be retrieved using sqlite3_errmsg()).
+** cannot be found, an [error code] is returned and an error message left
+** in the [database connection] (to be retrieved using sqlite3_errmsg()).
 **
 ** This API is only available if the library was compiled with the
-** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined.
+** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
 */
 SQLITE_API int sqlite3_table_column_metadata(
   sqlite3 *db,                /* Connection handle */
@@ -5004,27 +5781,30 @@ SQLITE_API int sqlite3_table_column_metadata(
 );
 
 /*
-** CAPI3REF: Load An Extension {F12600}
+** CAPI3REF: Load An Extension {H12600} 
+**
+** This interface loads an SQLite extension library from the named file.
 **
-** {F12601} The sqlite3_load_extension() interface
-** attempts to load an SQLite extension library contained in the file
-** zFile. {F12602} The entry point is zProc. {F12603} zProc may be 0
-** in which case the name of the entry point defaults
-** to "sqlite3_extension_init".
+** {H12601} The sqlite3_load_extension() interface attempts to load an
+**          SQLite extension library contained in the file zFile.
 **
-** {F12604} The sqlite3_load_extension() interface shall
-** return [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
+** {H12602} The entry point is zProc.
 **
-** {F12605}
-** If an error occurs and pzErrMsg is not 0, then the
-** sqlite3_load_extension() interface shall attempt to fill *pzErrMsg with 
-** error message text stored in memory obtained from [sqlite3_malloc()].
-** {END}  The calling function should free this memory
-** by calling [sqlite3_free()].
+** {H12603} zProc may be 0, in which case the name of the entry point
+**          defaults to "sqlite3_extension_init".
 **
-** {F12606}
-** Extension loading must be enabled using [sqlite3_enable_load_extension()]
-** prior to calling this API or an error will be returned.
+** {H12604} The sqlite3_load_extension() interface shall return
+**          [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
+**
+** {H12605} If an error occurs and pzErrMsg is not 0, then the
+**          [sqlite3_load_extension()] interface shall attempt to
+**          fill *pzErrMsg with error message text stored in memory
+**          obtained from [sqlite3_malloc()]. {END}  The calling function
+**          should free this memory by calling [sqlite3_free()].
+**
+** {H12606} Extension loading must be enabled using
+**          [sqlite3_enable_load_extension()] prior to calling this API,
+**          otherwise an error will be returned.
 */
 SQLITE_API int sqlite3_load_extension(
   sqlite3 *db,          /* Load the extension into this database connection */
@@ -5034,65 +5814,64 @@ SQLITE_API int sqlite3_load_extension(
 );
 
 /*
-** CAPI3REF:  Enable Or Disable Extension Loading {F12620}
+** CAPI3REF: Enable Or Disable Extension Loading {H12620} 
 **
 ** So as not to open security holes in older applications that are
 ** unprepared to deal with extension loading, and as a means of disabling
-** extension loading while evaluating user-entered SQL, the following
-** API is provided to turn the [sqlite3_load_extension()] mechanism on and
-** off.  {F12622} It is off by default. {END} See ticket #1863.
+** extension loading while evaluating user-entered SQL, the following API
+** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
+**
+** Extension loading is off by default. See ticket #1863.
+**
+** {H12621} Call the sqlite3_enable_load_extension() routine with onoff==1
+**          to turn extension loading on and call it with onoff==0 to turn
+**          it back off again.
 **
-** {F12621} Call the sqlite3_enable_load_extension() routine
-** with onoff==1 to turn extension loading on
-** and call it with onoff==0 to turn it back off again. {END}
+** {H12622} Extension loading is off by default.
 */
 SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
 
 /*
-** CAPI3REF: Make Arrangements To Automatically Load An Extension {F12640}
-**
-** {F12641} This function
-** registers an extension entry point that is automatically invoked
-** whenever a new database connection is opened using
-** [sqlite3_open()], [sqlite3_open16()], or [sqlite3_open_v2()]. {END}
+** CAPI3REF: Automatically Load An Extensions {H12640} 
 **
 ** This API can be invoked at program startup in order to register
 ** one or more statically linked extensions that will be available
-** to all new database connections.
+** to all new [database connections]. {END}
 **
-** {F12642} Duplicate extensions are detected so calling this routine multiple
-** times with the same extension is harmless.
+** This routine stores a pointer to the extension in an array that is
+** obtained from [sqlite3_malloc()].  If you run a memory leak checker
+** on your program and it reports a leak because of this array, invoke
+** [sqlite3_reset_auto_extension()] prior to shutdown to free the memory.
 **
-** {F12643} This routine stores a pointer to the extension in an array
-** that is obtained from sqlite_malloc(). {END} If you run a memory leak
-** checker on your program and it reports a leak because of this
-** array, then invoke [sqlite3_reset_auto_extension()] prior
-** to shutdown to free the memory.
+** {H12641} This function registers an extension entry point that is
+**          automatically invoked whenever a new [database connection]
+**          is opened using [sqlite3_open()], [sqlite3_open16()],
+**          or [sqlite3_open_v2()].
 **
-** {F12644} Automatic extensions apply across all threads. {END}
+** {H12642} Duplicate extensions are detected so calling this routine
+**          multiple times with the same extension is harmless.
 **
-** This interface is experimental and is subject to change or
-** removal in future releases of SQLite.
+** {H12643} This routine stores a pointer to the extension in an array
+**          that is obtained from [sqlite3_malloc()].
+**
+** {H12644} Automatic extensions apply across all threads.
 */
 SQLITE_API int sqlite3_auto_extension(void *xEntryPoint);
 
-
 /*
-** CAPI3REF: Reset Automatic Extension Loading {F12660}
+** CAPI3REF: Reset Automatic Extension Loading {H12660} 
 **
-** {F12661} This function disables all previously registered
-** automatic extensions. {END}  This
-** routine undoes the effect of all prior [sqlite3_auto_extension()]
-** calls.
+** This function disables all previously registered automatic
+** extensions. {END}  It undoes the effect of all prior
+** [sqlite3_auto_extension()] calls.
 **
-** {F12662} This call disabled automatic extensions in all threads. {END}
+** {H12661} This function disables all previously registered
+**          automatic extensions.
 **
-** This interface is experimental and is subject to change or
-** removal in future releases of SQLite.
+** {H12662} This function disables automatic extensions in all threads.
 */
 SQLITE_API void sqlite3_reset_auto_extension(void);
 
-
 /*
 ****** EXPERIMENTAL - subject to change without notice **************
 **
@@ -5100,7 +5879,7 @@ SQLITE_API void sqlite3_reset_auto_extension(void);
 ** to be experimental.  The interface might change in incompatible ways.
 ** If this is a problem for you, do not use the interface at this time.
 **
-** When the virtual-table mechanism stablizes, we will declare the
+** When the virtual-table mechanism stabilizes, we will declare the
 ** interface fixed, support it indefinitely, and remove this comment.
 */
 
@@ -5113,12 +5892,16 @@ typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
 typedef struct sqlite3_module sqlite3_module;
 
 /*
-** CAPI3REF: Virtual Table Object {F18000}
+** CAPI3REF: Virtual Table Object {H18000} 
 ** KEYWORDS: sqlite3_module
+** EXPERIMENTAL
 **
 ** A module is a class of virtual tables.  Each module is defined
 ** by an instance of the following structure.  This structure consists
 ** mostly of methods for the module.
+**
+** This interface is experimental and is subject to change or
+** removal in future releases of SQLite.
 */
 struct sqlite3_module {
   int iVersion;
@@ -5147,13 +5930,13 @@ struct sqlite3_module {
   int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
                        void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
                        void **ppArg);
-
   int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
 };
 
 /*
-** CAPI3REF: Virtual Table Indexing Information {F18100}
+** CAPI3REF: Virtual Table Indexing Information {H18100} 
 ** KEYWORDS: sqlite3_index_info
+** EXPERIMENTAL
 **
 ** The sqlite3_index_info structure and its substructures is used to
 ** pass information into and receive the reply from the xBestIndex
@@ -5161,14 +5944,12 @@ struct sqlite3_module {
 ** inputs to xBestIndex and are read-only.  xBestIndex inserts its
 ** results into the **Outputs** fields.
 **
-** The aConstraint[] array records WHERE clause constraints of the
-** form:
+** The aConstraint[] array records WHERE clause constraints of the form:
 **
-**         column OP expr
+** 
      column OP expr
      
 **
-** Where OP is =, <, <=, >, or >=.  
-** The particular operator is stored
-** in aConstraint[].op.  The index of the column is stored in 
+** where OP is =, <, <=, >, or >=.  The particular operator is
+** stored in aConstraint[].op.  The index of the column is stored in
 ** aConstraint[].iColumn.  aConstraint[].usable is TRUE if the
 ** expr on the right-hand side can be evaluated (and thus the constraint
 ** is usable) and false if it cannot.
@@ -5200,6 +5981,9 @@ struct sqlite3_module {
 ** particular lookup.  A full scan of a table with N entries should have
 ** a cost of N.  A binary search of a table of N entries should have a
 ** cost of approximately log(N).
+**
+** This interface is experimental and is subject to change or
+** removal in future releases of SQLite.
 */
 struct sqlite3_index_info {
   /* Inputs */
@@ -5215,7 +5999,6 @@ struct sqlite3_index_info {
      int iColumn;              /* Column number */
      unsigned char desc;       /* True for DESC.  False for ASC. */
   } *aOrderBy;               /* The ORDER BY clause */
-
   /* Outputs */
   struct sqlite3_index_constraint_usage {
     int argvIndex;           /* if >0, constraint is part of argv to xFilter */
@@ -5235,14 +6018,18 @@ struct sqlite3_index_info {
 #define SQLITE_INDEX_CONSTRAINT_MATCH 64
 
 /*
-** CAPI3REF: Register A Virtual Table Implementation {F18200}
+** CAPI3REF: Register A Virtual Table Implementation {H18200} 
+** EXPERIMENTAL
+**
+** This routine is used to register a new module name with a
+** [database connection].  Module names must be registered before
+** creating new virtual tables on the module, or before using
+** preexisting virtual tables of the module.
 **
-** This routine is used to register a new module name with an SQLite
-** connection.  Module names must be registered before creating new
-** virtual tables on the module, or before using preexisting virtual
-** tables of the module.
+** This interface is experimental and is subject to change or
+** removal in future releases of SQLite.
 */
-SQLITE_API int sqlite3_create_module(
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_create_module(
   sqlite3 *db,               /* SQLite connection to register module with */
   const char *zName,         /* Name of the module */
   const sqlite3_module *,    /* Methods for the module */
@@ -5250,13 +6037,14 @@ SQLITE_API int sqlite3_create_module(
 );
 
 /*
-** CAPI3REF: Register A Virtual Table Implementation {F18210}
+** CAPI3REF: Register A Virtual Table Implementation {H18210} 
+** EXPERIMENTAL
 **
-** This routine is identical to the sqlite3_create_module() method above,
+** This routine is identical to the [sqlite3_create_module()] method above,
 ** except that it allows a destructor function to be specified. It is
 ** even more experimental than the rest of the virtual tables API.
 */
-SQLITE_API int sqlite3_create_module_v2(
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_create_module_v2(
   sqlite3 *db,               /* SQLite connection to register module with */
   const char *zName,         /* Name of the module */
   const sqlite3_module *,    /* Methods for the module */
@@ -5265,24 +6053,28 @@ SQLITE_API int sqlite3_create_module_v2(
 );
 
 /*
-** CAPI3REF: Virtual Table Instance Object {F18010}
+** CAPI3REF: Virtual Table Instance Object {H18010} 
 ** KEYWORDS: sqlite3_vtab
+** EXPERIMENTAL
 **
 ** Every module implementation uses a subclass of the following structure
 ** to describe a particular instance of the module.  Each subclass will
-** be tailored to the specific needs of the module implementation.   The
-** purpose of this superclass is to define certain fields that are common
-** to all module implementations.
+** be tailored to the specific needs of the module implementation.
+** The purpose of this superclass is to define certain fields that are
+** common to all module implementations.
 **
 ** Virtual tables methods can set an error message by assigning a
-** string obtained from sqlite3_mprintf() to zErrMsg.  The method should
-** take care that any prior string is freed by a call to sqlite3_free()
+** string obtained from [sqlite3_mprintf()] to zErrMsg.  The method should
+** take care that any prior string is freed by a call to [sqlite3_free()]
 ** prior to assigning a new string to zErrMsg.  After the error message
 ** is delivered up to the client application, the string will be automatically
 ** freed by sqlite3_free() and the zErrMsg field will be zeroed.  Note
 ** that sqlite3_mprintf() and sqlite3_free() are used on the zErrMsg field
 ** since virtual tables are commonly implemented in loadable extensions which
 ** do not have access to sqlite3MPrintf() or sqlite3Free().
+**
+** This interface is experimental and is subject to change or
+** removal in future releases of SQLite.
 */
 struct sqlite3_vtab {
   const sqlite3_module *pModule;  /* The module for this virtual table */
@@ -5292,8 +6084,9 @@ struct sqlite3_vtab {
 };
 
 /*
-** CAPI3REF: Virtual Table Cursor Object  {F18020}
+** CAPI3REF: Virtual Table Cursor Object  {H18020} 
 ** KEYWORDS: sqlite3_vtab_cursor
+** EXPERIMENTAL
 **
 ** Every module implementation uses a subclass of the following structure
 ** to describe cursors that point into the virtual table and are used
@@ -5303,6 +6096,9 @@ struct sqlite3_vtab {
 **
 ** This superclass exists in order to define fields of the cursor that
 ** are common to all implementations.
+**
+** This interface is experimental and is subject to change or
+** removal in future releases of SQLite.
 */
 struct sqlite3_vtab_cursor {
   sqlite3_vtab *pVtab;      /* Virtual table of this cursor */
@@ -5310,16 +6106,21 @@ struct sqlite3_vtab_cursor {
 };
 
 /*
-** CAPI3REF: Declare The Schema Of A Virtual Table {F18280}
+** CAPI3REF: Declare The Schema Of A Virtual Table {H18280} 
+** EXPERIMENTAL
 **
 ** The xCreate and xConnect methods of a module use the following API
 ** to declare the format (the names and datatypes of the columns) of
 ** the virtual tables they implement.
+**
+** This interface is experimental and is subject to change or
+** removal in future releases of SQLite.
 */
-SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);
 
 /*
-** CAPI3REF: Overload A Function For A Virtual Table {F18300}
+** CAPI3REF: Overload A Function For A Virtual Table {H18300} 
+** EXPERIMENTAL
 **
 ** Virtual tables can provide alternative implementations of functions
 ** using the xFindFunction method.  But global versions of those functions
@@ -5330,13 +6131,13 @@ SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);
 ** before this API is called, a new function is created.  The implementation
 ** of the new function always causes an exception to be thrown.  So
 ** the new function is not good for anything by itself.  Its only
-** purpose is to be a place-holder function that can be overloaded
+** purpose is to be a placeholder function that can be overloaded
 ** by virtual tables.
 **
 ** This API should be considered part of the virtual table interface,
 ** which is experimental and subject to change.
 */
-SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
 
 /*
 ** The interface to the virtual-table mechanism defined above (back up
@@ -5351,62 +6152,83 @@ SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nA
 */
 
 /*
-** CAPI3REF: A Handle To An Open BLOB {F17800}
+** CAPI3REF: A Handle To An Open BLOB {H17800} 
+** KEYWORDS: {BLOB handle} {BLOB handles}
 **
 ** An instance of this object represents an open BLOB on which
-** incremental I/O can be preformed.
-** Objects of this type are created by
-** [sqlite3_blob_open()] and destroyed by [sqlite3_blob_close()].
+** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
+** Objects of this type are created by [sqlite3_blob_open()]
+** and destroyed by [sqlite3_blob_close()].
 ** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
-** can be used to read or write small subsections of the blob.
-** The [sqlite3_blob_bytes()] interface returns the size of the
-** blob in bytes.
+** can be used to read or write small subsections of the BLOB.
+** The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
 */
 typedef struct sqlite3_blob sqlite3_blob;
 
 /*
-** CAPI3REF: Open A BLOB For Incremental I/O {F17810}
+** CAPI3REF: Open A BLOB For Incremental I/O {H17810} 
 **
-** This interfaces opens a handle to the blob located
-** in row iRow,, column zColumn, table zTable in database zDb;
-** in other words,  the same blob that would be selected by:
+** This interfaces opens a [BLOB handle | handle] to the BLOB located
+** in row iRow, column zColumn, table zTable in database zDb;
+** in other words, the same BLOB that would be selected by:
 **
 ** 
       **     SELECT zColumn FROM zDb.zTable WHERE rowid = iRow;
 ** 
       {END}
 **
-** If the flags parameter is non-zero, the blob is opened for 
-** read and write access. If it is zero, the blob is opened for read 
-** access.
+** If the flags parameter is non-zero, the the BLOB is opened for read
+** and write access. If it is zero, the BLOB is opened for read access.
+**
+** Note that the database name is not the filename that contains
+** the database but rather the symbolic name of the database that
+** is assigned when the database is connected using [ATTACH].
+** For the main database file, the database name is "main".
+** For TEMP tables, the database name is "temp".
 **
-** On success, [SQLITE_OK] is returned and the new 
-** [sqlite3_blob | blob handle] is written to *ppBlob. 
-** Otherwise an error code is returned and 
-** any value written to *ppBlob should not be used by the caller.
-** This function sets the database-handle error code and message
+** On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
+** to *ppBlob. Otherwise an [error code] is returned and any value written
+** to *ppBlob should not be used by the caller.
+** This function sets the [database connection] error code and message
 ** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()].
-** 
+**
+** If the row that a BLOB handle points to is modified by an
+** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
+** then the BLOB handle is marked as "expired".
+** This is true if any column of the row is changed, even a column
+** other than the one the BLOB handle is open on.
+** Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
+** a expired BLOB handle fail with an return code of [SQLITE_ABORT].
+** Changes written into a BLOB prior to the BLOB expiring are not
+** rollback by the expiration of the BLOB.  Such changes will eventually
+** commit if the transaction continues to completion.
+**
 ** INVARIANTS:
 **
-** {F17813} A successful invocation of the [sqlite3_blob_open(D,B,T,C,R,F,P)]
-**          interface opens an [sqlite3_blob] object P on the blob
-**          in column C of table T in database B on [database connection] D.
+** {H17813} A successful invocation of the [sqlite3_blob_open(D,B,T,C,R,F,P)]
+**          interface shall open an [sqlite3_blob] object P on the BLOB
+**          in column C of the table T in the database B on
+**          the [database connection] D.
 **
-** {F17814} A successful invocation of [sqlite3_blob_open(D,...)] starts
-**          a new transaction on [database connection] D if that connection
-**          is not already in a transaction.
+** {H17814} A successful invocation of [sqlite3_blob_open(D,...)] shall start
+**          a new transaction on the [database connection] D if that
+**          connection is not already in a transaction.
 **
-** {F17816} The [sqlite3_blob_open(D,B,T,C,R,F,P)] interface opens the blob
-**          for read and write access if and only if the F parameter
-**          is non-zero.
+** {H17816} The [sqlite3_blob_open(D,B,T,C,R,F,P)] interface shall open
+**          the BLOB for read and write access if and only if the F
+**          parameter is non-zero.
 **
-** {F17819} The [sqlite3_blob_open()] interface returns [SQLITE_OK] on 
+** {H17819} The [sqlite3_blob_open()] interface shall return [SQLITE_OK] on
 **          success and an appropriate [error code] on failure.
 **
-** {F17821} If an error occurs during evaluation of [sqlite3_blob_open(D,...)]
+** {H17821} If an error occurs during evaluation of [sqlite3_blob_open(D,...)]
 **          then subsequent calls to [sqlite3_errcode(D)],
-**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return
-**          information approprate for that error.
+**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
+**          information appropriate for that error.
+**
+** {H17824} If any column in the row that a [sqlite3_blob] has open is
+**          changed by a separate [UPDATE] or [DELETE] statement or by
+**          an [ON CONFLICT] side effect, then the [sqlite3_blob] shall
+**          be marked as invalid.
 */
 SQLITE_API int sqlite3_blob_open(
   sqlite3*,
@@ -5419,18 +6241,19 @@ SQLITE_API int sqlite3_blob_open(
 );
 
 /*
-** CAPI3REF:  Close A BLOB Handle {F17830}
+** CAPI3REF: Close A BLOB Handle {H17830} 
 **
-** Close an open [sqlite3_blob | blob handle].
+** Closes an open [BLOB handle].
 **
 ** Closing a BLOB shall cause the current transaction to commit
 ** if there are no other BLOBs, no pending prepared statements, and the
-** database connection is in autocommit mode.
+** database connection is in [autocommit mode].
 ** If any writes were made to the BLOB, they might be held in cache
 ** until the close operation if they will fit. {END}
+**
 ** Closing the BLOB often forces the changes
 ** out to disk and so if any I/O errors occur, they will likely occur
-** at the time when the BLOB is closed.  {F17833} Any errors that occur during
+** at the time when the BLOB is closed.  {H17833} Any errors that occur during
 ** closing are reported as a non-zero return value.
 **
 ** The BLOB is closed unconditionally.  Even if this routine returns
@@ -5438,138 +6261,156 @@ SQLITE_API int sqlite3_blob_open(
 **
 ** INVARIANTS:
 **
-** {F17833} The [sqlite3_blob_close(P)] interface closes an
-**          [sqlite3_blob] object P previously opened using
-**          [sqlite3_blob_open()].
+** {H17833} The [sqlite3_blob_close(P)] interface closes an [sqlite3_blob]
+**          object P previously opened using [sqlite3_blob_open()].
 **
-** {F17836} Closing an [sqlite3_blob] object using
+** {H17836} Closing an [sqlite3_blob] object using
 **          [sqlite3_blob_close()] shall cause the current transaction to
 **          commit if there are no other open [sqlite3_blob] objects
 **          or [prepared statements] on the same [database connection] and
-**          the [database connection] is in
-**          [sqlite3_get_autocommit | autocommit mode].
+**          the database connection is in [autocommit mode].
 **
-** {F17839} The [sqlite3_blob_close(P)] interfaces closes the 
+** {H17839} The [sqlite3_blob_close(P)] interfaces shall close the
 **          [sqlite3_blob] object P unconditionally, even if
 **          [sqlite3_blob_close(P)] returns something other than [SQLITE_OK].
-**          
 */
 SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
 
 /*
-** CAPI3REF:  Return The Size Of An Open BLOB {F17840}
+** CAPI3REF: Return The Size Of An Open BLOB {H17840} 
 **
-** Return the size in bytes of the blob accessible via the open 
-** [sqlite3_blob] object in its only argument.
+** Returns the size in bytes of the BLOB accessible via the open
+** []BLOB handle] in its only argument.
 **
 ** INVARIANTS:
 **
-** {F17843} The [sqlite3_blob_bytes(P)] interface returns the size
+** {H17843} The [sqlite3_blob_bytes(P)] interface returns the size
 **          in bytes of the BLOB that the [sqlite3_blob] object P
 **          refers to.
 */
 SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
 
 /*
-** CAPI3REF:  Read Data From A BLOB Incrementally {F17850}
+** CAPI3REF: Read Data From A BLOB Incrementally {H17850} 
 **
-** This function is used to read data from an open 
-** [sqlite3_blob | blob-handle] into a caller supplied buffer.
-** N bytes of data are copied into buffer
-** Z from the open blob, starting at offset iOffset.
+** This function is used to read data from an open [BLOB handle] into a
+** caller-supplied buffer. N bytes of data are copied into buffer Z
+** from the open BLOB, starting at offset iOffset.
 **
-** If offset iOffset is less than N bytes from the end of the blob, 
+** If offset iOffset is less than N bytes from the end of the BLOB,
 ** [SQLITE_ERROR] is returned and no data is read.  If N or iOffset is
-** less than zero [SQLITE_ERROR] is returned and no data is read.
+** less than zero, [SQLITE_ERROR] is returned and no data is read.
 **
-** On success, SQLITE_OK is returned. Otherwise, an 
-** [error code] or an [extended error code] is returned.
+** An attempt to read from an expired [BLOB handle] fails with an
+** error code of [SQLITE_ABORT].
+**
+** On success, SQLITE_OK is returned.
+** Otherwise, an [error code] or an [extended error code] is returned.
 **
 ** INVARIANTS:
 **
-** {F17853} The [sqlite3_blob_read(P,Z,N,X)] interface reads N bytes
-**          beginning at offset X from
-**          the blob that [sqlite3_blob] object P refers to
-**          and writes those N bytes into buffer Z.
+** {H17853} A successful invocation of [sqlite3_blob_read(P,Z,N,X)] 
+**          shall reads N bytes of data out of the BLOB referenced by
+**          [BLOB handle] P beginning at offset X and store those bytes
+**          into buffer Z.
+**
+** {H17856} In [sqlite3_blob_read(P,Z,N,X)] if the size of the BLOB
+**          is less than N+X bytes, then the function shall leave the
+**          Z buffer unchanged and return [SQLITE_ERROR].
 **
-** {F17856} In [sqlite3_blob_read(P,Z,N,X)] if the size of the blob
-**          is less than N+X bytes, then the function returns [SQLITE_ERROR]
-**          and nothing is read from the blob.
+** {H17859} In [sqlite3_blob_read(P,Z,N,X)] if X or N is less than zero
+**          then the function shall leave the Z buffer unchanged
+**          and return [SQLITE_ERROR].
 **
-** {F17859} In [sqlite3_blob_read(P,Z,N,X)] if X or N is less than zero
-**          then the function returns [SQLITE_ERROR]
-**          and nothing is read from the blob.
+** {H17862} The [sqlite3_blob_read(P,Z,N,X)] interface shall return [SQLITE_OK]
+**          if N bytes are successfully read into buffer Z.
 **
-** {F17862} The [sqlite3_blob_read(P,Z,N,X)] interface returns [SQLITE_OK]
-**          if N bytes where successfully read into buffer Z.
+** {H17863} If the [BLOB handle] P is expired and X and N are within bounds
+**          then [sqlite3_blob_read(P,Z,N,X)] shall leave the Z buffer
+**          unchanged and return [SQLITE_ABORT].
 **
-** {F17865} If the requested read could not be completed,
-**          the [sqlite3_blob_read(P,Z,N,X)] interface returns an
+** {H17865} If the requested read could not be completed,
+**          the [sqlite3_blob_read(P,Z,N,X)] interface shall return an
 **          appropriate [error code] or [extended error code].
 **
-** {F17868} If an error occurs during evaluation of [sqlite3_blob_read(D,...)]
+** {H17868} If an error occurs during evaluation of [sqlite3_blob_read(P,...)]
 **          then subsequent calls to [sqlite3_errcode(D)],
-**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return
-**          information approprate for that error.
+**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
+**          information appropriate for that error, where D is the
+**          [database connection] that was used to open the [BLOB handle] P.
 */
 SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
 
 /*
-** CAPI3REF:  Write Data Into A BLOB Incrementally {F17870}
+** CAPI3REF: Write Data Into A BLOB Incrementally {H17870} 
 **
-** This function is used to write data into an open 
-** [sqlite3_blob | blob-handle] from a user supplied buffer.
-** n bytes of data are copied from the buffer
-** pointed to by z into the open blob, starting at offset iOffset.
+** This function is used to write data into an open [BLOB handle] from a
+** caller-supplied buffer. N bytes of data are copied from the buffer Z
+** into the open BLOB, starting at offset iOffset.
 **
-** If the [sqlite3_blob | blob-handle] passed as the first argument
-** was not opened for writing (the flags parameter to [sqlite3_blob_open()]
-*** was zero), this function returns [SQLITE_READONLY].
+** If the [BLOB handle] passed as the first argument was not opened for
+** writing (the flags parameter to [sqlite3_blob_open()] was zero),
+** this function returns [SQLITE_READONLY].
 **
-** This function may only modify the contents of the blob; it is
-** not possible to increase the size of a blob using this API.
-** If offset iOffset is less than n bytes from the end of the blob, 
-** [SQLITE_ERROR] is returned and no data is written.  If n is
+** This function may only modify the contents of the BLOB; it is
+** not possible to increase the size of a BLOB using this API.
+** If offset iOffset is less than N bytes from the end of the BLOB,
+** [SQLITE_ERROR] is returned and no data is written.  If N is
 ** less than zero [SQLITE_ERROR] is returned and no data is written.
 **
-** On success, SQLITE_OK is returned. Otherwise, an 
-** [error code] or an [extended error code] is returned.
+** An attempt to write to an expired [BLOB handle] fails with an
+** error code of [SQLITE_ABORT].  Writes to the BLOB that occurred
+** before the [BLOB handle] expired are not rolled back by the
+** expiration of the handle, though of course those changes might
+** have been overwritten by the statement that expired the BLOB handle
+** or by other independent statements.
+**
+** On success, SQLITE_OK is returned.
+** Otherwise, an  [error code] or an [extended error code] is returned.
 **
 ** INVARIANTS:
 **
-** {F17873} The [sqlite3_blob_write(P,Z,N,X)] interface writes N bytes
-**          from buffer Z into
-**          the blob that [sqlite3_blob] object P refers to
-**          beginning at an offset of X into the blob.
+** {H17873} A successful invocation of [sqlite3_blob_write(P,Z,N,X)]
+**          shall write N bytes of data from buffer Z into the BLOB 
+**          referenced by [BLOB handle] P beginning at offset X into
+**          the BLOB.
+**
+** {H17874} In the absence of other overridding changes, the changes
+**          written to a BLOB by [sqlite3_blob_write()] shall
+**          remain in effect after the associated [BLOB handle] expires.
 **
-** {F17875} The [sqlite3_blob_write(P,Z,N,X)] interface returns
-**          [SQLITE_READONLY] if the [sqlite3_blob] object P was
-**          [sqlite3_blob_open | opened] for reading only.
+** {H17875} If the [BLOB handle] P was opened for reading only then
+**          an invocation of [sqlite3_blob_write(P,Z,N,X)] shall leave
+**          the referenced BLOB unchanged and return [SQLITE_READONLY].
 **
-** {F17876} In [sqlite3_blob_write(P,Z,N,X)] if the size of the blob
-**          is less than N+X bytes, then the function returns [SQLITE_ERROR]
-**          and nothing is written into the blob.
+** {H17876} If the size of the BLOB referenced by [BLOB handle] P is
+**          less than N+X bytes then [sqlite3_blob_write(P,Z,N,X)] shall
+**          leave the BLOB unchanged and return [SQLITE_ERROR].
 **
-** {F17879} In [sqlite3_blob_write(P,Z,N,X)] if X or N is less than zero
-**          then the function returns [SQLITE_ERROR]
-**          and nothing is written into the blob.
+** {H17877} If the [BLOB handle] P is expired and X and N are within bounds
+**          then [sqlite3_blob_read(P,Z,N,X)] shall leave the BLOB
+**          unchanged and return [SQLITE_ABORT].
 **
-** {F17882} The [sqlite3_blob_write(P,Z,N,X)] interface returns [SQLITE_OK]
-**          if N bytes where successfully written into blob.
+** {H17879} If X or N are less than zero then [sqlite3_blob_write(P,Z,N,X)]
+**          shall leave the BLOB referenced by [BLOB handle] P unchanged
+**          and return [SQLITE_ERROR].
 **
-** {F17885} If the requested write could not be completed,
-**          the [sqlite3_blob_write(P,Z,N,X)] interface returns an
+** {H17882} The [sqlite3_blob_write(P,Z,N,X)] interface shall return
+**          [SQLITE_OK] if N bytes where successfully written into the BLOB.
+**
+** {H17885} If the requested write could not be completed,
+**          the [sqlite3_blob_write(P,Z,N,X)] interface shall return an
 **          appropriate [error code] or [extended error code].
 **
-** {F17888} If an error occurs during evaluation of [sqlite3_blob_write(D,...)]
+** {H17888} If an error occurs during evaluation of [sqlite3_blob_write(D,...)]
 **          then subsequent calls to [sqlite3_errcode(D)],
-**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return
-**          information approprate for that error.
+**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
+**          information appropriate for that error.
 */
 SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
 
 /*
-** CAPI3REF:  Virtual File System Objects {F11200}
+** CAPI3REF: Virtual File System Objects {H11200} 
 **
 ** A virtual filesystem (VFS) is an [sqlite3_vfs] object
 ** that SQLite uses to interact
@@ -5578,12 +6419,11 @@ SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOff
 ** New VFSes can be registered and existing VFSes can be unregistered.
 ** The following interfaces are provided.
 **
-** The sqlite3_vfs_find() interface returns a pointer to 
-** a VFS given its name.  Names are case sensitive.
+** The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
+** Names are case sensitive.
 ** Names are zero-terminated UTF-8 strings.
-** If there is no match, a NULL
-** pointer is returned.  If zVfsName is NULL then the default 
-** VFS is returned. 
+** If there is no match, a NULL pointer is returned.
+** If zVfsName is NULL then the default VFS is returned.
 **
 ** New VFSes are registered with sqlite3_vfs_register().
 ** Each new VFS becomes the default VFS if the makeDflt flag is set.
@@ -5593,35 +6433,34 @@ SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOff
 ** same name are registered, the behavior is undefined.  If a
 ** VFS is registered with a name that is NULL or an empty string,
 ** then the behavior is undefined.
-** 
+**
 ** Unregister a VFS with the sqlite3_vfs_unregister() interface.
 ** If the default VFS is unregistered, another VFS is chosen as
 ** the default.  The choice for the new VFS is arbitrary.
 **
 ** INVARIANTS:
 **
-** {F11203} The [sqlite3_vfs_find(N)] interface returns a pointer to the
+** {H11203} The [sqlite3_vfs_find(N)] interface returns a pointer to the
 **          registered [sqlite3_vfs] object whose name exactly matches
 **          the zero-terminated UTF-8 string N, or it returns NULL if
 **          there is no match.
 **
-** {F11206} If the N parameter to [sqlite3_vfs_find(N)] is NULL then
+** {H11206} If the N parameter to [sqlite3_vfs_find(N)] is NULL then
 **          the function returns a pointer to the default [sqlite3_vfs]
-**          object if there is one, or NULL if there is no default 
+**          object if there is one, or NULL if there is no default
 **          [sqlite3_vfs] object.
 **
-** {F11209} The [sqlite3_vfs_register(P,F)] interface registers the
+** {H11209} The [sqlite3_vfs_register(P,F)] interface registers the
 **          well-formed [sqlite3_vfs] object P using the name given
 **          by the zName field of the object.
 **
-** {F11212} Using the [sqlite3_vfs_register(P,F)] interface to register
+** {H11212} Using the [sqlite3_vfs_register(P,F)] interface to register
 **          the same [sqlite3_vfs] object multiple times is a harmless no-op.
 **
-** {F11215} The [sqlite3_vfs_register(P,F)] interface makes the
-**          the [sqlite3_vfs] object P the default [sqlite3_vfs] object
-**          if F is non-zero.
+** {H11215} The [sqlite3_vfs_register(P,F)] interface makes the [sqlite3_vfs]
+**          object P the default [sqlite3_vfs] object if F is non-zero.
 **
-** {F11218} The [sqlite3_vfs_unregister(P)] interface unregisters the
+** {H11218} The [sqlite3_vfs_unregister(P)] interface unregisters the
 **          [sqlite3_vfs] object P so that it is no longer returned by
 **          subsequent calls to [sqlite3_vfs_find()].
 */
@@ -5630,14 +6469,14 @@ SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
 SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
 
 /*
-** CAPI3REF: Mutexes {F17000}
+** CAPI3REF: Mutexes {H17000} 
 **
 ** The SQLite core uses these routines for thread
-** synchronization.  Though they are intended for internal
+** synchronization. Though they are intended for internal
 ** use by SQLite, code that links against SQLite is
 ** permitted to use any of these routines.
 **
-** The SQLite source code contains multiple implementations 
+** The SQLite source code contains multiple implementations
 ** of these mutex routines.  An appropriate implementation
 ** is selected automatically at compile-time.  The following
 ** implementations are available in the SQLite core:
@@ -5649,25 +6488,24 @@ SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
 ** 
    •    SQLITE_MUTEX_NOOP
 ** 
 **
-** The SQLITE_MUTEX_NOOP implementation is a set of routines 
-** that does no real locking and is appropriate for use in 
+** The SQLITE_MUTEX_NOOP implementation is a set of routines
+** that does no real locking and is appropriate for use in
 ** a single-threaded application.  The SQLITE_MUTEX_OS2,
 ** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations
-** are appropriate for use on os/2, unix, and windows.
-** 
+** are appropriate for use on OS/2, Unix, and Windows.
+**
 ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
 ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
-** implementation is included with the library.  The
-** mutex interface routines defined here become external
-** references in the SQLite library for which implementations
-** must be provided by the application.  This facility allows an
-** application that links against SQLite to provide its own mutex
-** implementation without having to modify the SQLite core.
-**
-** {F17011} The sqlite3_mutex_alloc() routine allocates a new
-** mutex and returns a pointer to it. {F17012} If it returns NULL
-** that means that a mutex could not be allocated. {F17013} SQLite
-** will unwind its stack and return an error. {F17014} The argument
+** implementation is included with the library. In this case the
+** application must supply a custom mutex implementation using the
+** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
+** before calling sqlite3_initialize() or any other public sqlite3_
+** function that calls sqlite3_initialize().
+**
+** {H17011} The sqlite3_mutex_alloc() routine allocates a new
+** mutex and returns a pointer to it. {H17012} If it returns NULL
+** that means that a mutex could not be allocated. {H17013} SQLite
+** will unwind its stack and return an error. {H17014} The argument
 ** to sqlite3_mutex_alloc() is one of these integer constants:
 **
 ** 
        
@@ -5678,19 +6516,20 @@ SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
 ** 
      •   SQLITE_MUTEX_STATIC_MEM2
 ** 
      •   SQLITE_MUTEX_STATIC_PRNG
 ** 
      •   SQLITE_MUTEX_STATIC_LRU
-** 
       {END}
+** 
    •   SQLITE_MUTEX_STATIC_LRU2
+** 
 **
-** {F17015} The first two constants cause sqlite3_mutex_alloc() to create
+** {H17015} The first two constants cause sqlite3_mutex_alloc() to create
 ** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
 ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. {END}
 ** The mutex implementation does not need to make a distinction
 ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
-** not want to.  {F17016} But SQLite will only request a recursive mutex in
+** not want to.  {H17016} But SQLite will only request a recursive mutex in
 ** cases where it really needs one.  {END} If a faster non-recursive mutex
 ** implementation is available on the host platform, the mutex subsystem
 ** might return such a mutex in response to SQLITE_MUTEX_FAST.
 **
-** {F17017} The other allowed parameters to sqlite3_mutex_alloc() each return
+** {H17017} The other allowed parameters to sqlite3_mutex_alloc() each return
 ** a pointer to a static preexisting mutex. {END}  Four static mutexes are
 ** used by the current version of SQLite.  Future versions of SQLite
 ** may add additional static mutexes.  Static mutexes are for internal
@@ -5698,43 +6537,47 @@ SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
 ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
 ** SQLITE_MUTEX_RECURSIVE.
 **
-** {F17018} Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
+** {H17018} Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
 ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
-** returns a different mutex on every call.  {F17034} But for the static 
+** returns a different mutex on every call.  {H17034} But for the static
 ** mutex types, the same mutex is returned on every call that has
-** the same type number. {END}
+** the same type number.
 **
-** {F17019} The sqlite3_mutex_free() routine deallocates a previously
-** allocated dynamic mutex. {F17020} SQLite is careful to deallocate every
-** dynamic mutex that it allocates. {U17021} The dynamic mutexes must not be in 
-** use when they are deallocated. {U17022} Attempting to deallocate a static
-** mutex results in undefined behavior. {F17023} SQLite never deallocates
+** {H17019} The sqlite3_mutex_free() routine deallocates a previously
+** allocated dynamic mutex. {H17020} SQLite is careful to deallocate every
+** dynamic mutex that it allocates. {A17021} The dynamic mutexes must not be in
+** use when they are deallocated. {A17022} Attempting to deallocate a static
+** mutex results in undefined behavior. {H17023} SQLite never deallocates
 ** a static mutex. {END}
 **
 ** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
-** to enter a mutex. {F17024} If another thread is already within the mutex,
+** to enter a mutex. {H17024} If another thread is already within the mutex,
 ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
-** SQLITE_BUSY. {F17025}  The sqlite3_mutex_try() interface returns SQLITE_OK
-** upon successful entry.  {F17026} Mutexes created using
+** SQLITE_BUSY. {H17025}  The sqlite3_mutex_try() interface returns [SQLITE_OK]
+** upon successful entry.  {H17026} Mutexes created using
 ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
-** {F17027} In such cases the,
+** {H17027} In such cases the,
 ** mutex must be exited an equal number of times before another thread
-** can enter.  {U17028} If the same thread tries to enter any other
+** can enter.  {A17028} If the same thread tries to enter any other
 ** kind of mutex more than once, the behavior is undefined.
-** {F17029} SQLite will never exhibit
-** such behavior in its own use of mutexes. {END}
+** {H17029} SQLite will never exhibit
+** such behavior in its own use of mutexes.
 **
-** Some systems (ex: windows95) do not the operation implemented by
-** sqlite3_mutex_try().  On those systems, sqlite3_mutex_try() will
-** always return SQLITE_BUSY.  {F17030} The SQLite core only ever uses
-** sqlite3_mutex_try() as an optimization so this is acceptable behavior. {END}
+** Some systems (for example, Windows 95) do not support the operation
+** implemented by sqlite3_mutex_try().  On those systems, sqlite3_mutex_try()
+** will always return SQLITE_BUSY.  {H17030} The SQLite core only ever uses
+** sqlite3_mutex_try() as an optimization so this is acceptable behavior.
 **
-** {F17031} The sqlite3_mutex_leave() routine exits a mutex that was
-** previously entered by the same thread.  {U17032} The behavior
+** {H17031} The sqlite3_mutex_leave() routine exits a mutex that was
+** previously entered by the same thread.  {A17032} The behavior
 ** is undefined if the mutex is not currently entered by the
-** calling thread or is not currently allocated.  {F17033} SQLite will
+** calling thread or is not currently allocated.  {H17033} SQLite will
 ** never do either. {END}
 **
+** If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
+** sqlite3_mutex_leave() is a NULL pointer, then all three routines
+** behave as no-ops.
+**
 ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
 */
 SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
@@ -5744,44 +6587,110 @@ SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
 SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
 
 /*
-** CAPI3REF: Mutex Verifcation Routines {F17080}
+** CAPI3REF: Mutex Methods Object {H17120} 
+** EXPERIMENTAL
+**
+** An instance of this structure defines the low-level routines
+** used to allocate and use mutexes.
+**
+** Usually, the default mutex implementations provided by SQLite are
+** sufficient, however the user has the option of substituting a custom
+** implementation for specialized deployments or systems for which SQLite
+** does not provide a suitable implementation. In this case, the user
+** creates and populates an instance of this structure to pass
+** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
+** Additionally, an instance of this structure can be used as an
+** output variable when querying the system for the current mutex
+** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
+**
+** The xMutexInit method defined by this structure is invoked as
+** part of system initialization by the sqlite3_initialize() function.
+** {H17001} The xMutexInit routine shall be called by SQLite once for each
+** effective call to [sqlite3_initialize()].
+**
+** The xMutexEnd method defined by this structure is invoked as
+** part of system shutdown by the sqlite3_shutdown() function. The
+** implementation of this method is expected to release all outstanding
+** resources obtained by the mutex methods implementation, especially
+** those obtained by the xMutexInit method. {H17003} The xMutexEnd()
+** interface shall be invoked once for each call to [sqlite3_shutdown()].
+**
+** The remaining seven methods defined by this structure (xMutexAlloc,
+** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
+** xMutexNotheld) implement the following interfaces (respectively):
+**
+** 
        
+**   
      •   [sqlite3_mutex_alloc()] 
        • 
+**   
      •   [sqlite3_mutex_free()] 
        • 
+**   
      •   [sqlite3_mutex_enter()] 
        • 
+**   
      •   [sqlite3_mutex_try()] 
        • 
+**   
      •   [sqlite3_mutex_leave()] 
        • 
+**   
      •   [sqlite3_mutex_held()] 
        • 
+**   
      •   [sqlite3_mutex_notheld()] 
        • 
+** 
      
+**
+** The only difference is that the public sqlite3_XXX functions enumerated
+** above silently ignore any invocations that pass a NULL pointer instead
+** of a valid mutex handle. The implementations of the methods defined
+** by this structure are not required to handle this case, the results
+** of passing a NULL pointer instead of a valid mutex handle are undefined
+** (i.e. it is acceptable to provide an implementation that segfaults if
+** it is passed a NULL pointer).
+*/
+typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
+struct sqlite3_mutex_methods {
+  int (*xMutexInit)(void);
+  int (*xMutexEnd)(void);
+  sqlite3_mutex *(*xMutexAlloc)(int);
+  void (*xMutexFree)(sqlite3_mutex *);
+  void (*xMutexEnter)(sqlite3_mutex *);
+  int (*xMutexTry)(sqlite3_mutex *);
+  void (*xMutexLeave)(sqlite3_mutex *);
+  int (*xMutexHeld)(sqlite3_mutex *);
+  int (*xMutexNotheld)(sqlite3_mutex *);
+};
+
+/*
+** CAPI3REF: Mutex Verification Routines {H17080}  
 **
 ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
-** are intended for use inside assert() statements. {F17081} The SQLite core
+** are intended for use inside assert() statements. {H17081} The SQLite core
 ** never uses these routines except inside an assert() and applications
-** are advised to follow the lead of the core.  {F17082} The core only
+** are advised to follow the lead of the core.  {H17082} The core only
 ** provides implementations for these routines when it is compiled
-** with the SQLITE_DEBUG flag.  {U17087} External mutex implementations
+** with the SQLITE_DEBUG flag.  {A17087} External mutex implementations
 ** are only required to provide these routines if SQLITE_DEBUG is
 ** defined and if NDEBUG is not defined.
 **
-** {F17083} These routines should return true if the mutex in their argument
-** is held or not held, respectively, by the calling thread. {END}
+** {H17083} These routines should return true if the mutex in their argument
+** is held or not held, respectively, by the calling thread.
 **
 ** {X17084} The implementation is not required to provided versions of these
-** routines that actually work.
-** If the implementation does not provide working
-** versions of these routines, it should at least provide stubs
-** that always return true so that one does not get spurious
-** assertion failures. {END}
+** routines that actually work. If the implementation does not provide working
+** versions of these routines, it should at least provide stubs that always
+** return true so that one does not get spurious assertion failures.
 **
-** {F17085} If the argument to sqlite3_mutex_held() is a NULL pointer then
+** {H17085} If the argument to sqlite3_mutex_held() is a NULL pointer then
 ** the routine should return 1.  {END} This seems counter-intuitive since
 ** clearly the mutex cannot be held if it does not exist.  But the
 ** the reason the mutex does not exist is because the build is not
 ** using mutexes.  And we do not want the assert() containing the
 ** call to sqlite3_mutex_held() to fail, so a non-zero return is
-** the appropriate thing to do.  {F17086} The sqlite3_mutex_notheld() 
+** the appropriate thing to do.  {H17086} The sqlite3_mutex_notheld()
 ** interface should also return 1 when given a NULL pointer.
 */
 SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
 SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
 
 /*
-** CAPI3REF: Mutex Types {F17001}
+** CAPI3REF: Mutex Types {H17001} 
+**
+** The [sqlite3_mutex_alloc()] interface takes a single argument
+** which is one of these integer constants.
 **
-** {F17002} The [sqlite3_mutex_alloc()] interface takes a single argument
-** which is one of these integer constants. {END}
+** The set of static mutexes may change from one SQLite release to the
+** next.  Applications that override the built-in mutex logic must be
+** prepared to accommodate additional static mutexes.
 */
 #define SQLITE_MUTEX_FAST             0
 #define SQLITE_MUTEX_RECURSIVE        1
@@ -5790,26 +6699,27 @@ SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
 #define SQLITE_MUTEX_STATIC_MEM2      4  /* sqlite3_release_memory() */
 #define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_random() */
 #define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
+#define SQLITE_MUTEX_STATIC_LRU2      7  /* lru page list */
 
 /*
-** CAPI3REF: Low-Level Control Of Database Files {F11300}
+** CAPI3REF: Low-Level Control Of Database Files {H11300} 
 **
-** {F11301} The [sqlite3_file_control()] interface makes a direct call to the
+** {H11301} The [sqlite3_file_control()] interface makes a direct call to the
 ** xFileControl method for the [sqlite3_io_methods] object associated
-** with a particular database identified by the second argument. {F11302} The
+** with a particular database identified by the second argument. {H11302} The
 ** name of the database is the name assigned to the database by the
 ** ATTACH SQL command that opened the
-** database. {F11303} To control the main database file, use the name "main"
-** or a NULL pointer. {F11304} The third and fourth parameters to this routine
+** database. {H11303} To control the main database file, use the name "main"
+** or a NULL pointer. {H11304} The third and fourth parameters to this routine
 ** are passed directly through to the second and third parameters of
-** the xFileControl method.  {F11305} The return value of the xFileControl
+** the xFileControl method.  {H11305} The return value of the xFileControl
 ** method becomes the return value of this routine.
 **
-** {F11306} If the second parameter (zDbName) does not match the name of any
-** open database file, then SQLITE_ERROR is returned. {F11307} This error
+** {H11306} If the second parameter (zDbName) does not match the name of any
+** open database file, then SQLITE_ERROR is returned. {H11307} This error
 ** code is not remembered and will not be recalled by [sqlite3_errcode()]
-** or [sqlite3_errmsg()]. {U11308} The underlying xFileControl method might
-** also return SQLITE_ERROR.  {U11309} There is no way to distinguish between
+** or [sqlite3_errmsg()]. {A11308} The underlying xFileControl method might
+** also return SQLITE_ERROR.  {A11309} There is no way to distinguish between
 ** an incorrect zDbName and an SQLITE_ERROR return from the underlying
 ** xFileControl method. {END}
 **
@@ -5818,11 +6728,11 @@ SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
 SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
 
 /*
-** CAPI3REF: Testing Interface {F11400}
+** CAPI3REF: Testing Interface {H11400} 
 **
 ** The sqlite3_test_control() interface is used to read out internal
 ** state of SQLite and to inject faults into SQLite for testing
-** purposes.  The first parameter a operation code that determines
+** purposes.  The first parameter is an operation code that determines
 ** the number, meaning, and operation of all subsequent parameters.
 **
 ** This interface is not for use by applications.  It exists solely
@@ -5837,24 +6747,228 @@ SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*
 SQLITE_API int sqlite3_test_control(int op, ...);
 
 /*
-** CAPI3REF: Testing Interface Operation Codes {F11410}
+** CAPI3REF: Testing Interface Operation Codes {H11410} 
 **
 ** These constants are the valid operation code parameters used
 ** as the first argument to [sqlite3_test_control()].
 **
-** These parameters and their meansing are subject to change
+** These parameters and their meanings are subject to change
 ** without notice.  These values are for testing purposes only.
 ** Applications should not use any of these parameters or the
 ** [sqlite3_test_control()] interface.
 */
-#define SQLITE_TESTCTRL_FAULT_CONFIG             1
-#define SQLITE_TESTCTRL_FAULT_FAILURES           2
-#define SQLITE_TESTCTRL_FAULT_BENIGN_FAILURES    3
-#define SQLITE_TESTCTRL_FAULT_PENDING            4
-
-
-
+#define SQLITE_TESTCTRL_PRNG_SAVE                5
+#define SQLITE_TESTCTRL_PRNG_RESTORE             6
+#define SQLITE_TESTCTRL_PRNG_RESET               7
+#define SQLITE_TESTCTRL_BITVEC_TEST              8
+#define SQLITE_TESTCTRL_FAULT_INSTALL            9
+#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS     10
+
+/*
+** CAPI3REF: SQLite Runtime Status {H17200} 
+** EXPERIMENTAL
+**
+** This interface is used to retrieve runtime status information
+** about the preformance of SQLite, and optionally to reset various
+** highwater marks.  The first argument is an integer code for
+** the specific parameter to measure.  Recognized integer codes
+** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...].
+** The current value of the parameter is returned into *pCurrent.
+** The highest recorded value is returned in *pHighwater.  If the
+** resetFlag is true, then the highest record value is reset after
+** *pHighwater is written. Some parameters do not record the highest
+** value.  For those parameters
+** nothing is written into *pHighwater and the resetFlag is ignored.
+** Other parameters record only the highwater mark and not the current
+** value.  For these latter parameters nothing is written into *pCurrent.
+**
+** This routine returns SQLITE_OK on success and a non-zero
+** [error code] on failure.
+**
+** This routine is threadsafe but is not atomic.  This routine can
+** called while other threads are running the same or different SQLite
+** interfaces.  However the values returned in *pCurrent and
+** *pHighwater reflect the status of SQLite at different points in time
+** and it is possible that another thread might change the parameter
+** in between the times when *pCurrent and *pHighwater are written.
+**
+** See also: [sqlite3_db_status()]
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
+
+
+/*
+** CAPI3REF: Status Parameters {H17250} 
+** EXPERIMENTAL
+**
+** These integer constants designate various run-time status parameters
+** that can be returned by [sqlite3_status()].
+**
+** 
      
+** 
      SQLITE_STATUS_MEMORY_USED
      
+** 
      This parameter is the current amount of memory checked out
+** using [sqlite3_malloc()], either directly or indirectly.  The
+** figure includes calls made to [sqlite3_malloc()] by the application
+** and internal memory usage by the SQLite library.  Scratch memory
+** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
+** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
+** this parameter.  The amount returned is the sum of the allocation
+** sizes as reported by the xSize method in [sqlite3_mem_methods].
      
+**
+** 
      SQLITE_STATUS_MALLOC_SIZE
      
+** 
      This parameter records the largest memory allocation request
+** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
+** internal equivalents).  Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.  
+** The value written into the *pCurrent parameter is undefined.
      
+**
+** 
      SQLITE_STATUS_PAGECACHE_USED
      
+** 
      This parameter returns the number of pages used out of the
+** [pagecache memory allocator] that was configured using 
+** [SQLITE_CONFIG_PAGECACHE].  The
+** value returned is in pages, not in bytes.
      
+**
+** 
      SQLITE_STATUS_PAGECACHE_OVERFLOW
      
+** 
      This parameter returns the number of bytes of page cache
+** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE]
+** buffer and where forced to overflow to [sqlite3_malloc()].  The
+** returned value includes allocations that overflowed because they
+** where too large (they were larger than the "sz" parameter to
+** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
+** no space was left in the page cache.
      
+**
+** 
      SQLITE_STATUS_PAGECACHE_SIZE
      
+** 
      This parameter records the largest memory allocation request
+** handed to [pagecache memory allocator].  Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.  
+** The value written into the *pCurrent parameter is undefined.
      
+**
+** 
      SQLITE_STATUS_SCRATCH_USED
      
+** 
      This parameter returns the number of allocations used out of the
+** [scratch memory allocator] configured using
+** [SQLITE_CONFIG_SCRATCH].  The value returned is in allocations, not
+** in bytes.  Since a single thread may only have one scratch allocation
+** outstanding at time, this parameter also reports the number of threads
+** using scratch memory at the same time.
      
+**
+** 
      SQLITE_STATUS_SCRATCH_OVERFLOW
      
+** 
      This parameter returns the number of bytes of scratch memory
+** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH]
+** buffer and where forced to overflow to [sqlite3_malloc()].  The values
+** returned include overflows because the requested allocation was too
+** larger (that is, because the requested allocation was larger than the
+** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
+** slots were available.
+** 
      
+**
+** 
      SQLITE_STATUS_SCRATCH_SIZE
      
+** 
      This parameter records the largest memory allocation request
+** handed to [scratch memory allocator].  Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.  
+** The value written into the *pCurrent parameter is undefined.
      
+**
+** 
      SQLITE_STATUS_PARSER_STACK
      
+** 
      This parameter records the deepest parser stack.  It is only
+** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].
      
+** 
      
+**
+** New status parameters may be added from time to time.
+*/
+#define SQLITE_STATUS_MEMORY_USED          0
+#define SQLITE_STATUS_PAGECACHE_USED       1
+#define SQLITE_STATUS_PAGECACHE_OVERFLOW   2
+#define SQLITE_STATUS_SCRATCH_USED         3
+#define SQLITE_STATUS_SCRATCH_OVERFLOW     4
+#define SQLITE_STATUS_MALLOC_SIZE          5
+#define SQLITE_STATUS_PARSER_STACK         6
+#define SQLITE_STATUS_PAGECACHE_SIZE       7
+#define SQLITE_STATUS_SCRATCH_SIZE         8
+
+/*
+** CAPI3REF: Database Connection Status {H17500} 
+** EXPERIMENTAL
+**
+** This interface is used to retrieve runtime status information 
+** about a single [database connection].  The first argument is the
+** database connection object to be interrogated.  The second argument
+** is the parameter to interrogate.  Currently, the only allowed value
+** for the second parameter is [SQLITE_DBSTATUS_LOOKASIDE_USED].
+** Additional options will likely appear in future releases of SQLite.
+**
+** The current value of the requested parameter is written into *pCur
+** and the highest instantaneous value is written into *pHiwtr.  If
+** the resetFlg is true, then the highest instantaneous value is
+** reset back down to the current value.
+**
+** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
+
+/*
+** CAPI3REF: Status Parameters for database connections {H17520} 
+** EXPERIMENTAL
+**
+** Status verbs for [sqlite3_db_status()].
+**
+** 
      
+** 
      SQLITE_DBSTATUS_LOOKASIDE_USED
      
+** 
      This parameter returns the number of lookaside memory slots currently
+** checked out.
      
+** 
      
+*/
+#define SQLITE_DBSTATUS_LOOKASIDE_USED     0
+
+
+/*
+** CAPI3REF: Prepared Statement Status {H17550} 
+** EXPERIMENTAL
+**
+** Each prepared statement maintains various
+** [SQLITE_STMTSTATUS_SORT | counters] that measure the number
+** of times it has performed specific operations.  These counters can
+** be used to monitor the performance characteristics of the prepared
+** statements.  For example, if the number of table steps greatly exceeds
+** the number of table searches or result rows, that would tend to indicate
+** that the prepared statement is using a full table scan rather than
+** an index.  
+**
+** This interface is used to retrieve and reset counter values from
+** a [prepared statement].  The first argument is the prepared statement
+** object to be interrogated.  The second argument
+** is an integer code for a specific [SQLITE_STMTSTATUS_SORT | counter]
+** to be interrogated. 
+** The current value of the requested counter is returned.
+** If the resetFlg is true, then the counter is reset to zero after this
+** interface call returns.
+**
+** See also: [sqlite3_status()] and [sqlite3_db_status()].
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
 
+/*
+** CAPI3REF: Status Parameters for prepared statements {H17570} 
+** EXPERIMENTAL
+**
+** These preprocessor macros define integer codes that name counter
+** values associated with the [sqlite3_stmt_status()] interface.
+** The meanings of the various counters are as follows:
+**
+** 
      
+** 
      SQLITE_STMTSTATUS_FULLSCAN_STEP
      
+** 
      This is the number of times that SQLite has stepped forward in
+** a table as part of a full table scan.  Large numbers for this counter
+** may indicate opportunities for performance improvement through 
+** careful use of indices.
      
+**
+** 
      SQLITE_STMTSTATUS_SORT
      
+** 
      This is the number of sort operations that have occurred.
+** A non-zero value in this counter may indicate an opportunity to
+** improvement performance through careful use of indices.
      
+**
+** 
      
+*/
+#define SQLITE_STMTSTATUS_FULLSCAN_STEP     1
+#define SQLITE_STMTSTATUS_SORT              2
 
 /*
 ** Undo the hack that converts floating point types to integer for
@@ -5887,7 +7001,7 @@ SQLITE_API int sqlite3_test_control(int op, ...);
 ** This is the header file for the generic hash-table implemenation
 ** used in SQLite.
 **
-** $Id: hash.h,v 1.11 2007/09/04 14:31:47 danielk1977 Exp $
+** $Id: hash.h,v 1.12 2008/10/10 17:41:29 drh Exp $
 */
 #ifndef _SQLITE_HASH_H_
 #define _SQLITE_HASH_H_
@@ -5905,14 +7019,13 @@ typedef struct HashElem HashElem;
 ** this structure opaque.
 */
 struct Hash {
-  char keyClass;          /* SQLITE_HASH_INT, _POINTER, _STRING, _BINARY */
-  char copyKey;           /* True if copy of key made on insert */
-  int count;              /* Number of entries in this table */
-  int htsize;             /* Number of buckets in the hash table */
-  HashElem *first;        /* The first element of the array */
-  struct _ht {            /* the hash table */
-    int count;               /* Number of entries with this hash */
-    HashElem *chain;         /* Pointer to first entry with this hash */
+  unsigned int copyKey: 1;  /* True if copy of key made on insert */
+  unsigned int htsize : 31; /* Number of buckets in the hash table */
+  unsigned int count;       /* Number of entries in this table */
+  HashElem *first;          /* The first element of the array */
+  struct _ht {              /* the hash table */
+    int count;                 /* Number of entries with this hash */
+    HashElem *chain;           /* Pointer to first entry with this hash */
   } *ht;
 };
 
@@ -5929,31 +7042,9 @@ struct HashElem {
 };
 
 /*
-** There are 4 different modes of operation for a hash table:
-**
-**   SQLITE_HASH_INT         nKey is used as the key and pKey is ignored.
-**
-**   SQLITE_HASH_POINTER     pKey is used as the key and nKey is ignored.
-**
-**   SQLITE_HASH_STRING      pKey points to a string that is nKey bytes long
-**                           (including the null-terminator, if any).  Case
-**                           is ignored in comparisons.
-**
-**   SQLITE_HASH_BINARY      pKey points to binary data nKey bytes long. 
-**                           memcmp() is used to compare keys.
-**
-** A copy of the key is made for SQLITE_HASH_STRING and SQLITE_HASH_BINARY
-** if the copyKey parameter to HashInit is 1.  
-*/
-/* #define SQLITE_HASH_INT       1 // NOT USED */
-/* #define SQLITE_HASH_POINTER   2 // NOT USED */
-#define SQLITE_HASH_STRING    3
-#define SQLITE_HASH_BINARY    4
-
-/*
 ** Access routines.  To delete, insert a NULL pointer.
 */
-SQLITE_PRIVATE void sqlite3HashInit(Hash*, int keytype, int copyKey);
+SQLITE_PRIVATE void sqlite3HashInit(Hash*, int copyKey);
 SQLITE_PRIVATE void *sqlite3HashInsert(Hash*, const void *pKey, int nKey, void *pData);
 SQLITE_PRIVATE void *sqlite3HashFind(const Hash*, const void *pKey, int nKey);
 SQLITE_PRIVATE HashElem *sqlite3HashFindElem(const Hash*, const void *pKey, int nKey);
@@ -6102,39 +7193,39 @@ SQLITE_PRIVATE void sqlite3HashClear(Hash*);
 #define TK_DOT                            112
 #define TK_FROM                           113
 #define TK_JOIN                           114
-#define TK_USING                          115
-#define TK_ORDER                          116
-#define TK_BY                             117
-#define TK_GROUP                          118
-#define TK_HAVING                         119
-#define TK_LIMIT                          120
-#define TK_WHERE                          121
-#define TK_INTO                           122
-#define TK_VALUES                         123
-#define TK_INTEGER                        124
-#define TK_FLOAT                          125
-#define TK_BLOB                           126
-#define TK_REGISTER                       127
-#define TK_VARIABLE                       128
-#define TK_CASE                           129
-#define TK_WHEN                           130
-#define TK_THEN                           131
-#define TK_ELSE                           132
-#define TK_INDEX                          133
-#define TK_ALTER                          134
-#define TK_TO                             135
-#define TK_ADD                            136
-#define TK_COLUMNKW                       137
-#define TK_TO_TEXT                        138
-#define TK_TO_BLOB                        139
-#define TK_TO_NUMERIC                     140
-#define TK_TO_INT                         141
-#define TK_TO_REAL                        142
-#define TK_END_OF_FILE                    143
-#define TK_ILLEGAL                        144
-#define TK_SPACE                          145
-#define TK_UNCLOSED_STRING                146
-#define TK_COMMENT                        147
+#define TK_INDEXED                        115
+#define TK_BY                             116
+#define TK_USING                          117
+#define TK_ORDER                          118
+#define TK_GROUP                          119
+#define TK_HAVING                         120
+#define TK_LIMIT                          121
+#define TK_WHERE                          122
+#define TK_INTO                           123
+#define TK_VALUES                         124
+#define TK_INTEGER                        125
+#define TK_FLOAT                          126
+#define TK_BLOB                           127
+#define TK_REGISTER                       128
+#define TK_VARIABLE                       129
+#define TK_CASE                           130
+#define TK_WHEN                           131
+#define TK_THEN                           132
+#define TK_ELSE                           133
+#define TK_INDEX                          134
+#define TK_ALTER                          135
+#define TK_TO                             136
+#define TK_ADD                            137
+#define TK_COLUMNKW                       138
+#define TK_TO_TEXT                        139
+#define TK_TO_BLOB                        140
+#define TK_TO_NUMERIC                     141
+#define TK_TO_INT                         142
+#define TK_TO_REAL                        143
+#define TK_END_OF_FILE                    144
+#define TK_ILLEGAL                        145
+#define TK_SPACE                          146
+#define TK_UNCLOSED_STRING                147
 #define TK_FUNCTION                       148
 #define TK_COLUMN                         149
 #define TK_AGG_FUNCTION                   150
@@ -6149,8 +7240,6 @@ SQLITE_PRIVATE void sqlite3HashClear(Hash*);
 #include 
 #include 
 
-#define sqlite3_isnan(X)  ((X)!=(X))
-
 /*
 ** If compiling for a processor that lacks floating point support,
 ** substitute integer for floating-point
@@ -6206,11 +7295,11 @@ SQLITE_PRIVATE void sqlite3HashClear(Hash*);
 #endif
 
 /*
-** Provide a default value for TEMP_STORE in case it is not specified
+** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
 ** on the command-line
 */
-#ifndef TEMP_STORE
-# define TEMP_STORE 1
+#ifndef SQLITE_TEMP_STORE
+# define SQLITE_TEMP_STORE 1
 #endif
 
 /*
@@ -6282,7 +7371,7 @@ typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
 typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
 typedef INT16_TYPE i16;            /* 2-byte signed integer */
 typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
-typedef UINT8_TYPE i8;             /* 1-byte signed integer */
+typedef INT8_TYPE i8;              /* 1-byte signed integer */
 
 /*
 ** Macros to determine whether the machine is big or little endian,
@@ -6293,7 +7382,8 @@ SQLITE_PRIVATE const int sqlite3one;
 #else
 SQLITE_PRIVATE const int sqlite3one;
 #endif
-#if defined(i386) || defined(__i386__) || defined(_M_IX86)
+#if defined(i386) || defined(__i386__) || defined(_M_IX86)\
+                             || defined(__x86_64) || defined(__x86_64__)
 # define SQLITE_BIGENDIAN    0
 # define SQLITE_LITTLEENDIAN 1
 # define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
@@ -6304,6 +7394,14 @@ SQLITE_PRIVATE const int sqlite3one;
 #endif
 
 /*
+** Constants for the largest and smallest possible 64-bit signed integers.
+** These macros are designed to work correctly on both 32-bit and 64-bit
+** compilers.
+*/
+#define LARGEST_INT64  (0xffffffff|(((i64)0x7fffffff)<<32))
+#define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
+
+/*
 ** An instance of the following structure is used to store the busy-handler
 ** callback for a given sqlite handle. 
 **
@@ -6344,6 +7442,38 @@ struct BusyHandler {
 #define ArraySize(X)    (sizeof(X)/sizeof(X[0]))
 
 /*
+** The following value as a destructor means to use sqlite3DbFree().
+** This is an internal extension to SQLITE_STATIC and SQLITE_TRANSIENT.
+*/
+#define SQLITE_DYNAMIC   ((sqlite3_destructor_type)sqlite3DbFree)
+
+/*
+** When SQLITE_OMIT_WSD is defined, it means that the target platform does
+** not support Writable Static Data (WSD) such as global and static variables.
+** All variables must either be on the stack or dynamically allocated from
+** the heap.  When WSD is unsupported, the variable declarations scattered
+** throughout the SQLite code must become constants instead.  The SQLITE_WSD
+** macro is used for this purpose.  And instead of referencing the variable
+** directly, we use its constant as a key to lookup the run-time allocated
+** buffer that holds real variable.  The constant is also the initializer
+** for the run-time allocated buffer.
+**
+** In the usually case where WSD is supported, the SQLITE_WSD and GLOBAL
+** macros become no-ops and have zero performance impact.
+*/
+#ifdef SQLITE_OMIT_WSD
+  #define SQLITE_WSD const
+  #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
+  #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
+SQLITE_API   int sqlite3_wsd_init(int N, int J);
+SQLITE_API   void *sqlite3_wsd_find(void *K, int L);
+#else
+  #define SQLITE_WSD 
+  #define GLOBAL(t,v) v
+  #define sqlite3GlobalConfig sqlite3Config
+#endif
+
+/*
 ** Forward references to structures
 */
 typedef struct AggInfo AggInfo;
@@ -6357,10 +7487,13 @@ typedef struct Expr Expr;
 typedef struct ExprList ExprList;
 typedef struct FKey FKey;
 typedef struct FuncDef FuncDef;
+typedef struct FuncDefHash FuncDefHash;
 typedef struct IdList IdList;
 typedef struct Index Index;
 typedef struct KeyClass KeyClass;
 typedef struct KeyInfo KeyInfo;
+typedef struct Lookaside Lookaside;
+typedef struct LookasideSlot LookasideSlot;
 typedef struct Module Module;
 typedef struct NameContext NameContext;
 typedef struct Parse Parse;
@@ -6373,6 +7506,8 @@ typedef struct Token Token;
 typedef struct TriggerStack TriggerStack;
 typedef struct TriggerStep TriggerStep;
 typedef struct Trigger Trigger;
+typedef struct UnpackedRecord UnpackedRecord;
+typedef struct Walker Walker;
 typedef struct WhereInfo WhereInfo;
 typedef struct WhereLevel WhereLevel;
 
@@ -6398,7 +7533,7 @@ typedef struct WhereLevel WhereLevel;
 ** subsystem.  See comments in the source code for a detailed description
 ** of what each interface routine does.
 **
-** @(#) $Id: btree.h,v 1.94 2007/12/07 18:55:28 drh Exp $
+** @(#) $Id: btree.h,v 1.104 2008/10/08 17:58:49 danielk1977 Exp $
 */
 #ifndef _BTREE_H_
 #define _BTREE_H_
@@ -6461,11 +7596,6 @@ SQLITE_PRIVATE int sqlite3BtreeOpen(
 #define BTREE_READWRITE    16  /* Open for both reading and writing */
 #define BTREE_CREATE       32  /* Create the database if it does not exist */
 
-/* Additional values for the 4th argument of sqlite3BtreeOpen that
-** are not associated with PAGER_ values.
-*/
-#define BTREE_PRIVATE      64  /* Never share with other connections */
-
 SQLITE_PRIVATE int sqlite3BtreeClose(Btree*);
 SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree*,int);
 SQLITE_PRIVATE int sqlite3BtreeSetSafetyLevel(Btree*,int,int);
@@ -6516,13 +7646,27 @@ SQLITE_PRIVATE int sqlite3BtreeCursor(
   Btree*,                              /* BTree containing table to open */
   int iTable,                          /* Index of root page */
   int wrFlag,                          /* 1 for writing.  0 for read-only */
-  int(*)(void*,int,const void*,int,const void*),  /* Key comparison function */
-  void*,                               /* First argument to compare function */
-  BtCursor **ppCursor                  /* Returned cursor */
+  struct KeyInfo*,                     /* First argument to compare function */
+  BtCursor *pCursor                    /* Space to write cursor structure */
 );
+SQLITE_PRIVATE int sqlite3BtreeCursorSize(void);
 
 SQLITE_PRIVATE int sqlite3BtreeCloseCursor(BtCursor*);
-SQLITE_PRIVATE int sqlite3BtreeMoveto(BtCursor*,const void *pKey,i64 nKey,int bias,int *pRes);
+SQLITE_PRIVATE int sqlite3BtreeMoveto(
+  BtCursor*,
+  const void *pKey,
+  i64 nKey,
+  int bias,
+  int *pRes
+);
+SQLITE_PRIVATE int sqlite3BtreeMovetoUnpacked(
+  BtCursor*,
+  UnpackedRecord *pUnKey,
+  i64 intKey,
+  int bias,
+  int *pRes
+);
+SQLITE_PRIVATE int sqlite3BtreeCursorHasMoved(BtCursor*, int*);
 SQLITE_PRIVATE int sqlite3BtreeDelete(BtCursor*);
 SQLITE_PRIVATE int sqlite3BtreeInsert(BtCursor*, const void *pKey, i64 nKey,
                                   const void *pData, int nData,
@@ -6546,11 +7690,11 @@ SQLITE_PRIVATE struct Pager *sqlite3BtreePager(Btree*);
 
 SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
 SQLITE_PRIVATE void sqlite3BtreeCacheOverflow(BtCursor *);
+SQLITE_PRIVATE void sqlite3BtreeClearCursor(BtCursor *);
 
 #ifdef SQLITE_TEST
 SQLITE_PRIVATE int sqlite3BtreeCursorInfo(BtCursor*, int*, int);
 SQLITE_PRIVATE void sqlite3BtreeCursorList(Btree*);
-SQLITE_PRIVATE int sqlite3BtreePageDump(Btree*, int, int recursive);
 #endif
 
 /*
@@ -6561,24 +7705,36 @@ SQLITE_PRIVATE int sqlite3BtreePageDump(Btree*, int, int recursive);
 #if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE
 SQLITE_PRIVATE   void sqlite3BtreeEnter(Btree*);
 SQLITE_PRIVATE   void sqlite3BtreeLeave(Btree*);
+#ifndef NDEBUG
+  /* This routine is used inside assert() statements only. */
 SQLITE_PRIVATE   int sqlite3BtreeHoldsMutex(Btree*);
+#endif
 SQLITE_PRIVATE   void sqlite3BtreeEnterCursor(BtCursor*);
 SQLITE_PRIVATE   void sqlite3BtreeLeaveCursor(BtCursor*);
 SQLITE_PRIVATE   void sqlite3BtreeEnterAll(sqlite3*);
 SQLITE_PRIVATE   void sqlite3BtreeLeaveAll(sqlite3*);
+#ifndef NDEBUG
+  /* This routine is used inside assert() statements only. */
 SQLITE_PRIVATE   int sqlite3BtreeHoldsAllMutexes(sqlite3*);
+#endif
 SQLITE_PRIVATE   void sqlite3BtreeMutexArrayEnter(BtreeMutexArray*);
 SQLITE_PRIVATE   void sqlite3BtreeMutexArrayLeave(BtreeMutexArray*);
 SQLITE_PRIVATE   void sqlite3BtreeMutexArrayInsert(BtreeMutexArray*, Btree*);
 #else
 # define sqlite3BtreeEnter(X)
 # define sqlite3BtreeLeave(X)
+#ifndef NDEBUG
+  /* This routine is used inside assert() statements only. */
 # define sqlite3BtreeHoldsMutex(X) 1
+#endif
 # define sqlite3BtreeEnterCursor(X)
 # define sqlite3BtreeLeaveCursor(X)
 # define sqlite3BtreeEnterAll(X)
 # define sqlite3BtreeLeaveAll(X)
+#ifndef NDEBUG
+  /* This routine is used inside assert() statements only. */
 # define sqlite3BtreeHoldsAllMutexes(X) 1
+#endif
 # define sqlite3BtreeMutexArrayEnter(X)
 # define sqlite3BtreeMutexArrayLeave(X)
 # define sqlite3BtreeMutexArrayInsert(X,Y)
@@ -6608,7 +7764,7 @@ SQLITE_PRIVATE   void sqlite3BtreeMutexArrayInsert(BtreeMutexArray*, Btree*);
 ** or VDBE.  The VDBE implements an abstract machine that runs a
 ** simple program to access and modify the underlying database.
 **
-** $Id: vdbe.h,v 1.125 2008/01/17 17:27:31 drh Exp $
+** $Id: vdbe.h,v 1.138 2008/08/20 22:06:48 drh Exp $
 */
 #ifndef _SQLITE_VDBE_H_
 #define _SQLITE_VDBE_H_
@@ -6635,7 +7791,7 @@ typedef struct Mem Mem;
 struct VdbeOp {
   u8 opcode;          /* What operation to perform */
   signed char p4type; /* One of the P4_xxx constants for p4 */
-  u8 flags;           /* Flags for internal use */
+  u8 opflags;         /* Not currently used */
   u8 p5;              /* Fifth parameter is an unsigned character */
   int p1;             /* First operand */
   int p2;             /* Second parameter (often the jump destination) */
@@ -6652,13 +7808,14 @@ struct VdbeOp {
     Mem *pMem;             /* Used when p4type is P4_MEM */
     sqlite3_vtab *pVtab;   /* Used when p4type is P4_VTAB */
     KeyInfo *pKeyInfo;     /* Used when p4type is P4_KEYINFO */
+    int *ai;               /* Used when p4type is P4_INTARRAY */
   } p4;
 #ifdef SQLITE_DEBUG
-  char *zComment;     /* Comment to improve readability */
+  char *zComment;          /* Comment to improve readability */
 #endif
 #ifdef VDBE_PROFILE
-  int cnt;            /* Number of times this instruction was executed */
-  long long cycles;   /* Total time spend executing this instruction */
+  int cnt;                 /* Number of times this instruction was executed */
+  u64 cycles;              /* Total time spent executing this instruction */
 #endif
 };
 typedef struct VdbeOp VdbeOp;
@@ -6692,6 +7849,7 @@ typedef struct VdbeOpList VdbeOpList;
 #define P4_REAL     (-12) /* P4 is a 64-bit floating point value */
 #define P4_INT64    (-13) /* P4 is a 64-bit signed integer */
 #define P4_INT32    (-14) /* P4 is a 32-bit signed integer */
+#define P4_INTARRAY (-15) /* P4 is a vector of 32-bit integers */
 
 /* When adding a P4 argument using P4_KEYINFO, a copy of the KeyInfo structure
 ** is made.  That copy is freed when the Vdbe is finalized.  But if the
@@ -6700,7 +7858,8 @@ typedef struct VdbeOpList VdbeOpList;
 ** from a single sqliteMalloc().  But no copy is made and the calling
 ** function should *not* try to free the KeyInfo.
 */
-#define P4_KEYINFO_HANDOFF (-9)
+#define P4_KEYINFO_HANDOFF (-16)
+#define P4_KEYINFO_STATIC  (-17)
 
 /*
 ** The Vdbe.aColName array contains 5n Mem structures, where n is the 
@@ -6711,7 +7870,15 @@ typedef struct VdbeOpList VdbeOpList;
 #define COLNAME_DATABASE 2
 #define COLNAME_TABLE    3
 #define COLNAME_COLUMN   4
-#define COLNAME_N        5      /* Number of COLNAME_xxx symbols */
+#ifdef SQLITE_ENABLE_COLUMN_METADATA
+# define COLNAME_N        5      /* Number of COLNAME_xxx symbols */
+#else
+# ifdef SQLITE_OMIT_DECLTYPE
+#   define COLNAME_N      1      /* Store only the name */
+# else
+#   define COLNAME_N      2      /* Store the name and decltype */
+# endif
+#endif
 
 /*
 ** The following macro converts a relative address in the p2 field
@@ -6730,142 +7897,142 @@ typedef struct VdbeOpList VdbeOpList;
 /* Automatically generated.  Do not edit */
 /* See the mkopcodeh.awk script for details */
 #define OP_VNext                                1
-#define OP_Column                               2
-#define OP_SetCookie                            3
-#define OP_Real                               125   /* same as TK_FLOAT    */
-#define OP_Sequence                             4
-#define OP_MoveGt                               5
+#define OP_Affinity                             2
+#define OP_Column                               3
+#define OP_SetCookie                            4
+#define OP_Real                               126   /* same as TK_FLOAT    */
+#define OP_Sequence                             5
+#define OP_MoveGt                               6
 #define OP_Ge                                  72   /* same as TK_GE       */
-#define OP_RowKey                               6
-#define OP_SCopy                                7
+#define OP_RowKey                               7
+#define OP_SCopy                                8
 #define OP_Eq                                  68   /* same as TK_EQ       */
-#define OP_OpenWrite                            8
+#define OP_OpenWrite                            9
 #define OP_NotNull                             66   /* same as TK_NOTNULL  */
-#define OP_If                                   9
-#define OP_ToInt                              141   /* same as TK_TO_INT   */
+#define OP_If                                  10
+#define OP_ToInt                              142   /* same as TK_TO_INT   */
 #define OP_String8                             88   /* same as TK_STRING   */
-#define OP_VRowid                              10
-#define OP_CollSeq                             11
-#define OP_OpenRead                            12
-#define OP_Expire                              13
-#define OP_AutoCommit                          14
+#define OP_VRowid                              11
+#define OP_CollSeq                             12
+#define OP_OpenRead                            13
+#define OP_Expire                              14
+#define OP_AutoCommit                          15
 #define OP_Gt                                  69   /* same as TK_GT       */
-#define OP_IntegrityCk                         15
-#define OP_Sort                                17
-#define OP_Copy                                18
-#define OP_Trace                               19
-#define OP_Function                            20
-#define OP_IfNeg                               21
+#define OP_Pagecount                           17
+#define OP_IntegrityCk                         18
+#define OP_Sort                                19
+#define OP_Copy                                20
+#define OP_Trace                               21
+#define OP_Function                            22
+#define OP_IfNeg                               23
 #define OP_And                                 61   /* same as TK_AND      */
 #define OP_Subtract                            79   /* same as TK_MINUS    */
-#define OP_Noop                                22
-#define OP_Return                              23
+#define OP_Noop                                24
+#define OP_Return                              25
 #define OP_Remainder                           82   /* same as TK_REM      */
-#define OP_NewRowid                            24
+#define OP_NewRowid                            26
 #define OP_Multiply                            80   /* same as TK_STAR     */
-#define OP_Variable                            25
-#define OP_String                              26
-#define OP_RealAffinity                        27
-#define OP_VRename                             28
-#define OP_ParseSchema                         29
-#define OP_VOpen                               30
-#define OP_Close                               31
-#define OP_CreateIndex                         32
-#define OP_IsUnique                            33
-#define OP_NotFound                            34
-#define OP_Int64                               35
-#define OP_MustBeInt                           36
-#define OP_Halt                                37
-#define OP_Rowid                               38
-#define OP_IdxLT                               39
-#define OP_AddImm                              40
-#define OP_Statement                           41
-#define OP_RowData                             42
-#define OP_MemMax                              43
+#define OP_Variable                            27
+#define OP_String                              28
+#define OP_RealAffinity                        29
+#define OP_VRename                             30
+#define OP_ParseSchema                         31
+#define OP_VOpen                               32
+#define OP_Close                               33
+#define OP_CreateIndex                         34
+#define OP_IsUnique                            35
+#define OP_NotFound                            36
+#define OP_Int64                               37
+#define OP_MustBeInt                           38
+#define OP_Halt                                39
+#define OP_Rowid                               40
+#define OP_IdxLT                               41
+#define OP_AddImm                              42
+#define OP_Statement                           43
+#define OP_RowData                             44
+#define OP_MemMax                              45
 #define OP_Or                                  60   /* same as TK_OR       */
-#define OP_NotExists                           44
-#define OP_Gosub                               45
+#define OP_NotExists                           46
+#define OP_Gosub                               47
 #define OP_Divide                              81   /* same as TK_SLASH    */
-#define OP_Integer                             46
-#define OP_ToNumeric                          140   /* same as TK_TO_NUMERIC*/
-#define OP_Prev                                47
+#define OP_Integer                             48
+#define OP_ToNumeric                          141   /* same as TK_TO_NUMERIC*/
+#define OP_Prev                                49
 #define OP_Concat                              83   /* same as TK_CONCAT   */
 #define OP_BitAnd                              74   /* same as TK_BITAND   */
-#define OP_VColumn                             48
-#define OP_CreateTable                         49
-#define OP_Last                                50
+#define OP_VColumn                             50
+#define OP_CreateTable                         51
+#define OP_Last                                52
 #define OP_IsNull                              65   /* same as TK_ISNULL   */
-#define OP_IncrVacuum                          51
-#define OP_IdxRowid                            52
+#define OP_IncrVacuum                          53
+#define OP_IdxRowid                            54
 #define OP_ShiftRight                          77   /* same as TK_RSHIFT   */
-#define OP_ResetCount                          53
-#define OP_FifoWrite                           54
-#define OP_ContextPush                         55
-#define OP_DropTrigger                         56
-#define OP_DropIndex                           57
-#define OP_IdxGE                               58
-#define OP_IdxDelete                           59
-#define OP_Vacuum                              62
-#define OP_MoveLe                              63
-#define OP_IfNot                               64
-#define OP_DropTable                           73
-#define OP_MakeRecord                          84
-#define OP_ToBlob                             139   /* same as TK_TO_BLOB  */
-#define OP_ResultRow                           85
-#define OP_Delete                              86
-#define OP_AggFinal                            89
+#define OP_ResetCount                          55
+#define OP_FifoWrite                           56
+#define OP_ContextPush                         57
+#define OP_Yield                               58
+#define OP_DropTrigger                         59
+#define OP_DropIndex                           62
+#define OP_IdxGE                               63
+#define OP_IdxDelete                           64
+#define OP_Vacuum                              73
+#define OP_MoveLe                              84
+#define OP_IfNot                               85
+#define OP_DropTable                           86
+#define OP_MakeRecord                          89
+#define OP_ToBlob                             140   /* same as TK_TO_BLOB  */
+#define OP_ResultRow                           90
+#define OP_Delete                              91
+#define OP_AggFinal                            92
+#define OP_Compare                             93
 #define OP_ShiftLeft                           76   /* same as TK_LSHIFT   */
-#define OP_Goto                                90
-#define OP_TableLock                           91
-#define OP_FifoRead                            92
-#define OP_Clear                               93
-#define OP_MoveLt                              94
+#define OP_Goto                                94
+#define OP_TableLock                           95
+#define OP_FifoRead                            96
+#define OP_Clear                               97
+#define OP_MoveLt                              98
 #define OP_Le                                  70   /* same as TK_LE       */
-#define OP_VerifyCookie                        95
-#define OP_AggStep                             96
-#define OP_ToText                             138   /* same as TK_TO_TEXT  */
+#define OP_VerifyCookie                        99
+#define OP_AggStep                            100
+#define OP_ToText                             139   /* same as TK_TO_TEXT  */
 #define OP_Not                                 16   /* same as TK_NOT      */
-#define OP_ToReal                             142   /* same as TK_TO_REAL  */
-#define OP_SetNumColumns                       97
-#define OP_Transaction                         98
-#define OP_VFilter                             99
+#define OP_ToReal                             143   /* same as TK_TO_REAL  */
+#define OP_SetNumColumns                      101
+#define OP_Transaction                        102
+#define OP_VFilter                            103
 #define OP_Ne                                  67   /* same as TK_NE       */
-#define OP_VDestroy                           100
-#define OP_ContextPop                         101
+#define OP_VDestroy                           104
+#define OP_ContextPop                         105
 #define OP_BitOr                               75   /* same as TK_BITOR    */
-#define OP_Next                               102
-#define OP_IdxInsert                          103
+#define OP_Next                               106
+#define OP_IdxInsert                          107
 #define OP_Lt                                  71   /* same as TK_LT       */
-#define OP_Insert                             104
-#define OP_Destroy                            105
-#define OP_ReadCookie                         106
-#define OP_ForceInt                           107
-#define OP_LoadAnalysis                       108
-#define OP_Explain                            109
-#define OP_OpenPseudo                         110
-#define OP_OpenEphemeral                      111
-#define OP_Null                               112
-#define OP_Move                               113
-#define OP_Blob                               114
+#define OP_Insert                             108
+#define OP_Destroy                            109
+#define OP_ReadCookie                         110
+#define OP_ForceInt                           111
+#define OP_LoadAnalysis                       112
+#define OP_Explain                            113
+#define OP_OpenPseudo                         114
+#define OP_OpenEphemeral                      115
+#define OP_Null                               116
+#define OP_Move                               117
+#define OP_Blob                               118
 #define OP_Add                                 78   /* same as TK_PLUS     */
-#define OP_Rewind                             115
-#define OP_MoveGe                             116
-#define OP_VBegin                             117
-#define OP_VUpdate                            118
-#define OP_IfZero                             119
+#define OP_Rewind                             119
+#define OP_MoveGe                             120
+#define OP_VBegin                             121
+#define OP_VUpdate                            122
+#define OP_IfZero                             123
 #define OP_BitNot                              87   /* same as TK_BITNOT   */
-#define OP_VCreate                            120
-#define OP_Found                              121
-#define OP_IfPos                              122
-#define OP_NullRow                            123
+#define OP_VCreate                            124
+#define OP_Found                              125
+#define OP_IfPos                              127
+#define OP_NullRow                            128
+#define OP_Jump                               129
+#define OP_Permutation                        130
 
 /* The following opcode values are never used */
-#define OP_NotUsed_124                        124
-#define OP_NotUsed_126                        126
-#define OP_NotUsed_127                        127
-#define OP_NotUsed_128                        128
-#define OP_NotUsed_129                        129
-#define OP_NotUsed_130                        130
 #define OP_NotUsed_131                        131
 #define OP_NotUsed_132                        132
 #define OP_NotUsed_133                        133
@@ -6873,6 +8040,7 @@ typedef struct VdbeOpList VdbeOpList;
 #define OP_NotUsed_135                        135
 #define OP_NotUsed_136                        136
 #define OP_NotUsed_137                        137
+#define OP_NotUsed_138                        138
 
 
 /* Properties such as "out2" or "jump" that are specified in
@@ -6886,24 +8054,25 @@ typedef struct VdbeOpList VdbeOpList;
 #define OPFLG_IN3             0x0010  /* in3:   P3 is an input */
 #define OPFLG_OUT3            0x0020  /* out3:  P3 is an output */
 #define OPFLG_INITIALIZER {\
-/*   0 */ 0x00, 0x01, 0x00, 0x10, 0x02, 0x11, 0x00, 0x00,\
-/*   8 */ 0x00, 0x05, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00,\
-/*  16 */ 0x04, 0x01, 0x00, 0x00, 0x00, 0x05, 0x00, 0x00,\
-/*  24 */ 0x02, 0x02, 0x02, 0x04, 0x00, 0x00, 0x00, 0x00,\
-/*  32 */ 0x02, 0x11, 0x11, 0x02, 0x05, 0x00, 0x02, 0x11,\
-/*  40 */ 0x04, 0x00, 0x00, 0x0c, 0x11, 0x01, 0x02, 0x01,\
-/*  48 */ 0x00, 0x02, 0x01, 0x01, 0x02, 0x00, 0x04, 0x00,\
-/*  56 */ 0x00, 0x00, 0x11, 0x08, 0x2c, 0x2c, 0x00, 0x11,\
-/*  64 */ 0x05, 0x05, 0x05, 0x15, 0x15, 0x15, 0x15, 0x15,\
+/*   0 */ 0x00, 0x01, 0x00, 0x00, 0x10, 0x02, 0x11, 0x00,\
+/*   8 */ 0x00, 0x00, 0x05, 0x02, 0x00, 0x00, 0x00, 0x00,\
+/*  16 */ 0x04, 0x02, 0x00, 0x01, 0x00, 0x00, 0x00, 0x05,\
+/*  24 */ 0x00, 0x04, 0x02, 0x02, 0x02, 0x04, 0x00, 0x00,\
+/*  32 */ 0x00, 0x00, 0x02, 0x11, 0x11, 0x02, 0x05, 0x00,\
+/*  40 */ 0x02, 0x11, 0x04, 0x00, 0x00, 0x0c, 0x11, 0x01,\
+/*  48 */ 0x02, 0x01, 0x00, 0x02, 0x01, 0x01, 0x02, 0x00,\
+/*  56 */ 0x04, 0x00, 0x00, 0x00, 0x2c, 0x2c, 0x00, 0x11,\
+/*  64 */ 0x00, 0x05, 0x05, 0x15, 0x15, 0x15, 0x15, 0x15,\
 /*  72 */ 0x15, 0x00, 0x2c, 0x2c, 0x2c, 0x2c, 0x2c, 0x2c,\
-/*  80 */ 0x2c, 0x2c, 0x2c, 0x2c, 0x00, 0x00, 0x00, 0x04,\
-/*  88 */ 0x02, 0x00, 0x01, 0x00, 0x01, 0x00, 0x11, 0x00,\
-/*  96 */ 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x01, 0x08,\
-/* 104 */ 0x00, 0x02, 0x02, 0x05, 0x00, 0x00, 0x00, 0x00,\
-/* 112 */ 0x02, 0x00, 0x02, 0x01, 0x11, 0x00, 0x00, 0x05,\
-/* 120 */ 0x00, 0x11, 0x05, 0x00, 0x00, 0x02, 0x00, 0x00,\
-/* 128 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
-/* 136 */ 0x00, 0x00, 0x04, 0x04, 0x04, 0x04, 0x04,}
+/*  80 */ 0x2c, 0x2c, 0x2c, 0x2c, 0x11, 0x05, 0x00, 0x04,\
+/*  88 */ 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00,\
+/*  96 */ 0x01, 0x00, 0x11, 0x00, 0x00, 0x00, 0x00, 0x01,\
+/* 104 */ 0x00, 0x00, 0x01, 0x08, 0x00, 0x02, 0x02, 0x05,\
+/* 112 */ 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x02, 0x01,\
+/* 120 */ 0x11, 0x00, 0x00, 0x05, 0x00, 0x11, 0x02, 0x05,\
+/* 128 */ 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
+/* 136 */ 0x00, 0x00, 0x00, 0x04, 0x04, 0x04, 0x04, 0x04,\
+}
 
 /************** End of opcodes.h *********************************************/
 /************** Continuing where we left off in vdbe.h ***********************/
@@ -6946,11 +8115,23 @@ SQLITE_PRIVATE sqlite3 *sqlite3VdbeDb(Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeSetSql(Vdbe*, const char *z, int n);
 SQLITE_PRIVATE void sqlite3VdbeSwap(Vdbe*,Vdbe*);
 
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+SQLITE_PRIVATE int sqlite3VdbeReleaseMemory(int);
+#endif
+SQLITE_PRIVATE UnpackedRecord *sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,
+                                        UnpackedRecord*,int);
+SQLITE_PRIVATE void sqlite3VdbeDeleteUnpackedRecord(UnpackedRecord*);
+SQLITE_PRIVATE int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);
+
+
 #ifndef NDEBUG
 SQLITE_PRIVATE   void sqlite3VdbeComment(Vdbe*, const char*, ...);
 # define VdbeComment(X)  sqlite3VdbeComment X
+SQLITE_PRIVATE   void sqlite3VdbeNoopComment(Vdbe*, const char*, ...);
+# define VdbeNoopComment(X)  sqlite3VdbeNoopComment X
 #else
 # define VdbeComment(X)
+# define VdbeNoopComment(X)
 #endif
 
 #endif
@@ -6974,17 +8155,25 @@ SQLITE_PRIVATE   void sqlite3VdbeComment(Vdbe*, const char*, ...);
 ** subsystem.  The page cache subsystem reads and writes a file a page
 ** at a time and provides a journal for rollback.
 **
-** @(#) $Id: pager.h,v 1.69 2008/02/02 20:47:38 drh Exp $
+** @(#) $Id: pager.h,v 1.85 2008/09/29 11:49:48 danielk1977 Exp $
 */
 
 #ifndef _PAGER_H_
 #define _PAGER_H_
 
 /*
+** If defined as non-zero, auto-vacuum is enabled by default. Otherwise
+** it must be turned on for each database using "PRAGMA auto_vacuum = 1".
+*/
+#ifndef SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT
+  #define SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT -1
+#endif
+
+/*
 ** The type used to represent a page number.  The first page in a file
 ** is called page 1.  0 is used to represent "not a page".
 */
-typedef unsigned int Pgno;
+typedef u32 Pgno;
 
 /*
 ** Each open file is managed by a separate instance of the "Pager" structure.
@@ -7012,13 +8201,21 @@ typedef struct PgHdr DbPage;
 #define PAGER_LOCKINGMODE_EXCLUSIVE   1
 
 /*
+** Valid values for the second argument to sqlite3PagerJournalMode().
+*/
+#define PAGER_JOURNALMODE_QUERY      -1
+#define PAGER_JOURNALMODE_DELETE      0   /* Commit by deleting journal file */
+#define PAGER_JOURNALMODE_PERSIST     1   /* Commit by zeroing journal header */
+#define PAGER_JOURNALMODE_OFF         2   /* Journal omitted.  */
+#define PAGER_JOURNALMODE_TRUNCATE    3   /* Commit by truncating journal */
+
+/*
 ** See source code comments for a detailed description of the following
 ** routines:
 */
 SQLITE_PRIVATE int sqlite3PagerOpen(sqlite3_vfs *, Pager **ppPager, const char*, int,int,int);
 SQLITE_PRIVATE void sqlite3PagerSetBusyhandler(Pager*, BusyHandler *pBusyHandler);
-SQLITE_PRIVATE void sqlite3PagerSetDestructor(Pager*, void(*)(DbPage*,int));
-SQLITE_PRIVATE void sqlite3PagerSetReiniter(Pager*, void(*)(DbPage*,int));
+SQLITE_PRIVATE void sqlite3PagerSetReiniter(Pager*, void(*)(DbPage*));
 SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager*, u16*);
 SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager*, int);
 SQLITE_PRIVATE int sqlite3PagerReadFileheader(Pager*, int, unsigned char*);
@@ -7027,14 +8224,14 @@ SQLITE_PRIVATE int sqlite3PagerClose(Pager *pPager);
 SQLITE_PRIVATE int sqlite3PagerAcquire(Pager *pPager, Pgno pgno, DbPage **ppPage, int clrFlag);
 #define sqlite3PagerGet(A,B,C) sqlite3PagerAcquire(A,B,C,0)
 SQLITE_PRIVATE DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno);
+SQLITE_PRIVATE int sqlite3PagerPageRefcount(DbPage*);
 SQLITE_PRIVATE int sqlite3PagerRef(DbPage*);
 SQLITE_PRIVATE int sqlite3PagerUnref(DbPage*);
 SQLITE_PRIVATE int sqlite3PagerWrite(DbPage*);
-SQLITE_PRIVATE int sqlite3PagerOverwrite(Pager *pPager, Pgno pgno, void*);
-SQLITE_PRIVATE int sqlite3PagerPagecount(Pager*);
+SQLITE_PRIVATE int sqlite3PagerPagecount(Pager*, int*);
 SQLITE_PRIVATE int sqlite3PagerTruncate(Pager*,Pgno);
 SQLITE_PRIVATE int sqlite3PagerBegin(DbPage*, int exFlag);
-SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, Pgno);
+SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, Pgno, int);
 SQLITE_PRIVATE int sqlite3PagerCommitPhaseTwo(Pager*);
 SQLITE_PRIVATE int sqlite3PagerRollback(Pager*);
 SQLITE_PRIVATE int sqlite3PagerIsreadonly(Pager*);
@@ -7042,7 +8239,7 @@ SQLITE_PRIVATE int sqlite3PagerStmtBegin(Pager*);
 SQLITE_PRIVATE int sqlite3PagerStmtCommit(Pager*);
 SQLITE_PRIVATE int sqlite3PagerStmtRollback(Pager*);
 SQLITE_PRIVATE void sqlite3PagerDontRollback(DbPage*);
-SQLITE_PRIVATE void sqlite3PagerDontWrite(DbPage*);
+SQLITE_PRIVATE int sqlite3PagerDontWrite(DbPage*);
 SQLITE_PRIVATE int sqlite3PagerRefcount(Pager*);
 SQLITE_PRIVATE void sqlite3PagerSetSafetyLevel(Pager*,int,int);
 SQLITE_PRIVATE const char *sqlite3PagerFilename(Pager*);
@@ -7051,15 +8248,14 @@ SQLITE_PRIVATE sqlite3_file *sqlite3PagerFile(Pager*);
 SQLITE_PRIVATE const char *sqlite3PagerDirname(Pager*);
 SQLITE_PRIVATE const char *sqlite3PagerJournalname(Pager*);
 SQLITE_PRIVATE int sqlite3PagerNosync(Pager*);
-SQLITE_PRIVATE int sqlite3PagerMovepage(Pager*,DbPage*,Pgno);
+SQLITE_PRIVATE int sqlite3PagerMovepage(Pager*,DbPage*,Pgno,int);
 SQLITE_PRIVATE void *sqlite3PagerGetData(DbPage *); 
 SQLITE_PRIVATE void *sqlite3PagerGetExtra(DbPage *); 
 SQLITE_PRIVATE int sqlite3PagerLockingMode(Pager *, int);
+SQLITE_PRIVATE int sqlite3PagerJournalMode(Pager *, int);
+SQLITE_PRIVATE i64 sqlite3PagerJournalSizeLimit(Pager *, i64);
 SQLITE_PRIVATE void *sqlite3PagerTempSpace(Pager*);
-
-#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) && !defined(SQLITE_OMIT_DISKIO)
-SQLITE_PRIVATE   int sqlite3PagerReleaseMemory(int);
-#endif
+SQLITE_PRIVATE int sqlite3PagerSync(Pager *pPager);
 
 #ifdef SQLITE_HAS_CODEC
 SQLITE_PRIVATE   void sqlite3PagerSetCodec(Pager*,void*(*)(void*,void*,Pgno,int),void*);
@@ -7073,6 +8269,7 @@ SQLITE_PRIVATE   int sqlite3PagerIswriteable(DbPage*);
 #ifdef SQLITE_TEST
 SQLITE_PRIVATE   int *sqlite3PagerStats(Pager*);
 SQLITE_PRIVATE   void sqlite3PagerRefdump(Pager*);
+SQLITE_PRIVATE   int sqlite3PagerIsMemdb(Pager*);
 #endif
 
 #ifdef SQLITE_TEST
@@ -7087,6 +8284,187 @@ void enable_simulated_io_errors(void);
 
 /************** End of pager.h ***********************************************/
 /************** Continuing where we left off in sqliteInt.h ******************/
+/************** Include pcache.h in the middle of sqliteInt.h ****************/
+/************** Begin file pcache.h ******************************************/
+/*
+** 2008 August 05
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This header file defines the interface that the sqlite page cache
+** subsystem. 
+**
+** @(#) $Id: pcache.h,v 1.13 2008/10/11 17:42:29 drh Exp $
+*/
+
+#ifndef _PCACHE_H_
+
+typedef struct PgHdr PgHdr;
+typedef struct PCache PCache;
+
+/*
+** Every page in the cache is controlled by an instance of the following
+** structure.
+*/
+struct PgHdr {
+  void *pData;                   /* Content of this page */
+  void *pExtra;                  /* Extra content */
+  PgHdr *pDirty;                 /* Transient list of dirty pages */
+  Pgno pgno;                     /* Page number for this page */
+  Pager *pPager;                 /* The pager this page is part of */
+#ifdef SQLITE_CHECK_PAGES
+  u32 pageHash;                  /* Hash of page content */
+#endif
+  u16 flags;                     /* PGHDR flags defined below */
+  /**********************************************************************
+  ** Elements above are public.  All that follows is private to pcache.c
+  ** and should not be accessed by other modules.
+  */
+  i16 nRef;                      /* Number of users of this page */
+  PCache *pCache;                /* Cache that owns this page */
+  void *apSave[2];               /* Journal entries for in-memory databases */
+  /**********************************************************************
+  ** Elements above are accessible at any time by the owner of the cache
+  ** without the need for a mutex.  The elements that follow can only be
+  ** accessed while holding the SQLITE_MUTEX_STATIC_LRU mutex.
+  */
+  PgHdr *pNextHash, *pPrevHash;  /* Hash collision chain for PgHdr.pgno */
+  PgHdr *pNext, *pPrev;          /* List of clean or dirty pages */
+  PgHdr *pNextLru, *pPrevLru;    /* Part of global LRU list */
+};
+
+/* Bit values for PgHdr.flags */
+#define PGHDR_IN_JOURNAL        0x001  /* Page is in rollback journal */
+#define PGHDR_DIRTY             0x002  /* Page has changed */
+#define PGHDR_NEED_SYNC         0x004  /* Fsync the rollback journal before
+                                       ** writing this page to the database */
+#define PGHDR_NEED_READ         0x008  /* Content is unread */
+#define PGHDR_REUSE_UNLIKELY    0x010  /* A hint that reuse is unlikely */
+#define PGHDR_DONT_WRITE        0x020  /* Do not write content to disk */
+
+/* Initialize and shutdown the page cache subsystem */
+SQLITE_PRIVATE int sqlite3PcacheInitialize(void);
+SQLITE_PRIVATE void sqlite3PcacheShutdown(void);
+
+/* Page cache buffer management:
+** These routines implement SQLITE_CONFIG_PAGECACHE.
+*/
+SQLITE_PRIVATE void sqlite3PCacheBufferSetup(void *, int sz, int n);
+SQLITE_PRIVATE void *sqlite3PCacheMalloc(int sz);
+SQLITE_PRIVATE void sqlite3PCacheFree(void*);
+
+/* Create a new pager cache.
+** Under memory stress, invoke xStress to try to make pages clean.
+** Only clean and unpinned pages can be reclaimed.
+*/
+SQLITE_PRIVATE void sqlite3PcacheOpen(
+  int szPage,                    /* Size of every page */
+  int szExtra,                   /* Extra space associated with each page */
+  int bPurgeable,                /* True if pages are on backing store */
+  int (*xStress)(void*, PgHdr*), /* Call to try to make pages clean */
+  void *pStress,                 /* Argument to xStress */
+  PCache *pToInit                /* Preallocated space for the PCache */
+);
+
+/* Modify the page-size after the cache has been created. */
+SQLITE_PRIVATE void sqlite3PcacheSetPageSize(PCache *, int);
+
+/* Return the size in bytes of a PCache object.  Used to preallocate
+** storage space.
+*/
+SQLITE_PRIVATE int sqlite3PcacheSize(void);
+
+/* One release per successful fetch.  Page is pinned until released.
+** Reference counted. 
+*/
+SQLITE_PRIVATE int sqlite3PcacheFetch(PCache*, Pgno, int createFlag, PgHdr**);
+SQLITE_PRIVATE void sqlite3PcacheRelease(PgHdr*);
+
+SQLITE_PRIVATE void sqlite3PcacheDrop(PgHdr*);         /* Remove page from cache */
+SQLITE_PRIVATE void sqlite3PcacheMakeDirty(PgHdr*);    /* Make sure page is marked dirty */
+SQLITE_PRIVATE void sqlite3PcacheMakeClean(PgHdr*);    /* Mark a single page as clean */
+SQLITE_PRIVATE void sqlite3PcacheCleanAll(PCache*);    /* Mark all dirty list pages as clean */
+
+/* Change a page number.  Used by incr-vacuum. */
+SQLITE_PRIVATE void sqlite3PcacheMove(PgHdr*, Pgno);
+
+/* Remove all pages with pgno>x.  Reset the cache if x==0 */
+SQLITE_PRIVATE void sqlite3PcacheTruncate(PCache*, Pgno x);
+
+/* Routines used to implement transactions on memory-only databases. */
+SQLITE_PRIVATE int sqlite3PcachePreserve(PgHdr*, int);    /* Preserve current page content */
+SQLITE_PRIVATE void sqlite3PcacheCommit(PCache*, int);    /* Drop preserved copy */
+SQLITE_PRIVATE void sqlite3PcacheRollback(PCache*, int, void (*xReiniter)(PgHdr*));
+
+/* Get a list of all dirty pages in the cache, sorted by page number */
+SQLITE_PRIVATE PgHdr *sqlite3PcacheDirtyList(PCache*);
+
+/* Reset and close the cache object */
+SQLITE_PRIVATE void sqlite3PcacheClose(PCache*);
+
+/* Clear flags from pages of the page cache */
+SQLITE_PRIVATE void sqlite3PcacheClearFlags(PCache*, int mask);
+
+/* Assert flags settings on all pages.  Debugging only */
+#ifndef NDEBUG
+SQLITE_PRIVATE   void sqlite3PcacheAssertFlags(PCache*, int trueMask, int falseMask);
+#else
+# define sqlite3PcacheAssertFlags(A,B,C)
+#endif
+
+/* Return true if the number of dirty pages is 0 or 1 */
+SQLITE_PRIVATE int sqlite3PcacheZeroOrOneDirtyPages(PCache*);
+
+/* Discard the contents of the cache */
+SQLITE_PRIVATE int sqlite3PcacheClear(PCache*);
+
+/* Return the total number of outstanding page references */
+SQLITE_PRIVATE int sqlite3PcacheRefCount(PCache*);
+
+/* Increment the reference count of an existing page */
+SQLITE_PRIVATE void sqlite3PcacheRef(PgHdr*);
+
+SQLITE_PRIVATE int sqlite3PcachePageRefcount(PgHdr*);
+
+/* Return the total number of pages stored in the cache */
+SQLITE_PRIVATE int sqlite3PcachePagecount(PCache*);
+
+#ifdef SQLITE_CHECK_PAGES
+/* Iterate through all pages currently stored in the cache. This interface
+** is only available if SQLITE_CHECK_PAGES is defined when the library is 
+** built.
+*/
+SQLITE_PRIVATE void sqlite3PcacheIterate(PCache *pCache, void (*xIter)(PgHdr *));
+#endif
+
+/* Set and get the suggested cache-size for the specified pager-cache.
+**
+** If no global maximum is configured, then the system attempts to limit
+** the total number of pages cached by purgeable pager-caches to the sum
+** of the suggested cache-sizes.
+*/
+SQLITE_PRIVATE int sqlite3PcacheGetCachesize(PCache *);
+SQLITE_PRIVATE void sqlite3PcacheSetCachesize(PCache *, int);
+
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+/* Try to return memory used by the pcache module to the main memory heap */
+SQLITE_PRIVATE int sqlite3PcacheReleaseMemory(int);
+#endif
+
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE void sqlite3PcacheStats(int*,int*,int*,int*);
+#endif
+
+#endif /* _PCACHE_H_ */
+
+/************** End of pcache.h **********************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
 
 /************** Include os.h in the middle of sqliteInt.h ********************/
 /************** Begin file os.h **********************************************/
@@ -7108,6 +8486,8 @@ void enable_simulated_io_errors(void);
 **
 ** This header file is #include-ed by sqliteInt.h and thus ends up
 ** being included by every source file.
+**
+** $Id: os.h,v 1.105 2008/06/26 10:41:19 danielk1977 Exp $
 */
 #ifndef _SQLITE_OS_H_
 #define _SQLITE_OS_H_
@@ -7115,56 +8495,66 @@ void enable_simulated_io_errors(void);
 /*
 ** Figure out if we are dealing with Unix, Windows, or some other
 ** operating system.  After the following block of preprocess macros,
-** all of OS_UNIX, OS_WIN, OS_OS2, and OS_OTHER will defined to either
-** 1 or 0.  One of the four will be 1.  The other three will be 0.
-*/
-#if defined(OS_OTHER)
-# if OS_OTHER==1
-#   undef OS_UNIX
-#   define OS_UNIX 0
-#   undef OS_WIN
-#   define OS_WIN 0
-#   undef OS_OS2
-#   define OS_OS2 0
+** all of SQLITE_OS_UNIX, SQLITE_OS_WIN, SQLITE_OS_OS2, and SQLITE_OS_OTHER 
+** will defined to either 1 or 0.  One of the four will be 1.  The other 
+** three will be 0.
+*/
+#if defined(SQLITE_OS_OTHER)
+# if SQLITE_OS_OTHER==1
+#   undef SQLITE_OS_UNIX
+#   define SQLITE_OS_UNIX 0
+#   undef SQLITE_OS_WIN
+#   define SQLITE_OS_WIN 0
+#   undef SQLITE_OS_OS2
+#   define SQLITE_OS_OS2 0
 # else
-#   undef OS_OTHER
+#   undef SQLITE_OS_OTHER
 # endif
 #endif
-#if !defined(OS_UNIX) && !defined(OS_OTHER)
-# define OS_OTHER 0
-# ifndef OS_WIN
+#if !defined(SQLITE_OS_UNIX) && !defined(SQLITE_OS_OTHER)
+# define SQLITE_OS_OTHER 0
+# ifndef SQLITE_OS_WIN
 #   if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || defined(__MINGW32__) || defined(__BORLANDC__)
-#     define OS_WIN 1
-#     define OS_UNIX 0
-#     define OS_OS2 0
+#     define SQLITE_OS_WIN 1
+#     define SQLITE_OS_UNIX 0
+#     define SQLITE_OS_OS2 0
 #   elif defined(__EMX__) || defined(_OS2) || defined(OS2) || defined(_OS2_) || defined(__OS2__)
-#     define OS_WIN 0
-#     define OS_UNIX 0
-#     define OS_OS2 1
+#     define SQLITE_OS_WIN 0
+#     define SQLITE_OS_UNIX 0
+#     define SQLITE_OS_OS2 1
 #   else
-#     define OS_WIN 0
-#     define OS_UNIX 1
-#     define OS_OS2 0
+#     define SQLITE_OS_WIN 0
+#     define SQLITE_OS_UNIX 1
+#     define SQLITE_OS_OS2 0
 #  endif
 # else
-#  define OS_UNIX 0
-#  define OS_OS2 0
+#  define SQLITE_OS_UNIX 0
+#  define SQLITE_OS_OS2 0
 # endif
 #else
-# ifndef OS_WIN
-#  define OS_WIN 0
+# ifndef SQLITE_OS_WIN
+#  define SQLITE_OS_WIN 0
 # endif
 #endif
 
+/*
+** Determine if we are dealing with WindowsCE - which has a much
+** reduced API.
+*/
+#if defined(_WIN32_WCE)
+# define SQLITE_OS_WINCE 1
+#else
+# define SQLITE_OS_WINCE 0
+#endif
 
 
 /*
 ** Define the maximum size of a temporary filename
 */
-#if OS_WIN
+#if SQLITE_OS_WIN
 # include 
 # define SQLITE_TEMPNAME_SIZE (MAX_PATH+50)
-#elif OS_OS2
+#elif SQLITE_OS_OS2
 # if (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ >= 3) && defined(OS2_HIGH_MEMORY)
 #  include  /* has to be included before os2.h for linking to work */
 # endif
@@ -7176,6 +8566,7 @@ void enable_simulated_io_errors(void);
 # define INCL_DOSMODULEMGR
 # define INCL_DOSSEMAPHORES
 # include 
+# include 
 # define SQLITE_TEMPNAME_SIZE (CCHMAXPATHCOMP)
 #else
 # define SQLITE_TEMPNAME_SIZE 200
@@ -7322,7 +8713,7 @@ SQLITE_PRIVATE int sqlite3OsSync(sqlite3_file*, int);
 SQLITE_PRIVATE int sqlite3OsFileSize(sqlite3_file*, i64 *pSize);
 SQLITE_PRIVATE int sqlite3OsLock(sqlite3_file*, int);
 SQLITE_PRIVATE int sqlite3OsUnlock(sqlite3_file*, int);
-SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id);
+SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id, int *pResOut);
 SQLITE_PRIVATE int sqlite3OsFileControl(sqlite3_file*,int,void*);
 SQLITE_PRIVATE int sqlite3OsSectorSize(sqlite3_file *id);
 SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id);
@@ -7332,13 +8723,14 @@ SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id);
 */
 SQLITE_PRIVATE int sqlite3OsOpen(sqlite3_vfs *, const char *, sqlite3_file*, int, int *);
 SQLITE_PRIVATE int sqlite3OsDelete(sqlite3_vfs *, const char *, int);
-SQLITE_PRIVATE int sqlite3OsAccess(sqlite3_vfs *, const char *, int);
-SQLITE_PRIVATE int sqlite3OsGetTempname(sqlite3_vfs *, int, char *);
+SQLITE_PRIVATE int sqlite3OsAccess(sqlite3_vfs *, const char *, int, int *pResOut);
 SQLITE_PRIVATE int sqlite3OsFullPathname(sqlite3_vfs *, const char *, int, char *);
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
 SQLITE_PRIVATE void *sqlite3OsDlOpen(sqlite3_vfs *, const char *);
 SQLITE_PRIVATE void sqlite3OsDlError(sqlite3_vfs *, int, char *);
 SQLITE_PRIVATE void *sqlite3OsDlSym(sqlite3_vfs *, void *, const char *);
 SQLITE_PRIVATE void sqlite3OsDlClose(sqlite3_vfs *, void *);
+#endif /* SQLITE_OMIT_LOAD_EXTENSION */
 SQLITE_PRIVATE int sqlite3OsRandomness(sqlite3_vfs *, int, char *);
 SQLITE_PRIVATE int sqlite3OsSleep(sqlite3_vfs *, int);
 SQLITE_PRIVATE int sqlite3OsCurrentTime(sqlite3_vfs *, double*);
@@ -7350,20 +8742,6 @@ SQLITE_PRIVATE int sqlite3OsCurrentTime(sqlite3_vfs *, double*);
 SQLITE_PRIVATE int sqlite3OsOpenMalloc(sqlite3_vfs *, const char *, sqlite3_file **, int,int*);
 SQLITE_PRIVATE int sqlite3OsCloseFree(sqlite3_file *);
 
-/*
-** Each OS-specific backend defines an instance of the following
-** structure for returning a pointer to its sqlite3_vfs.  If OS_OTHER
-** is defined (meaning that the application-defined OS interface layer
-** is used) then there is no default VFS.   The application must
-** register one or more VFS structures using sqlite3_vfs_register()
-** before attempting to use SQLite.
-*/
-#if OS_UNIX || OS_WIN || OS_OS2
-SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void);
-#else
-# define sqlite3OsDefaultVfs(X) 0
-#endif
-
 #endif /* _SQLITE_OS_H_ */
 
 /************** End of os.h **************************************************/
@@ -7391,28 +8769,21 @@ SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void);
 ** Source files should #include the sqliteInt.h file and let that file
 ** include this one indirectly.
 **
-** $Id: mutex.h,v 1.2 2007/08/30 14:10:30 drh Exp $
+** $Id: mutex.h,v 1.9 2008/10/07 15:25:48 drh Exp $
 */
 
 
-#ifdef SQLITE_MUTEX_APPDEF
-/*
-** If SQLITE_MUTEX_APPDEF is defined, then this whole module is
-** omitted and equivalent functionality must be provided by the
-** application that links against the SQLite library.
-*/
-#else
 /*
 ** Figure out what version of the code to use.  The choices are
 **
-**   SQLITE_MUTEX_NOOP         For single-threaded applications that
-**                             do not desire error checking.
+**   SQLITE_MUTEX_OMIT         No mutex logic.  Not even stubs.  The
+**                             mutexes implemention cannot be overridden
+**                             at start-time.
 **
-**   SQLITE_MUTEX_NOOP_DEBUG   For single-threaded applications with
-**                             error checking to help verify that mutexes
-**                             are being used correctly even though they
-**                             are not needed.  Used when SQLITE_DEBUG is
-**                             defined on single-threaded builds.
+**   SQLITE_MUTEX_NOOP         For single-threaded applications.  No
+**                             mutual exclusion is provided.  But this
+**                             implementation can be overridden at
+**                             start-time.
 **
 **   SQLITE_MUTEX_PTHREADS     For multi-threaded applications on Unix.
 **
@@ -7420,25 +8791,22 @@ SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void);
 **
 **   SQLITE_MUTEX_OS2          For multi-threaded applications on OS/2.
 */
-#define SQLITE_MUTEX_NOOP 1   /* The default */
-#if defined(SQLITE_DEBUG) && !SQLITE_THREADSAFE
-# undef SQLITE_MUTEX_NOOP
-# define SQLITE_MUTEX_NOOP_DEBUG
-#endif
-#if defined(SQLITE_MUTEX_NOOP) && SQLITE_THREADSAFE && OS_UNIX
-# undef SQLITE_MUTEX_NOOP
-# define SQLITE_MUTEX_PTHREADS
-#endif
-#if defined(SQLITE_MUTEX_NOOP) && SQLITE_THREADSAFE && OS_WIN
-# undef SQLITE_MUTEX_NOOP
-# define SQLITE_MUTEX_W32
-#endif
-#if defined(SQLITE_MUTEX_NOOP) && SQLITE_THREADSAFE && OS_OS2
-# undef SQLITE_MUTEX_NOOP
-# define SQLITE_MUTEX_OS2
+#if !SQLITE_THREADSAFE
+# define SQLITE_MUTEX_OMIT
+#endif
+#if SQLITE_THREADSAFE && !defined(SQLITE_MUTEX_NOOP)
+#  if SQLITE_OS_UNIX
+#    define SQLITE_MUTEX_PTHREADS
+#  elif SQLITE_OS_WIN
+#    define SQLITE_MUTEX_W32
+#  elif SQLITE_OS_OS2
+#    define SQLITE_MUTEX_OS2
+#  else
+#    define SQLITE_MUTEX_NOOP
+#  endif
 #endif
 
-#ifdef SQLITE_MUTEX_NOOP
+#ifdef SQLITE_MUTEX_OMIT
 /*
 ** If this is a no-op implementation, implement everything as macros.
 */
@@ -7449,9 +8817,10 @@ SQLITE_PRIVATE sqlite3_vfs *sqlite3OsDefaultVfs(void);
 #define sqlite3_mutex_leave(X)
 #define sqlite3_mutex_held(X)     1
 #define sqlite3_mutex_notheld(X)  1
-#endif
-
-#endif /* SQLITE_MUTEX_APPDEF */
+#define sqlite3MutexAlloc(X)      ((sqlite3_mutex*)8)
+#define sqlite3MutexInit()        SQLITE_OK
+#define sqlite3MutexEnd()
+#endif /* defined(SQLITE_OMIT_MUTEX) */
 
 /************** End of mutex.h ***********************************************/
 /************** Continuing where we left off in sqliteInt.h ******************/
@@ -7524,6 +8893,48 @@ struct Schema {
 #define DB_UnresetViews    0x0002  /* Some views have defined column names */
 #define DB_Empty           0x0004  /* The file is empty (length 0 bytes) */
 
+/*
+** The number of different kinds of things that can be limited
+** using the sqlite3_limit() interface.
+*/
+#define SQLITE_N_LIMIT (SQLITE_LIMIT_VARIABLE_NUMBER+1)
+
+/*
+** Lookaside malloc is a set of fixed-size buffers that can be used
+** to satisify small transient memory allocation requests for objects
+** associated with a particular database connection.  The use of
+** lookaside malloc provides a significant performance enhancement
+** (approx 10%) by avoiding numerous malloc/free requests while parsing
+** SQL statements.
+**
+** The Lookaside structure holds configuration information about the
+** lookaside malloc subsystem.  Each available memory allocation in
+** the lookaside subsystem is stored on a linked list of LookasideSlot
+** objects.
+*/
+struct Lookaside {
+  u16 sz;                 /* Size of each buffer in bytes */
+  u8 bEnabled;            /* True if use lookaside.  False to ignore it */
+  u8 bMalloced;           /* True if pStart obtained from sqlite3_malloc() */
+  int nOut;               /* Number of buffers currently checked out */
+  int mxOut;              /* Highwater mark for nOut */
+  LookasideSlot *pFree;   /* List of available buffers */
+  void *pStart;           /* First byte of available memory space */
+  void *pEnd;             /* First byte past end of available space */
+};
+struct LookasideSlot {
+  LookasideSlot *pNext;    /* Next buffer in the list of free buffers */
+};
+
+/*
+** A hash table for function definitions.
+**
+** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
+** Collisions are on the FuncDef.pHash chain.
+*/
+struct FuncDefHash {
+  FuncDef *a[23];       /* Hash table for functions */
+};
 
 /*
 ** Each database is an instance of the following structure.
@@ -7562,7 +8973,10 @@ struct sqlite3 {
   u8 autoCommit;                /* The auto-commit flag. */
   u8 temp_store;                /* 1: file 2: memory 0: default */
   u8 mallocFailed;              /* True if we have seen a malloc failure */
+  u8 dfltLockMode;              /* Default locking-mode for attached dbs */
+  u8 dfltJournalMode;           /* Default journal mode for attached dbs */
   signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
+  int nextPagesize;             /* Pagesize after VACUUM if >0 */
   int nTable;                   /* Number of tables in the database */
   CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
   i64 lastRowid;                /* ROWID of most recent insert (see above) */
@@ -7571,6 +8985,7 @@ struct sqlite3 {
   int nChange;                  /* Value returned by sqlite3_changes() */
   int nTotalChange;             /* Value returned by sqlite3_total_changes() */
   sqlite3_mutex *mutex;         /* Connection mutex */
+  int aLimit[SQLITE_N_LIMIT];   /* Limits */
   struct sqlite3InitInfo {      /* Information used during initialization */
     int iDb;                    /* When back is being initialized */
     int newTnum;                /* Rootpage of table being initialized */
@@ -7597,9 +9012,10 @@ struct sqlite3 {
   char *zErrMsg;                /* Most recent error message (UTF-8 encoded) */
   char *zErrMsg16;              /* Most recent error message (UTF-16 encoded) */
   union {
-    int isInterrupted;          /* True if sqlite3_interrupt has been called */
+    volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
     double notUsed1;            /* Spacer */
   } u1;
+  Lookaside lookaside;          /* Lookaside malloc configuration */
 #ifndef SQLITE_OMIT_AUTHORIZATION
   int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
                                 /* Access authorization function */
@@ -7616,7 +9032,7 @@ struct sqlite3 {
   sqlite3_vtab **aVTrans;       /* Virtual tables with open transactions */
   int nVTrans;                  /* Allocated size of aVTrans */
 #endif
-  Hash aFunc;                   /* All functions that can be in SQL exprs */
+  FuncDefHash aFunc;            /* Hash table of connection functions */
   Hash aCollSeq;                /* All collating sequences */
   BusyHandler busyHandler;      /* Busy callback */
   int busyTimeout;              /* Busy handler timeout, in msec */
@@ -7624,7 +9040,6 @@ struct sqlite3 {
 #ifdef SQLITE_SSE
   sqlite3_stmt *pFetch;         /* Used by SSE to fetch stored statements */
 #endif
-  u8 dfltLockMode;              /* Default locking-mode for attached dbs */
 };
 
 /*
@@ -7684,17 +9099,60 @@ struct sqlite3 {
 struct FuncDef {
   i16 nArg;            /* Number of arguments.  -1 means unlimited */
   u8 iPrefEnc;         /* Preferred text encoding (SQLITE_UTF8, 16LE, 16BE) */
-  u8 needCollSeq;      /* True if sqlite3GetFuncCollSeq() might be called */
   u8 flags;            /* Some combination of SQLITE_FUNC_* */
   void *pUserData;     /* User data parameter */
   FuncDef *pNext;      /* Next function with same name */
   void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
   void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
   void (*xFinalize)(sqlite3_context*);                /* Aggregate finializer */
-  char zName[1];       /* SQL name of the function.  MUST BE LAST */
+  char *zName;         /* SQL name of the function. */
+  FuncDef *pHash;      /* Next with a different name but the same hash */
 };
 
 /*
+** Possible values for FuncDef.flags
+*/
+#define SQLITE_FUNC_LIKE     0x01 /* Candidate for the LIKE optimization */
+#define SQLITE_FUNC_CASE     0x02 /* Case-sensitive LIKE-type function */
+#define SQLITE_FUNC_EPHEM    0x04 /* Ephermeral.  Delete with VDBE */
+#define SQLITE_FUNC_NEEDCOLL 0x08 /* sqlite3GetFuncCollSeq() might be called */
+
+/*
+** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
+** used to create the initializers for the FuncDef structures.
+**
+**   FUNCTION(zName, nArg, iArg, bNC, xFunc)
+**     Used to create a scalar function definition of a function zName 
+**     implemented by C function xFunc that accepts nArg arguments. The
+**     value passed as iArg is cast to a (void*) and made available
+**     as the user-data (sqlite3_user_data()) for the function. If 
+**     argument bNC is true, then the FuncDef.needCollate flag is set.
+**
+**   AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
+**     Used to create an aggregate function definition implemented by
+**     the C functions xStep and xFinal. The first four parameters
+**     are interpreted in the same way as the first 4 parameters to
+**     FUNCTION().
+**
+**   LIKEFUNC(zName, nArg, pArg, flags)
+**     Used to create a scalar function definition of a function zName 
+**     that accepts nArg arguments and is implemented by a call to C 
+**     function likeFunc. Argument pArg is cast to a (void *) and made
+**     available as the function user-data (sqlite3_user_data()). The
+**     FuncDef.flags variable is set to the value passed as the flags
+**     parameter.
+*/
+#define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
+  {nArg, SQLITE_UTF8, bNC*8, SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName}
+#define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
+  {nArg, SQLITE_UTF8, bNC*8, pArg, 0, xFunc, 0, 0, #zName}
+#define LIKEFUNC(zName, nArg, arg, flags) \
+  {nArg, SQLITE_UTF8, flags, (void *)arg, 0, likeFunc, 0, 0, #zName}
+#define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
+  {nArg, SQLITE_UTF8, nc*8, SQLITE_INT_TO_PTR(arg), 0, 0, xStep,xFinal, #zName}
+
+
+/*
 ** Each SQLite module (virtual table definition) is defined by an
 ** instance of the following structure, stored in the sqlite3.aModule
 ** hash table.
@@ -7707,13 +9165,6 @@ struct Module {
 };
 
 /*
-** Possible values for FuncDef.flags
-*/
-#define SQLITE_FUNC_LIKE   0x01  /* Candidate for the LIKE optimization */
-#define SQLITE_FUNC_CASE   0x02  /* Case-sensitive LIKE-type function */
-#define SQLITE_FUNC_EPHEM  0x04  /* Ephermeral.  Delete with VDBE */
-
-/*
 ** information about each column of an SQL table is held in an instance
 ** of this structure.
 */
@@ -7761,7 +9212,7 @@ struct CollSeq {
 };
 
 /*
-** Allowed values of CollSeq flags:
+** Allowed values of CollSeq.type:
 */
 #define SQLITE_COLL_BINARY  1  /* The default memcmp() collating sequence */
 #define SQLITE_COLL_NOCASE  2  /* The built-in NOCASE collating sequence */
@@ -7779,7 +9230,7 @@ struct CollSeq {
 **
 ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
 ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
-** the speed a little by number the values consecutively.  
+** the speed a little by numbering the values consecutively.  
 **
 ** But rather than start with 0 or 1, we begin with 'a'.  That way,
 ** when multiple affinity types are concatenated into a string and
@@ -7807,8 +9258,7 @@ struct CollSeq {
 ** changing the affinity.
 */
 #define SQLITE_JUMPIFNULL   0x08  /* jumps if either operand is NULL */
-#define SQLITE_NULLEQUAL    0x10  /* compare NULLs equal */
-#define SQLITE_STOREP2      0x80  /* Store result in reg[P2] rather than jump */
+#define SQLITE_STOREP2      0x10  /* Store result in reg[P2] rather than jump */
 
 /*
 ** Each SQL table is represented in memory by an instance of the
@@ -7826,14 +9276,14 @@ struct CollSeq {
 ** that the datatype of the PRIMARY KEY must be INTEGER for this field to
 ** be set.  An INTEGER PRIMARY KEY is used as the rowid for each row of
 ** the table.  If a table has no INTEGER PRIMARY KEY, then a random rowid
-** is generated for each row of the table.  Table.hasPrimKey is true if
+** is generated for each row of the table.  TF_HasPrimaryKey is set if
 ** the table has any PRIMARY KEY, INTEGER or otherwise.
 **
 ** Table.tnum is the page number for the root BTree page of the table in the
 ** database file.  If Table.iDb is the index of the database table backend
 ** in sqlite.aDb[].  0 is for the main database and 1 is for the file that
-** holds temporary tables and indices.  If Table.isEphem
-** is true, then the table is stored in a file that is automatically deleted
+** holds temporary tables and indices.  If TF_Ephemeral is set
+** then the table is stored in a file that is automatically deleted
 ** when the VDBE cursor to the table is closed.  In this case Table.tnum 
 ** refers VDBE cursor number that holds the table open, not to the root
 ** page number.  Transient tables are used to hold the results of a
@@ -7841,46 +9291,55 @@ struct CollSeq {
 ** of a SELECT statement.
 */
 struct Table {
-  char *zName;     /* Name of the table */
-  int nCol;        /* Number of columns in this table */
-  Column *aCol;    /* Information about each column */
-  int iPKey;       /* If not less then 0, use aCol[iPKey] as the primary key */
-  Index *pIndex;   /* List of SQL indexes on this table. */
-  int tnum;        /* Root BTree node for this table (see note above) */
-  Select *pSelect; /* NULL for tables.  Points to definition if a view. */
-  int nRef;          /* Number of pointers to this Table */
-  Trigger *pTrigger; /* List of SQL triggers on this table */
-  FKey *pFKey;       /* Linked list of all foreign keys in this table */
-  char *zColAff;     /* String defining the affinity of each column */
+  sqlite3 *db;         /* Associated database connection.  Might be NULL. */
+  char *zName;         /* Name of the table or view */
+  int iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
+  int nCol;            /* Number of columns in this table */
+  Column *aCol;        /* Information about each column */
+  Index *pIndex;       /* List of SQL indexes on this table. */
+  int tnum;            /* Root BTree node for this table (see note above) */
+  Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
+  u16 nRef;            /* Number of pointers to this Table */
+  u8 tabFlags;         /* Mask of TF_* values */
+  u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
+  Trigger *pTrigger;   /* List of SQL triggers on this table */
+  FKey *pFKey;         /* Linked list of all foreign keys in this table */
+  char *zColAff;       /* String defining the affinity of each column */
 #ifndef SQLITE_OMIT_CHECK
-  Expr *pCheck;      /* The AND of all CHECK constraints */
+  Expr *pCheck;        /* The AND of all CHECK constraints */
 #endif
 #ifndef SQLITE_OMIT_ALTERTABLE
-  int addColOffset;  /* Offset in CREATE TABLE statement to add a new column */
+  int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
 #endif
-  u8 readOnly;     /* True if this table should not be written by the user */
-  u8 isEphem;      /* True if created using OP_OpenEphermeral */
-  u8 hasPrimKey;   /* True if there exists a primary key */
-  u8 keyConf;      /* What to do in case of uniqueness conflict on iPKey */
-  u8 autoInc;      /* True if the integer primary key is autoincrement */
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-  u8 isVirtual;             /* True if this is a virtual table */
-  u8 isCommit;              /* True once the CREATE TABLE has been committed */
-  Module *pMod;             /* Pointer to the implementation of the module */
-  sqlite3_vtab *pVtab;      /* Pointer to the module instance */
-  int nModuleArg;           /* Number of arguments to the module */
-  char **azModuleArg;       /* Text of all module args. [0] is module name */
-#endif
-  Schema *pSchema;          /* Schema that contains this table */
+  Module *pMod;        /* Pointer to the implementation of the module */
+  sqlite3_vtab *pVtab; /* Pointer to the module instance */
+  int nModuleArg;      /* Number of arguments to the module */
+  char **azModuleArg;  /* Text of all module args. [0] is module name */
+#endif
+  Schema *pSchema;     /* Schema that contains this table */
+  Table *pNextZombie;  /* Next on the Parse.pZombieTab list */
 };
 
 /*
+** Allowed values for Tabe.tabFlags.
+*/
+#define TF_Readonly        0x01    /* Read-only system table */
+#define TF_Ephemeral       0x02    /* An emphermal table */
+#define TF_HasPrimaryKey   0x04    /* Table has a primary key */
+#define TF_Autoincrement   0x08    /* Integer primary key is autoincrement */
+#define TF_Virtual         0x10    /* Is a virtual table */
+#define TF_NeedMetadata    0x20    /* aCol[].zType and aCol[].pColl missing */
+
+
+
+/*
 ** Test to see whether or not a table is a virtual table.  This is
 ** done as a macro so that it will be optimized out when virtual
 ** table support is omitted from the build.
 */
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-#  define IsVirtual(X)      ((X)->isVirtual)
+#  define IsVirtual(X)      (((X)->tabFlags & TF_Virtual)!=0)
 #  define IsHiddenColumn(X) ((X)->isHidden)
 #else
 #  define IsVirtual(X)      0
@@ -7972,22 +9431,46 @@ struct FKey {
 ** An instance of the following structure is passed as the first
 ** argument to sqlite3VdbeKeyCompare and is used to control the 
 ** comparison of the two index keys.
-**
-** If the KeyInfo.incrKey value is true and the comparison would
-** otherwise be equal, then return a result as if the second key
-** were larger.
 */
 struct KeyInfo {
   sqlite3 *db;        /* The database connection */
   u8 enc;             /* Text encoding - one of the TEXT_Utf* values */
-  u8 incrKey;         /* Increase 2nd key by epsilon before comparison */
-  u8 prefixIsEqual;   /* Treat a prefix as equal */
-  int nField;         /* Number of entries in aColl[] */
+  u16 nField;         /* Number of entries in aColl[] */
   u8 *aSortOrder;     /* If defined an aSortOrder[i] is true, sort DESC */
   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
 };
 
 /*
+** An instance of the following structure holds information about a
+** single index record that has already been parsed out into individual
+** values.
+**
+** A record is an object that contains one or more fields of data.
+** Records are used to store the content of a table row and to store
+** the key of an index.  A blob encoding of a record is created by
+** the OP_MakeRecord opcode of the VDBE and is disassemblied by the
+** OP_Column opcode.
+**
+** This structure holds a record that has already been disassembled
+** into its constitutent fields.
+*/
+struct UnpackedRecord {
+  KeyInfo *pKeyInfo;  /* Collation and sort-order information */
+  u16 nField;         /* Number of entries in apMem[] */
+  u16 flags;          /* Boolean settings.  UNPACKED_... below */
+  Mem *aMem;          /* Values */
+};
+
+/*
+** Allowed values of UnpackedRecord.flags
+*/
+#define UNPACKED_NEED_FREE     0x0001  /* Memory is from sqlite3Malloc() */
+#define UNPACKED_NEED_DESTROY  0x0002  /* apMem[]s should all be destroyed */
+#define UNPACKED_IGNORE_ROWID  0x0004  /* Ignore trailing rowid on key1 */
+#define UNPACKED_INCRKEY       0x0008  /* Make this key an epsilon larger */
+#define UNPACKED_PREFIX_MATCH  0x0010  /* A prefix match is considered OK */
+
+/*
 ** Each SQL index is represented in memory by an
 ** instance of the following structure.
 **
@@ -8150,9 +9633,8 @@ struct Expr {
   int iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
   Select *pSelect;       /* When the expression is a sub-select.  Also the
                          ** right side of " IN (
+** Wildcards consisting of a single "?" are assigned the next sequential
+** variable number.
 **
-** If the mustBeUnique parameter is false, the structure will be used 
-** for fast set membership tests. In this case an epheremal table must 
-** be used unless  is an INTEGER PRIMARY KEY or an index can 
-** be found with  as its left-most column.
+** Wildcards of the form "?nnn" are assigned the number "nnn".  We make
+** sure "nnn" is not too be to avoid a denial of service attack when
+** the SQL statement comes from an external source.
 **
-** If mustBeUnique is true, then the structure will be used to iterate
-** through the set members, skipping any duplicates. In this case an
-** epheremal table must be used unless the selected  is guaranteed
-** to be unique - either because it is an INTEGER PRIMARY KEY or it
-** is unique by virtue of a constraint or implicit index.
+** Wildcards of the form ":aaa" or "$aaa" are assigned the same number
+** as the previous instance of the same wildcard.  Or if this is the first
+** instance of the wildcard, the next sequenial variable number is
+** assigned.
 */
-#ifndef SQLITE_OMIT_SUBQUERY
-SQLITE_PRIVATE int sqlite3FindInIndex(Parse *pParse, Expr *pX, int mustBeUnique){
-  Select *p;
-  int eType = 0;
-  int iTab = pParse->nTab++;
-
-  /* The follwing if(...) expression is true if the SELECT is of the 
-  ** simple form:
-  **
-  **     SELECT  FROM 
      
-  **
-  ** If this is the case, it may be possible to use an existing table
-  ** or index instead of generating an epheremal table.
-  */
-  if( sqlite3_enable_in_opt
-   && (p=pX->pSelect)!=0 && !p->pPrior
-   && !p->isDistinct && !p->isAgg && !p->pGroupBy
-   && p->pSrc && p->pSrc->nSrc==1 && !p->pSrc->a[0].pSelect
-   && p->pSrc->a[0].pTab && !p->pSrc->a[0].pTab->pSelect
-   && p->pEList->nExpr==1 && p->pEList->a[0].pExpr->op==TK_COLUMN
-   && !p->pLimit && !p->pOffset && !p->pWhere
-  ){
-    sqlite3 *db = pParse->db;
-    Index *pIdx;
-    Expr *pExpr = p->pEList->a[0].pExpr;
-    int iCol = pExpr->iColumn;
-    Vdbe *v = sqlite3GetVdbe(pParse);
+SQLITE_PRIVATE void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){
+  Token *pToken;
+  sqlite3 *db = pParse->db;
 
-    /* This function is only called from two places. In both cases the vdbe
-    ** has already been allocated. So assume sqlite3GetVdbe() is always
-    ** successful here.
+  if( pExpr==0 ) return;
+  pToken = &pExpr->token;
+  assert( pToken->n>=1 );
+  assert( pToken->z!=0 );
+  assert( pToken->z[0]!=0 );
+  if( pToken->n==1 ){
+    /* Wildcard of the form "?".  Assign the next variable number */
+    pExpr->iTable = ++pParse->nVar;
+  }else if( pToken->z[0]=='?' ){
+    /* Wildcard of the form "?nnn".  Convert "nnn" to an integer and
+    ** use it as the variable number */
+    int i;
+    pExpr->iTable = i = atoi((char*)&pToken->z[1]);
+    testcase( i==0 );
+    testcase( i==1 );
+    testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]-1 );
+    testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] );
+    if( i<1 || i>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
+      sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d",
+          db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]);
+    }
+    if( i>pParse->nVar ){
+      pParse->nVar = i;
+    }
+  }else{
+    /* Wildcards of the form ":aaa" or "$aaa".  Reuse the same variable
+    ** number as the prior appearance of the same name, or if the name
+    ** has never appeared before, reuse the same variable number
     */
-    assert(v);
-    if( iCol<0 ){
-      int iMem = ++pParse->nMem;
-      int iAddr;
-      Table *pTab = p->pSrc->a[0].pTab;
-      int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
-      sqlite3VdbeUsesBtree(v, iDb);
-
-      iAddr = sqlite3VdbeAddOp1(v, OP_If, iMem);
-      sqlite3VdbeAddOp2(v, OP_Integer, 1, iMem);
-
-      sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
-      eType = IN_INDEX_ROWID;
-
-      sqlite3VdbeJumpHere(v, iAddr);
-    }else{
-      /* The collation sequence used by the comparison. If an index is to 
-      ** be used in place of a temp-table, it must be ordered according
-      ** to this collation sequence.
-      */
-      CollSeq *pReq = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pExpr);
-
-      /* Check that the affinity that will be used to perform the 
-      ** comparison is the same as the affinity of the column. If
-      ** it is not, it is not possible to use any index.
-      */
-      Table *pTab = p->pSrc->a[0].pTab;
-      char aff = comparisonAffinity(pX);
-      int affinity_ok = (pTab->aCol[iCol].affinity==aff||aff==SQLITE_AFF_NONE);
-
-      for(pIdx=pTab->pIndex; pIdx && eType==0 && affinity_ok; pIdx=pIdx->pNext){
-        if( (pIdx->aiColumn[0]==iCol)
-         && (pReq==sqlite3FindCollSeq(db, ENC(db), pIdx->azColl[0], -1, 0))
-         && (!mustBeUnique || (pIdx->nColumn==1 && pIdx->onError!=OE_None))
-        ){
-          int iDb;
-          int iMem = ++pParse->nMem;
-          int iAddr;
-          char *pKey;
-  
-          pKey = (char *)sqlite3IndexKeyinfo(pParse, pIdx);
-          iDb = sqlite3SchemaToIndex(db, pIdx->pSchema);
-          sqlite3VdbeUsesBtree(v, iDb);
-
-          iAddr = sqlite3VdbeAddOp1(v, OP_If, iMem);
-          sqlite3VdbeAddOp2(v, OP_Integer, 1, iMem);
-  
-          sqlite3VdbeAddOp4(v, OP_OpenRead, iTab, pIdx->tnum, iDb,
-                               pKey,P4_KEYINFO_HANDOFF);
-          VdbeComment((v, "%s", pIdx->zName));
-          eType = IN_INDEX_INDEX;
-          sqlite3VdbeAddOp2(v, OP_SetNumColumns, iTab, pIdx->nColumn);
-
-          sqlite3VdbeJumpHere(v, iAddr);
-        }
+    int i, n;
+    n = pToken->n;
+    for(i=0; inVarExpr; i++){
+      Expr *pE;
+      if( (pE = pParse->apVarExpr[i])!=0
+          && pE->token.n==n
+          && memcmp(pE->token.z, pToken->z, n)==0 ){
+        pExpr->iTable = pE->iTable;
+        break;
       }
     }
+    if( i>=pParse->nVarExpr ){
+      pExpr->iTable = ++pParse->nVar;
+      if( pParse->nVarExpr>=pParse->nVarExprAlloc-1 ){
+        pParse->nVarExprAlloc += pParse->nVarExprAlloc + 10;
+        pParse->apVarExpr =
+            sqlite3DbReallocOrFree(
+              db,
+              pParse->apVarExpr,
+              pParse->nVarExprAlloc*sizeof(pParse->apVarExpr[0])
+            );
+      }
+      if( !db->mallocFailed ){
+        assert( pParse->apVarExpr!=0 );
+        pParse->apVarExpr[pParse->nVarExpr++] = pExpr;
+      }
+    }
+  } 
+  if( !pParse->nErr && pParse->nVar>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
+    sqlite3ErrorMsg(pParse, "too many SQL variables");
   }
-
-  if( eType==0 ){
-    sqlite3CodeSubselect(pParse, pX);
-    eType = IN_INDEX_EPH;
-  }else{
-    pX->iTable = iTab;
-  }
-  return eType;
 }
-#endif
 
 /*
-** Generate code for scalar subqueries used as an expression
-** and IN operators.  Examples:
-**
-**     (SELECT a FROM b)          -- subquery
-**     EXISTS (SELECT a FROM b)   -- EXISTS subquery
-**     x IN (4,5,11)              -- IN operator with list on right-hand side
-**     x IN (SELECT a FROM b)     -- IN operator with subquery on the right
-**
-** The pExpr parameter describes the expression that contains the IN
-** operator or subquery.
+** Clear an expression structure without deleting the structure itself.
+** Substructure is deleted.
 */
-#ifndef SQLITE_OMIT_SUBQUERY
-SQLITE_PRIVATE void sqlite3CodeSubselect(Parse *pParse, Expr *pExpr){
-  int testAddr = 0;                       /* One-time test address */
-  Vdbe *v = sqlite3GetVdbe(pParse);
-  if( v==0 ) return;
+SQLITE_PRIVATE void sqlite3ExprClear(sqlite3 *db, Expr *p){
+  if( p->span.dyn ) sqlite3DbFree(db, (char*)p->span.z);
+  if( p->token.dyn ) sqlite3DbFree(db, (char*)p->token.z);
+  sqlite3ExprDelete(db, p->pLeft);
+  sqlite3ExprDelete(db, p->pRight);
+  sqlite3ExprListDelete(db, p->pList);
+  sqlite3SelectDelete(db, p->pSelect);
+}
 
+/*
+** Recursively delete an expression tree.
+*/
+SQLITE_PRIVATE void sqlite3ExprDelete(sqlite3 *db, Expr *p){
+  if( p==0 ) return;
+  sqlite3ExprClear(db, p);
+  sqlite3DbFree(db, p);
+}
 
-  /* This code must be run in its entirety every time it is encountered
-  ** if any of the following is true:
-  **
-  **    *  The right-hand side is a correlated subquery
-  **    *  The right-hand side is an expression list containing variables
-  **    *  We are inside a trigger
-  **
-  ** If all of the above are false, then we can run this code just once
-  ** save the results, and reuse the same result on subsequent invocations.
-  */
-  if( !ExprHasAnyProperty(pExpr, EP_VarSelect) && !pParse->trigStack ){
-    int mem = ++pParse->nMem;
-    sqlite3VdbeAddOp1(v, OP_If, mem);
-    testAddr = sqlite3VdbeAddOp2(v, OP_Integer, 1, mem);
-    assert( testAddr>0 || pParse->db->mallocFailed );
+/*
+** The Expr.token field might be a string literal that is quoted.
+** If so, remove the quotation marks.
+*/
+SQLITE_PRIVATE void sqlite3DequoteExpr(sqlite3 *db, Expr *p){
+  if( ExprHasAnyProperty(p, EP_Dequoted) ){
+    return;
   }
+  ExprSetProperty(p, EP_Dequoted);
+  if( p->token.dyn==0 ){
+    sqlite3TokenCopy(db, &p->token, &p->token);
+  }
+  sqlite3Dequote((char*)p->token.z);
+}
 
-  switch( pExpr->op ){
-    case TK_IN: {
-      char affinity;
-      KeyInfo keyInfo;
-      int addr;        /* Address of OP_OpenEphemeral instruction */
-
-      affinity = sqlite3ExprAffinity(pExpr->pLeft);
-
-      /* Whether this is an 'x IN(SELECT...)' or an 'x IN()'
-      ** expression it is handled the same way. A virtual table is 
-      ** filled with single-field index keys representing the results
-      ** from the SELECT or the .
-      **
-      ** If the 'x' expression is a column value, or the SELECT...
-      ** statement returns a column value, then the affinity of that
-      ** column is used to build the index keys. If both 'x' and the
-      ** SELECT... statement are columns, then numeric affinity is used
-      ** if either column has NUMERIC or INTEGER affinity. If neither
-      ** 'x' nor the SELECT... statement are columns, then numeric affinity
-      ** is used.
-      */
-      pExpr->iTable = pParse->nTab++;
-      addr = sqlite3VdbeAddOp1(v, OP_OpenEphemeral, pExpr->iTable);
-      memset(&keyInfo, 0, sizeof(keyInfo));
-      keyInfo.nField = 1;
-      sqlite3VdbeAddOp2(v, OP_SetNumColumns, pExpr->iTable, 1);
-
-      if( pExpr->pSelect ){
-        /* Case 1:     expr IN (SELECT ...)
-        **
-        ** Generate code to write the results of the select into the temporary
-        ** table allocated and opened above.
-        */
-        SelectDest dest;
-        ExprList *pEList;
-
-        sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
-        dest.affinity = (int)affinity;
-        assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
-        if( sqlite3Select(pParse, pExpr->pSelect, &dest, 0, 0, 0, 0) ){
-          return;
-        }
-        pEList = pExpr->pSelect->pEList;
-        if( pEList && pEList->nExpr>0 ){ 
-          keyInfo.aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft,
-              pEList->a[0].pExpr);
-        }
-      }else if( pExpr->pList ){
-        /* Case 2:     expr IN (exprlist)
-        **
-        ** For each expression, build an index key from the evaluation and
-        ** store it in the temporary table. If  is a column, then use
-        ** that columns affinity when building index keys. If  is not
-        ** a column, use numeric affinity.
-        */
-        int i;
-        ExprList *pList = pExpr->pList;
-        struct ExprList_item *pItem;
-        int r1, r2;
-
-        if( !affinity ){
-          affinity = SQLITE_AFF_NONE;
-        }
-        keyInfo.aColl[0] = pExpr->pLeft->pColl;
-
-        /* Loop through each expression in . */
-        r1 = sqlite3GetTempReg(pParse);
-        r2 = sqlite3GetTempReg(pParse);
-        for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){
-          Expr *pE2 = pItem->pExpr;
-
-          /* If the expression is not constant then we will need to
-          ** disable the test that was generated above that makes sure
-          ** this code only executes once.  Because for a non-constant
-          ** expression we need to rerun this code each time.
-          */
-          if( testAddr && !sqlite3ExprIsConstant(pE2) ){
-            sqlite3VdbeChangeToNoop(v, testAddr-1, 2);
-            testAddr = 0;
-          }
+/*
+** The following group of routines make deep copies of expressions,
+** expression lists, ID lists, and select statements.  The copies can
+** be deleted (by being passed to their respective ...Delete() routines)
+** without effecting the originals.
+**
+** The expression list, ID, and source lists return by sqlite3ExprListDup(),
+** sqlite3IdListDup(), and sqlite3SrcListDup() can not be further expanded 
+** by subsequent calls to sqlite*ListAppend() routines.
+**
+** Any tables that the SrcList might point to are not duplicated.
+*/
+SQLITE_PRIVATE Expr *sqlite3ExprDup(sqlite3 *db, Expr *p){
+  Expr *pNew;
+  if( p==0 ) return 0;
+  pNew = sqlite3DbMallocRaw(db, sizeof(*p) );
+  if( pNew==0 ) return 0;
+  memcpy(pNew, p, sizeof(*pNew));
+  if( p->token.z!=0 ){
+    pNew->token.z = (u8*)sqlite3DbStrNDup(db, (char*)p->token.z, p->token.n);
+    pNew->token.dyn = 1;
+  }else{
+    assert( pNew->token.z==0 );
+  }
+  pNew->span.z = 0;
+  pNew->pLeft = sqlite3ExprDup(db, p->pLeft);
+  pNew->pRight = sqlite3ExprDup(db, p->pRight);
+  pNew->pList = sqlite3ExprListDup(db, p->pList);
+  pNew->pSelect = sqlite3SelectDup(db, p->pSelect);
+  return pNew;
+}
+SQLITE_PRIVATE void sqlite3TokenCopy(sqlite3 *db, Token *pTo, Token *pFrom){
+  if( pTo->dyn ) sqlite3DbFree(db, (char*)pTo->z);
+  if( pFrom->z ){
+    pTo->n = pFrom->n;
+    pTo->z = (u8*)sqlite3DbStrNDup(db, (char*)pFrom->z, pFrom->n);
+    pTo->dyn = 1;
+  }else{
+    pTo->z = 0;
+  }
+}
+SQLITE_PRIVATE ExprList *sqlite3ExprListDup(sqlite3 *db, ExprList *p){
+  ExprList *pNew;
+  struct ExprList_item *pItem, *pOldItem;
+  int i;
+  if( p==0 ) return 0;
+  pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
+  if( pNew==0 ) return 0;
+  pNew->iECursor = 0;
+  pNew->nExpr = pNew->nAlloc = p->nExpr;
+  pNew->a = pItem = sqlite3DbMallocRaw(db,  p->nExpr*sizeof(p->a[0]) );
+  if( pItem==0 ){
+    sqlite3DbFree(db, pNew);
+    return 0;
+  } 
+  pOldItem = p->a;
+  for(i=0; inExpr; i++, pItem++, pOldItem++){
+    Expr *pNewExpr, *pOldExpr;
+    pItem->pExpr = pNewExpr = sqlite3ExprDup(db, pOldExpr = pOldItem->pExpr);
+    if( pOldExpr->span.z!=0 && pNewExpr ){
+      /* Always make a copy of the span for top-level expressions in the
+      ** expression list.  The logic in SELECT processing that determines
+      ** the names of columns in the result set needs this information */
+      sqlite3TokenCopy(db, &pNewExpr->span, &pOldExpr->span);
+    }
+    assert( pNewExpr==0 || pNewExpr->span.z!=0 
+            || pOldExpr->span.z==0
+            || db->mallocFailed );
+    pItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
+    pItem->sortOrder = pOldItem->sortOrder;
+    pItem->done = 0;
+    pItem->iCol = pOldItem->iCol;
+    pItem->iAlias = pOldItem->iAlias;
+  }
+  return pNew;
+}
 
-          /* Evaluate the expression and insert it into the temp table */
-          sqlite3ExprCode(pParse, pE2, r1);
-          sqlite3VdbeAddOp4(v, OP_MakeRecord, r1, 1, r2, &affinity, 1);
-          sqlite3VdbeAddOp2(v, OP_IdxInsert, pExpr->iTable, r2);
-        }
-        sqlite3ReleaseTempReg(pParse, r1);
-        sqlite3ReleaseTempReg(pParse, r2);
-      }
-      sqlite3VdbeChangeP4(v, addr, (void *)&keyInfo, P4_KEYINFO);
-      break;
+/*
+** If cursors, triggers, views and subqueries are all omitted from
+** the build, then none of the following routines, except for 
+** sqlite3SelectDup(), can be called. sqlite3SelectDup() is sometimes
+** called with a NULL argument.
+*/
+#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER) \
+ || !defined(SQLITE_OMIT_SUBQUERY)
+SQLITE_PRIVATE SrcList *sqlite3SrcListDup(sqlite3 *db, SrcList *p){
+  SrcList *pNew;
+  int i;
+  int nByte;
+  if( p==0 ) return 0;
+  nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
+  pNew = sqlite3DbMallocRaw(db, nByte );
+  if( pNew==0 ) return 0;
+  pNew->nSrc = pNew->nAlloc = p->nSrc;
+  for(i=0; inSrc; i++){
+    struct SrcList_item *pNewItem = &pNew->a[i];
+    struct SrcList_item *pOldItem = &p->a[i];
+    Table *pTab;
+    pNewItem->zDatabase = sqlite3DbStrDup(db, pOldItem->zDatabase);
+    pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
+    pNewItem->zAlias = sqlite3DbStrDup(db, pOldItem->zAlias);
+    pNewItem->jointype = pOldItem->jointype;
+    pNewItem->iCursor = pOldItem->iCursor;
+    pNewItem->isPopulated = pOldItem->isPopulated;
+    pNewItem->zIndex = sqlite3DbStrDup(db, pOldItem->zIndex);
+    pNewItem->notIndexed = pOldItem->notIndexed;
+    pNewItem->pIndex = pOldItem->pIndex;
+    pTab = pNewItem->pTab = pOldItem->pTab;
+    if( pTab ){
+      pTab->nRef++;
     }
+    pNewItem->pSelect = sqlite3SelectDup(db, pOldItem->pSelect);
+    pNewItem->pOn = sqlite3ExprDup(db, pOldItem->pOn);
+    pNewItem->pUsing = sqlite3IdListDup(db, pOldItem->pUsing);
+    pNewItem->colUsed = pOldItem->colUsed;
+  }
+  return pNew;
+}
+SQLITE_PRIVATE IdList *sqlite3IdListDup(sqlite3 *db, IdList *p){
+  IdList *pNew;
+  int i;
+  if( p==0 ) return 0;
+  pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
+  if( pNew==0 ) return 0;
+  pNew->nId = pNew->nAlloc = p->nId;
+  pNew->a = sqlite3DbMallocRaw(db, p->nId*sizeof(p->a[0]) );
+  if( pNew->a==0 ){
+    sqlite3DbFree(db, pNew);
+    return 0;
+  }
+  for(i=0; inId; i++){
+    struct IdList_item *pNewItem = &pNew->a[i];
+    struct IdList_item *pOldItem = &p->a[i];
+    pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
+    pNewItem->idx = pOldItem->idx;
+  }
+  return pNew;
+}
+SQLITE_PRIVATE Select *sqlite3SelectDup(sqlite3 *db, Select *p){
+  Select *pNew;
+  if( p==0 ) return 0;
+  pNew = sqlite3DbMallocRaw(db, sizeof(*p) );
+  if( pNew==0 ) return 0;
+  pNew->pEList = sqlite3ExprListDup(db, p->pEList);
+  pNew->pSrc = sqlite3SrcListDup(db, p->pSrc);
+  pNew->pWhere = sqlite3ExprDup(db, p->pWhere);
+  pNew->pGroupBy = sqlite3ExprListDup(db, p->pGroupBy);
+  pNew->pHaving = sqlite3ExprDup(db, p->pHaving);
+  pNew->pOrderBy = sqlite3ExprListDup(db, p->pOrderBy);
+  pNew->op = p->op;
+  pNew->pPrior = sqlite3SelectDup(db, p->pPrior);
+  pNew->pLimit = sqlite3ExprDup(db, p->pLimit);
+  pNew->pOffset = sqlite3ExprDup(db, p->pOffset);
+  pNew->iLimit = 0;
+  pNew->iOffset = 0;
+  pNew->selFlags = p->selFlags & ~SF_UsesEphemeral;
+  pNew->pRightmost = 0;
+  pNew->addrOpenEphm[0] = -1;
+  pNew->addrOpenEphm[1] = -1;
+  pNew->addrOpenEphm[2] = -1;
+  return pNew;
+}
+#else
+SQLITE_PRIVATE Select *sqlite3SelectDup(sqlite3 *db, Select *p){
+  assert( p==0 );
+  return 0;
+}
+#endif
 
-    case TK_EXISTS:
-    case TK_SELECT: {
-      /* This has to be a scalar SELECT.  Generate code to put the
-      ** value of this select in a memory cell and record the number
-      ** of the memory cell in iColumn.
-      */
-      static const Token one = { (u8*)"1", 0, 1 };
-      Select *pSel;
-      SelectDest dest;
 
-      pSel = pExpr->pSelect;
-      sqlite3SelectDestInit(&dest, 0, ++pParse->nMem);
-      if( pExpr->op==TK_SELECT ){
-        dest.eDest = SRT_Mem;
-        sqlite3VdbeAddOp2(v, OP_Null, 0, dest.iParm);
-        VdbeComment((v, "Init subquery result"));
-      }else{
-        dest.eDest = SRT_Exists;
-        sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iParm);
-        VdbeComment((v, "Init EXISTS result"));
-      }
-      sqlite3ExprDelete(pSel->pLimit);
-      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, &one);
-      if( sqlite3Select(pParse, pSel, &dest, 0, 0, 0, 0) ){
-        return;
-      }
-      pExpr->iColumn = dest.iParm;
-      break;
+/*
+** Add a new element to the end of an expression list.  If pList is
+** initially NULL, then create a new expression list.
+*/
+SQLITE_PRIVATE ExprList *sqlite3ExprListAppend(
+  Parse *pParse,          /* Parsing context */
+  ExprList *pList,        /* List to which to append. Might be NULL */
+  Expr *pExpr,            /* Expression to be appended */
+  Token *pName            /* AS keyword for the expression */
+){
+  sqlite3 *db = pParse->db;
+  if( pList==0 ){
+    pList = sqlite3DbMallocZero(db, sizeof(ExprList) );
+    if( pList==0 ){
+      goto no_mem;
     }
+    assert( pList->nAlloc==0 );
   }
-
-  if( testAddr ){
-    sqlite3VdbeJumpHere(v, testAddr-1);
+  if( pList->nAlloc<=pList->nExpr ){
+    struct ExprList_item *a;
+    int n = pList->nAlloc*2 + 4;
+    a = sqlite3DbRealloc(db, pList->a, n*sizeof(pList->a[0]));
+    if( a==0 ){
+      goto no_mem;
+    }
+    pList->a = a;
+    pList->nAlloc = n;
+  }
+  assert( pList->a!=0 );
+  if( pExpr || pName ){
+    struct ExprList_item *pItem = &pList->a[pList->nExpr++];
+    memset(pItem, 0, sizeof(*pItem));
+    pItem->zName = sqlite3NameFromToken(db, pName);
+    pItem->pExpr = pExpr;
+    pItem->iAlias = 0;
   }
+  return pList;
 
-  return;
+no_mem:     
+  /* Avoid leaking memory if malloc has failed. */
+  sqlite3ExprDelete(db, pExpr);
+  sqlite3ExprListDelete(db, pList);
+  return 0;
 }
-#endif /* SQLITE_OMIT_SUBQUERY */
 
 /*
-** Duplicate an 8-byte value
+** If the expression list pEList contains more than iLimit elements,
+** leave an error message in pParse.
 */
-static char *dup8bytes(Vdbe *v, const char *in){
-  char *out = sqlite3DbMallocRaw(sqlite3VdbeDb(v), 8);
-  if( out ){
-    memcpy(out, in, 8);
+SQLITE_PRIVATE void sqlite3ExprListCheckLength(
+  Parse *pParse,
+  ExprList *pEList,
+  const char *zObject
+){
+  int mx = pParse->db->aLimit[SQLITE_LIMIT_COLUMN];
+  testcase( pEList && pEList->nExpr==mx );
+  testcase( pEList && pEList->nExpr==mx+1 );
+  if( pEList && pEList->nExpr>mx ){
+    sqlite3ErrorMsg(pParse, "too many columns in %s", zObject);
   }
-  return out;
 }
 
 /*
-** Generate an instruction that will put the floating point
-** value described by z[0..n-1] into register iMem.
-**
-** The z[] string will probably not be zero-terminated.  But the 
-** z[n] character is guaranteed to be something that does not look
-** like the continuation of the number.
+** Delete an entire expression list.
 */
-static void codeReal(Vdbe *v, const char *z, int n, int negateFlag, int iMem){
-  assert( z || v==0 || sqlite3VdbeDb(v)->mallocFailed );
-  if( z ){
-    double value;
-    char *zV;
-    assert( !isdigit(z[n]) );
-    sqlite3AtoF(z, &value);
-    if( negateFlag ) value = -value;
-    zV = dup8bytes(v, (char*)&value);
-    sqlite3VdbeAddOp4(v, OP_Real, 0, iMem, 0, zV, P4_REAL);
+SQLITE_PRIVATE void sqlite3ExprListDelete(sqlite3 *db, ExprList *pList){
+  int i;
+  struct ExprList_item *pItem;
+  if( pList==0 ) return;
+  assert( pList->a!=0 || (pList->nExpr==0 && pList->nAlloc==0) );
+  assert( pList->nExpr<=pList->nAlloc );
+  for(pItem=pList->a, i=0; inExpr; i++, pItem++){
+    sqlite3ExprDelete(db, pItem->pExpr);
+    sqlite3DbFree(db, pItem->zName);
   }
+  sqlite3DbFree(db, pList->a);
+  sqlite3DbFree(db, pList);
 }
 
-
 /*
-** Generate an instruction that will put the integer describe by
-** text z[0..n-1] into register iMem.
+** These routines are Walker callbacks.  Walker.u.pi is a pointer
+** to an integer.  These routines are checking an expression to see
+** if it is a constant.  Set *Walker.u.pi to 0 if the expression is
+** not constant.
+**
+** These callback routines are used to implement the following:
+**
+**     sqlite3ExprIsConstant()
+**     sqlite3ExprIsConstantNotJoin()
+**     sqlite3ExprIsConstantOrFunction()
 **
-** The z[] string will probably not be zero-terminated.  But the 
-** z[n] character is guaranteed to be something that does not look
-** like the continuation of the number.
 */
-static void codeInteger(Vdbe *v, const char *z, int n, int negFlag, int iMem){
-  assert( z || v==0 || sqlite3VdbeDb(v)->mallocFailed );
-  if( z ){
-    int i;
-    assert( !isdigit(z[n]) );
-    if( sqlite3GetInt32(z, &i) ){
-      if( negFlag ) i = -i;
-      sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
-    }else if( sqlite3FitsIn64Bits(z, negFlag) ){
-      i64 value;
-      char *zV;
-      sqlite3Atoi64(z, &value);
-      if( negFlag ) value = -value;
-      zV = dup8bytes(v, (char*)&value);
-      sqlite3VdbeAddOp4(v, OP_Int64, 0, iMem, 0, zV, P4_INT64);
-    }else{
-      codeReal(v, z, n, negFlag, iMem);
-    }
+static int exprNodeIsConstant(Walker *pWalker, Expr *pExpr){
+
+  /* If pWalker->u.i is 3 then any term of the expression that comes from
+  ** the ON or USING clauses of a join disqualifies the expression
+  ** from being considered constant. */
+  if( pWalker->u.i==3 && ExprHasAnyProperty(pExpr, EP_FromJoin) ){
+    pWalker->u.i = 0;
+    return WRC_Abort;
+  }
+
+  switch( pExpr->op ){
+    /* Consider functions to be constant if all their arguments are constant
+    ** and pWalker->u.i==2 */
+    case TK_FUNCTION:
+      if( pWalker->u.i==2 ) return 0;
+      /* Fall through */
+    case TK_ID:
+    case TK_COLUMN:
+    case TK_DOT:
+    case TK_AGG_FUNCTION:
+    case TK_AGG_COLUMN:
+#ifndef SQLITE_OMIT_SUBQUERY
+    case TK_SELECT:
+    case TK_EXISTS:
+      testcase( pExpr->op==TK_SELECT );
+      testcase( pExpr->op==TK_EXISTS );
+#endif
+      testcase( pExpr->op==TK_ID );
+      testcase( pExpr->op==TK_COLUMN );
+      testcase( pExpr->op==TK_DOT );
+      testcase( pExpr->op==TK_AGG_FUNCTION );
+      testcase( pExpr->op==TK_AGG_COLUMN );
+      pWalker->u.i = 0;
+      return WRC_Abort;
+    default:
+      return WRC_Continue;
   }
 }
+static int selectNodeIsConstant(Walker *pWalker, Select *pSelect){
+  pWalker->u.i = 0;
+  return WRC_Abort;
+}
+static int exprIsConst(Expr *p, int initFlag){
+  Walker w;
+  w.u.i = initFlag;
+  w.xExprCallback = exprNodeIsConstant;
+  w.xSelectCallback = selectNodeIsConstant;
+  sqlite3WalkExpr(&w, p);
+  return w.u.i;
+}
 
+/*
+** Walk an expression tree.  Return 1 if the expression is constant
+** and 0 if it involves variables or function calls.
+**
+** For the purposes of this function, a double-quoted string (ex: "abc")
+** is considered a variable but a single-quoted string (ex: 'abc') is
+** a constant.
+*/
+SQLITE_PRIVATE int sqlite3ExprIsConstant(Expr *p){
+  return exprIsConst(p, 1);
+}
 
 /*
-** Generate code that will extract the iColumn-th column from
-** table pTab and store the column value in register iReg.
-** There is an open cursor to pTab in 
-** iTable.  If iColumn<0 then code is generated that extracts the rowid.
+** Walk an expression tree.  Return 1 if the expression is constant
+** that does no originate from the ON or USING clauses of a join.
+** Return 0 if it involves variables or function calls or terms from
+** an ON or USING clause.
 */
-SQLITE_PRIVATE void sqlite3ExprCodeGetColumn(
-  Vdbe *v,         /* The VM being created */
-  Table *pTab,     /* Description of the table we are reading from */
-  int iColumn,     /* Index of the table column */
-  int iTable,      /* The cursor pointing to the table */
-  int iReg         /* Store results here */
-){
-  if( iColumn<0 ){
-    int op = (pTab && IsVirtual(pTab)) ? OP_VRowid : OP_Rowid;
-    sqlite3VdbeAddOp2(v, op, iTable, iReg);
-  }else if( pTab==0 ){
-    sqlite3VdbeAddOp3(v, OP_Column, iTable, iColumn, iReg);
-  }else{
-    int op = IsVirtual(pTab) ? OP_VColumn : OP_Column;
-    sqlite3VdbeAddOp3(v, op, iTable, iColumn, iReg);
-    sqlite3ColumnDefault(v, pTab, iColumn);
-#ifndef SQLITE_OMIT_FLOATING_POINT
-    if( pTab->aCol[iColumn].affinity==SQLITE_AFF_REAL ){
-      sqlite3VdbeAddOp1(v, OP_RealAffinity, iReg);
-    }
-#endif
-  }
+SQLITE_PRIVATE int sqlite3ExprIsConstantNotJoin(Expr *p){
+  return exprIsConst(p, 3);
 }
 
 /*
-** Generate code into the current Vdbe to evaluate the given
-** expression.  Attempt to store the results in register "target".
-** Return the register where results are stored.
+** Walk an expression tree.  Return 1 if the expression is constant
+** or a function call with constant arguments.  Return and 0 if there
+** are any variables.
 **
-** With this routine, there is no guaranteed that results will
-** be stored in target.  The result might be stored in some other
-** register if it is convenient to do so.  The calling function
-** must check the return code and move the results to the desired
-** register.
+** For the purposes of this function, a double-quoted string (ex: "abc")
+** is considered a variable but a single-quoted string (ex: 'abc') is
+** a constant.
 */
-static int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target){
-  Vdbe *v = pParse->pVdbe;  /* The VM under construction */
-  int op;                   /* The opcode being coded */
-  int inReg = target;       /* Results stored in register inReg */
-  int regFree1 = 0;         /* If non-zero free this temporary register */
-  int regFree2 = 0;         /* If non-zero free this temporary register */
-  int r1, r2, r3;           /* Various register numbers */
-
-  assert( v!=0 || pParse->db->mallocFailed );
-  assert( target>0 && target<=pParse->nMem );
-  if( v==0 ) return 0;
+SQLITE_PRIVATE int sqlite3ExprIsConstantOrFunction(Expr *p){
+  return exprIsConst(p, 2);
+}
 
-  if( pExpr==0 ){
-    op = TK_NULL;
-  }else{
-    op = pExpr->op;
+/*
+** If the expression p codes a constant integer that is small enough
+** to fit in a 32-bit integer, return 1 and put the value of the integer
+** in *pValue.  If the expression is not an integer or if it is too big
+** to fit in a signed 32-bit integer, return 0 and leave *pValue unchanged.
+*/
+SQLITE_PRIVATE int sqlite3ExprIsInteger(Expr *p, int *pValue){
+  int rc = 0;
+  if( p->flags & EP_IntValue ){
+    *pValue = p->iTable;
+    return 1;
   }
-  switch( op ){
-    case TK_AGG_COLUMN: {
-      AggInfo *pAggInfo = pExpr->pAggInfo;
-      struct AggInfo_col *pCol = &pAggInfo->aCol[pExpr->iAgg];
-      if( !pAggInfo->directMode ){
-        assert( pCol->iMem>0 );
-        inReg = pCol->iMem;
-        break;
-      }else if( pAggInfo->useSortingIdx ){
-        sqlite3VdbeAddOp3(v, OP_Column, pAggInfo->sortingIdx,
-                              pCol->iSorterColumn, target);
-        break;
-      }
-      /* Otherwise, fall thru into the TK_COLUMN case */
-    }
-    case TK_COLUMN: {
-      if( pExpr->iTable<0 ){
-        /* This only happens when coding check constraints */
-        assert( pParse->ckBase>0 );
-        inReg = pExpr->iColumn + pParse->ckBase;
-      }else{
-        sqlite3ExprCodeGetColumn(v, pExpr->pTab,
-                                 pExpr->iColumn, pExpr->iTable, target);
-      }
-      break;
-    }
+  switch( p->op ){
     case TK_INTEGER: {
-      codeInteger(v, (char*)pExpr->token.z, pExpr->token.n, 0, target);
-      break;
-    }
-    case TK_FLOAT: {
-      codeReal(v, (char*)pExpr->token.z, pExpr->token.n, 0, target);
-      break;
-    }
-    case TK_STRING: {
-      sqlite3DequoteExpr(pParse->db, pExpr);
-      sqlite3VdbeAddOp4(v,OP_String8, 0, target, 0,
-                        (char*)pExpr->token.z, pExpr->token.n);
-      break;
-    }
-    case TK_NULL: {
-      sqlite3VdbeAddOp2(v, OP_Null, 0, target);
+      rc = sqlite3GetInt32((char*)p->token.z, pValue);
       break;
     }
-#ifndef SQLITE_OMIT_BLOB_LITERAL
-    case TK_BLOB: {
-      int n;
-      const char *z;
-      char *zBlob;
-      assert( pExpr->token.n>=3 );
-      assert( pExpr->token.z[0]=='x' || pExpr->token.z[0]=='X' );
-      assert( pExpr->token.z[1]=='\'' );
-      assert( pExpr->token.z[pExpr->token.n-1]=='\'' );
-      n = pExpr->token.n - 3;
-      z = (char*)pExpr->token.z + 2;
-      zBlob = sqlite3HexToBlob(sqlite3VdbeDb(v), z, n);
-      sqlite3VdbeAddOp4(v, OP_Blob, n/2, target, 0, zBlob, P4_DYNAMIC);
+    case TK_UPLUS: {
+      rc = sqlite3ExprIsInteger(p->pLeft, pValue);
       break;
     }
-#endif
-    case TK_VARIABLE: {
-      sqlite3VdbeAddOp2(v, OP_Variable, pExpr->iTable, target);
-      if( pExpr->token.n>1 ){
-        sqlite3VdbeChangeP4(v, -1, (char*)pExpr->token.z, pExpr->token.n);
+    case TK_UMINUS: {
+      int v;
+      if( sqlite3ExprIsInteger(p->pLeft, &v) ){
+        *pValue = -v;
+        rc = 1;
       }
       break;
     }
-    case TK_REGISTER: {
-      inReg = pExpr->iTable;
-      break;
-    }
-#ifndef SQLITE_OMIT_CAST
-    case TK_CAST: {
-      /* Expressions of the form:   CAST(pLeft AS token) */
-      int aff, to_op;
-      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
-      aff = sqlite3AffinityType(&pExpr->token);
-      to_op = aff - SQLITE_AFF_TEXT + OP_ToText;
-      assert( to_op==OP_ToText    || aff!=SQLITE_AFF_TEXT    );
-      assert( to_op==OP_ToBlob    || aff!=SQLITE_AFF_NONE    );
-      assert( to_op==OP_ToNumeric || aff!=SQLITE_AFF_NUMERIC );
-      assert( to_op==OP_ToInt     || aff!=SQLITE_AFF_INTEGER );
-      assert( to_op==OP_ToReal    || aff!=SQLITE_AFF_REAL    );
-      sqlite3VdbeAddOp1(v, to_op, inReg);
-      break;
-    }
-#endif /* SQLITE_OMIT_CAST */
-    case TK_LT:
-    case TK_LE:
-    case TK_GT:
-    case TK_GE:
-    case TK_NE:
-    case TK_EQ: {
-      assert( TK_LT==OP_Lt );
-      assert( TK_LE==OP_Le );
-      assert( TK_GT==OP_Gt );
-      assert( TK_GE==OP_Ge );
-      assert( TK_EQ==OP_Eq );
-      assert( TK_NE==OP_Ne );
-      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
-      r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
-      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
-                  r1, r2, inReg, SQLITE_STOREP2);
-      break;
-    }
-    case TK_AND:
-    case TK_OR:
-    case TK_PLUS:
-    case TK_STAR:
-    case TK_MINUS:
-    case TK_REM:
-    case TK_BITAND:
-    case TK_BITOR:
-    case TK_SLASH:
-    case TK_LSHIFT:
-    case TK_RSHIFT: 
-    case TK_CONCAT: {
-      assert( TK_AND==OP_And );
-      assert( TK_OR==OP_Or );
-      assert( TK_PLUS==OP_Add );
-      assert( TK_MINUS==OP_Subtract );
-      assert( TK_REM==OP_Remainder );
-      assert( TK_BITAND==OP_BitAnd );
-      assert( TK_BITOR==OP_BitOr );
-      assert( TK_SLASH==OP_Divide );
-      assert( TK_LSHIFT==OP_ShiftLeft );
-      assert( TK_RSHIFT==OP_ShiftRight );
-      assert( TK_CONCAT==OP_Concat );
-      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
-      r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
-      sqlite3VdbeAddOp3(v, op, r2, r1, target);
-      break;
-    }
-    case TK_UMINUS: {
-      Expr *pLeft = pExpr->pLeft;
-      assert( pLeft );
-      if( pLeft->op==TK_FLOAT || pLeft->op==TK_INTEGER ){
-        Token *p = &pLeft->token;
-        if( pLeft->op==TK_FLOAT ){
-          codeReal(v, (char*)p->z, p->n, 1, target);
-        }else{
-          codeInteger(v, (char*)p->z, p->n, 1, target);
-        }
-      }else{
-        regFree1 = r1 = sqlite3GetTempReg(pParse);
-        sqlite3VdbeAddOp2(v, OP_Integer, 0, r1);
-        r2 = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
-        sqlite3VdbeAddOp3(v, OP_Subtract, r2, r1, target);
-      }
-      inReg = target;
-      break;
-    }
-    case TK_BITNOT:
-    case TK_NOT: {
-      assert( TK_BITNOT==OP_BitNot );
-      assert( TK_NOT==OP_Not );
-      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
-      sqlite3VdbeAddOp1(v, op, inReg);
-      break;
-    }
-    case TK_ISNULL:
-    case TK_NOTNULL: {
-      int addr;
-      assert( TK_ISNULL==OP_IsNull );
-      assert( TK_NOTNULL==OP_NotNull );
-      sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
-      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
-      addr = sqlite3VdbeAddOp1(v, op, r1);
-      sqlite3VdbeAddOp2(v, OP_AddImm, target, -1);
-      sqlite3VdbeJumpHere(v, addr);
-      break;
-    }
-    case TK_AGG_FUNCTION: {
-      AggInfo *pInfo = pExpr->pAggInfo;
-      if( pInfo==0 ){
-        sqlite3ErrorMsg(pParse, "misuse of aggregate: %T",
-            &pExpr->span);
-      }else{
-        inReg = pInfo->aFunc[pExpr->iAgg].iMem;
-      }
-      break;
-    }
-    case TK_CONST_FUNC:
-    case TK_FUNCTION: {
-      ExprList *pList = pExpr->pList;
-      int nExpr = pList ? pList->nExpr : 0;
-      FuncDef *pDef;
-      int nId;
-      const char *zId;
-      int constMask = 0;
-      int i;
-      sqlite3 *db = pParse->db;
-      u8 enc = ENC(db);
-      CollSeq *pColl = 0;
+    default: break;
+  }
+  if( rc ){
+    p->op = TK_INTEGER;
+    p->flags |= EP_IntValue;
+    p->iTable = *pValue;
+  }
+  return rc;
+}
 
-      zId = (char*)pExpr->token.z;
-      nId = pExpr->token.n;
-      pDef = sqlite3FindFunction(pParse->db, zId, nId, nExpr, enc, 0);
-      assert( pDef!=0 );
-      if( pList ){
-        nExpr = pList->nExpr;
-        r1 = sqlite3GetTempRange(pParse, nExpr);
-        sqlite3ExprCodeExprList(pParse, pList, r1);
-      }else{
-        nExpr = r1 = 0;
-      }
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-      /* Possibly overload the function if the first argument is
-      ** a virtual table column.
-      **
-      ** For infix functions (LIKE, GLOB, REGEXP, and MATCH) use the
-      ** second argument, not the first, as the argument to test to
-      ** see if it is a column in a virtual table.  This is done because
-      ** the left operand of infix functions (the operand we want to
-      ** control overloading) ends up as the second argument to the
-      ** function.  The expression "A glob B" is equivalent to 
-      ** "glob(B,A).  We want to use the A in "A glob B" to test
-      ** for function overloading.  But we use the B term in "glob(B,A)".
-      */
-      if( nExpr>=2 && (pExpr->flags & EP_InfixFunc) ){
-        pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[1].pExpr);
-      }else if( nExpr>0 ){
-        pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[0].pExpr);
-      }
+/*
+** Return TRUE if the given string is a row-id column name.
+*/
+SQLITE_PRIVATE int sqlite3IsRowid(const char *z){
+  if( sqlite3StrICmp(z, "_ROWID_")==0 ) return 1;
+  if( sqlite3StrICmp(z, "ROWID")==0 ) return 1;
+  if( sqlite3StrICmp(z, "OID")==0 ) return 1;
+  return 0;
+}
+
+#ifdef SQLITE_TEST
+  int sqlite3_enable_in_opt = 1;
+#else
+  #define sqlite3_enable_in_opt 1
 #endif
-      for(i=0; ia[i].pExpr) ){
-          constMask |= (1<needCollSeq && !pColl ){
-          pColl = sqlite3ExprCollSeq(pParse, pList->a[i].pExpr);
-        }
-      }
-      if( pDef->needCollSeq ){
-        if( !pColl ) pColl = pParse->db->pDfltColl; 
-        sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ);
-      }
-      sqlite3VdbeAddOp4(v, OP_Function, constMask, r1, target,
-                        (char*)pDef, P4_FUNCDEF);
-      sqlite3VdbeChangeP5(v, nExpr);
-      if( nExpr ){
-        sqlite3ReleaseTempRange(pParse, r1, nExpr);
-      }
-      break;
-    }
+
+/*
+** Return true if the IN operator optimization is enabled and
+** the SELECT statement p exists and is of the
+** simple form:
+**
+**     SELECT  FROM 
      
+**
+** If this is the case, it may be possible to use an existing table
+** or index instead of generating an epheremal table.
+*/
 #ifndef SQLITE_OMIT_SUBQUERY
-    case TK_EXISTS:
-    case TK_SELECT: {
-      if( pExpr->iColumn==0 ){
-        sqlite3CodeSubselect(pParse, pExpr);
-      }
-      inReg = pExpr->iColumn;
-      break;
-    }
-    case TK_IN: {
-      int j1, j2, j3, j4, j5;
-      char affinity;
-      int eType;
+static int isCandidateForInOpt(Select *p){
+  SrcList *pSrc;
+  ExprList *pEList;
+  Table *pTab;
+  if( !sqlite3_enable_in_opt ) return 0; /* IN optimization must be enabled */
+  if( p==0 ) return 0;                   /* right-hand side of IN is SELECT */
+  if( p->pPrior ) return 0;              /* Not a compound SELECT */
+  if( p->selFlags & (SF_Distinct|SF_Aggregate) ){
+      return 0; /* No DISTINCT keyword and no aggregate functions */
+  }
+  if( p->pGroupBy ) return 0;            /* Has no GROUP BY clause */
+  if( p->pLimit ) return 0;              /* Has no LIMIT clause */
+  if( p->pOffset ) return 0;
+  if( p->pWhere ) return 0;              /* Has no WHERE clause */
+  pSrc = p->pSrc;
+  if( pSrc==0 ) return 0;                /* A single table in the FROM clause */
+  if( pSrc->nSrc!=1 ) return 0;
+  if( pSrc->a[0].pSelect ) return 0;     /* FROM clause is not a subquery */
+  pTab = pSrc->a[0].pTab;
+  if( pTab==0 ) return 0;
+  if( pTab->pSelect ) return 0;          /* FROM clause is not a view */
+  if( IsVirtual(pTab) ) return 0;        /* FROM clause not a virtual table */
+  pEList = p->pEList;
+  if( pEList->nExpr!=1 ) return 0;       /* One column in the result set */
+  if( pEList->a[0].pExpr->op!=TK_COLUMN ) return 0; /* Result is a column */
+  return 1;
+}
+#endif /* SQLITE_OMIT_SUBQUERY */
 
-      eType = sqlite3FindInIndex(pParse, pExpr, 0);
+/*
+** This function is used by the implementation of the IN (...) operator.
+** It's job is to find or create a b-tree structure that may be used
+** either to test for membership of the (...) set or to iterate through
+** its members, skipping duplicates.
+**
+** The cursor opened on the structure (database table, database index 
+** or ephermal table) is stored in pX->iTable before this function returns.
+** The returned value indicates the structure type, as follows:
+**
+**   IN_INDEX_ROWID - The cursor was opened on a database table.
+**   IN_INDEX_INDEX - The cursor was opened on a database index.
+**   IN_INDEX_EPH -   The cursor was opened on a specially created and
+**                    populated epheremal table.
+**
+** An existing structure may only be used if the SELECT is of the simple
+** form:
+**
+**     SELECT  FROM 
      
+**
+** If prNotFound parameter is 0, then the structure will be used to iterate
+** through the set members, skipping any duplicates. In this case an
+** epheremal table must be used unless the selected  is guaranteed
+** to be unique - either because it is an INTEGER PRIMARY KEY or it
+** is unique by virtue of a constraint or implicit index.
+**
+** If the prNotFound parameter is not 0, then the structure will be used 
+** for fast set membership tests. In this case an epheremal table must 
+** be used unless  is an INTEGER PRIMARY KEY or an index can 
+** be found with  as its left-most column.
+**
+** When the structure is being used for set membership tests, the user
+** needs to know whether or not the structure contains an SQL NULL 
+** value in order to correctly evaluate expressions like "X IN (Y, Z)".
+** If there is a chance that the structure may contain a NULL value at
+** runtime, then a register is allocated and the register number written
+** to *prNotFound. If there is no chance that the structure contains a
+** NULL value, then *prNotFound is left unchanged.
+**
+** If a register is allocated and its location stored in *prNotFound, then
+** its initial value is NULL. If the structure does not remain constant
+** for the duration of the query (i.e. the set is a correlated sub-select), 
+** the value of the allocated register is reset to NULL each time the 
+** structure is repopulated. This allows the caller to use vdbe code 
+** equivalent to the following:
+**
+**   if( register==NULL ){
+**     has_null = 
+**     register = 1
+**   }
+**
+** in order to avoid running the 
+** test more often than is necessary.
+*/
+#ifndef SQLITE_OMIT_SUBQUERY
+SQLITE_PRIVATE int sqlite3FindInIndex(Parse *pParse, Expr *pX, int *prNotFound){
+  Select *p;
+  int eType = 0;
+  int iTab = pParse->nTab++;
+  int mustBeUnique = !prNotFound;
 
-      /* Figure out the affinity to use to create a key from the results
-      ** of the expression. affinityStr stores a static string suitable for
-      ** P4 of OP_MakeRecord.
-      */
-      affinity = comparisonAffinity(pExpr);
+  /* The follwing if(...) expression is true if the SELECT is of the 
+  ** simple form:
+  **
+  **     SELECT  FROM 
      
+  **
+  ** If this is the case, it may be possible to use an existing table
+  ** or index instead of generating an epheremal table.
+  */
+  p = pX->pSelect;
+  if( isCandidateForInOpt(p) ){
+    sqlite3 *db = pParse->db;
+    Index *pIdx;
+    Expr *pExpr = p->pEList->a[0].pExpr;
+    int iCol = pExpr->iColumn;
+    Vdbe *v = sqlite3GetVdbe(pParse);
 
-      sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
+    /* This function is only called from two places. In both cases the vdbe
+    ** has already been allocated. So assume sqlite3GetVdbe() is always
+    ** successful here.
+    */
+    assert(v);
+    if( iCol<0 ){
+      int iMem = ++pParse->nMem;
+      int iAddr;
+      Table *pTab = p->pSrc->a[0].pTab;
+      int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+      sqlite3VdbeUsesBtree(v, iDb);
 
-      /* Code the  from " IN (...)". The temporary table
-      ** pExpr->iTable contains the values that make up the (...) set.
+      iAddr = sqlite3VdbeAddOp1(v, OP_If, iMem);
+      sqlite3VdbeAddOp2(v, OP_Integer, 1, iMem);
+
+      sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
+      eType = IN_INDEX_ROWID;
+
+      sqlite3VdbeJumpHere(v, iAddr);
+    }else{
+      /* The collation sequence used by the comparison. If an index is to 
+      ** be used in place of a temp-table, it must be ordered according
+      ** to this collation sequence.
       */
-      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
-      j1 = sqlite3VdbeAddOp1(v, OP_NotNull, r1);
-      sqlite3VdbeAddOp2(v, OP_Null, 0, target);
-      j2  = sqlite3VdbeAddOp0(v, OP_Goto);
-      sqlite3VdbeJumpHere(v, j1);
-      if( eType==IN_INDEX_ROWID ){
-        j3 = sqlite3VdbeAddOp3(v, OP_MustBeInt, r1, 0, 1);
-        j4 = sqlite3VdbeAddOp3(v, OP_NotExists, pExpr->iTable, 0, r1);
-        j5 = sqlite3VdbeAddOp0(v, OP_Goto);
-        sqlite3VdbeJumpHere(v, j3);
-        sqlite3VdbeJumpHere(v, j4);
-      }else{
-        r2 = regFree2 = sqlite3GetTempReg(pParse);
-        sqlite3VdbeAddOp4(v, OP_MakeRecord, r1, 1, r2, &affinity, 1);
-        j5 = sqlite3VdbeAddOp3(v, OP_Found, pExpr->iTable, 0, r2);
-      }
-      sqlite3VdbeAddOp2(v, OP_AddImm, target, -1);
-      sqlite3VdbeJumpHere(v, j2);
-      sqlite3VdbeJumpHere(v, j5);
-      break;
-    }
-#endif
-    /*
-    **    x BETWEEN y AND z
-    **
-    ** This is equivalent to
-    **
-    **    x>=y AND x<=z
-    **
-    ** X is stored in pExpr->pLeft.
-    ** Y is stored in pExpr->pList->a[0].pExpr.
-    ** Z is stored in pExpr->pList->a[1].pExpr.
-    */
-    case TK_BETWEEN: {
-      Expr *pLeft = pExpr->pLeft;
-      struct ExprList_item *pLItem = pExpr->pList->a;
-      Expr *pRight = pLItem->pExpr;
+      CollSeq *pReq = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pExpr);
 
-      r1 = sqlite3ExprCodeTemp(pParse, pLeft, ®Free1);
-      r2 = sqlite3ExprCodeTemp(pParse, pRight, ®Free2);
-      r3 = sqlite3GetTempReg(pParse);
-      codeCompare(pParse, pLeft, pRight, OP_Ge,
-                  r1, r2, r3, SQLITE_STOREP2);
-      pLItem++;
-      pRight = pLItem->pExpr;
-      sqlite3ReleaseTempReg(pParse, regFree2);
-      r2 = sqlite3ExprCodeTemp(pParse, pRight, ®Free2);
-      codeCompare(pParse, pLeft, pRight, OP_Le, r1, r2, r2, SQLITE_STOREP2);
-      sqlite3VdbeAddOp3(v, OP_And, r3, r2, target);
-      sqlite3ReleaseTempReg(pParse, r3);
-      break;
-    }
-    case TK_UPLUS: {
-      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
-      break;
-    }
+      /* Check that the affinity that will be used to perform the 
+      ** comparison is the same as the affinity of the column. If
+      ** it is not, it is not possible to use any index.
+      */
+      Table *pTab = p->pSrc->a[0].pTab;
+      char aff = comparisonAffinity(pX);
+      int affinity_ok = (pTab->aCol[iCol].affinity==aff||aff==SQLITE_AFF_NONE);
 
-    /*
-    ** Form A:
-    **   CASE x WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END
-    **
-    ** Form B:
-    **   CASE WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END
-    **
-    ** Form A is can be transformed into the equivalent form B as follows:
-    **   CASE WHEN x=e1 THEN r1 WHEN x=e2 THEN r2 ...
-    **        WHEN x=eN THEN rN ELSE y END
-    **
-    ** X (if it exists) is in pExpr->pLeft.
-    ** Y is in pExpr->pRight.  The Y is also optional.  If there is no
-    ** ELSE clause and no other term matches, then the result of the
-    ** exprssion is NULL.
-    ** Ei is in pExpr->pList->a[i*2] and Ri is pExpr->pList->a[i*2+1].
-    **
-    ** The result of the expression is the Ri for the first matching Ei,
-    ** or if there is no matching Ei, the ELSE term Y, or if there is
-    ** no ELSE term, NULL.
-    */
-    case TK_CASE: {
-      int endLabel;                     /* GOTO label for end of CASE stmt */
-      int nextCase;                     /* GOTO label for next WHEN clause */
-      int nExpr;                        /* 2x number of WHEN terms */
-      int i;                            /* Loop counter */
-      ExprList *pEList;                 /* List of WHEN terms */
-      struct ExprList_item *aListelem;  /* Array of WHEN terms */
-      Expr opCompare;                   /* The X==Ei expression */
-      Expr cacheX;                      /* Cached expression X */
-      Expr *pX;                         /* The X expression */
-      Expr *pTest;                      /* X==Ei (form A) or just Ei (form B) */
+      for(pIdx=pTab->pIndex; pIdx && eType==0 && affinity_ok; pIdx=pIdx->pNext){
+        if( (pIdx->aiColumn[0]==iCol)
+         && (pReq==sqlite3FindCollSeq(db, ENC(db), pIdx->azColl[0], -1, 0))
+         && (!mustBeUnique || (pIdx->nColumn==1 && pIdx->onError!=OE_None))
+        ){
+          int iDb;
+          int iMem = ++pParse->nMem;
+          int iAddr;
+          char *pKey;
+  
+          pKey = (char *)sqlite3IndexKeyinfo(pParse, pIdx);
+          iDb = sqlite3SchemaToIndex(db, pIdx->pSchema);
+          sqlite3VdbeUsesBtree(v, iDb);
 
-      assert(pExpr->pList);
-      assert((pExpr->pList->nExpr % 2) == 0);
-      assert(pExpr->pList->nExpr > 0);
-      pEList = pExpr->pList;
-      aListelem = pEList->a;
-      nExpr = pEList->nExpr;
-      endLabel = sqlite3VdbeMakeLabel(v);
-      if( (pX = pExpr->pLeft)!=0 ){
-        cacheX = *pX;
-        cacheX.iTable = sqlite3ExprCodeTemp(pParse, pX, ®Free1);
-        cacheX.op = TK_REGISTER;
-        opCompare.op = TK_EQ;
-        opCompare.pLeft = &cacheX;
-        pTest = &opCompare;
-      }
-      for(i=0; inColumn);
+          sqlite3VdbeAddOp4(v, OP_OpenRead, iTab, pIdx->tnum, iDb,
+                               pKey,P4_KEYINFO_HANDOFF);
+          VdbeComment((v, "%s", pIdx->zName));
+          eType = IN_INDEX_INDEX;
+
+          sqlite3VdbeJumpHere(v, iAddr);
+          if( prNotFound && !pTab->aCol[iCol].notNull ){
+            *prNotFound = ++pParse->nMem;
+          }
         }
-        nextCase = sqlite3VdbeMakeLabel(v);
-        sqlite3ExprIfFalse(pParse, pTest, nextCase, SQLITE_JUMPIFNULL);
-        sqlite3ExprCode(pParse, aListelem[i+1].pExpr, target);
-        sqlite3VdbeAddOp2(v, OP_Goto, 0, endLabel);
-        sqlite3VdbeResolveLabel(v, nextCase);
-      }
-      if( pExpr->pRight ){
-        sqlite3ExprCode(pParse, pExpr->pRight, target);
-      }else{
-        sqlite3VdbeAddOp2(v, OP_Null, 0, target);
-      }
-      sqlite3VdbeResolveLabel(v, endLabel);
-      break;
-    }
-#ifndef SQLITE_OMIT_TRIGGER
-    case TK_RAISE: {
-      if( !pParse->trigStack ){
-        sqlite3ErrorMsg(pParse,
-                       "RAISE() may only be used within a trigger-program");
-        return 0;
-      }
-      if( pExpr->iColumn!=OE_Ignore ){
-         assert( pExpr->iColumn==OE_Rollback ||
-                 pExpr->iColumn == OE_Abort ||
-                 pExpr->iColumn == OE_Fail );
-         sqlite3DequoteExpr(pParse->db, pExpr);
-         sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, pExpr->iColumn, 0,
-                        (char*)pExpr->token.z, pExpr->token.n);
-      } else {
-         assert( pExpr->iColumn == OE_Ignore );
-         sqlite3VdbeAddOp2(v, OP_ContextPop, 0, 0);
-         sqlite3VdbeAddOp2(v, OP_Goto, 0, pParse->trigStack->ignoreJump);
-         VdbeComment((v, "raise(IGNORE)"));
       }
-      break;
     }
-#endif
   }
-  sqlite3ReleaseTempReg(pParse, regFree1);
-  sqlite3ReleaseTempReg(pParse, regFree2);
-  return inReg;
-}
 
-/*
-** Generate code to evaluate an expression and store the results
-** into a register.  Return the register number where the results
-** are stored.
-**
-** If the register is a temporary register that can be deallocated,
-** then write its number into *pReg.  If the result register is no
-** a temporary, then set *pReg to zero.
-*/
-SQLITE_PRIVATE int sqlite3ExprCodeTemp(Parse *pParse, Expr *pExpr, int *pReg){
-  int r1 = sqlite3GetTempReg(pParse);
-  int r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
-  if( r2==r1 ){
-    *pReg = r1;
+  if( eType==0 ){
+    int rMayHaveNull = 0;
+    eType = IN_INDEX_EPH;
+    if( prNotFound ){
+      *prNotFound = rMayHaveNull = ++pParse->nMem;
+    }else if( pX->pLeft->iColumn<0 && pX->pSelect==0 ){
+      eType = IN_INDEX_ROWID;
+    }
+    sqlite3CodeSubselect(pParse, pX, rMayHaveNull, eType==IN_INDEX_ROWID);
   }else{
-    sqlite3ReleaseTempReg(pParse, r1);
-    *pReg = 0;
+    pX->iTable = iTab;
   }
-  return r2;
+  return eType;
 }
+#endif
 
 /*
-** Generate code that will evaluate expression pExpr and store the
-** results in register target.  The results are guaranteed to appear
-** in register target.
+** Generate code for scalar subqueries used as an expression
+** and IN operators.  Examples:
+**
+**     (SELECT a FROM b)          -- subquery
+**     EXISTS (SELECT a FROM b)   -- EXISTS subquery
+**     x IN (4,5,11)              -- IN operator with list on right-hand side
+**     x IN (SELECT a FROM b)     -- IN operator with subquery on the right
+**
+** The pExpr parameter describes the expression that contains the IN
+** operator or subquery.
+**
+** If parameter isRowid is non-zero, then expression pExpr is guaranteed
+** to be of the form " IN (?, ?, ?)", where  is a reference
+** to some integer key column of a table B-Tree. In this case, use an
+** intkey B-Tree to store the set of IN(...) values instead of the usual
+** (slower) variable length keys B-Tree.
 */
-SQLITE_PRIVATE int sqlite3ExprCode(Parse *pParse, Expr *pExpr, int target){
-  int inReg;
+#ifndef SQLITE_OMIT_SUBQUERY
+SQLITE_PRIVATE void sqlite3CodeSubselect(
+  Parse *pParse, 
+  Expr *pExpr, 
+  int rMayHaveNull,
+  int isRowid
+){
+  int testAddr = 0;                       /* One-time test address */
+  Vdbe *v = sqlite3GetVdbe(pParse);
+  if( v==0 ) return;
 
-  assert( target>0 && target<=pParse->nMem );
-  inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
-  assert( pParse->pVdbe || pParse->db->mallocFailed );
-  if( inReg!=target && pParse->pVdbe ){
-    sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, inReg, target);
+
+  /* This code must be run in its entirety every time it is encountered
+  ** if any of the following is true:
+  **
+  **    *  The right-hand side is a correlated subquery
+  **    *  The right-hand side is an expression list containing variables
+  **    *  We are inside a trigger
+  **
+  ** If all of the above are false, then we can run this code just once
+  ** save the results, and reuse the same result on subsequent invocations.
+  */
+  if( !ExprHasAnyProperty(pExpr, EP_VarSelect) && !pParse->trigStack ){
+    int mem = ++pParse->nMem;
+    sqlite3VdbeAddOp1(v, OP_If, mem);
+    testAddr = sqlite3VdbeAddOp2(v, OP_Integer, 1, mem);
+    assert( testAddr>0 || pParse->db->mallocFailed );
   }
-  return target;
-}
 
-/*
-** Generate code that evalutes the given expression and puts the result
-** in register target.
+  switch( pExpr->op ){
+    case TK_IN: {
+      char affinity;
+      KeyInfo keyInfo;
+      int addr;        /* Address of OP_OpenEphemeral instruction */
+      Expr *pLeft = pExpr->pLeft;
+
+      if( rMayHaveNull ){
+        sqlite3VdbeAddOp2(v, OP_Null, 0, rMayHaveNull);
+      }
+
+      affinity = sqlite3ExprAffinity(pLeft);
+
+      /* Whether this is an 'x IN(SELECT...)' or an 'x IN()'
+      ** expression it is handled the same way. A virtual table is 
+      ** filled with single-field index keys representing the results
+      ** from the SELECT or the .
+      **
+      ** If the 'x' expression is a column value, or the SELECT...
+      ** statement returns a column value, then the affinity of that
+      ** column is used to build the index keys. If both 'x' and the
+      ** SELECT... statement are columns, then numeric affinity is used
+      ** if either column has NUMERIC or INTEGER affinity. If neither
+      ** 'x' nor the SELECT... statement are columns, then numeric affinity
+      ** is used.
+      */
+      pExpr->iTable = pParse->nTab++;
+      addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pExpr->iTable, !isRowid);
+      memset(&keyInfo, 0, sizeof(keyInfo));
+      keyInfo.nField = 1;
+
+      if( pExpr->pSelect ){
+        /* Case 1:     expr IN (SELECT ...)
+        **
+        ** Generate code to write the results of the select into the temporary
+        ** table allocated and opened above.
+        */
+        SelectDest dest;
+        ExprList *pEList;
+
+        assert( !isRowid );
+        sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
+        dest.affinity = (int)affinity;
+        assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
+        if( sqlite3Select(pParse, pExpr->pSelect, &dest) ){
+          return;
+        }
+        pEList = pExpr->pSelect->pEList;
+        if( pEList && pEList->nExpr>0 ){ 
+          keyInfo.aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft,
+              pEList->a[0].pExpr);
+        }
+      }else if( pExpr->pList ){
+        /* Case 2:     expr IN (exprlist)
+        **
+        ** For each expression, build an index key from the evaluation and
+        ** store it in the temporary table. If  is a column, then use
+        ** that columns affinity when building index keys. If  is not
+        ** a column, use numeric affinity.
+        */
+        int i;
+        ExprList *pList = pExpr->pList;
+        struct ExprList_item *pItem;
+        int r1, r2, r3;
+
+        if( !affinity ){
+          affinity = SQLITE_AFF_NONE;
+        }
+        keyInfo.aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
+
+        /* Loop through each expression in . */
+        r1 = sqlite3GetTempReg(pParse);
+        r2 = sqlite3GetTempReg(pParse);
+        sqlite3VdbeAddOp2(v, OP_Null, 0, r2);
+        for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){
+          Expr *pE2 = pItem->pExpr;
+
+          /* If the expression is not constant then we will need to
+          ** disable the test that was generated above that makes sure
+          ** this code only executes once.  Because for a non-constant
+          ** expression we need to rerun this code each time.
+          */
+          if( testAddr && !sqlite3ExprIsConstant(pE2) ){
+            sqlite3VdbeChangeToNoop(v, testAddr-1, 2);
+            testAddr = 0;
+          }
+
+          /* Evaluate the expression and insert it into the temp table */
+          pParse->disableColCache++;
+          r3 = sqlite3ExprCodeTarget(pParse, pE2, r1);
+          assert( pParse->disableColCache>0 );
+          pParse->disableColCache--;
+
+          if( isRowid ){
+            sqlite3VdbeAddOp2(v, OP_MustBeInt, r3, sqlite3VdbeCurrentAddr(v)+2);
+            sqlite3VdbeAddOp3(v, OP_Insert, pExpr->iTable, r2, r3);
+          }else{
+            sqlite3VdbeAddOp4(v, OP_MakeRecord, r3, 1, r2, &affinity, 1);
+            sqlite3ExprCacheAffinityChange(pParse, r3, 1);
+            sqlite3VdbeAddOp2(v, OP_IdxInsert, pExpr->iTable, r2);
+          }
+        }
+        sqlite3ReleaseTempReg(pParse, r1);
+        sqlite3ReleaseTempReg(pParse, r2);
+      }
+      if( !isRowid ){
+        sqlite3VdbeChangeP4(v, addr, (void *)&keyInfo, P4_KEYINFO);
+      }
+      break;
+    }
+
+    case TK_EXISTS:
+    case TK_SELECT: {
+      /* This has to be a scalar SELECT.  Generate code to put the
+      ** value of this select in a memory cell and record the number
+      ** of the memory cell in iColumn.
+      */
+      static const Token one = { (u8*)"1", 0, 1 };
+      Select *pSel;
+      SelectDest dest;
+
+      pSel = pExpr->pSelect;
+      sqlite3SelectDestInit(&dest, 0, ++pParse->nMem);
+      if( pExpr->op==TK_SELECT ){
+        dest.eDest = SRT_Mem;
+        sqlite3VdbeAddOp2(v, OP_Null, 0, dest.iParm);
+        VdbeComment((v, "Init subquery result"));
+      }else{
+        dest.eDest = SRT_Exists;
+        sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iParm);
+        VdbeComment((v, "Init EXISTS result"));
+      }
+      sqlite3ExprDelete(pParse->db, pSel->pLimit);
+      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, &one);
+      if( sqlite3Select(pParse, pSel, &dest) ){
+        return;
+      }
+      pExpr->iColumn = dest.iParm;
+      break;
+    }
+  }
+
+  if( testAddr ){
+    sqlite3VdbeJumpHere(v, testAddr-1);
+  }
+
+  return;
+}
+#endif /* SQLITE_OMIT_SUBQUERY */
+
+/*
+** Duplicate an 8-byte value
+*/
+static char *dup8bytes(Vdbe *v, const char *in){
+  char *out = sqlite3DbMallocRaw(sqlite3VdbeDb(v), 8);
+  if( out ){
+    memcpy(out, in, 8);
+  }
+  return out;
+}
+
+/*
+** Generate an instruction that will put the floating point
+** value described by z[0..n-1] into register iMem.
 **
-** Also make a copy of the expression results into another "cache" register
-** and modify the expression so that the next time it is evaluated,
-** the result is a copy of the cache register.
+** The z[] string will probably not be zero-terminated.  But the 
+** z[n] character is guaranteed to be something that does not look
+** like the continuation of the number.
+*/
+static void codeReal(Vdbe *v, const char *z, int n, int negateFlag, int iMem){
+  assert( z || v==0 || sqlite3VdbeDb(v)->mallocFailed );
+  if( z ){
+    double value;
+    char *zV;
+    assert( !isdigit(z[n]) );
+    sqlite3AtoF(z, &value);
+    if( sqlite3IsNaN(value) ){
+      sqlite3VdbeAddOp2(v, OP_Null, 0, iMem);
+    }else{
+      if( negateFlag ) value = -value;
+      zV = dup8bytes(v, (char*)&value);
+      sqlite3VdbeAddOp4(v, OP_Real, 0, iMem, 0, zV, P4_REAL);
+    }
+  }
+}
+
+
+/*
+** Generate an instruction that will put the integer describe by
+** text z[0..n-1] into register iMem.
 **
-** This routine is used for expressions that are used multiple 
-** times.  They are evaluated once and the results of the expression
-** are reused.
+** The z[] string will probably not be zero-terminated.  But the 
+** z[n] character is guaranteed to be something that does not look
+** like the continuation of the number.
 */
-SQLITE_PRIVATE int sqlite3ExprCodeAndCache(Parse *pParse, Expr *pExpr, int target){
-  Vdbe *v = pParse->pVdbe;
-  int inReg;
-  inReg = sqlite3ExprCode(pParse, pExpr, target);
-  assert( target>0 );
-  if( pExpr->op!=TK_REGISTER ){  
-    int iMem;
-    iMem = ++pParse->nMem;
-    sqlite3VdbeAddOp2(v, OP_Copy, inReg, iMem);
-    pExpr->iTable = iMem;
-    pExpr->op = TK_REGISTER;
+static void codeInteger(Vdbe *v, Expr *pExpr, int negFlag, int iMem){
+  const char *z;
+  if( pExpr->flags & EP_IntValue ){
+    int i = pExpr->iTable;
+    if( negFlag ) i = -i;
+    sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
+  }else if( (z = (char*)pExpr->token.z)!=0 ){
+    int i;
+    int n = pExpr->token.n;
+    assert( !isdigit(z[n]) );
+    if( sqlite3GetInt32(z, &i) ){
+      if( negFlag ) i = -i;
+      sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
+    }else if( sqlite3FitsIn64Bits(z, negFlag) ){
+      i64 value;
+      char *zV;
+      sqlite3Atoi64(z, &value);
+      if( negFlag ) value = -value;
+      zV = dup8bytes(v, (char*)&value);
+      sqlite3VdbeAddOp4(v, OP_Int64, 0, iMem, 0, zV, P4_INT64);
+    }else{
+      codeReal(v, z, n, negFlag, iMem);
+    }
   }
-  return inReg;
 }
 
 
 /*
-** Generate code that pushes the value of every element of the given
-** expression list into a sequence of registers beginning at target.
+** Generate code that will extract the iColumn-th column from
+** table pTab and store the column value in a register.  An effort
+** is made to store the column value in register iReg, but this is
+** not guaranteed.  The location of the column value is returned.
 **
-** Return the number of elements evaluated.
+** There must be an open cursor to pTab in iTable when this routine
+** is called.  If iColumn<0 then code is generated that extracts the rowid.
+**
+** This routine might attempt to reuse the value of the column that
+** has already been loaded into a register.  The value will always
+** be used if it has not undergone any affinity changes.  But if
+** an affinity change has occurred, then the cached value will only be
+** used if allowAffChng is true.
 */
-SQLITE_PRIVATE int sqlite3ExprCodeExprList(
-  Parse *pParse,     /* Parsing context */
-  ExprList *pList,   /* The expression list to be coded */
-  int target         /* Where to write results */
+SQLITE_PRIVATE int sqlite3ExprCodeGetColumn(
+  Parse *pParse,   /* Parsing and code generating context */
+  Table *pTab,     /* Description of the table we are reading from */
+  int iColumn,     /* Index of the table column */
+  int iTable,      /* The cursor pointing to the table */
+  int iReg,        /* Store results here */
+  int allowAffChng /* True if prior affinity changes are OK */
 ){
-  struct ExprList_item *pItem;
-  int i, n;
-  assert( pList!=0 || pParse->db->mallocFailed );
-  if( pList==0 ){
-    return 0;
+  Vdbe *v = pParse->pVdbe;
+  int i;
+  struct yColCache *p;
+
+  for(i=0, p=pParse->aColCache; inColCache; i++, p++){
+    if( p->iTable==iTable && p->iColumn==iColumn
+           && (!p->affChange || allowAffChng) ){
+#if 0
+      sqlite3VdbeAddOp0(v, OP_Noop);
+      VdbeComment((v, "OPT: tab%d.col%d -> r%d", iTable, iColumn, p->iReg));
+#endif
+      return p->iReg;
+    }
+  }  
+  assert( v!=0 );
+  if( iColumn<0 ){
+    int op = (pTab && IsVirtual(pTab)) ? OP_VRowid : OP_Rowid;
+    sqlite3VdbeAddOp2(v, op, iTable, iReg);
+  }else if( pTab==0 ){
+    sqlite3VdbeAddOp3(v, OP_Column, iTable, iColumn, iReg);
+  }else{
+    int op = IsVirtual(pTab) ? OP_VColumn : OP_Column;
+    sqlite3VdbeAddOp3(v, op, iTable, iColumn, iReg);
+    sqlite3ColumnDefault(v, pTab, iColumn);
+#ifndef SQLITE_OMIT_FLOATING_POINT
+    if( pTab->aCol[iColumn].affinity==SQLITE_AFF_REAL ){
+      sqlite3VdbeAddOp1(v, OP_RealAffinity, iReg);
+    }
+#endif
   }
-  assert( target>0 );
-  n = pList->nExpr;
-  for(pItem=pList->a, i=n; i>0; i--, pItem++){
-    sqlite3ExprCode(pParse, pItem->pExpr, target);
-    target++;
+  if( pParse->disableColCache==0 ){
+    i = pParse->iColCache;
+    p = &pParse->aColCache[i];
+    p->iTable = iTable;
+    p->iColumn = iColumn;
+    p->iReg = iReg;
+    p->affChange = 0;
+    i++;
+    if( i>=ArraySize(pParse->aColCache) ) i = 0;
+    if( i>pParse->nColCache ) pParse->nColCache = i;
+    pParse->iColCache = i;
   }
-  return n;
+  return iReg;
 }
 
 /*
-** Generate code for a boolean expression such that a jump is made
-** to the label "dest" if the expression is true but execution
-** continues straight thru if the expression is false.
+** Clear all column cache entries associated with the vdbe
+** cursor with cursor number iTable.
+*/
+SQLITE_PRIVATE void sqlite3ExprClearColumnCache(Parse *pParse, int iTable){
+  if( iTable<0 ){
+    pParse->nColCache = 0;
+    pParse->iColCache = 0;
+  }else{
+    int i;
+    for(i=0; inColCache; i++){
+      if( pParse->aColCache[i].iTable==iTable ){
+        testcase( i==pParse->nColCache-1 );
+        pParse->aColCache[i] = pParse->aColCache[--pParse->nColCache];
+        pParse->iColCache = pParse->nColCache;
+      }
+    }
+  }
+}
+
+/*
+** Record the fact that an affinity change has occurred on iCount
+** registers starting with iStart.
+*/
+SQLITE_PRIVATE void sqlite3ExprCacheAffinityChange(Parse *pParse, int iStart, int iCount){
+  int iEnd = iStart + iCount - 1;
+  int i;
+  for(i=0; inColCache; i++){
+    int r = pParse->aColCache[i].iReg;
+    if( r>=iStart && r<=iEnd ){
+      pParse->aColCache[i].affChange = 1;
+    }
+  }
+}
+
+/*
+** Generate code to move content from registers iFrom...iFrom+nReg-1
+** over to iTo..iTo+nReg-1. Keep the column cache up-to-date.
+*/
+SQLITE_PRIVATE void sqlite3ExprCodeMove(Parse *pParse, int iFrom, int iTo, int nReg){
+  int i;
+  if( iFrom==iTo ) return;
+  sqlite3VdbeAddOp3(pParse->pVdbe, OP_Move, iFrom, iTo, nReg);
+  for(i=0; inColCache; i++){
+    int x = pParse->aColCache[i].iReg;
+    if( x>=iFrom && xaColCache[i].iReg += iTo-iFrom;
+    }
+  }
+}
+
+/*
+** Generate code to copy content from registers iFrom...iFrom+nReg-1
+** over to iTo..iTo+nReg-1.
+*/
+SQLITE_PRIVATE void sqlite3ExprCodeCopy(Parse *pParse, int iFrom, int iTo, int nReg){
+  int i;
+  if( iFrom==iTo ) return;
+  for(i=0; ipVdbe, OP_Copy, iFrom+i, iTo+i);
+  }
+}
+
+/*
+** Return true if any register in the range iFrom..iTo (inclusive)
+** is used as part of the column cache.
+*/
+static int usedAsColumnCache(Parse *pParse, int iFrom, int iTo){
+  int i;
+  for(i=0; inColCache; i++){
+    int r = pParse->aColCache[i].iReg;
+    if( r>=iFrom && r<=iTo ) return 1;
+  }
+  return 0;
+}
+
+/*
+** Theres is a value in register iCurrent.  We ultimately want
+** the value to be in register iTarget.  It might be that
+** iCurrent and iTarget are the same register.
 **
-** If the expression evaluates to NULL (neither true nor false), then
-** take the jump if the jumpIfNull flag is SQLITE_JUMPIFNULL.
+** We are going to modify the value, so we need to make sure it
+** is not a cached register.  If iCurrent is a cached register,
+** then try to move the value over to iTarget.  If iTarget is a
+** cached register, then clear the corresponding cache line.
 **
-** This code depends on the fact that certain token values (ex: TK_EQ)
-** are the same as opcode values (ex: OP_Eq) that implement the corresponding
-** operation.  Special comments in vdbe.c and the mkopcodeh.awk script in
-** the make process cause these values to align.  Assert()s in the code
-** below verify that the numbers are aligned correctly.
+** Return the register that the value ends up in.
 */
-SQLITE_PRIVATE void sqlite3ExprIfTrue(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
-  Vdbe *v = pParse->pVdbe;
-  int op = 0;
-  int regFree1 = 0;
-  int regFree2 = 0;
-  int r1, r2;
+SQLITE_PRIVATE int sqlite3ExprWritableRegister(Parse *pParse, int iCurrent, int iTarget){
+  int i;
+  assert( pParse->pVdbe!=0 );
+  if( !usedAsColumnCache(pParse, iCurrent, iCurrent) ){
+    return iCurrent;
+  }
+  if( iCurrent!=iTarget ){
+    sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, iCurrent, iTarget);
+  }
+  for(i=0; inColCache; i++){
+    if( pParse->aColCache[i].iReg==iTarget ){
+      pParse->aColCache[i] = pParse->aColCache[--pParse->nColCache];
+      pParse->iColCache = pParse->nColCache;
+    }
+  }
+  return iTarget;
+}
 
-  assert( jumpIfNull==SQLITE_JUMPIFNULL || jumpIfNull==0 );
-  if( v==0 || pExpr==0 ) return;
-  op = pExpr->op;
+/*
+** If the last instruction coded is an ephemeral copy of any of
+** the registers in the nReg registers beginning with iReg, then
+** convert the last instruction from OP_SCopy to OP_Copy.
+*/
+SQLITE_PRIVATE void sqlite3ExprHardCopy(Parse *pParse, int iReg, int nReg){
+  int addr;
+  VdbeOp *pOp;
+  Vdbe *v;
+
+  v = pParse->pVdbe;
+  addr = sqlite3VdbeCurrentAddr(v);
+  pOp = sqlite3VdbeGetOp(v, addr-1);
+  assert( pOp || pParse->db->mallocFailed );
+  if( pOp && pOp->opcode==OP_SCopy && pOp->p1>=iReg && pOp->p1opcode = OP_Copy;
+  }
+}
+
+/*
+** Generate code to store the value of the iAlias-th alias in register
+** target.  The first time this is called, pExpr is evaluated to compute
+** the value of the alias.  The value is stored in an auxiliary register
+** and the number of that register is returned.  On subsequent calls,
+** the register number is returned without generating any code.
+**
+** Note that in order for this to work, code must be generated in the
+** same order that it is executed.
+**
+** Aliases are numbered starting with 1.  So iAlias is in the range
+** of 1 to pParse->nAlias inclusive.  
+**
+** pParse->aAlias[iAlias-1] records the register number where the value
+** of the iAlias-th alias is stored.  If zero, that means that the
+** alias has not yet been computed.
+*/
+static int codeAlias(Parse *pParse, int iAlias, Expr *pExpr){
+  sqlite3 *db = pParse->db;
+  int iReg;
+  if( pParse->aAlias==0 ){
+    pParse->aAlias = sqlite3DbMallocZero(db, 
+                                 sizeof(pParse->aAlias[0])*pParse->nAlias );
+    if( db->mallocFailed ) return 0;
+  }
+  assert( iAlias>0 && iAlias<=pParse->nAlias );
+  iReg = pParse->aAlias[iAlias-1];
+  if( iReg==0 ){
+    iReg = ++pParse->nMem;
+    sqlite3ExprCode(pParse, pExpr, iReg);
+    pParse->aAlias[iAlias-1] = iReg;
+  }
+  return iReg;
+}
+
+/*
+** Generate code into the current Vdbe to evaluate the given
+** expression.  Attempt to store the results in register "target".
+** Return the register where results are stored.
+**
+** With this routine, there is no guarantee that results will
+** be stored in target.  The result might be stored in some other
+** register if it is convenient to do so.  The calling function
+** must check the return code and move the results to the desired
+** register.
+*/
+SQLITE_PRIVATE int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target){
+  Vdbe *v = pParse->pVdbe;  /* The VM under construction */
+  int op;                   /* The opcode being coded */
+  int inReg = target;       /* Results stored in register inReg */
+  int regFree1 = 0;         /* If non-zero free this temporary register */
+  int regFree2 = 0;         /* If non-zero free this temporary register */
+  int r1, r2, r3, r4;       /* Various register numbers */
+  sqlite3 *db;
+
+  db = pParse->db;
+  assert( v!=0 || db->mallocFailed );
+  assert( target>0 && target<=pParse->nMem );
+  if( v==0 ) return 0;
+
+  if( pExpr==0 ){
+    op = TK_NULL;
+  }else{
+    op = pExpr->op;
+  }
   switch( op ){
-    case TK_AND: {
-      int d2 = sqlite3VdbeMakeLabel(v);
-      sqlite3ExprIfFalse(pParse, pExpr->pLeft, d2,jumpIfNull^SQLITE_JUMPIFNULL);
-      sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
-      sqlite3VdbeResolveLabel(v, d2);
+    case TK_AGG_COLUMN: {
+      AggInfo *pAggInfo = pExpr->pAggInfo;
+      struct AggInfo_col *pCol = &pAggInfo->aCol[pExpr->iAgg];
+      if( !pAggInfo->directMode ){
+        assert( pCol->iMem>0 );
+        inReg = pCol->iMem;
+        break;
+      }else if( pAggInfo->useSortingIdx ){
+        sqlite3VdbeAddOp3(v, OP_Column, pAggInfo->sortingIdx,
+                              pCol->iSorterColumn, target);
+        break;
+      }
+      /* Otherwise, fall thru into the TK_COLUMN case */
+    }
+    case TK_COLUMN: {
+      if( pExpr->iTable<0 ){
+        /* This only happens when coding check constraints */
+        assert( pParse->ckBase>0 );
+        inReg = pExpr->iColumn + pParse->ckBase;
+      }else{
+        testcase( (pExpr->flags & EP_AnyAff)!=0 );
+        inReg = sqlite3ExprCodeGetColumn(pParse, pExpr->pTab,
+                                 pExpr->iColumn, pExpr->iTable, target,
+                                 pExpr->flags & EP_AnyAff);
+      }
       break;
     }
-    case TK_OR: {
-      sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
-      sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
+    case TK_INTEGER: {
+      codeInteger(v, pExpr, 0, target);
       break;
     }
-    case TK_NOT: {
-      sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
+    case TK_FLOAT: {
+      codeReal(v, (char*)pExpr->token.z, pExpr->token.n, 0, target);
+      break;
+    }
+    case TK_STRING: {
+      sqlite3DequoteExpr(db, pExpr);
+      sqlite3VdbeAddOp4(v,OP_String8, 0, target, 0,
+                        (char*)pExpr->token.z, pExpr->token.n);
+      break;
+    }
+    case TK_NULL: {
+      sqlite3VdbeAddOp2(v, OP_Null, 0, target);
+      break;
+    }
+#ifndef SQLITE_OMIT_BLOB_LITERAL
+    case TK_BLOB: {
+      int n;
+      const char *z;
+      char *zBlob;
+      assert( pExpr->token.n>=3 );
+      assert( pExpr->token.z[0]=='x' || pExpr->token.z[0]=='X' );
+      assert( pExpr->token.z[1]=='\'' );
+      assert( pExpr->token.z[pExpr->token.n-1]=='\'' );
+      n = pExpr->token.n - 3;
+      z = (char*)pExpr->token.z + 2;
+      zBlob = sqlite3HexToBlob(sqlite3VdbeDb(v), z, n);
+      sqlite3VdbeAddOp4(v, OP_Blob, n/2, target, 0, zBlob, P4_DYNAMIC);
+      break;
+    }
+#endif
+    case TK_VARIABLE: {
+      sqlite3VdbeAddOp2(v, OP_Variable, pExpr->iTable, target);
+      if( pExpr->token.n>1 ){
+        sqlite3VdbeChangeP4(v, -1, (char*)pExpr->token.z, pExpr->token.n);
+      }
+      break;
+    }
+    case TK_REGISTER: {
+      inReg = pExpr->iTable;
+      break;
+    }
+    case TK_AS: {
+      inReg = codeAlias(pParse, pExpr->iTable, pExpr->pLeft);
+      break;
+    }
+#ifndef SQLITE_OMIT_CAST
+    case TK_CAST: {
+      /* Expressions of the form:   CAST(pLeft AS token) */
+      int aff, to_op;
+      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
+      aff = sqlite3AffinityType(&pExpr->token);
+      to_op = aff - SQLITE_AFF_TEXT + OP_ToText;
+      assert( to_op==OP_ToText    || aff!=SQLITE_AFF_TEXT    );
+      assert( to_op==OP_ToBlob    || aff!=SQLITE_AFF_NONE    );
+      assert( to_op==OP_ToNumeric || aff!=SQLITE_AFF_NUMERIC );
+      assert( to_op==OP_ToInt     || aff!=SQLITE_AFF_INTEGER );
+      assert( to_op==OP_ToReal    || aff!=SQLITE_AFF_REAL    );
+      testcase( to_op==OP_ToText );
+      testcase( to_op==OP_ToBlob );
+      testcase( to_op==OP_ToNumeric );
+      testcase( to_op==OP_ToInt );
+      testcase( to_op==OP_ToReal );
+      sqlite3VdbeAddOp1(v, to_op, inReg);
+      testcase( usedAsColumnCache(pParse, inReg, inReg) );
+      sqlite3ExprCacheAffinityChange(pParse, inReg, 1);
       break;
     }
+#endif /* SQLITE_OMIT_CAST */
     case TK_LT:
     case TK_LE:
     case TK_GT:
@@ -48454,38 +54823,749 @@ SQLITE_PRIVATE void sqlite3ExprIfTrue(Parse *pParse, Expr *pExpr, int dest, int
       assert( TK_GE==OP_Ge );
       assert( TK_EQ==OP_Eq );
       assert( TK_NE==OP_Ne );
+      testcase( op==TK_LT );
+      testcase( op==TK_LE );
+      testcase( op==TK_GT );
+      testcase( op==TK_GE );
+      testcase( op==TK_EQ );
+      testcase( op==TK_NE );
+      codeCompareOperands(pParse, pExpr->pLeft, &r1, ®Free1,
+                                  pExpr->pRight, &r2, ®Free2);
+      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
+                  r1, r2, inReg, SQLITE_STOREP2);
+      testcase( regFree1==0 );
+      testcase( regFree2==0 );
+      break;
+    }
+    case TK_AND:
+    case TK_OR:
+    case TK_PLUS:
+    case TK_STAR:
+    case TK_MINUS:
+    case TK_REM:
+    case TK_BITAND:
+    case TK_BITOR:
+    case TK_SLASH:
+    case TK_LSHIFT:
+    case TK_RSHIFT: 
+    case TK_CONCAT: {
+      assert( TK_AND==OP_And );
+      assert( TK_OR==OP_Or );
+      assert( TK_PLUS==OP_Add );
+      assert( TK_MINUS==OP_Subtract );
+      assert( TK_REM==OP_Remainder );
+      assert( TK_BITAND==OP_BitAnd );
+      assert( TK_BITOR==OP_BitOr );
+      assert( TK_SLASH==OP_Divide );
+      assert( TK_LSHIFT==OP_ShiftLeft );
+      assert( TK_RSHIFT==OP_ShiftRight );
+      assert( TK_CONCAT==OP_Concat );
+      testcase( op==TK_AND );
+      testcase( op==TK_OR );
+      testcase( op==TK_PLUS );
+      testcase( op==TK_MINUS );
+      testcase( op==TK_REM );
+      testcase( op==TK_BITAND );
+      testcase( op==TK_BITOR );
+      testcase( op==TK_SLASH );
+      testcase( op==TK_LSHIFT );
+      testcase( op==TK_RSHIFT );
+      testcase( op==TK_CONCAT );
       r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
       r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
-      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
-                  r1, r2, dest, jumpIfNull);
+      sqlite3VdbeAddOp3(v, op, r2, r1, target);
+      testcase( regFree1==0 );
+      testcase( regFree2==0 );
+      break;
+    }
+    case TK_UMINUS: {
+      Expr *pLeft = pExpr->pLeft;
+      assert( pLeft );
+      if( pLeft->op==TK_FLOAT || pLeft->op==TK_INTEGER ){
+        if( pLeft->op==TK_FLOAT ){
+          codeReal(v, (char*)pLeft->token.z, pLeft->token.n, 1, target);
+        }else{
+          codeInteger(v, pLeft, 1, target);
+        }
+      }else{
+        regFree1 = r1 = sqlite3GetTempReg(pParse);
+        sqlite3VdbeAddOp2(v, OP_Integer, 0, r1);
+        r2 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free2);
+        sqlite3VdbeAddOp3(v, OP_Subtract, r2, r1, target);
+        testcase( regFree2==0 );
+      }
+      inReg = target;
+      break;
+    }
+    case TK_BITNOT:
+    case TK_NOT: {
+      assert( TK_BITNOT==OP_BitNot );
+      assert( TK_NOT==OP_Not );
+      testcase( op==TK_BITNOT );
+      testcase( op==TK_NOT );
+      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
+      testcase( inReg==target );
+      testcase( usedAsColumnCache(pParse, inReg, inReg) );
+      inReg = sqlite3ExprWritableRegister(pParse, inReg, target);
+      sqlite3VdbeAddOp1(v, op, inReg);
       break;
     }
     case TK_ISNULL:
     case TK_NOTNULL: {
+      int addr;
       assert( TK_ISNULL==OP_IsNull );
       assert( TK_NOTNULL==OP_NotNull );
+      testcase( op==TK_ISNULL );
+      testcase( op==TK_NOTNULL );
+      sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
       r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
-      sqlite3VdbeAddOp2(v, op, r1, dest);
+      testcase( regFree1==0 );
+      addr = sqlite3VdbeAddOp1(v, op, r1);
+      sqlite3VdbeAddOp2(v, OP_AddImm, target, -1);
+      sqlite3VdbeJumpHere(v, addr);
       break;
     }
-    case TK_BETWEEN: {
-      /*    x BETWEEN y AND z
-      **
-      ** Is equivalent to 
-      **
-      **    x>=y AND x<=z
-      **
-      ** Code it as such, taking care to do the common subexpression
-      ** elementation of x.
-      */
-      Expr exprAnd;
-      Expr compLeft;
-      Expr compRight;
-      Expr exprX;
-
-      exprX = *pExpr->pLeft;
-      exprAnd.op = TK_AND;
-      exprAnd.pLeft = &compLeft;
+    case TK_AGG_FUNCTION: {
+      AggInfo *pInfo = pExpr->pAggInfo;
+      if( pInfo==0 ){
+        sqlite3ErrorMsg(pParse, "misuse of aggregate: %T",
+            &pExpr->span);
+      }else{
+        inReg = pInfo->aFunc[pExpr->iAgg].iMem;
+      }
+      break;
+    }
+    case TK_CONST_FUNC:
+    case TK_FUNCTION: {
+      ExprList *pList = pExpr->pList;
+      int nExpr = pList ? pList->nExpr : 0;
+      FuncDef *pDef;
+      int nId;
+      const char *zId;
+      int constMask = 0;
+      int i;
+      u8 enc = ENC(db);
+      CollSeq *pColl = 0;
+
+      testcase( op==TK_CONST_FUNC );
+      testcase( op==TK_FUNCTION );
+      zId = (char*)pExpr->token.z;
+      nId = pExpr->token.n;
+      pDef = sqlite3FindFunction(db, zId, nId, nExpr, enc, 0);
+      assert( pDef!=0 );
+      if( pList ){
+        nExpr = pList->nExpr;
+        r1 = sqlite3GetTempRange(pParse, nExpr);
+        sqlite3ExprCodeExprList(pParse, pList, r1, 1);
+      }else{
+        nExpr = r1 = 0;
+      }
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+      /* Possibly overload the function if the first argument is
+      ** a virtual table column.
+      **
+      ** For infix functions (LIKE, GLOB, REGEXP, and MATCH) use the
+      ** second argument, not the first, as the argument to test to
+      ** see if it is a column in a virtual table.  This is done because
+      ** the left operand of infix functions (the operand we want to
+      ** control overloading) ends up as the second argument to the
+      ** function.  The expression "A glob B" is equivalent to 
+      ** "glob(B,A).  We want to use the A in "A glob B" to test
+      ** for function overloading.  But we use the B term in "glob(B,A)".
+      */
+      if( nExpr>=2 && (pExpr->flags & EP_InfixFunc) ){
+        pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[1].pExpr);
+      }else if( nExpr>0 ){
+        pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[0].pExpr);
+      }
+#endif
+      for(i=0; ia[i].pExpr) ){
+          constMask |= (1<flags & SQLITE_FUNC_NEEDCOLL)!=0 && !pColl ){
+          pColl = sqlite3ExprCollSeq(pParse, pList->a[i].pExpr);
+        }
+      }
+      if( pDef->flags & SQLITE_FUNC_NEEDCOLL ){
+        if( !pColl ) pColl = db->pDfltColl; 
+        sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ);
+      }
+      sqlite3VdbeAddOp4(v, OP_Function, constMask, r1, target,
+                        (char*)pDef, P4_FUNCDEF);
+      sqlite3VdbeChangeP5(v, nExpr);
+      if( nExpr ){
+        sqlite3ReleaseTempRange(pParse, r1, nExpr);
+      }
+      sqlite3ExprCacheAffinityChange(pParse, r1, nExpr);
+      break;
+    }
+#ifndef SQLITE_OMIT_SUBQUERY
+    case TK_EXISTS:
+    case TK_SELECT: {
+      testcase( op==TK_EXISTS );
+      testcase( op==TK_SELECT );
+      if( pExpr->iColumn==0 ){
+        sqlite3CodeSubselect(pParse, pExpr, 0, 0);
+      }
+      inReg = pExpr->iColumn;
+      break;
+    }
+    case TK_IN: {
+      int rNotFound = 0;
+      int rMayHaveNull = 0;
+      int j2, j3, j4, j5;
+      char affinity;
+      int eType;
+
+      VdbeNoopComment((v, "begin IN expr r%d", target));
+      eType = sqlite3FindInIndex(pParse, pExpr, &rMayHaveNull);
+      if( rMayHaveNull ){
+        rNotFound = ++pParse->nMem;
+      }
+
+      /* Figure out the affinity to use to create a key from the results
+      ** of the expression. affinityStr stores a static string suitable for
+      ** P4 of OP_MakeRecord.
+      */
+      affinity = comparisonAffinity(pExpr);
+
+
+      /* Code the  from " IN (...)". The temporary table
+      ** pExpr->iTable contains the values that make up the (...) set.
+      */
+      pParse->disableColCache++;
+      sqlite3ExprCode(pParse, pExpr->pLeft, target);
+      pParse->disableColCache--;
+      j2 = sqlite3VdbeAddOp1(v, OP_IsNull, target);
+      if( eType==IN_INDEX_ROWID ){
+        j3 = sqlite3VdbeAddOp1(v, OP_MustBeInt, target);
+        j4 = sqlite3VdbeAddOp3(v, OP_NotExists, pExpr->iTable, 0, target);
+        sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
+        j5 = sqlite3VdbeAddOp0(v, OP_Goto);
+        sqlite3VdbeJumpHere(v, j3);
+        sqlite3VdbeJumpHere(v, j4);
+        sqlite3VdbeAddOp2(v, OP_Integer, 0, target);
+      }else{
+        r2 = regFree2 = sqlite3GetTempReg(pParse);
+
+        /* Create a record and test for set membership. If the set contains
+        ** the value, then jump to the end of the test code. The target
+        ** register still contains the true (1) value written to it earlier.
+        */
+        sqlite3VdbeAddOp4(v, OP_MakeRecord, target, 1, r2, &affinity, 1);
+        sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
+        j5 = sqlite3VdbeAddOp3(v, OP_Found, pExpr->iTable, 0, r2);
+
+        /* If the set membership test fails, then the result of the 
+        ** "x IN (...)" expression must be either 0 or NULL. If the set
+        ** contains no NULL values, then the result is 0. If the set 
+        ** contains one or more NULL values, then the result of the
+        ** expression is also NULL.
+        */
+        if( rNotFound==0 ){
+          /* This branch runs if it is known at compile time (now) that 
+          ** the set contains no NULL values. This happens as the result
+          ** of a "NOT NULL" constraint in the database schema. No need
+          ** to test the data structure at runtime in this case.
+          */
+          sqlite3VdbeAddOp2(v, OP_Integer, 0, target);
+        }else{
+          /* This block populates the rNotFound register with either NULL
+          ** or 0 (an integer value). If the data structure contains one
+          ** or more NULLs, then set rNotFound to NULL. Otherwise, set it
+          ** to 0. If register rMayHaveNull is already set to some value
+          ** other than NULL, then the test has already been run and 
+          ** rNotFound is already populated.
+          */
+          static const char nullRecord[] = { 0x02, 0x00 };
+          j3 = sqlite3VdbeAddOp1(v, OP_NotNull, rMayHaveNull);
+          sqlite3VdbeAddOp2(v, OP_Null, 0, rNotFound);
+          sqlite3VdbeAddOp4(v, OP_Blob, 2, rMayHaveNull, 0, 
+                             nullRecord, P4_STATIC);
+          j4 = sqlite3VdbeAddOp3(v, OP_Found, pExpr->iTable, 0, rMayHaveNull);
+          sqlite3VdbeAddOp2(v, OP_Integer, 0, rNotFound);
+          sqlite3VdbeJumpHere(v, j4);
+          sqlite3VdbeJumpHere(v, j3);
+
+          /* Copy the value of register rNotFound (which is either NULL or 0)
+          ** into the target register. This will be the result of the
+          ** expression.
+          */
+          sqlite3VdbeAddOp2(v, OP_Copy, rNotFound, target);
+        }
+      }
+      sqlite3VdbeJumpHere(v, j2);
+      sqlite3VdbeJumpHere(v, j5);
+      VdbeComment((v, "end IN expr r%d", target));
+      break;
+    }
+#endif
+    /*
+    **    x BETWEEN y AND z
+    **
+    ** This is equivalent to
+    **
+    **    x>=y AND x<=z
+    **
+    ** X is stored in pExpr->pLeft.
+    ** Y is stored in pExpr->pList->a[0].pExpr.
+    ** Z is stored in pExpr->pList->a[1].pExpr.
+    */
+    case TK_BETWEEN: {
+      Expr *pLeft = pExpr->pLeft;
+      struct ExprList_item *pLItem = pExpr->pList->a;
+      Expr *pRight = pLItem->pExpr;
+
+      codeCompareOperands(pParse, pLeft, &r1, ®Free1,
+                                  pRight, &r2, ®Free2);
+      testcase( regFree1==0 );
+      testcase( regFree2==0 );
+      r3 = sqlite3GetTempReg(pParse);
+      r4 = sqlite3GetTempReg(pParse);
+      codeCompare(pParse, pLeft, pRight, OP_Ge,
+                  r1, r2, r3, SQLITE_STOREP2);
+      pLItem++;
+      pRight = pLItem->pExpr;
+      sqlite3ReleaseTempReg(pParse, regFree2);
+      r2 = sqlite3ExprCodeTemp(pParse, pRight, ®Free2);
+      testcase( regFree2==0 );
+      codeCompare(pParse, pLeft, pRight, OP_Le, r1, r2, r4, SQLITE_STOREP2);
+      sqlite3VdbeAddOp3(v, OP_And, r3, r4, target);
+      sqlite3ReleaseTempReg(pParse, r3);
+      sqlite3ReleaseTempReg(pParse, r4);
+      break;
+    }
+    case TK_UPLUS: {
+      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
+      break;
+    }
+
+    /*
+    ** Form A:
+    **   CASE x WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END
+    **
+    ** Form B:
+    **   CASE WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END
+    **
+    ** Form A is can be transformed into the equivalent form B as follows:
+    **   CASE WHEN x=e1 THEN r1 WHEN x=e2 THEN r2 ...
+    **        WHEN x=eN THEN rN ELSE y END
+    **
+    ** X (if it exists) is in pExpr->pLeft.
+    ** Y is in pExpr->pRight.  The Y is also optional.  If there is no
+    ** ELSE clause and no other term matches, then the result of the
+    ** exprssion is NULL.
+    ** Ei is in pExpr->pList->a[i*2] and Ri is pExpr->pList->a[i*2+1].
+    **
+    ** The result of the expression is the Ri for the first matching Ei,
+    ** or if there is no matching Ei, the ELSE term Y, or if there is
+    ** no ELSE term, NULL.
+    */
+    case TK_CASE: {
+      int endLabel;                     /* GOTO label for end of CASE stmt */
+      int nextCase;                     /* GOTO label for next WHEN clause */
+      int nExpr;                        /* 2x number of WHEN terms */
+      int i;                            /* Loop counter */
+      ExprList *pEList;                 /* List of WHEN terms */
+      struct ExprList_item *aListelem;  /* Array of WHEN terms */
+      Expr opCompare;                   /* The X==Ei expression */
+      Expr cacheX;                      /* Cached expression X */
+      Expr *pX;                         /* The X expression */
+      Expr *pTest;                      /* X==Ei (form A) or just Ei (form B) */
+
+      assert(pExpr->pList);
+      assert((pExpr->pList->nExpr % 2) == 0);
+      assert(pExpr->pList->nExpr > 0);
+      pEList = pExpr->pList;
+      aListelem = pEList->a;
+      nExpr = pEList->nExpr;
+      endLabel = sqlite3VdbeMakeLabel(v);
+      if( (pX = pExpr->pLeft)!=0 ){
+        cacheX = *pX;
+        testcase( pX->op==TK_COLUMN || pX->op==TK_REGISTER );
+        cacheX.iTable = sqlite3ExprCodeTemp(pParse, pX, ®Free1);
+        testcase( regFree1==0 );
+        cacheX.op = TK_REGISTER;
+        opCompare.op = TK_EQ;
+        opCompare.pLeft = &cacheX;
+        pTest = &opCompare;
+      }
+      pParse->disableColCache++;
+      for(i=0; iop==TK_COLUMN || pTest->op==TK_REGISTER );
+        sqlite3ExprIfFalse(pParse, pTest, nextCase, SQLITE_JUMPIFNULL);
+        testcase( aListelem[i+1].pExpr->op==TK_COLUMN );
+        testcase( aListelem[i+1].pExpr->op==TK_REGISTER );
+        sqlite3ExprCode(pParse, aListelem[i+1].pExpr, target);
+        sqlite3VdbeAddOp2(v, OP_Goto, 0, endLabel);
+        sqlite3VdbeResolveLabel(v, nextCase);
+      }
+      if( pExpr->pRight ){
+        sqlite3ExprCode(pParse, pExpr->pRight, target);
+      }else{
+        sqlite3VdbeAddOp2(v, OP_Null, 0, target);
+      }
+      sqlite3VdbeResolveLabel(v, endLabel);
+      assert( pParse->disableColCache>0 );
+      pParse->disableColCache--;
+      break;
+    }
+#ifndef SQLITE_OMIT_TRIGGER
+    case TK_RAISE: {
+      if( !pParse->trigStack ){
+        sqlite3ErrorMsg(pParse,
+                       "RAISE() may only be used within a trigger-program");
+        return 0;
+      }
+      if( pExpr->iColumn!=OE_Ignore ){
+         assert( pExpr->iColumn==OE_Rollback ||
+                 pExpr->iColumn == OE_Abort ||
+                 pExpr->iColumn == OE_Fail );
+         sqlite3DequoteExpr(db, pExpr);
+         sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, pExpr->iColumn, 0,
+                        (char*)pExpr->token.z, pExpr->token.n);
+      } else {
+         assert( pExpr->iColumn == OE_Ignore );
+         sqlite3VdbeAddOp2(v, OP_ContextPop, 0, 0);
+         sqlite3VdbeAddOp2(v, OP_Goto, 0, pParse->trigStack->ignoreJump);
+         VdbeComment((v, "raise(IGNORE)"));
+      }
+      break;
+    }
+#endif
+  }
+  sqlite3ReleaseTempReg(pParse, regFree1);
+  sqlite3ReleaseTempReg(pParse, regFree2);
+  return inReg;
+}
+
+/*
+** Generate code to evaluate an expression and store the results
+** into a register.  Return the register number where the results
+** are stored.
+**
+** If the register is a temporary register that can be deallocated,
+** then write its number into *pReg.  If the result register is not
+** a temporary, then set *pReg to zero.
+*/
+SQLITE_PRIVATE int sqlite3ExprCodeTemp(Parse *pParse, Expr *pExpr, int *pReg){
+  int r1 = sqlite3GetTempReg(pParse);
+  int r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
+  if( r2==r1 ){
+    *pReg = r1;
+  }else{
+    sqlite3ReleaseTempReg(pParse, r1);
+    *pReg = 0;
+  }
+  return r2;
+}
+
+/*
+** Generate code that will evaluate expression pExpr and store the
+** results in register target.  The results are guaranteed to appear
+** in register target.
+*/
+SQLITE_PRIVATE int sqlite3ExprCode(Parse *pParse, Expr *pExpr, int target){
+  int inReg;
+
+  assert( target>0 && target<=pParse->nMem );
+  inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
+  assert( pParse->pVdbe || pParse->db->mallocFailed );
+  if( inReg!=target && pParse->pVdbe ){
+    sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, inReg, target);
+  }
+  return target;
+}
+
+/*
+** Generate code that evalutes the given expression and puts the result
+** in register target.
+**
+** Also make a copy of the expression results into another "cache" register
+** and modify the expression so that the next time it is evaluated,
+** the result is a copy of the cache register.
+**
+** This routine is used for expressions that are used multiple 
+** times.  They are evaluated once and the results of the expression
+** are reused.
+*/
+SQLITE_PRIVATE int sqlite3ExprCodeAndCache(Parse *pParse, Expr *pExpr, int target){
+  Vdbe *v = pParse->pVdbe;
+  int inReg;
+  inReg = sqlite3ExprCode(pParse, pExpr, target);
+  assert( target>0 );
+  if( pExpr->op!=TK_REGISTER ){  
+    int iMem;
+    iMem = ++pParse->nMem;
+    sqlite3VdbeAddOp2(v, OP_Copy, inReg, iMem);
+    pExpr->iTable = iMem;
+    pExpr->op = TK_REGISTER;
+  }
+  return inReg;
+}
+
+/*
+** Return TRUE if pExpr is an constant expression that is appropriate
+** for factoring out of a loop.  Appropriate expressions are:
+**
+**    *  Any expression that evaluates to two or more opcodes.
+**
+**    *  Any OP_Integer, OP_Real, OP_String, OP_Blob, OP_Null, 
+**       or OP_Variable that does not need to be placed in a 
+**       specific register.
+**
+** There is no point in factoring out single-instruction constant
+** expressions that need to be placed in a particular register.  
+** We could factor them out, but then we would end up adding an
+** OP_SCopy instruction to move the value into the correct register
+** later.  We might as well just use the original instruction and
+** avoid the OP_SCopy.
+*/
+static int isAppropriateForFactoring(Expr *p){
+  if( !sqlite3ExprIsConstantNotJoin(p) ){
+    return 0;  /* Only constant expressions are appropriate for factoring */
+  }
+  if( (p->flags & EP_FixedDest)==0 ){
+    return 1;  /* Any constant without a fixed destination is appropriate */
+  }
+  while( p->op==TK_UPLUS ) p = p->pLeft;
+  switch( p->op ){
+#ifndef SQLITE_OMIT_BLOB_LITERAL
+    case TK_BLOB:
+#endif
+    case TK_VARIABLE:
+    case TK_INTEGER:
+    case TK_FLOAT:
+    case TK_NULL:
+    case TK_STRING: {
+      testcase( p->op==TK_BLOB );
+      testcase( p->op==TK_VARIABLE );
+      testcase( p->op==TK_INTEGER );
+      testcase( p->op==TK_FLOAT );
+      testcase( p->op==TK_NULL );
+      testcase( p->op==TK_STRING );
+      /* Single-instruction constants with a fixed destination are
+      ** better done in-line.  If we factor them, they will just end
+      ** up generating an OP_SCopy to move the value to the destination
+      ** register. */
+      return 0;
+    }
+    case TK_UMINUS: {
+       if( p->pLeft->op==TK_FLOAT || p->pLeft->op==TK_INTEGER ){
+         return 0;
+       }
+       break;
+    }
+    default: {
+      break;
+    }
+  }
+  return 1;
+}
+
+/*
+** If pExpr is a constant expression that is appropriate for
+** factoring out of a loop, then evaluate the expression
+** into a register and convert the expression into a TK_REGISTER
+** expression.
+*/
+static int evalConstExpr(Walker *pWalker, Expr *pExpr){
+  Parse *pParse = pWalker->pParse;
+  switch( pExpr->op ){
+    case TK_REGISTER: {
+      return 1;
+    }
+    case TK_FUNCTION:
+    case TK_AGG_FUNCTION:
+    case TK_CONST_FUNC: {
+      /* The arguments to a function have a fixed destination.
+      ** Mark them this way to avoid generated unneeded OP_SCopy
+      ** instructions. 
+      */
+      ExprList *pList = pExpr->pList;
+      if( pList ){
+        int i = pList->nExpr;
+        struct ExprList_item *pItem = pList->a;
+        for(; i>0; i--, pItem++){
+          if( pItem->pExpr ) pItem->pExpr->flags |= EP_FixedDest;
+        }
+      }
+      break;
+    }
+  }
+  if( isAppropriateForFactoring(pExpr) ){
+    int r1 = ++pParse->nMem;
+    int r2;
+    r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
+    if( r1!=r2 ) sqlite3ReleaseTempReg(pParse, r1);
+    pExpr->op = TK_REGISTER;
+    pExpr->iTable = r2;
+    return WRC_Prune;
+  }
+  return WRC_Continue;
+}
+
+/*
+** Preevaluate constant subexpressions within pExpr and store the
+** results in registers.  Modify pExpr so that the constant subexpresions
+** are TK_REGISTER opcodes that refer to the precomputed values.
+*/
+SQLITE_PRIVATE void sqlite3ExprCodeConstants(Parse *pParse, Expr *pExpr){
+  Walker w;
+  w.xExprCallback = evalConstExpr;
+  w.xSelectCallback = 0;
+  w.pParse = pParse;
+  sqlite3WalkExpr(&w, pExpr);
+}
+
+
+/*
+** Generate code that pushes the value of every element of the given
+** expression list into a sequence of registers beginning at target.
+**
+** Return the number of elements evaluated.
+*/
+SQLITE_PRIVATE int sqlite3ExprCodeExprList(
+  Parse *pParse,     /* Parsing context */
+  ExprList *pList,   /* The expression list to be coded */
+  int target,        /* Where to write results */
+  int doHardCopy     /* Make a hard copy of every element */
+){
+  struct ExprList_item *pItem;
+  int i, n;
+  assert( pList!=0 );
+  assert( target>0 );
+  n = pList->nExpr;
+  for(pItem=pList->a, i=0; iiAlias ){
+      int iReg = codeAlias(pParse, pItem->iAlias, pItem->pExpr);
+      Vdbe *v = sqlite3GetVdbe(pParse);
+      sqlite3VdbeAddOp2(v, OP_SCopy, iReg, target+i);
+    }else{
+      sqlite3ExprCode(pParse, pItem->pExpr, target+i);
+    }
+    if( doHardCopy ){
+      sqlite3ExprHardCopy(pParse, target, n);
+    }
+  }
+  return n;
+}
+
+/*
+** Generate code for a boolean expression such that a jump is made
+** to the label "dest" if the expression is true but execution
+** continues straight thru if the expression is false.
+**
+** If the expression evaluates to NULL (neither true nor false), then
+** take the jump if the jumpIfNull flag is SQLITE_JUMPIFNULL.
+**
+** This code depends on the fact that certain token values (ex: TK_EQ)
+** are the same as opcode values (ex: OP_Eq) that implement the corresponding
+** operation.  Special comments in vdbe.c and the mkopcodeh.awk script in
+** the make process cause these values to align.  Assert()s in the code
+** below verify that the numbers are aligned correctly.
+*/
+SQLITE_PRIVATE void sqlite3ExprIfTrue(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
+  Vdbe *v = pParse->pVdbe;
+  int op = 0;
+  int regFree1 = 0;
+  int regFree2 = 0;
+  int r1, r2;
+
+  assert( jumpIfNull==SQLITE_JUMPIFNULL || jumpIfNull==0 );
+  if( v==0 || pExpr==0 ) return;
+  op = pExpr->op;
+  switch( op ){
+    case TK_AND: {
+      int d2 = sqlite3VdbeMakeLabel(v);
+      testcase( jumpIfNull==0 );
+      testcase( pParse->disableColCache==0 );
+      sqlite3ExprIfFalse(pParse, pExpr->pLeft, d2,jumpIfNull^SQLITE_JUMPIFNULL);
+      pParse->disableColCache++;
+      sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
+      assert( pParse->disableColCache>0 );
+      pParse->disableColCache--;
+      sqlite3VdbeResolveLabel(v, d2);
+      break;
+    }
+    case TK_OR: {
+      testcase( jumpIfNull==0 );
+      testcase( pParse->disableColCache==0 );
+      sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
+      pParse->disableColCache++;
+      sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
+      assert( pParse->disableColCache>0 );
+      pParse->disableColCache--;
+      break;
+    }
+    case TK_NOT: {
+      testcase( jumpIfNull==0 );
+      sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
+      break;
+    }
+    case TK_LT:
+    case TK_LE:
+    case TK_GT:
+    case TK_GE:
+    case TK_NE:
+    case TK_EQ: {
+      assert( TK_LT==OP_Lt );
+      assert( TK_LE==OP_Le );
+      assert( TK_GT==OP_Gt );
+      assert( TK_GE==OP_Ge );
+      assert( TK_EQ==OP_Eq );
+      assert( TK_NE==OP_Ne );
+      testcase( op==TK_LT );
+      testcase( op==TK_LE );
+      testcase( op==TK_GT );
+      testcase( op==TK_GE );
+      testcase( op==TK_EQ );
+      testcase( op==TK_NE );
+      testcase( jumpIfNull==0 );
+      codeCompareOperands(pParse, pExpr->pLeft, &r1, ®Free1,
+                                  pExpr->pRight, &r2, ®Free2);
+      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
+                  r1, r2, dest, jumpIfNull);
+      testcase( regFree1==0 );
+      testcase( regFree2==0 );
+      break;
+    }
+    case TK_ISNULL:
+    case TK_NOTNULL: {
+      assert( TK_ISNULL==OP_IsNull );
+      assert( TK_NOTNULL==OP_NotNull );
+      testcase( op==TK_ISNULL );
+      testcase( op==TK_NOTNULL );
+      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
+      sqlite3VdbeAddOp2(v, op, r1, dest);
+      testcase( regFree1==0 );
+      break;
+    }
+    case TK_BETWEEN: {
+      /*    x BETWEEN y AND z
+      **
+      ** Is equivalent to 
+      **
+      **    x>=y AND x<=z
+      **
+      ** Code it as such, taking care to do the common subexpression
+      ** elementation of x.
+      */
+      Expr exprAnd;
+      Expr compLeft;
+      Expr compRight;
+      Expr exprX;
+
+      exprX = *pExpr->pLeft;
+      exprAnd.op = TK_AND;
+      exprAnd.pLeft = &compLeft;
       exprAnd.pRight = &compRight;
       compLeft.op = TK_GE;
       compLeft.pLeft = &exprX;
@@ -48494,13 +55574,17 @@ SQLITE_PRIVATE void sqlite3ExprIfTrue(Parse *pParse, Expr *pExpr, int dest, int
       compRight.pLeft = &exprX;
       compRight.pRight = pExpr->pList->a[1].pExpr;
       exprX.iTable = sqlite3ExprCodeTemp(pParse, &exprX, ®Free1);
+      testcase( regFree1==0 );
       exprX.op = TK_REGISTER;
+      testcase( jumpIfNull==0 );
       sqlite3ExprIfTrue(pParse, &exprAnd, dest, jumpIfNull);
       break;
     }
     default: {
       r1 = sqlite3ExprCodeTemp(pParse, pExpr, ®Free1);
       sqlite3VdbeAddOp3(v, OP_If, r1, dest, jumpIfNull!=0);
+      testcase( regFree1==0 );
+      testcase( jumpIfNull==0 );
       break;
     }
   }
@@ -48560,14 +55644,24 @@ SQLITE_PRIVATE void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int
 
   switch( pExpr->op ){
     case TK_AND: {
+      testcase( jumpIfNull==0 );
+      testcase( pParse->disableColCache==0 );
       sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
+      pParse->disableColCache++;
       sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
+      assert( pParse->disableColCache>0 );
+      pParse->disableColCache--;
       break;
     }
     case TK_OR: {
       int d2 = sqlite3VdbeMakeLabel(v);
+      testcase( jumpIfNull==0 );
+      testcase( pParse->disableColCache==0 );
       sqlite3ExprIfTrue(pParse, pExpr->pLeft, d2, jumpIfNull^SQLITE_JUMPIFNULL);
+      pParse->disableColCache++;
       sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
+      assert( pParse->disableColCache>0 );
+      pParse->disableColCache--;
       sqlite3VdbeResolveLabel(v, d2);
       break;
     }
@@ -48581,16 +55675,28 @@ SQLITE_PRIVATE void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int
     case TK_GE:
     case TK_NE:
     case TK_EQ: {
-      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
-      r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
+      testcase( op==TK_LT );
+      testcase( op==TK_LE );
+      testcase( op==TK_GT );
+      testcase( op==TK_GE );
+      testcase( op==TK_EQ );
+      testcase( op==TK_NE );
+      testcase( jumpIfNull==0 );
+      codeCompareOperands(pParse, pExpr->pLeft, &r1, ®Free1,
+                                  pExpr->pRight, &r2, ®Free2);
       codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
                   r1, r2, dest, jumpIfNull);
+      testcase( regFree1==0 );
+      testcase( regFree2==0 );
       break;
     }
     case TK_ISNULL:
     case TK_NOTNULL: {
+      testcase( op==TK_ISNULL );
+      testcase( op==TK_NOTNULL );
       r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
       sqlite3VdbeAddOp2(v, op, r1, dest);
+      testcase( regFree1==0 );
       break;
     }
     case TK_BETWEEN: {
@@ -48619,13 +55725,17 @@ SQLITE_PRIVATE void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int
       compRight.pLeft = &exprX;
       compRight.pRight = pExpr->pList->a[1].pExpr;
       exprX.iTable = sqlite3ExprCodeTemp(pParse, &exprX, ®Free1);
+      testcase( regFree1==0 );
       exprX.op = TK_REGISTER;
+      testcase( jumpIfNull==0 );
       sqlite3ExprIfFalse(pParse, &exprAnd, dest, jumpIfNull);
       break;
     }
     default: {
       r1 = sqlite3ExprCodeTemp(pParse, pExpr, ®Free1);
       sqlite3VdbeAddOp3(v, OP_IfNot, r1, dest, jumpIfNull!=0);
+      testcase( regFree1==0 );
+      testcase( jumpIfNull==0 );
       break;
     }
   }
@@ -48717,15 +55827,13 @@ static int addAggInfoFunc(sqlite3 *db, AggInfo *pInfo){
 }    
 
 /*
-** This is an xFunc for walkExprTree() used to implement 
-** sqlite3ExprAnalyzeAggregates().  See sqlite3ExprAnalyzeAggregates
+** This is the xExprCallback for a tree walker.  It is used to
+** implement sqlite3ExprAnalyzeAggregates().  See sqlite3ExprAnalyzeAggregates
 ** for additional information.
-**
-** This routine analyzes the aggregate function at pExpr.
 */
-static int analyzeAggregate(void *pArg, Expr *pExpr){
+static int analyzeAggregate(Walker *pWalker, Expr *pExpr){
   int i;
-  NameContext *pNC = (NameContext *)pArg;
+  NameContext *pNC = pWalker->u.pNC;
   Parse *pParse = pNC->pParse;
   SrcList *pSrcList = pNC->pSrcList;
   AggInfo *pAggInfo = pNC->pAggInfo;
@@ -48733,6 +55841,8 @@ static int analyzeAggregate(void *pArg, Expr *pExpr){
   switch( pExpr->op ){
     case TK_AGG_COLUMN:
     case TK_COLUMN: {
+      testcase( pExpr->op==TK_AGG_COLUMN );
+      testcase( pExpr->op==TK_COLUMN );
       /* Check to see if the column is in one of the tables in the FROM
       ** clause of the aggregate query */
       if( pSrcList ){
@@ -48794,7 +55904,7 @@ static int analyzeAggregate(void *pArg, Expr *pExpr){
           } /* endif pExpr->iTable==pItem->iCursor */
         } /* end loop over pSrcList */
       }
-      return 1;
+      return WRC_Prune;
     }
     case TK_AGG_FUNCTION: {
       /* The pNC->nDepth==0 test causes aggregate functions in subqueries
@@ -48832,21 +55942,22 @@ static int analyzeAggregate(void *pArg, Expr *pExpr){
         */
         pExpr->iAgg = i;
         pExpr->pAggInfo = pAggInfo;
-        return 1;
+        return WRC_Prune;
       }
     }
   }
-
-  /* Recursively walk subqueries looking for TK_COLUMN nodes that need
-  ** to be changed to TK_AGG_COLUMN.  But increment nDepth so that
-  ** TK_AGG_FUNCTION nodes in subqueries will be unchanged.
-  */
-  if( pExpr->pSelect ){
+  return WRC_Continue;
+}
+static int analyzeAggregatesInSelect(Walker *pWalker, Select *pSelect){
+  NameContext *pNC = pWalker->u.pNC;
+  if( pNC->nDepth==0 ){
     pNC->nDepth++;
-    walkSelectExpr(pExpr->pSelect, analyzeAggregate, pNC);
+    sqlite3WalkSelect(pWalker, pSelect);
     pNC->nDepth--;
+    return WRC_Prune;
+  }else{
+    return WRC_Continue;
   }
-  return 0;
 }
 
 /*
@@ -48855,10 +55966,14 @@ static int analyzeAggregate(void *pArg, Expr *pExpr){
 ** Make additional entries to the pParse->aAgg[] array as necessary.
 **
 ** This routine should only be called after the expression has been
-** analyzed by sqlite3ExprResolveNames().
+** analyzed by sqlite3ResolveExprNames().
 */
 SQLITE_PRIVATE void sqlite3ExprAnalyzeAggregates(NameContext *pNC, Expr *pExpr){
-  walkExprTree(pExpr, analyzeAggregate, pNC);
+  Walker w;
+  w.xExprCallback = analyzeAggregate;
+  w.xSelectCallback = analyzeAggregatesInSelect;
+  w.u.pNC = pNC;
+  sqlite3WalkExpr(&w, pExpr);
 }
 
 /*
@@ -48881,15 +55996,14 @@ SQLITE_PRIVATE void sqlite3ExprAnalyzeAggList(NameContext *pNC, ExprList *pList)
 ** Allocate or deallocate temporary use registers during code generation.
 */
 SQLITE_PRIVATE int sqlite3GetTempReg(Parse *pParse){
-  if( pParse->nTempReg ){
-    return pParse->aTempReg[--pParse->nTempReg];
-  }else{
+  if( pParse->nTempReg==0 ){
     return ++pParse->nMem;
   }
+  return pParse->aTempReg[--pParse->nTempReg];
 }
 SQLITE_PRIVATE void sqlite3ReleaseTempReg(Parse *pParse, int iReg){
   if( iReg && pParse->nTempRegaTempReg) ){
-    assert( iReg>0 );
+    sqlite3ExprWritableRegister(pParse, iReg, iReg);
     pParse->aTempReg[pParse->nTempReg++] = iReg;
   }
 }
@@ -48898,9 +56012,10 @@ SQLITE_PRIVATE void sqlite3ReleaseTempReg(Parse *pParse, int iReg){
 ** Allocate or deallocate a block of nReg consecutive registers
 */
 SQLITE_PRIVATE int sqlite3GetTempRange(Parse *pParse, int nReg){
-  int i;
-  if( nReg<=pParse->nRangeReg ){
-    i  = pParse->iRangeReg;
+  int i, n;
+  i = pParse->iRangeReg;
+  n = pParse->nRangeReg;
+  if( nReg<=n && !usedAsColumnCache(pParse, i, i+n-1) ){
     pParse->iRangeReg += nReg;
     pParse->nRangeReg -= nReg;
   }else{
@@ -48932,7 +56047,7 @@ SQLITE_PRIVATE void sqlite3ReleaseTempRange(Parse *pParse, int iReg, int nReg){
 ** This file contains C code routines that used to generate VDBE code
 ** that implements the ALTER TABLE command.
 **
-** $Id: alter.c,v 1.42 2008/02/09 14:30:30 drh Exp $
+** $Id: alter.c,v 1.48 2008/08/08 14:19:41 drh Exp $
 */
 
 /*
@@ -48969,11 +56084,11 @@ static void renameTableFunc(
   int len = 0;
   char *zRet;
 
-  sqlite3 *db = sqlite3_user_data(context);
+  sqlite3 *db = sqlite3_context_db_handle(context);
 
   /* The principle used to locate the table name in the CREATE TABLE 
-  ** statement is that the table name is the first token that is immediatedly
-  ** followed by a left parenthesis - TK_LP - or "USING" TK_USING.
+  ** statement is that the table name is the first non-space token that
+  ** is immediately followed by a TK_LP or TK_USING token.
   */
   if( zSql ){
     do {
@@ -48998,7 +56113,7 @@ static void renameTableFunc(
 
     zRet = sqlite3MPrintf(db, "%.*s\"%w\"%s", tname.z - zSql, zSql, 
        zTableName, tname.z+tname.n);
-    sqlite3_result_text(context, zRet, -1, sqlite3_free);
+    sqlite3_result_text(context, zRet, -1, SQLITE_DYNAMIC);
   }
 }
 
@@ -49025,7 +56140,7 @@ static void renameTriggerFunc(
   int len = 0;
   char *zRet;
 
-  sqlite3 *db = sqlite3_user_data(context);
+  sqlite3 *db = sqlite3_context_db_handle(context);
 
   /* The principle used to locate the table name in the CREATE TRIGGER 
   ** statement is that the table name is the first token that is immediatedly
@@ -49073,7 +56188,7 @@ static void renameTriggerFunc(
     */
     zRet = sqlite3MPrintf(db, "%.*s\"%w\"%s", tname.z - zSql, zSql, 
        zTableName, tname.z+tname.n);
-    sqlite3_result_text(context, zRet, -1, sqlite3_free);
+    sqlite3_result_text(context, zRet, -1, SQLITE_DYNAMIC);
   }
 }
 #endif   /* !SQLITE_OMIT_TRIGGER */
@@ -49082,22 +56197,12 @@ static void renameTriggerFunc(
 ** Register built-in functions used to help implement ALTER TABLE
 */
 SQLITE_PRIVATE void sqlite3AlterFunctions(sqlite3 *db){
-  static const struct {
-     char *zName;
-     signed char nArg;
-     void (*xFunc)(sqlite3_context*,int,sqlite3_value **);
-  } aFuncs[] = {
-    { "sqlite_rename_table",    2, renameTableFunc},
+  sqlite3CreateFunc(db, "sqlite_rename_table", 2, SQLITE_UTF8, 0,
+                         renameTableFunc, 0, 0);
 #ifndef SQLITE_OMIT_TRIGGER
-    { "sqlite_rename_trigger",  2, renameTriggerFunc},
+  sqlite3CreateFunc(db, "sqlite_rename_trigger", 2, SQLITE_UTF8, 0,
+                         renameTriggerFunc, 0, 0);
 #endif
-  };
-  int i;
-
-  for(i=0; iname);
-          sqlite3_free(tmp);
+          sqlite3DbFree(db, tmp);
         }
       }
     }
@@ -49337,7 +56442,7 @@ SQLITE_PRIVATE void sqlite3AlterRenameTable(
             "sql = sqlite_rename_trigger(sql, %Q), "
             "tbl_name = %Q "
             "WHERE %s;", zName, zName, zWhere);
-    sqlite3_free(zWhere);
+    sqlite3DbFree(db, zWhere);
   }
 #endif
 
@@ -49345,8 +56450,8 @@ SQLITE_PRIVATE void sqlite3AlterRenameTable(
   reloadTableSchema(pParse, pTab, zName);
 
 exit_rename_table:
-  sqlite3SrcListDelete(pSrc);
-  sqlite3_free(zName);
+  sqlite3SrcListDelete(db, pSrc);
+  sqlite3DbFree(db, zName);
 }
 
 
@@ -49446,7 +56551,7 @@ SQLITE_PRIVATE void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){
       zDb, SCHEMA_TABLE(iDb), pNew->addColOffset, zCol, pNew->addColOffset+1,
       zTab
     );
-    sqlite3_free(zCol);
+    sqlite3DbFree(db, zCol);
   }
 
   /* If the default value of the new column is NULL, then set the file
@@ -49513,6 +56618,7 @@ SQLITE_PRIVATE void sqlite3AlterBeginAddColumn(Parse *pParse, SrcList *pSrc){
   if( !pNew ) goto exit_begin_add_column;
   pParse->pNewTable = pNew;
   pNew->nRef = 1;
+  pNew->db = db;
   pNew->nCol = pTab->nCol;
   assert( pNew->nCol>0 );
   nAlloc = (((pNew->nCol-1)/8)*8)+8;
@@ -49542,7 +56648,7 @@ SQLITE_PRIVATE void sqlite3AlterBeginAddColumn(Parse *pParse, SrcList *pSrc){
   sqlite3ChangeCookie(pParse, iDb);
 
 exit_begin_add_column:
-  sqlite3SrcListDelete(pSrc);
+  sqlite3SrcListDelete(db, pSrc);
   return;
 }
 #endif  /* SQLITE_ALTER_TABLE */
@@ -49562,7 +56668,7 @@ exit_begin_add_column:
 *************************************************************************
 ** This file contains code associated with the ANALYZE command.
 **
-** @(#) $Id: analyze.c,v 1.41 2008/01/25 15:04:49 drh Exp $
+** @(#) $Id: analyze.c,v 1.43 2008/07/28 19:34:53 drh Exp $
 */
 #ifndef SQLITE_OMIT_ANALYZE
 
@@ -49624,9 +56730,9 @@ static void openStatTable(
   if( !createStat1 ){
     sqlite3TableLock(pParse, iDb, iRootPage, 1, "sqlite_stat1");
   }
+  sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, 3);
   sqlite3VdbeAddOp3(v, OP_OpenWrite, iStatCur, iRootPage, iDb);
   sqlite3VdbeChangeP5(v, createStat1);
-  sqlite3VdbeAddOp2(v, OP_SetNumColumns, iStatCur, 3);
 }
 
 /*
@@ -49680,17 +56786,17 @@ static void analyzeOneTable(
     /* Open a cursor to the index to be analyzed
     */
     assert( iDb==sqlite3SchemaToIndex(pParse->db, pIdx->pSchema) );
+    nCol = pIdx->nColumn;
+    sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, nCol+1);
     sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIdx->tnum, iDb,
         (char *)pKey, P4_KEYINFO_HANDOFF);
     VdbeComment((v, "%s", pIdx->zName));
-    nCol = pIdx->nColumn;
     regFields = iMem+nCol*2;
     regTemp = regRowid = regCol = regFields+3;
     regRec = regCol+1;
     if( regRec>pParse->nMem ){
       pParse->nMem = regRec;
     }
-    sqlite3VdbeAddOp2(v, OP_SetNumColumns, iIdxCur, nCol+1);
 
     /* Memory cells are used as follows:
     **
@@ -49866,7 +56972,7 @@ SQLITE_PRIVATE void sqlite3Analyze(Parse *pParse, Token *pName1, Token *pName2){
       z = sqlite3NameFromToken(db, pName1);
       if( z ){
         pTab = sqlite3LocateTable(pParse, 0, z, 0);
-        sqlite3_free(z);
+        sqlite3DbFree(db, z);
         if( pTab ){
           analyzeTable(pParse, pTab);
         }
@@ -49880,7 +56986,7 @@ SQLITE_PRIVATE void sqlite3Analyze(Parse *pParse, Token *pName1, Token *pName2){
       z = sqlite3NameFromToken(db, pTableName);
       if( z ){
         pTab = sqlite3LocateTable(pParse, 0, z, zDb);
-        sqlite3_free(z);
+        sqlite3DbFree(db, z);
         if( pTab ){
           analyzeTable(pParse, pTab);
         }
@@ -49967,7 +57073,7 @@ SQLITE_PRIVATE int sqlite3AnalysisLoad(sqlite3 *db, int iDb){
   (void)sqlite3SafetyOff(db);
   rc = sqlite3_exec(db, zSql, analysisLoader, &sInfo, 0);
   (void)sqlite3SafetyOn(db);
-  sqlite3_free(zSql);
+  sqlite3DbFree(db, zSql);
   return rc;
 }
 
@@ -49989,7 +57095,7 @@ SQLITE_PRIVATE int sqlite3AnalysisLoad(sqlite3 *db, int iDb){
 *************************************************************************
 ** This file contains code used to implement the ATTACH and DETACH commands.
 **
-** $Id: attach.c,v 1.72 2008/02/13 18:25:27 danielk1977 Exp $
+** $Id: attach.c,v 1.78 2008/08/20 16:35:10 drh Exp $
 */
 
 #ifndef SQLITE_OMIT_ATTACH
@@ -50016,7 +57122,7 @@ static int resolveAttachExpr(NameContext *pName, Expr *pExpr)
   int rc = SQLITE_OK;
   if( pExpr ){
     if( pExpr->op!=TK_ID ){
-      rc = sqlite3ExprResolveNames(pName, pExpr);
+      rc = sqlite3ResolveExprNames(pName, pExpr);
       if( rc==SQLITE_OK && !sqlite3ExprIsConstant(pExpr) ){
         sqlite3ErrorMsg(pName->pParse, "invalid name: \"%T\"", &pExpr->span);
         return SQLITE_ERROR;
@@ -50046,7 +57152,7 @@ static void attachFunc(
 ){
   int i;
   int rc = 0;
-  sqlite3 *db = sqlite3_user_data(context);
+  sqlite3 *db = sqlite3_context_db_handle(context);
   const char *zName;
   const char *zFile;
   Db *aNew;
@@ -50064,10 +57170,10 @@ static void attachFunc(
   **     * Transaction currently open
   **     * Specified database name already being used.
   */
-  if( db->nDb>=SQLITE_MAX_ATTACHED+2 ){
+  if( db->nDb>=db->aLimit[SQLITE_LIMIT_ATTACHED]+2 ){
     sqlite3_snprintf(
       sizeof(zErr), zErr, "too many attached databases - max %d", 
-      SQLITE_MAX_ATTACHED
+      db->aLimit[SQLITE_LIMIT_ATTACHED]
     );
     goto attach_error;
   }
@@ -50089,18 +57195,12 @@ static void attachFunc(
   ** hash tables.
   */
   if( db->aDb==db->aDbStatic ){
-    aNew = sqlite3_malloc( sizeof(db->aDb[0])*3 );
-    if( aNew==0 ){
-      db->mallocFailed = 1;
-      return;
-    }
+    aNew = sqlite3DbMallocRaw(db, sizeof(db->aDb[0])*3 );
+    if( aNew==0 ) return;
     memcpy(aNew, db->aDb, sizeof(db->aDb[0])*2);
   }else{
-    aNew = sqlite3_realloc(db->aDb, sizeof(db->aDb[0])*(db->nDb+1) );
-    if( aNew==0 ){
-      db->mallocFailed = 1;
-      return;
-    } 
+    aNew = sqlite3DbRealloc(db, db->aDb, sizeof(db->aDb[0])*(db->nDb+1) );
+    if( aNew==0 ) return;
   }
   db->aDb = aNew;
   aNew = &db->aDb[db->nDb++];
@@ -50114,6 +57214,7 @@ static void attachFunc(
                            db->openFlags | SQLITE_OPEN_MAIN_DB,
                            &aNew->pBt);
   if( rc==SQLITE_OK ){
+    Pager *pPager;
     aNew->pSchema = sqlite3SchemaGet(db, aNew->pBt);
     if( !aNew->pSchema ){
       rc = SQLITE_NOMEM;
@@ -50122,7 +57223,9 @@ static void attachFunc(
         "attached databases must use the same text encoding as main database");
       goto attach_error;
     }
-    sqlite3PagerLockingMode(sqlite3BtreePager(aNew->pBt), db->dfltLockMode);
+    pPager = sqlite3BtreePager(aNew->pBt);
+    sqlite3PagerLockingMode(pPager, db->dfltLockMode);
+    sqlite3PagerJournalMode(pPager, db->dfltJournalMode);
   }
   aNew->zName = sqlite3DbStrDup(db, zName);
   aNew->safety_level = 3;
@@ -50194,7 +57297,7 @@ attach_error:
   /* Return an error if we get here */
   if( zErrDyn ){
     sqlite3_result_error(context, zErrDyn, -1);
-    sqlite3_free(zErrDyn);
+    sqlite3DbFree(db, zErrDyn);
   }else{
     zErr[sizeof(zErr)-1] = 0;
     sqlite3_result_error(context, zErr, -1);
@@ -50216,7 +57319,7 @@ static void detachFunc(
   sqlite3_value **argv
 ){
   const char *zName = (const char *)sqlite3_value_text(argv[0]);
-  sqlite3 *db = sqlite3_user_data(context);
+  sqlite3 *db = sqlite3_context_db_handle(context);
   int i;
   Db *pDb = 0;
   char zErr[128];
@@ -50285,7 +57388,7 @@ static void codeAttach(
       goto attach_end;
     }
     rc = sqlite3AuthCheck(pParse, type, zAuthArg, 0, 0);
-    sqlite3_free(zAuthArg);
+    sqlite3DbFree(db, zAuthArg);
     if(rc!=SQLITE_OK ){
       goto attach_end;
     }
@@ -50325,9 +57428,9 @@ static void codeAttach(
   }
   
 attach_end:
-  sqlite3ExprDelete(pFilename);
-  sqlite3ExprDelete(pDbname);
-  sqlite3ExprDelete(pKey);
+  sqlite3ExprDelete(db, pFilename);
+  sqlite3ExprDelete(db, pDbname);
+  sqlite3ExprDelete(db, pKey);
 }
 
 /*
@@ -50355,8 +57458,8 @@ SQLITE_PRIVATE void sqlite3Attach(Parse *pParse, Expr *p, Expr *pDbname, Expr *p
 SQLITE_PRIVATE void sqlite3AttachFunctions(sqlite3 *db){
 #ifndef SQLITE_OMIT_ATTACH
   static const int enc = SQLITE_UTF8;
-  sqlite3CreateFunc(db, "sqlite_attach", 3, enc, db, attachFunc, 0, 0);
-  sqlite3CreateFunc(db, "sqlite_detach", 1, enc, db, detachFunc, 0, 0);
+  sqlite3CreateFunc(db, "sqlite_attach", 3, enc, 0, attachFunc, 0, 0);
+  sqlite3CreateFunc(db, "sqlite_detach", 1, enc, 0, detachFunc, 0, 0);
 #endif
 }
 
@@ -50765,7 +57868,7 @@ SQLITE_PRIVATE void sqlite3AuthContextPop(AuthContext *pContext){
 **     COMMIT
 **     ROLLBACK
 **
-** $Id: build.c,v 1.474 2008/03/06 09:58:50 mlcreech Exp $
+** $Id: build.c,v 1.498 2008/10/06 16:18:40 danielk1977 Exp $
 */
 
 /*
@@ -50852,10 +57955,8 @@ static void codeTableLocks(Parse *pParse){
   for(i=0; inTableLock; i++){
     TableLock *p = &pParse->aTableLock[i];
     int p1 = p->iDb;
-    if( p->isWriteLock ){
-      p1 = -1*(p1+1);
-    }
-    sqlite3VdbeAddOp4(pVdbe, OP_TableLock, p1, p->iTab, 0, p->zName, P4_STATIC);
+    sqlite3VdbeAddOp4(pVdbe, OP_TableLock, p1, p->iTab, p->isWriteLock,
+                      p->zName, P4_STATIC);
   }
 }
 #else
@@ -50880,12 +57981,6 @@ SQLITE_PRIVATE void sqlite3FinishCoding(Parse *pParse){
   if( db->mallocFailed ) return;
   if( pParse->nested ) return;
   if( pParse->nErr ) return;
-  if( !pParse->pVdbe ){
-    if( pParse->rc==SQLITE_OK && pParse->nErr ){
-      pParse->rc = SQLITE_ERROR;
-      return;
-    }
-  }
 
   /* Begin by generating some termination code at the end of the
   ** vdbe program
@@ -50911,9 +58006,13 @@ SQLITE_PRIVATE void sqlite3FinishCoding(Parse *pParse){
         sqlite3VdbeAddOp2(v,OP_VerifyCookie, iDb, pParse->cookieValue[iDb]);
       }
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-      if( pParse->pVirtualLock ){
-        char *vtab = (char *)pParse->pVirtualLock->pVtab;
-        sqlite3VdbeAddOp4(v, OP_VBegin, 0, 0, 0, vtab, P4_VTAB);
+      {
+        int i;
+        for(i=0; inVtabLock; i++){
+          char *vtab = (char *)pParse->apVtabLock[i]->pVtab;
+          sqlite3VdbeAddOp4(v, OP_VBegin, 0, 0, 0, vtab, P4_VTAB);
+        }
+        pParse->nVtabLock = 0;
       }
 #endif
 
@@ -50946,6 +58045,7 @@ SQLITE_PRIVATE void sqlite3FinishCoding(Parse *pParse){
     FILE *trace = (db->flags & SQLITE_VdbeTrace)!=0 ? stdout : 0;
     sqlite3VdbeTrace(v, trace);
 #endif
+    assert( pParse->disableColCache==0 );  /* Disables and re-enables match */
     sqlite3VdbeMakeReady(v, pParse->nVar, pParse->nMem+3,
                          pParse->nTab+3, pParse->explain);
     pParse->rc = SQLITE_DONE;
@@ -50976,23 +58076,25 @@ SQLITE_PRIVATE void sqlite3FinishCoding(Parse *pParse){
 SQLITE_PRIVATE void sqlite3NestedParse(Parse *pParse, const char *zFormat, ...){
   va_list ap;
   char *zSql;
+  char *zErrMsg = 0;
+  sqlite3 *db = pParse->db;
 # define SAVE_SZ  (sizeof(Parse) - offsetof(Parse,nVar))
   char saveBuf[SAVE_SZ];
 
   if( pParse->nErr ) return;
   assert( pParse->nested<10 );  /* Nesting should only be of limited depth */
   va_start(ap, zFormat);
-  zSql = sqlite3VMPrintf(pParse->db, zFormat, ap);
+  zSql = sqlite3VMPrintf(db, zFormat, ap);
   va_end(ap);
   if( zSql==0 ){
-    pParse->db->mallocFailed = 1;
     return;   /* A malloc must have failed */
   }
   pParse->nested++;
   memcpy(saveBuf, &pParse->nVar, SAVE_SZ);
   memset(&pParse->nVar, 0, SAVE_SZ);
-  sqlite3RunParser(pParse, zSql, 0);
-  sqlite3_free(zSql);
+  sqlite3RunParser(pParse, zSql, &zErrMsg);
+  sqlite3DbFree(db, zErrMsg);
+  sqlite3DbFree(db, zSql);
   memcpy(&pParse->nVar, saveBuf, SAVE_SZ);
   pParse->nested--;
 }
@@ -51012,11 +58114,13 @@ SQLITE_PRIVATE void sqlite3NestedParse(Parse *pParse, const char *zFormat, ...){
 SQLITE_PRIVATE Table *sqlite3FindTable(sqlite3 *db, const char *zName, const char *zDatabase){
   Table *p = 0;
   int i;
+  int nName;
   assert( zName!=0 );
+  nName = sqlite3Strlen(db, zName) + 1;
   for(i=OMIT_TEMPDB; inDb; i++){
     int j = (i<2) ? i^1 : i;   /* Search TEMP before MAIN */
     if( zDatabase!=0 && sqlite3StrICmp(zDatabase, db->aDb[j].zName) ) continue;
-    p = sqlite3HashFind(&db->aDb[j].pSchema->tblHash, zName, strlen(zName)+1);
+    p = sqlite3HashFind(&db->aDb[j].pSchema->tblHash, zName, nName);
     if( p ) break;
   }
   return p;
@@ -51074,13 +58178,14 @@ SQLITE_PRIVATE Table *sqlite3LocateTable(
 SQLITE_PRIVATE Index *sqlite3FindIndex(sqlite3 *db, const char *zName, const char *zDb){
   Index *p = 0;
   int i;
+  int nName = sqlite3Strlen(db, zName)+1;
   for(i=OMIT_TEMPDB; inDb; i++){
     int j = (i<2) ? i^1 : i;  /* Search TEMP before MAIN */
     Schema *pSchema = db->aDb[j].pSchema;
     if( zDb && sqlite3StrICmp(zDb, db->aDb[j].zName) ) continue;
     assert( pSchema || (j==1 && !db->aDb[1].pBt) );
     if( pSchema ){
-      p = sqlite3HashFind(&pSchema->idxHash, zName, strlen(zName)+1);
+      p = sqlite3HashFind(&pSchema->idxHash, zName, nName);
     }
     if( p ) break;
   }
@@ -51091,8 +58196,9 @@ SQLITE_PRIVATE Index *sqlite3FindIndex(sqlite3 *db, const char *zName, const cha
 ** Reclaim the memory used by an index
 */
 static void freeIndex(Index *p){
-  sqlite3_free(p->zColAff);
-  sqlite3_free(p);
+  sqlite3 *db = p->pTable->db;
+  sqlite3DbFree(db, p->zColAff);
+  sqlite3DbFree(db, p);
 }
 
 /*
@@ -51107,7 +58213,7 @@ static void sqliteDeleteIndex(Index *p){
   Index *pOld;
   const char *zName = p->zName;
 
-  pOld = sqlite3HashInsert(&p->pSchema->idxHash, zName, strlen( zName)+1, 0);
+  pOld = sqlite3HashInsert(&p->pSchema->idxHash, zName, strlen(zName)+1, 0);
   assert( pOld==0 || pOld==p );
   freeIndex(p);
 }
@@ -51123,7 +58229,7 @@ SQLITE_PRIVATE void sqlite3UnlinkAndDeleteIndex(sqlite3 *db, int iDb, const char
   int len;
   Hash *pHash = &db->aDb[iDb].pSchema->idxHash;
 
-  len = strlen(zIdxName);
+  len = sqlite3Strlen(db, zIdxName);
   pIndex = sqlite3HashInsert(pHash, zIdxName, len+1, 0);
   if( pIndex ){
     if( pIndex->pTable->pIndex==pIndex ){
@@ -51186,7 +58292,7 @@ SQLITE_PRIVATE void sqlite3ResetInternalSchema(sqlite3 *db, int iDb){
   for(i=j=2; inDb; i++){
     struct Db *pDb = &db->aDb[i];
     if( pDb->pBt==0 ){
-      sqlite3_free(pDb->zName);
+      sqlite3DbFree(db, pDb->zName);
       pDb->zName = 0;
       continue;
     }
@@ -51199,7 +58305,7 @@ SQLITE_PRIVATE void sqlite3ResetInternalSchema(sqlite3 *db, int iDb){
   db->nDb = j;
   if( db->nDb<=2 && db->aDb!=db->aDbStatic ){
     memcpy(db->aDbStatic, db->aDb, 2*sizeof(db->aDb[0]));
-    sqlite3_free(db->aDb);
+    sqlite3DbFree(db, db->aDb);
     db->aDb = db->aDbStatic;
   }
 }
@@ -51217,15 +58323,16 @@ SQLITE_PRIVATE void sqlite3CommitInternalChanges(sqlite3 *db){
 static void sqliteResetColumnNames(Table *pTable){
   int i;
   Column *pCol;
+  sqlite3 *db = pTable->db;
   assert( pTable!=0 );
   if( (pCol = pTable->aCol)!=0 ){
     for(i=0; inCol; i++, pCol++){
-      sqlite3_free(pCol->zName);
-      sqlite3ExprDelete(pCol->pDflt);
-      sqlite3_free(pCol->zType);
-      sqlite3_free(pCol->zColl);
+      sqlite3DbFree(db, pCol->zName);
+      sqlite3ExprDelete(db, pCol->pDflt);
+      sqlite3DbFree(db, pCol->zType);
+      sqlite3DbFree(db, pCol->zColl);
     }
-    sqlite3_free(pTable->aCol);
+    sqlite3DbFree(db, pTable->aCol);
   }
   pTable->aCol = 0;
   pTable->nCol = 0;
@@ -51244,8 +58351,10 @@ static void sqliteResetColumnNames(Table *pTable){
 SQLITE_PRIVATE void sqlite3DeleteTable(Table *pTable){
   Index *pIndex, *pNext;
   FKey *pFKey, *pNextFKey;
+  sqlite3 *db;
 
   if( pTable==0 ) return;
+  db = pTable->db;
 
   /* Do not delete the table until the reference count reaches zero. */
   pTable->nRef--;
@@ -51270,21 +58379,21 @@ SQLITE_PRIVATE void sqlite3DeleteTable(Table *pTable){
     pNextFKey = pFKey->pNextFrom;
     assert( sqlite3HashFind(&pTable->pSchema->aFKey,
                            pFKey->zTo, strlen(pFKey->zTo)+1)!=pFKey );
-    sqlite3_free(pFKey);
+    sqlite3DbFree(db, pFKey);
   }
 #endif
 
   /* Delete the Table structure itself.
   */
   sqliteResetColumnNames(pTable);
-  sqlite3_free(pTable->zName);
-  sqlite3_free(pTable->zColAff);
-  sqlite3SelectDelete(pTable->pSelect);
+  sqlite3DbFree(db, pTable->zName);
+  sqlite3DbFree(db, pTable->zColAff);
+  sqlite3SelectDelete(db, pTable->pSelect);
 #ifndef SQLITE_OMIT_CHECK
-  sqlite3ExprDelete(pTable->pCheck);
+  sqlite3ExprDelete(db, pTable->pCheck);
 #endif
   sqlite3VtabClear(pTable);
-  sqlite3_free(pTable);
+  sqlite3DbFree(db, pTable);
 }
 
 /*
@@ -51349,8 +58458,8 @@ SQLITE_PRIVATE char *sqlite3NameFromToken(sqlite3 *db, Token *pName){
 SQLITE_PRIVATE void sqlite3OpenMasterTable(Parse *p, int iDb){
   Vdbe *v = sqlite3GetVdbe(p);
   sqlite3TableLock(p, iDb, MASTER_ROOT, 1, SCHEMA_TABLE(iDb));
+  sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, 5);/* sqlite_master has 5 columns */
   sqlite3VdbeAddOp3(v, OP_OpenWrite, 0, MASTER_ROOT, iDb);
-  sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, 5); /* sqlite_master has 5 columns */
 }
 
 /*
@@ -51374,7 +58483,7 @@ SQLITE_PRIVATE int sqlite3FindDb(sqlite3 *db, Token *pName){
         break;
       }
     }
-    sqlite3_free(zName);
+    sqlite3DbFree(db, zName);
   }
   return i;
 }
@@ -51565,6 +58674,7 @@ SQLITE_PRIVATE void sqlite3StartTable(
   pTable->iPKey = -1;
   pTable->pSchema = db->aDb[iDb].pSchema;
   pTable->nRef = 1;
+  pTable->db = db;
   if( pParse->pNewTable ) sqlite3DeleteTable(pParse->pNewTable);
   pParse->pNewTable = pTable;
 
@@ -51644,7 +58754,7 @@ SQLITE_PRIVATE void sqlite3StartTable(
 
   /* If an error occurs, we jump here */
 begin_table_error:
-  sqlite3_free(zName);
+  sqlite3DbFree(db, zName);
   return;
 }
 
@@ -51674,17 +58784,20 @@ SQLITE_PRIVATE void sqlite3AddColumn(Parse *pParse, Token *pName){
   int i;
   char *z;
   Column *pCol;
+  sqlite3 *db = pParse->db;
   if( (p = pParse->pNewTable)==0 ) return;
-  if( p->nCol+1>SQLITE_MAX_COLUMN ){
+#if SQLITE_MAX_COLUMN
+  if( p->nCol+1>db->aLimit[SQLITE_LIMIT_COLUMN] ){
     sqlite3ErrorMsg(pParse, "too many columns on %s", p->zName);
     return;
   }
+#endif
   z = sqlite3NameFromToken(pParse->db, pName);
   if( z==0 ) return;
   for(i=0; inCol; i++){
     if( STRICMP(z, p->aCol[i].zName) ){
       sqlite3ErrorMsg(pParse, "duplicate column name: %s", z);
-      sqlite3_free(z);
+      sqlite3DbFree(db, z);
       return;
     }
   }
@@ -51692,7 +58805,7 @@ SQLITE_PRIVATE void sqlite3AddColumn(Parse *pParse, Token *pName){
     Column *aNew;
     aNew = sqlite3DbRealloc(pParse->db,p->aCol,(p->nCol+8)*sizeof(p->aCol[0]));
     if( aNew==0 ){
-      sqlite3_free(z);
+      sqlite3DbFree(db, z);
       return;
     }
     p->aCol = aNew;
@@ -51799,13 +58912,15 @@ SQLITE_PRIVATE void sqlite3AddColumnType(Parse *pParse, Token *pType){
   Table *p;
   int i;
   Column *pCol;
+  sqlite3 *db;
 
   if( (p = pParse->pNewTable)==0 ) return;
   i = p->nCol-1;
   if( i<0 ) return;
   pCol = &p->aCol[i];
-  sqlite3_free(pCol->zType);
-  pCol->zType = sqlite3NameFromToken(pParse->db, pType);
+  db = pParse->db;
+  sqlite3DbFree(db, pCol->zType);
+  pCol->zType = sqlite3NameFromToken(db, pType);
   pCol->affinity = sqlite3AffinityType(pType);
 }
 
@@ -51822,6 +58937,7 @@ SQLITE_PRIVATE void sqlite3AddColumnType(Parse *pParse, Token *pType){
 SQLITE_PRIVATE void sqlite3AddDefaultValue(Parse *pParse, Expr *pExpr){
   Table *p;
   Column *pCol;
+  sqlite3 *db = pParse->db;
   if( (p = pParse->pNewTable)!=0 ){
     pCol = &(p->aCol[p->nCol-1]);
     if( !sqlite3ExprIsConstantOrFunction(pExpr) ){
@@ -51829,15 +58945,14 @@ SQLITE_PRIVATE void sqlite3AddDefaultValue(Parse *pParse, Expr *pExpr){
           pCol->zName);
     }else{
       Expr *pCopy;
-      sqlite3 *db = pParse->db;
-      sqlite3ExprDelete(pCol->pDflt);
+      sqlite3ExprDelete(db, pCol->pDflt);
       pCol->pDflt = pCopy = sqlite3ExprDup(db, pExpr);
       if( pCopy ){
         sqlite3TokenCopy(db, &pCopy->span, &pExpr->span);
       }
     }
   }
-  sqlite3ExprDelete(pExpr);
+  sqlite3ExprDelete(db, pExpr);
 }
 
 /*
@@ -51869,12 +58984,12 @@ SQLITE_PRIVATE void sqlite3AddPrimaryKey(
   char *zType = 0;
   int iCol = -1, i;
   if( pTab==0 || IN_DECLARE_VTAB ) goto primary_key_exit;
-  if( pTab->hasPrimKey ){
+  if( pTab->tabFlags & TF_HasPrimaryKey ){
     sqlite3ErrorMsg(pParse, 
       "table \"%s\" has more than one primary key", pTab->zName);
     goto primary_key_exit;
   }
-  pTab->hasPrimKey = 1;
+  pTab->tabFlags |= TF_HasPrimaryKey;
   if( pList==0 ){
     iCol = pTab->nCol - 1;
     pTab->aCol[iCol].isPrimKey = 1;
@@ -51898,7 +59013,8 @@ SQLITE_PRIVATE void sqlite3AddPrimaryKey(
         && sortOrder==SQLITE_SO_ASC ){
     pTab->iPKey = iCol;
     pTab->keyConf = onError;
-    pTab->autoInc = autoInc;
+    assert( autoInc==0 || autoInc==1 );
+    pTab->tabFlags |= autoInc*TF_Autoincrement;
   }else if( autoInc ){
 #ifndef SQLITE_OMIT_AUTOINCREMENT
     sqlite3ErrorMsg(pParse, "AUTOINCREMENT is only allowed on an "
@@ -51910,7 +59026,7 @@ SQLITE_PRIVATE void sqlite3AddPrimaryKey(
   }
 
 primary_key_exit:
-  sqlite3ExprListDelete(pList);
+  sqlite3ExprListDelete(pParse->db, pList);
   return;
 }
 
@@ -51921,9 +59037,9 @@ SQLITE_PRIVATE void sqlite3AddCheckConstraint(
   Parse *pParse,    /* Parsing context */
   Expr *pCheckExpr  /* The check expression */
 ){
+  sqlite3 *db = pParse->db;
 #ifndef SQLITE_OMIT_CHECK
   Table *pTab = pParse->pNewTable;
-  sqlite3 *db = pParse->db;
   if( pTab && !IN_DECLARE_VTAB ){
     /* The CHECK expression must be duplicated so that tokens refer
     ** to malloced space and not the (ephemeral) text of the CREATE TABLE
@@ -51932,7 +59048,7 @@ SQLITE_PRIVATE void sqlite3AddCheckConstraint(
                                   sqlite3ExprDup(db, pCheckExpr));
   }
 #endif
-  sqlite3ExprDelete(pCheckExpr);
+  sqlite3ExprDelete(db, pCheckExpr);
 }
 
 /*
@@ -51943,11 +59059,12 @@ SQLITE_PRIVATE void sqlite3AddCollateType(Parse *pParse, Token *pToken){
   Table *p;
   int i;
   char *zColl;              /* Dequoted name of collation sequence */
+  sqlite3 *db;
 
   if( (p = pParse->pNewTable)==0 ) return;
   i = p->nCol-1;
-
-  zColl = sqlite3NameFromToken(pParse->db, pToken);
+  db = pParse->db;
+  zColl = sqlite3NameFromToken(db, pToken);
   if( !zColl ) return;
 
   if( sqlite3LocateCollSeq(pParse, zColl, -1) ){
@@ -51965,7 +59082,7 @@ SQLITE_PRIVATE void sqlite3AddCollateType(Parse *pParse, Token *pToken){
       }
     }
   }else{
-    sqlite3_free(zColl);
+    sqlite3DbFree(db, zColl);
   }
 }
 
@@ -51998,7 +59115,7 @@ SQLITE_PRIVATE CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char *zName, i
     pColl = sqlite3GetCollSeq(db, pColl, zName, nName);
     if( !pColl ){
       if( nName<0 ){
-        nName = strlen(zName);
+        nName = sqlite3Strlen(db, zName);
       }
       sqlite3ErrorMsg(pParse, "no such collation sequence: %.*s", nName, zName);
       pColl = 0;
@@ -52102,7 +59219,7 @@ static char *createTableStmt(sqlite3 *db, Table *p, int isTemp){
     zEnd = "\n)";
   }
   n += 35 + 6*p->nCol;
-  zStmt = sqlite3_malloc( n );
+  zStmt = sqlite3Malloc( n );
   if( zStmt==0 ){
     db->mallocFailed = 1;
     return 0;
@@ -52184,7 +59301,7 @@ SQLITE_PRIVATE void sqlite3EndTable(
     sNC.pParse = pParse;
     sNC.pSrcList = &sSrc;
     sNC.isCheck = 1;
-    if( sqlite3ExprResolveNames(&sNC, p->pCheck) ){
+    if( sqlite3ResolveExprNames(&sNC, p->pCheck) ){
       return;
     }
   }
@@ -52252,14 +59369,15 @@ SQLITE_PRIVATE void sqlite3EndTable(
       SelectDest dest;
       Table *pSelTab;
 
+      assert(pParse->nTab==0);
       sqlite3VdbeAddOp3(v, OP_OpenWrite, 1, pParse->regRoot, iDb);
       sqlite3VdbeChangeP5(v, 1);
       pParse->nTab = 2;
       sqlite3SelectDestInit(&dest, SRT_Table, 1);
-      sqlite3Select(pParse, pSelect, &dest, 0, 0, 0, 0);
+      sqlite3Select(pParse, pSelect, &dest);
       sqlite3VdbeAddOp1(v, OP_Close, 1);
       if( pParse->nErr==0 ){
-        pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSelect);
+        pSelTab = sqlite3ResultSetOfSelect(pParse, pSelect);
         if( pSelTab==0 ) return;
         assert( p->aCol==0 );
         p->nCol = pSelTab->nCol;
@@ -52298,14 +59416,14 @@ SQLITE_PRIVATE void sqlite3EndTable(
       zStmt,
       pParse->regRowid
     );
-    sqlite3_free(zStmt);
+    sqlite3DbFree(db, zStmt);
     sqlite3ChangeCookie(pParse, iDb);
 
 #ifndef SQLITE_OMIT_AUTOINCREMENT
     /* Check to see if we need to create an sqlite_sequence table for
     ** keeping track of autoincrement keys.
     */
-    if( p->autoInc ){
+    if( p->tabFlags & TF_Autoincrement ){
       Db *pDb = &db->aDb[iDb];
       if( pDb->pSchema->pSeqTab==0 ){
         sqlite3NestedParse(pParse,
@@ -52388,13 +59506,13 @@ SQLITE_PRIVATE void sqlite3CreateView(
 
   if( pParse->nVar>0 ){
     sqlite3ErrorMsg(pParse, "parameters are not allowed in views");
-    sqlite3SelectDelete(pSelect);
+    sqlite3SelectDelete(db, pSelect);
     return;
   }
   sqlite3StartTable(pParse, pName1, pName2, isTemp, 1, 0, noErr);
   p = pParse->pNewTable;
   if( p==0 || pParse->nErr ){
-    sqlite3SelectDelete(pSelect);
+    sqlite3SelectDelete(db, pSelect);
     return;
   }
   sqlite3TwoPartName(pParse, pName1, pName2, &pName);
@@ -52402,7 +59520,7 @@ SQLITE_PRIVATE void sqlite3CreateView(
   if( sqlite3FixInit(&sFix, pParse, iDb, "view", pName)
     && sqlite3FixSelect(&sFix, pSelect)
   ){
-    sqlite3SelectDelete(pSelect);
+    sqlite3SelectDelete(db, pSelect);
     return;
   }
 
@@ -52412,7 +59530,7 @@ SQLITE_PRIVATE void sqlite3CreateView(
   ** they will persist after the current sqlite3_exec() call returns.
   */
   p->pSelect = sqlite3SelectDup(db, pSelect);
-  sqlite3SelectDelete(pSelect);
+  sqlite3SelectDelete(db, pSelect);
   if( db->mallocFailed ){
     return;
   }
@@ -52501,10 +59619,10 @@ SQLITE_PRIVATE int sqlite3ViewGetColumnNames(Parse *pParse, Table *pTable){
 #ifndef SQLITE_OMIT_AUTHORIZATION
     xAuth = db->xAuth;
     db->xAuth = 0;
-    pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSel);
+    pSelTab = sqlite3ResultSetOfSelect(pParse, pSel);
     db->xAuth = xAuth;
 #else
-    pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSel);
+    pSelTab = sqlite3ResultSetOfSelect(pParse, pSel);
 #endif
     pParse->nTab = n;
     if( pSelTab ){
@@ -52519,7 +59637,7 @@ SQLITE_PRIVATE int sqlite3ViewGetColumnNames(Parse *pParse, Table *pTable){
       pTable->nCol = 0;
       nErr++;
     }
-    sqlite3SelectDelete(pSel);
+    sqlite3SelectDelete(db, pSel);
   } else {
     nErr++;
   }
@@ -52738,7 +59856,7 @@ SQLITE_PRIVATE void sqlite3DropTable(Parse *pParse, SrcList *pName, int isView,
     }
   }
 #endif
-  if( pTab->readOnly || pTab==db->aDb[iDb].pSchema->pSeqTab ){
+  if( sqlite3StrNICmp(pTab->zName, "sqlite_", 7)==0 ){
     sqlite3ErrorMsg(pParse, "table %s may not be dropped", pTab->zName);
     goto exit_drop_table;
   }
@@ -52793,7 +59911,7 @@ SQLITE_PRIVATE void sqlite3DropTable(Parse *pParse, SrcList *pName, int isView,
     ** at the btree level, in case the sqlite_sequence table needs to
     ** move as a result of the drop (can happen in auto-vacuum mode).
     */
-    if( pTab->autoInc ){
+    if( pTab->tabFlags & TF_Autoincrement ){
       sqlite3NestedParse(pParse,
         "DELETE FROM %s.sqlite_sequence WHERE name=%Q",
         pDb->zName, pTab->zName
@@ -52811,6 +59929,14 @@ SQLITE_PRIVATE void sqlite3DropTable(Parse *pParse, SrcList *pName, int isView,
     sqlite3NestedParse(pParse, 
         "DELETE FROM %Q.%s WHERE tbl_name=%Q and type!='trigger'",
         pDb->zName, SCHEMA_TABLE(iDb), pTab->zName);
+
+    /* Drop any statistics from the sqlite_stat1 table, if it exists */
+    if( sqlite3FindTable(db, "sqlite_stat1", db->aDb[iDb].zName) ){
+      sqlite3NestedParse(pParse,
+        "DELETE FROM %Q.sqlite_stat1 WHERE tbl=%Q", pDb->zName, pTab->zName
+      );
+    }
+
     if( !isView && !IsVirtual(pTab) ){
       destroyTable(pParse, pTab);
     }
@@ -52827,7 +59953,7 @@ SQLITE_PRIVATE void sqlite3DropTable(Parse *pParse, SrcList *pName, int isView,
   sqliteViewResetAll(db, iDb);
 
 exit_drop_table:
-  sqlite3SrcListDelete(pName);
+  sqlite3SrcListDelete(db, pName);
 }
 
 /*
@@ -52855,6 +59981,7 @@ SQLITE_PRIVATE void sqlite3CreateForeignKey(
   ExprList *pToCol,    /* Columns in the other table */
   int flags            /* Conflict resolution algorithms. */
 ){
+  sqlite3 *db = pParse->db;
 #ifndef SQLITE_OMIT_FOREIGN_KEY
   FKey *pFKey = 0;
   Table *p = pParse->pNewTable;
@@ -52889,7 +60016,7 @@ SQLITE_PRIVATE void sqlite3CreateForeignKey(
       nByte += strlen(pToCol->a[i].zName) + 1;
     }
   }
-  pFKey = sqlite3DbMallocZero(pParse->db, nByte );
+  pFKey = sqlite3DbMallocZero(db, nByte );
   if( pFKey==0 ){
     goto fk_end;
   }
@@ -52943,10 +60070,10 @@ SQLITE_PRIVATE void sqlite3CreateForeignKey(
   pFKey = 0;
 
 fk_end:
-  sqlite3_free(pFKey);
+  sqlite3DbFree(db, pFKey);
 #endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */
-  sqlite3ExprListDelete(pFromCol);
-  sqlite3ExprListDelete(pToCol);
+  sqlite3ExprListDelete(db, pFromCol);
+  sqlite3ExprListDelete(db, pToCol);
 }
 
 /*
@@ -53016,7 +60143,7 @@ static void sqlite3RefillIndex(Parse *pParse, Index *pIndex, int memRootPage){
   sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
   addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iTab, 0);
   regRecord = sqlite3GetTempReg(pParse);
-  regIdxKey = sqlite3GenerateIndexKey(pParse, pIndex, iTab, regRecord);
+  regIdxKey = sqlite3GenerateIndexKey(pParse, pIndex, iTab, regRecord, 1);
   if( pIndex->onError!=OE_None ){
     int j1, j2;
     int regRowid;
@@ -53024,7 +60151,7 @@ static void sqlite3RefillIndex(Parse *pParse, Index *pIndex, int memRootPage){
     regRowid = regIdxKey + pIndex->nColumn;
     j1 = sqlite3VdbeAddOp3(v, OP_IsNull, regIdxKey, 0, pIndex->nColumn);
     j2 = sqlite3VdbeAddOp4(v, OP_IsUnique, iIdx,
-                           0, regRowid, (char*)(sqlite3_intptr_t)regRecord, P4_INT32);
+                           0, regRowid, SQLITE_INT_TO_PTR(regRecord), P4_INT32);
     sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, OE_Abort, 0,
                     "indexed columns are not unique", P4_STATIC);
     sqlite3VdbeJumpHere(v, j1);
@@ -53129,7 +60256,7 @@ SQLITE_PRIVATE void sqlite3CreateIndex(
   pDb = &db->aDb[iDb];
 
   if( pTab==0 || pParse->nErr ) goto exit_create_index;
-  if( pTab->readOnly ){
+  if( sqlite3StrNICmp(pTab->zName, "sqlite_", 7)==0 ){
     sqlite3ErrorMsg(pParse, "table %s may not be indexed", pTab->zName);
     goto exit_create_index;
   }
@@ -53180,15 +60307,11 @@ SQLITE_PRIVATE void sqlite3CreateIndex(
       goto exit_create_index;
     }
   }else{
-    char zBuf[30];
     int n;
     Index *pLoop;
     for(pLoop=pTab->pIndex, n=1; pLoop; pLoop=pLoop->pNext, n++){}
-    sqlite3_snprintf(sizeof(zBuf),zBuf,"_%d",n);
-    zName = 0;
-    sqlite3SetString(&zName, "sqlite_autoindex_", pTab->zName, zBuf, (char*)0);
+    zName = sqlite3MPrintf(db, "sqlite_autoindex_%s_%d", pTab->zName, n);
     if( zName==0 ){
-      db->mallocFailed = 1;
       goto exit_create_index;
     }
   }
@@ -53225,9 +60348,10 @@ SQLITE_PRIVATE void sqlite3CreateIndex(
   ** specified collation sequence names.
   */
   for(i=0; inExpr; i++){
-    Expr *pExpr = pList->a[i].pExpr;
-    if( pExpr ){
-      nExtra += (1 + strlen(pExpr->pColl->zName));
+    Expr *pExpr;
+    CollSeq *pColl;
+    if( (pExpr = pList->a[i].pExpr)!=0 && (pColl = pExpr->pColl)!=0 ){
+      nExtra += (1 + strlen(pColl->zName));
     }
   }
 
@@ -53294,7 +60418,7 @@ SQLITE_PRIVATE void sqlite3CreateIndex(
     ** break backwards compatibility - it needs to be a warning.
     */
     pIndex->aiColumn[i] = j;
-    if( pListItem->pExpr ){
+    if( pListItem->pExpr && pListItem->pExpr->pColl ){
       assert( pListItem->pExpr->pColl );
       zColl = zExtra;
       sqlite3_snprintf(nExtra, zExtra, "%s", pListItem->pExpr->pColl->zName);
@@ -53437,7 +60561,7 @@ SQLITE_PRIVATE void sqlite3CreateIndex(
         iMem,
         zStmt
     );
-    sqlite3_free(zStmt);
+    sqlite3DbFree(db, zStmt);
 
     /* Fill the index with data and reparse the schema. Code an OP_Expire
     ** to invalidate all pre-compiled statements.
@@ -53477,9 +60601,9 @@ exit_create_index:
   if( pIndex ){
     freeIndex(pIndex);
   }
-  sqlite3ExprListDelete(pList);
-  sqlite3SrcListDelete(pTblName);
-  sqlite3_free(zName);
+  sqlite3ExprListDelete(db, pList);
+  sqlite3SrcListDelete(db, pTblName);
+  sqlite3DbFree(db, zName);
   return;
 }
 
@@ -53596,13 +60720,19 @@ SQLITE_PRIVATE void sqlite3DropIndex(Parse *pParse, SrcList *pName, int ifExists
        db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
        pIndex->zName
     );
+    if( sqlite3FindTable(db, "sqlite_stat1", db->aDb[iDb].zName) ){
+      sqlite3NestedParse(pParse,
+        "DELETE FROM %Q.sqlite_stat1 WHERE idx=%Q",
+        db->aDb[iDb].zName, pIndex->zName
+      );
+    }
     sqlite3ChangeCookie(pParse, iDb);
     destroyRootPage(pParse, pIndex->tnum, iDb);
     sqlite3VdbeAddOp4(v, OP_DropIndex, iDb, 0, 0, pIndex->zName, 0);
   }
 
 exit_drop_index:
-  sqlite3SrcListDelete(pName);
+  sqlite3SrcListDelete(db, pName);
 }
 
 /*
@@ -53672,7 +60802,7 @@ SQLITE_PRIVATE IdList *sqlite3IdListAppend(sqlite3 *db, IdList *pList, Token *pT
       &i
   );
   if( i<0 ){
-    sqlite3IdListDelete(pList);
+    sqlite3IdListDelete(db, pList);
     return 0;
   }
   pList->a[i].zName = sqlite3NameFromToken(db, pToken);
@@ -53682,14 +60812,14 @@ SQLITE_PRIVATE IdList *sqlite3IdListAppend(sqlite3 *db, IdList *pList, Token *pT
 /*
 ** Delete an IdList.
 */
-SQLITE_PRIVATE void sqlite3IdListDelete(IdList *pList){
+SQLITE_PRIVATE void sqlite3IdListDelete(sqlite3 *db, IdList *pList){
   int i;
   if( pList==0 ) return;
   for(i=0; inId; i++){
-    sqlite3_free(pList->a[i].zName);
+    sqlite3DbFree(db, pList->a[i].zName);
   }
-  sqlite3_free(pList->a);
-  sqlite3_free(pList);
+  sqlite3DbFree(db, pList->a);
+  sqlite3DbFree(db, pList);
 }
 
 /*
@@ -53748,7 +60878,7 @@ SQLITE_PRIVATE SrcList *sqlite3SrcListAppend(
     pNew = sqlite3DbRealloc(db, pList,
                sizeof(*pList) + (pList->nAlloc-1)*sizeof(pList->a[0]) );
     if( pNew==0 ){
-      sqlite3SrcListDelete(pList);
+      sqlite3SrcListDelete(db, pList);
       return 0;
     }
     pList = pNew;
@@ -53766,7 +60896,6 @@ SQLITE_PRIVATE SrcList *sqlite3SrcListAppend(
   pItem->zName = sqlite3NameFromToken(db, pTable);
   pItem->zDatabase = sqlite3NameFromToken(db, pDatabase);
   pItem->iCursor = -1;
-  pItem->isPopulated = 0;
   pList->nSrc++;
   return pList;
 }
@@ -53792,20 +60921,21 @@ SQLITE_PRIVATE void sqlite3SrcListAssignCursors(Parse *pParse, SrcList *pList){
 /*
 ** Delete an entire SrcList including all its substructure.
 */
-SQLITE_PRIVATE void sqlite3SrcListDelete(SrcList *pList){
+SQLITE_PRIVATE void sqlite3SrcListDelete(sqlite3 *db, SrcList *pList){
   int i;
   struct SrcList_item *pItem;
   if( pList==0 ) return;
   for(pItem=pList->a, i=0; inSrc; i++, pItem++){
-    sqlite3_free(pItem->zDatabase);
-    sqlite3_free(pItem->zName);
-    sqlite3_free(pItem->zAlias);
+    sqlite3DbFree(db, pItem->zDatabase);
+    sqlite3DbFree(db, pItem->zName);
+    sqlite3DbFree(db, pItem->zAlias);
+    sqlite3DbFree(db, pItem->zIndex);
     sqlite3DeleteTable(pItem->pTab);
-    sqlite3SelectDelete(pItem->pSelect);
-    sqlite3ExprDelete(pItem->pOn);
-    sqlite3IdListDelete(pItem->pUsing);
+    sqlite3SelectDelete(db, pItem->pSelect);
+    sqlite3ExprDelete(db, pItem->pOn);
+    sqlite3IdListDelete(db, pItem->pUsing);
   }
-  sqlite3_free(pList);
+  sqlite3DbFree(db, pList);
 }
 
 /*
@@ -53838,9 +60968,9 @@ SQLITE_PRIVATE SrcList *sqlite3SrcListAppendFromTerm(
   sqlite3 *db = pParse->db;
   p = sqlite3SrcListAppend(db, p, pTable, pDatabase);
   if( p==0 || p->nSrc==0 ){
-    sqlite3ExprDelete(pOn);
-    sqlite3IdListDelete(pUsing);
-    sqlite3SelectDelete(pSubquery);
+    sqlite3ExprDelete(db, pOn);
+    sqlite3IdListDelete(db, pUsing);
+    sqlite3SelectDelete(db, pSubquery);
     return p;
   }
   pItem = &p->a[p->nSrc-1];
@@ -53854,6 +60984,24 @@ SQLITE_PRIVATE SrcList *sqlite3SrcListAppendFromTerm(
 }
 
 /*
+** Add an INDEXED BY or NOT INDEXED clause to the most recently added 
+** element of the source-list passed as the second argument.
+*/
+SQLITE_PRIVATE void sqlite3SrcListIndexedBy(Parse *pParse, SrcList *p, Token *pIndexedBy){
+  if( pIndexedBy && p && p->nSrc>0 ){
+    struct SrcList_item *pItem = &p->a[p->nSrc-1];
+    assert( pItem->notIndexed==0 && pItem->zIndex==0 );
+    if( pIndexedBy->n==1 && !pIndexedBy->z ){
+      /* A "NOT INDEXED" clause was supplied. See parse.y 
+      ** construct "indexed_opt" for details. */
+      pItem->notIndexed = 1;
+    }else{
+      pItem->zIndex = sqlite3NameFromToken(pParse->db, pIndexedBy);
+    }
+  }
+}
+
+/*
 ** When building up a FROM clause in the parser, the join operator
 ** is initially attached to the left operand.  But the code generator
 ** expects the join operator to be on the right operand.  This routine
@@ -53960,6 +61108,8 @@ SQLITE_PRIVATE int sqlite3OpenTempDatabase(Parse *pParse){
     }
     assert( (db->flags & SQLITE_InTrans)==0 || db->autoCommit );
     assert( db->aDb[1].pSchema );
+    sqlite3PagerJournalMode(sqlite3BtreePager(db->aDb[1].pBt),
+                            db->dfltJournalMode);
   }
   return 0;
 }
@@ -54143,11 +61293,11 @@ SQLITE_PRIVATE void sqlite3Reindex(Parse *pParse, Token *pName1, Token *pName2){
     if( pColl ){
       if( zColl ){
         reindexDatabases(pParse, zColl);
-        sqlite3_free(zColl);
+        sqlite3DbFree(db, zColl);
       }
       return;
     }
-    sqlite3_free(zColl);
+    sqlite3DbFree(db, zColl);
   }
   iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pObjName);
   if( iDb<0 ) return;
@@ -54157,11 +61307,11 @@ SQLITE_PRIVATE void sqlite3Reindex(Parse *pParse, Token *pName1, Token *pName2){
   pTab = sqlite3FindTable(db, z, zDb);
   if( pTab ){
     reindexTable(pParse, pTab, 0);
-    sqlite3_free(z);
+    sqlite3DbFree(db, z);
     return;
   }
   pIndex = sqlite3FindIndex(db, z, zDb);
-  sqlite3_free(z);
+  sqlite3DbFree(db, z);
   if( pIndex ){
     sqlite3BeginWriteOperation(pParse, 0, iDb);
     sqlite3RefillIndex(pParse, pIndex, -1);
@@ -54176,7 +61326,7 @@ SQLITE_PRIVATE void sqlite3Reindex(Parse *pParse, Token *pName1, Token *pName2){
 ** with OP_OpenRead or OP_OpenWrite to access database index pIdx.
 **
 ** If successful, a pointer to the new structure is returned. In this case
-** the caller is responsible for calling sqlite3_free() on the returned 
+** the caller is responsible for calling sqlite3DbFree(db, ) on the returned 
 ** pointer. If an error occurs (out of memory or missing collation 
 ** sequence), NULL is returned and the state of pParse updated to reflect
 ** the error.
@@ -54185,7 +61335,8 @@ SQLITE_PRIVATE KeyInfo *sqlite3IndexKeyinfo(Parse *pParse, Index *pIdx){
   int i;
   int nCol = pIdx->nColumn;
   int nBytes = sizeof(KeyInfo) + (nCol-1)*sizeof(CollSeq*) + nCol;
-  KeyInfo *pKey = (KeyInfo *)sqlite3DbMallocZero(pParse->db, nBytes);
+  sqlite3 *db = pParse->db;
+  KeyInfo *pKey = (KeyInfo *)sqlite3DbMallocZero(db, nBytes);
 
   if( pKey ){
     pKey->db = pParse->db;
@@ -54201,7 +61352,7 @@ SQLITE_PRIVATE KeyInfo *sqlite3IndexKeyinfo(Parse *pParse, Index *pIdx){
   }
 
   if( pParse->nErr ){
-    sqlite3_free(pKey);
+    sqlite3DbFree(db, pKey);
     pKey = 0;
   }
   return pKey;
@@ -54224,7 +61375,7 @@ SQLITE_PRIVATE KeyInfo *sqlite3IndexKeyinfo(Parse *pParse, Index *pIdx){
 ** This file contains functions used to access the internal hash tables
 ** of user defined functions and collation sequences.
 **
-** $Id: callback.c,v 1.23 2007/08/29 12:31:26 danielk1977 Exp $
+** $Id: callback.c,v 1.32 2008/10/10 17:41:29 drh Exp $
 */
 
 
@@ -54235,12 +61386,12 @@ SQLITE_PRIVATE KeyInfo *sqlite3IndexKeyinfo(Parse *pParse, Index *pIdx){
 */
 static void callCollNeeded(sqlite3 *db, const char *zName, int nName){
   assert( !db->xCollNeeded || !db->xCollNeeded16 );
-  if( nName<0 ) nName = strlen(zName);
+  if( nName<0 ) nName = sqlite3Strlen(db, zName);
   if( db->xCollNeeded ){
     char *zExternal = sqlite3DbStrNDup(db, zName, nName);
     if( !zExternal ) return;
     db->xCollNeeded(db->pCollNeededArg, db, (int)ENC(db), zExternal);
-    sqlite3_free(zExternal);
+    sqlite3DbFree(db, zExternal);
   }
 #ifndef SQLITE_OMIT_UTF16
   if( db->xCollNeeded16 ){
@@ -54368,7 +61519,7 @@ static CollSeq *findCollSeqEntry(
   int create
 ){
   CollSeq *pColl;
-  if( nName<0 ) nName = strlen(zName);
+  if( nName<0 ) nName = sqlite3Strlen(db, zName);
   pColl = sqlite3HashFind(&db->aCollSeq, zName, nName);
 
   if( 0==pColl && create ){
@@ -54392,7 +61543,7 @@ static CollSeq *findCollSeqEntry(
       assert( pDel==0 || pDel==pColl );
       if( pDel!=0 ){
         db->mallocFailed = 1;
-        sqlite3_free(pDel);
+        sqlite3DbFree(db, pDel);
         pColl = 0;
       }
     }
@@ -54432,6 +61583,87 @@ SQLITE_PRIVATE CollSeq *sqlite3FindCollSeq(
   return pColl;
 }
 
+/* During the search for the best function definition, this procedure
+** is called to test how well the function passed as the first argument
+** matches the request for a function with nArg arguments in a system
+** that uses encoding enc. The value returned indicates how well the
+** request is matched. A higher value indicates a better match.
+**
+** The returned value is always between 1 and 6, as follows:
+**
+** 1: A variable arguments function that prefers UTF-8 when a UTF-16
+**    encoding is requested, or vice versa.
+** 2: A variable arguments function that uses UTF-16BE when UTF-16LE is
+**    requested, or vice versa.
+** 3: A variable arguments function using the same text encoding.
+** 4: A function with the exact number of arguments requested that
+**    prefers UTF-8 when a UTF-16 encoding is requested, or vice versa.
+** 5: A function with the exact number of arguments requested that
+**    prefers UTF-16LE when UTF-16BE is requested, or vice versa.
+** 6: An exact match.
+**
+*/
+static int matchQuality(FuncDef *p, int nArg, u8 enc){
+  int match = 0;
+  if( p->nArg==-1 || p->nArg==nArg || nArg==-1 ){
+    match = 1;
+    if( p->nArg==nArg || nArg==-1 ){
+      match = 4;
+    }
+    if( enc==p->iPrefEnc ){
+      match += 2;
+    }
+    else if( (enc==SQLITE_UTF16LE && p->iPrefEnc==SQLITE_UTF16BE) ||
+             (enc==SQLITE_UTF16BE && p->iPrefEnc==SQLITE_UTF16LE) ){
+      match += 1;
+    }
+  }
+  return match;
+}
+
+/*
+** Search a FuncDefHash for a function with the given name.  Return
+** a pointer to the matching FuncDef if found, or 0 if there is no match.
+*/
+static FuncDef *functionSearch(
+  FuncDefHash *pHash,  /* Hash table to search */
+  int h,               /* Hash of the name */
+  const char *zFunc,   /* Name of function */
+  int nFunc            /* Number of bytes in zFunc */
+){
+  FuncDef *p;
+  for(p=pHash->a[h]; p; p=p->pHash){
+    if( sqlite3StrNICmp(p->zName, zFunc, nFunc)==0 && p->zName[nFunc]==0 ){
+      return p;
+    }
+  }
+  return 0;
+}
+
+/*
+** Insert a new FuncDef into a FuncDefHash hash table.
+*/
+SQLITE_PRIVATE void sqlite3FuncDefInsert(
+  FuncDefHash *pHash,  /* The hash table into which to insert */
+  FuncDef *pDef        /* The function definition to insert */
+){
+  FuncDef *pOther;
+  int nName = strlen(pDef->zName);
+  u8 c1 = (u8)pDef->zName[0];
+  int h = (sqlite3UpperToLower[c1] + nName) % ArraySize(pHash->a);
+  pOther = functionSearch(pHash, h, pDef->zName, nName);
+  if( pOther ){
+    pDef->pNext = pOther->pNext;
+    pOther->pNext = pDef;
+  }else{
+    pDef->pNext = 0;
+    pDef->pHash = pHash->a[h];
+    pHash->a[h] = pDef;
+  }
+}
+  
+  
+
 /*
 ** Locate a user function given a name, a number of arguments and a flag
 ** indicating whether the function prefers UTF-16 over UTF-8.  Return a
@@ -54461,70 +61693,60 @@ SQLITE_PRIVATE FuncDef *sqlite3FindFunction(
   int createFlag     /* Create new entry if true and does not otherwise exist */
 ){
   FuncDef *p;         /* Iterator variable */
-  FuncDef *pFirst;    /* First function with this name */
   FuncDef *pBest = 0; /* Best match found so far */
-  int bestmatch = 0;  
+  int bestScore = 0;  /* Score of best match */
+  int h;              /* Hash value */
 
 
   assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
   if( nArg<-1 ) nArg = -1;
+  h = (sqlite3UpperToLower[(u8)zName[0]] + nName) % ArraySize(db->aFunc.a);
 
-  pFirst = (FuncDef*)sqlite3HashFind(&db->aFunc, zName, nName);
-  for(p=pFirst; p; p=p->pNext){
-    /* During the search for the best function definition, bestmatch is set
-    ** as follows to indicate the quality of the match with the definition
-    ** pointed to by pBest:
-    **
-    ** 0: pBest is NULL. No match has been found.
-    ** 1: A variable arguments function that prefers UTF-8 when a UTF-16
-    **    encoding is requested, or vice versa.
-    ** 2: A variable arguments function that uses UTF-16BE when UTF-16LE is
-    **    requested, or vice versa.
-    ** 3: A variable arguments function using the same text encoding.
-    ** 4: A function with the exact number of arguments requested that
-    **    prefers UTF-8 when a UTF-16 encoding is requested, or vice versa.
-    ** 5: A function with the exact number of arguments requested that
-    **    prefers UTF-16LE when UTF-16BE is requested, or vice versa.
-    ** 6: An exact match.
-    **
-    ** A larger value of 'matchqual' indicates a more desirable match.
-    */
-    if( p->nArg==-1 || p->nArg==nArg || nArg==-1 ){
-      int match = 1;          /* Quality of this match */
-      if( p->nArg==nArg || nArg==-1 ){
-        match = 4;
-      }
-      if( enc==p->iPrefEnc ){
-        match += 2;
-      }
-      else if( (enc==SQLITE_UTF16LE && p->iPrefEnc==SQLITE_UTF16BE) ||
-               (enc==SQLITE_UTF16BE && p->iPrefEnc==SQLITE_UTF16LE) ){
-        match += 1;
-      }
+  /* First search for a match amongst the application-defined functions.
+  */
+  p = functionSearch(&db->aFunc, h, zName, nName);
+  while( p ){
+    int score = matchQuality(p, nArg, enc);
+    if( score>bestScore ){
+      pBest = p;
+      bestScore = score;
+    }
+    p = p->pNext;
+  }
 
-      if( match>bestmatch ){
+  /* If no match is found, search the built-in functions.
+  **
+  ** Except, if createFlag is true, that means that we are trying to
+  ** install a new function.  Whatever FuncDef structure is returned will
+  ** have fields overwritten with new information appropriate for the
+  ** new function.  But the FuncDefs for built-in functions are read-only.
+  ** So we must not search for built-ins when creating a new function.
+  */ 
+  if( !createFlag && !pBest ){
+    FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
+    p = functionSearch(pHash, h, zName, nName);
+    while( p ){
+      int score = matchQuality(p, nArg, enc);
+      if( score>bestScore ){
         pBest = p;
-        bestmatch = match;
+        bestScore = score;
       }
+      p = p->pNext;
     }
   }
 
-  /* If the createFlag parameter is true, and the seach did not reveal an
+  /* If the createFlag parameter is true and the search did not reveal an
   ** exact match for the name, number of arguments and encoding, then add a
   ** new entry to the hash table and return it.
   */
-  if( createFlag && bestmatch<6 && 
-      (pBest = sqlite3DbMallocZero(db, sizeof(*pBest)+nName))!=0 ){
+  if( createFlag && (bestScore<6 || pBest->nArg!=nArg) && 
+      (pBest = sqlite3DbMallocZero(db, sizeof(*pBest)+nName+1))!=0 ){
+    pBest->zName = (char *)&pBest[1];
     pBest->nArg = nArg;
-    pBest->pNext = pFirst;
     pBest->iPrefEnc = enc;
     memcpy(pBest->zName, zName, nName);
     pBest->zName[nName] = 0;
-    if( pBest==sqlite3HashInsert(&db->aFunc,pBest->zName,nName,(void*)pBest) ){
-      db->mallocFailed = 1;
-      sqlite3_free(pBest);
-      return 0;
-    }
+    sqlite3FuncDefInsert(&db->aFunc, pBest);
   }
 
   if( pBest && (pBest->xStep || pBest->xFunc || createFlag) ){
@@ -54535,9 +61757,11 @@ SQLITE_PRIVATE FuncDef *sqlite3FindFunction(
 
 /*
 ** Free all resources held by the schema structure. The void* argument points
-** at a Schema struct. This function does not call sqlite3_free() on the 
+** at a Schema struct. This function does not call sqlite3DbFree(db, ) on the 
 ** pointer itself, it just cleans up subsiduary resources (i.e. the contents
 ** of the schema hash tables).
+**
+** The Schema.cache_size variable is not cleared.
 */
 SQLITE_PRIVATE void sqlite3SchemaFree(void *p){
   Hash temp1;
@@ -54547,14 +61771,14 @@ SQLITE_PRIVATE void sqlite3SchemaFree(void *p){
 
   temp1 = pSchema->tblHash;
   temp2 = pSchema->trigHash;
-  sqlite3HashInit(&pSchema->trigHash, SQLITE_HASH_STRING, 0);
+  sqlite3HashInit(&pSchema->trigHash, 0);
   sqlite3HashClear(&pSchema->aFKey);
   sqlite3HashClear(&pSchema->idxHash);
   for(pElem=sqliteHashFirst(&temp2); pElem; pElem=sqliteHashNext(pElem)){
-    sqlite3DeleteTrigger((Trigger*)sqliteHashData(pElem));
+    sqlite3DeleteTrigger(0, (Trigger*)sqliteHashData(pElem));
   }
   sqlite3HashClear(&temp2);
-  sqlite3HashInit(&pSchema->tblHash, SQLITE_HASH_STRING, 0);
+  sqlite3HashInit(&pSchema->tblHash, 0);
   for(pElem=sqliteHashFirst(&temp1); pElem; pElem=sqliteHashNext(pElem)){
     Table *pTab = sqliteHashData(pElem);
     sqlite3DeleteTable(pTab);
@@ -54578,10 +61802,10 @@ SQLITE_PRIVATE Schema *sqlite3SchemaGet(sqlite3 *db, Btree *pBt){
   if( !p ){
     db->mallocFailed = 1;
   }else if ( 0==p->file_format ){
-    sqlite3HashInit(&p->tblHash, SQLITE_HASH_STRING, 0);
-    sqlite3HashInit(&p->idxHash, SQLITE_HASH_STRING, 0);
-    sqlite3HashInit(&p->trigHash, SQLITE_HASH_STRING, 0);
-    sqlite3HashInit(&p->aFKey, SQLITE_HASH_STRING, 1);
+    sqlite3HashInit(&p->tblHash, 0);
+    sqlite3HashInit(&p->idxHash, 0);
+    sqlite3HashInit(&p->trigHash, 0);
+    sqlite3HashInit(&p->aFKey, 1);
     p->enc = SQLITE_UTF8;
   }
   return p;
@@ -54603,7 +61827,7 @@ SQLITE_PRIVATE Schema *sqlite3SchemaGet(sqlite3 *db, Btree *pBt){
 ** This file contains C code routines that are called by the parser
 ** in order to generate code for DELETE FROM statements.
 **
-** $Id: delete.c,v 1.161 2008/02/12 16:52:14 drh Exp $
+** $Id: delete.c,v 1.182 2008/10/10 23:48:26 drh Exp $
 */
 
 /*
@@ -54612,16 +61836,17 @@ SQLITE_PRIVATE Schema *sqlite3SchemaGet(sqlite3 *db, Btree *pBt){
 ** are found, return a pointer to the last table.
 */
 SQLITE_PRIVATE Table *sqlite3SrcListLookup(Parse *pParse, SrcList *pSrc){
-  Table *pTab = 0;
-  int i;
-  struct SrcList_item *pItem;
-  for(i=0, pItem=pSrc->a; inSrc; i++, pItem++){
-    pTab = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase);
-    sqlite3DeleteTable(pItem->pTab);
-    pItem->pTab = pTab;
-    if( pTab ){
-      pTab->nRef++;
-    }
+  struct SrcList_item *pItem = pSrc->a;
+  Table *pTab;
+  assert( pItem && pSrc->nSrc==1 );
+  pTab = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase);
+  sqlite3DeleteTable(pItem->pTab);
+  pItem->pTab = pTab;
+  if( pTab ){
+    pTab->nRef++;
+  }
+  if( sqlite3IndexedByLookup(pParse, pItem) ){
+    pTab = 0;
   }
   return pTab;
 }
@@ -54632,7 +61857,8 @@ SQLITE_PRIVATE Table *sqlite3SrcListLookup(Parse *pParse, SrcList *pSrc){
 ** writable return 0;
 */
 SQLITE_PRIVATE int sqlite3IsReadOnly(Parse *pParse, Table *pTab, int viewOk){
-  if( (pTab->readOnly && (pParse->db->flags & SQLITE_WriteSchema)==0
+  if( ((pTab->tabFlags & TF_Readonly)!=0
+        && (pParse->db->flags & SQLITE_WriteSchema)==0
         && pParse->nested==0) 
 #ifndef SQLITE_OMIT_VIRTUALTABLE
       || (pTab->pMod && pTab->pMod->pModule->xUpdate==0)
@@ -54665,9 +61891,9 @@ SQLITE_PRIVATE void sqlite3OpenTable(
   v = sqlite3GetVdbe(p);
   assert( opcode==OP_OpenWrite || opcode==OP_OpenRead );
   sqlite3TableLock(p, iDb, pTab->tnum, (opcode==OP_OpenWrite), pTab->zName);
+  sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
   sqlite3VdbeAddOp3(v, opcode, iCur, pTab->tnum, iDb);
   VdbeComment((v, "%s", pTab->zName));
-  sqlite3VdbeAddOp2(v, OP_SetNumColumns, iCur, pTab->nCol);
 }
 
 
@@ -54679,30 +61905,122 @@ SQLITE_PRIVATE void sqlite3OpenTable(
 */
 SQLITE_PRIVATE void sqlite3MaterializeView(
   Parse *pParse,       /* Parsing context */
-  Select *pView,       /* View definition */
+  Table *pView,        /* View definition */
   Expr *pWhere,        /* Optional WHERE clause to be added */
-  u32 col_mask,        /* Render only the columns in this mask. */
   int iCur             /* Cursor number for ephemerial table */
 ){
   SelectDest dest;
   Select *pDup;
   sqlite3 *db = pParse->db;
 
-  pDup = sqlite3SelectDup(db, pView);
+  pDup = sqlite3SelectDup(db, pView->pSelect);
   if( pWhere ){
     SrcList *pFrom;
+    Token viewName;
     
     pWhere = sqlite3ExprDup(db, pWhere);
-    pFrom = sqlite3SrcListAppendFromTerm(pParse, 0, 0, 0, 0, pDup, 0, 0);
+    viewName.z = (u8*)pView->zName;
+    viewName.n = (unsigned int)strlen((const char*)viewName.z);
+    pFrom = sqlite3SrcListAppendFromTerm(pParse, 0, 0, 0, &viewName, pDup, 0,0);
     pDup = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
   }
-  sqlite3SelectMask(pParse, pDup, col_mask);
   sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
-  sqlite3Select(pParse, pDup, &dest, 0, 0, 0, 0);
-  sqlite3SelectDelete(pDup);
+  sqlite3Select(pParse, pDup, &dest);
+  sqlite3SelectDelete(db, pDup);
 }
 #endif /* !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER) */
 
+#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
+/*
+** Generate an expression tree to implement the WHERE, ORDER BY,
+** and LIMIT/OFFSET portion of DELETE and UPDATE statements.
+**
+**     DELETE FROM table_wxyz WHERE a<5 ORDER BY a LIMIT 1;
+**                            \__________________________/
+**                               pLimitWhere (pInClause)
+*/
+SQLITE_PRIVATE Expr *sqlite3LimitWhere(
+  Parse *pParse,               /* The parser context */
+  SrcList *pSrc,               /* the FROM clause -- which tables to scan */
+  Expr *pWhere,                /* The WHERE clause.  May be null */
+  ExprList *pOrderBy,          /* The ORDER BY clause.  May be null */
+  Expr *pLimit,                /* The LIMIT clause.  May be null */
+  Expr *pOffset,               /* The OFFSET clause.  May be null */
+  char *zStmtType              /* Either DELETE or UPDATE.  For error messages. */
+){
+  Expr *pWhereRowid = NULL;    /* WHERE rowid .. */
+  Expr *pInClause = NULL;      /* WHERE rowid IN ( select ) */
+  Expr *pSelectRowid = NULL;   /* SELECT rowid ... */
+  ExprList *pEList = NULL;     /* Expression list contaning only pSelectRowid */
+  SrcList *pSelectSrc = NULL;  /* SELECT rowid FROM x ... (dup of pSrc) */
+  Select *pSelect = NULL;      /* Complete SELECT tree */
+
+  /* Check that there isn't an ORDER BY without a LIMIT clause.
+  */
+  if( pOrderBy && (pLimit == 0) ) {
+    sqlite3ErrorMsg(pParse, "ORDER BY without LIMIT on %s", zStmtType);
+    pParse->parseError = 1;
+    goto limit_where_cleanup_2;
+  }
+
+  /* We only need to generate a select expression if there
+  ** is a limit/offset term to enforce.
+  */
+  if( pLimit == 0 ) {
+    /* if pLimit is null, pOffset will always be null as well. */
+    assert( pOffset == 0 );
+    return pWhere;
+  }
+
+  /* Generate a select expression tree to enforce the limit/offset 
+  ** term for the DELETE or UPDATE statement.  For example:
+  **   DELETE FROM table_a WHERE col1=1 ORDER BY col2 LIMIT 1 OFFSET 1
+  ** becomes:
+  **   DELETE FROM table_a WHERE rowid IN ( 
+  **     SELECT rowid FROM table_a WHERE col1=1 ORDER BY col2 LIMIT 1 OFFSET 1
+  **   );
+  */
+
+  pSelectRowid = sqlite3Expr(pParse->db, TK_ROW, 0, 0, 0);
+  if( pSelectRowid == 0 ) goto limit_where_cleanup_2;
+  pEList = sqlite3ExprListAppend(pParse, 0, pSelectRowid, 0);
+  if( pEList == 0 ) goto limit_where_cleanup_2;
+
+  /* duplicate the FROM clause as it is needed by both the DELETE/UPDATE tree
+  ** and the SELECT subtree. */
+  pSelectSrc = sqlite3SrcListDup(pParse->db, pSrc);
+  if( pSelectSrc == 0 ) {
+    sqlite3ExprListDelete(pParse->db, pEList);
+    goto limit_where_cleanup_2;
+  }
+
+  /* generate the SELECT expression tree. */
+  pSelect = sqlite3SelectNew(pParse,pEList,pSelectSrc,pWhere,0,0,pOrderBy,0,pLimit,pOffset);
+  if( pSelect == 0 ) return 0;
+
+  /* now generate the new WHERE rowid IN clause for the DELETE/UDPATE */
+  pWhereRowid = sqlite3Expr(pParse->db, TK_ROW, 0, 0, 0);
+  if( pWhereRowid == 0 ) goto limit_where_cleanup_1;
+  pInClause = sqlite3PExpr(pParse, TK_IN, pWhereRowid, 0, 0);
+  if( pInClause == 0 ) goto limit_where_cleanup_1;
+
+  pInClause->pSelect = pSelect;
+  sqlite3ExprSetHeight(pParse, pInClause);
+  return pInClause;
+
+  /* something went wrong. clean up anything allocated. */
+limit_where_cleanup_1:
+  sqlite3SelectDelete(pParse->db, pSelect);
+  return 0;
+
+limit_where_cleanup_2:
+  sqlite3ExprDelete(pParse->db, pWhere);
+  sqlite3ExprListDelete(pParse->db, pOrderBy);
+  sqlite3ExprDelete(pParse->db, pLimit);
+  sqlite3ExprDelete(pParse->db, pOffset);
+  return 0;
+}
+#endif /* defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY) */
 
 /*
 ** Generate code for a DELETE FROM statement.
@@ -54837,16 +62155,18 @@ SQLITE_PRIVATE void sqlite3DeleteFrom(
   /* If we are trying to delete from a view, realize that view into
   ** a ephemeral table.
   */
+#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
   if( isView ){
-    sqlite3MaterializeView(pParse, pTab->pSelect, pWhere, old_col_mask, iCur);
+    sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
   }
+#endif
 
   /* Resolve the column names in the WHERE clause.
   */
   memset(&sNC, 0, sizeof(sNC));
   sNC.pParse = pParse;
   sNC.pSrcList = pTabList;
-  if( sqlite3ExprResolveNames(&sNC, pWhere) ){
+  if( sqlite3ResolveExprNames(&sNC, pWhere) ){
     goto delete_from_cleanup;
   }
 
@@ -54858,6 +62178,7 @@ SQLITE_PRIVATE void sqlite3DeleteFrom(
     sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt);
   }
 
+#ifndef SQLITE_OMIT_TRUNCATE_OPTIMIZATION
   /* Special case: A DELETE without a WHERE clause deletes everything.
   ** It is easier just to erase the whole table.  Note, however, that
   ** this means that the row change count will be incorrect.
@@ -54885,11 +62206,12 @@ SQLITE_PRIVATE void sqlite3DeleteFrom(
         sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
       }
     }
-  } 
+  }else
+#endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */
   /* The usual case: There is a WHERE clause so we have to scan through
   ** the table and pick which records to delete.
   */
-  else{
+  {
     int iRowid = ++pParse->nMem;    /* Used for storing rowid values. */
 
     /* Begin the database scan
@@ -54912,8 +62234,8 @@ SQLITE_PRIVATE void sqlite3DeleteFrom(
     /* Open the pseudo-table used to store OLD if there are triggers.
     */
     if( triggers_exist ){
+      sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
       sqlite3VdbeAddOp1(v, OP_OpenPseudo, oldIdx);
-      sqlite3VdbeAddOp2(v, OP_SetNumColumns, oldIdx, pTab->nCol);
     }
 
     /* Delete every item whose key was written to the list during the
@@ -54963,7 +62285,7 @@ SQLITE_PRIVATE void sqlite3DeleteFrom(
 #ifndef SQLITE_OMIT_VIRTUALTABLE
       if( IsVirtual(pTab) ){
         const char *pVtab = (const char *)pTab->pVtab;
-        pParse->pVirtualLock = pTab;
+        sqlite3VtabMakeWritable(pParse, pTab);
         sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, pVtab, P4_VTAB);
       }else
 #endif
@@ -55007,8 +62329,8 @@ SQLITE_PRIVATE void sqlite3DeleteFrom(
 
 delete_from_cleanup:
   sqlite3AuthContextPop(&sContext);
-  sqlite3SrcListDelete(pTabList);
-  sqlite3ExprDelete(pWhere);
+  sqlite3SrcListDelete(db, pTabList);
+  sqlite3ExprDelete(db, pWhere);
   return;
 }
 
@@ -55078,18 +62400,16 @@ SQLITE_PRIVATE void sqlite3GenerateRowIndexDelete(
   Index *pIdx;
   int r1;
 
-  r1 = sqlite3GetTempReg(pParse);
   for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
     if( aRegIdx!=0 && aRegIdx[i-1]==0 ) continue;
-    sqlite3GenerateIndexKey(pParse, pIdx, iCur, r1);
-    sqlite3VdbeAddOp2(pParse->pVdbe, OP_IdxDelete, iCur+i, r1);
+    r1 = sqlite3GenerateIndexKey(pParse, pIdx, iCur, 0, 0);
+    sqlite3VdbeAddOp3(pParse->pVdbe, OP_IdxDelete, iCur+i, r1,pIdx->nColumn+1);
   }
-  sqlite3ReleaseTempReg(pParse, r1);
 }
 
 /*
-** Generate code that will assemble an index key and put it on the top
-** of the tack.  The key with be for index pIdx which is an index on pTab.
+** Generate code that will assemble an index key and put it in register
+** regOut.  The key with be for index pIdx which is an index on pTab.
 ** iCur is the index of a cursor open on the pTab table and pointing to
 ** the entry that needs indexing.
 **
@@ -55102,7 +62422,8 @@ SQLITE_PRIVATE int sqlite3GenerateIndexKey(
   Parse *pParse,     /* Parsing context */
   Index *pIdx,       /* The index for which to generate a key */
   int iCur,          /* Cursor number for the pIdx->pTable table */
-  int regOut         /* Write the new index key to this register */
+  int regOut,        /* Write the new index key to this register */
+  int doMakeRec      /* Run the OP_MakeRecord instruction if true */
 ){
   Vdbe *v = pParse->pVdbe;
   int j;
@@ -55122,12 +62443,20 @@ SQLITE_PRIVATE int sqlite3GenerateIndexKey(
       sqlite3ColumnDefault(v, pTab, idx);
     }
   }
-  sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol+1, regOut);
-  sqlite3IndexAffinityStr(v, pIdx);
+  if( doMakeRec ){
+    sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol+1, regOut);
+    sqlite3IndexAffinityStr(v, pIdx);
+    sqlite3ExprCacheAffinityChange(pParse, regBase, nCol+1);
+  }
   sqlite3ReleaseTempRange(pParse, regBase, nCol+1);
   return regBase;
 }
 
+/* Make sure "isView" gets undefined in case this file becomes part of
+** the amalgamation - so that subsequent files do not see isView as a
+** macro. */
+#undef isView
+
 /************** End of delete.c **********************************************/
 /************** Begin file func.c ********************************************/
 /*
@@ -55148,10 +62477,9 @@ SQLITE_PRIVATE int sqlite3GenerateIndexKey(
 ** sqliteRegisterBuildinFunctions() found at the bottom of the file.
 ** All other code has file scope.
 **
-** $Id: func.c,v 1.186 2008/03/06 09:58:50 mlcreech Exp $
+** $Id: func.c,v 1.203 2008/09/03 17:11:16 drh Exp $
 */
 
-
 /*
 ** Return the collating function associated with a function.
 */
@@ -55315,7 +62643,7 @@ static void substrFunc(
   if( argc==3 ){
     p2 = sqlite3_value_int(argv[2]);
   }else{
-    p2 = SQLITE_MAX_LENGTH;
+    p2 = sqlite3_context_db_handle(context)->aLimit[SQLITE_LIMIT_LENGTH];
   }
   if( p1<0 ){
     p1 += len;
@@ -55370,10 +62698,16 @@ static void roundFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
 ** allocation fails, call sqlite3_result_error_nomem() to notify
 ** the database handle that malloc() has failed.
 */
-static void *contextMalloc(sqlite3_context *context, int nByte){
-  char *z = sqlite3_malloc(nByte);
-  if( !z && nByte>0 ){
-    sqlite3_result_error_nomem(context);
+static void *contextMalloc(sqlite3_context *context, i64 nByte){
+  char *z;
+  if( nByte>sqlite3_context_db_handle(context)->aLimit[SQLITE_LIMIT_LENGTH] ){
+    sqlite3_result_error_toobig(context);
+    z = 0;
+  }else{
+    z = sqlite3Malloc(nByte);
+    if( !z && nByte>0 ){
+      sqlite3_result_error_nomem(context);
+    }
   }
   return z;
 }
@@ -55391,7 +62725,7 @@ static void upperFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
   /* Verify that the call to _bytes() does not invalidate the _text() pointer */
   assert( z2==(char*)sqlite3_value_text(argv[0]) );
   if( z2 ){
-    z1 = contextMalloc(context, n+1);
+    z1 = contextMalloc(context, ((i64)n)+1);
     if( z1 ){
       memcpy(z1, z2, n+1);
       for(i=0; z1[i]; i++){
@@ -55411,7 +62745,7 @@ static void lowerFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
   /* Verify that the call to _bytes() does not invalidate the _text() pointer */
   assert( z2==(char*)sqlite3_value_text(argv[0]) );
   if( z2 ){
-    z1 = contextMalloc(context, n+1);
+    z1 = contextMalloc(context, ((i64)n)+1);
     if( z1 ){
       memcpy(z1, z2, n+1);
       for(i=0; z1[i]; i++){
@@ -55450,7 +62784,7 @@ static void randomFunc(
   sqlite3_value **argv
 ){
   sqlite_int64 r;
-  sqlite3Randomness(sizeof(r), &r);
+  sqlite3_randomness(sizeof(r), &r);
   if( (r<<1)==0 ) r = 0;  /* Prevent 0x8000.... as the result so that we */
                           /* can always do abs() of the result */
   sqlite3_result_int64(context, r);
@@ -55472,13 +62806,9 @@ static void randomBlob(
   if( n<1 ){
     n = 1;
   }
-  if( n>SQLITE_MAX_LENGTH ){
-    sqlite3_result_error_toobig(context);
-    return;
-  }
   p = contextMalloc(context, n);
   if( p ){
-    sqlite3Randomness(n, p);
+    sqlite3_randomness(n, p);
     sqlite3_result_blob(context, (char*)p, n, sqlite3_free);
   }
 }
@@ -55492,7 +62822,7 @@ static void last_insert_rowid(
   int arg, 
   sqlite3_value **argv
 ){
-  sqlite3 *db = sqlite3_user_data(context);
+  sqlite3 *db = sqlite3_context_db_handle(context);
   sqlite3_result_int64(context, sqlite3_last_insert_rowid(db));
 }
 
@@ -55505,7 +62835,7 @@ static void changes(
   int arg,
   sqlite3_value **argv
 ){
-  sqlite3 *db = sqlite3_user_data(context);
+  sqlite3 *db = sqlite3_context_db_handle(context);
   sqlite3_result_int(context, sqlite3_changes(db));
 }
 
@@ -55518,7 +62848,7 @@ static void total_changes(
   int arg,
   sqlite3_value **argv
 ){
-  sqlite3 *db = sqlite3_user_data(context);
+  sqlite3 *db = sqlite3_context_db_handle(context);
   sqlite3_result_int(context, sqlite3_total_changes(db));
 }
 
@@ -55718,6 +63048,7 @@ static void likeFunc(
 ){
   const unsigned char *zA, *zB;
   int escape = 0;
+  sqlite3 *db = sqlite3_context_db_handle(context);
 
   zB = sqlite3_value_text(argv[0]);
   zA = sqlite3_value_text(argv[1]);
@@ -55725,7 +63056,8 @@ static void likeFunc(
   /* Limit the length of the LIKE or GLOB pattern to avoid problems
   ** of deep recursion and N*N behavior in patternCompare().
   */
-  if( sqlite3_value_bytes(argv[0])>SQLITE_MAX_LIKE_PATTERN_LENGTH ){
+  if( sqlite3_value_bytes(argv[0]) >
+        db->aLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH] ){
     sqlite3_result_error(context, "LIKE or GLOB pattern too complex", -1);
     return;
   }
@@ -55817,12 +63149,7 @@ static void quoteFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
       char const *zBlob = sqlite3_value_blob(argv[0]);
       int nBlob = sqlite3_value_bytes(argv[0]);
       assert( zBlob==sqlite3_value_blob(argv[0]) ); /* No encoding change */
-
-      if( 2*nBlob+4>SQLITE_MAX_LENGTH ){
-        sqlite3_result_error_toobig(context);
-        return;
-      }
-      zText = (char *)contextMalloc(context, (2*nBlob)+4); 
+      zText = (char *)contextMalloc(context, (2*(i64)nBlob)+4); 
       if( zText ){
         int i;
         for(i=0; iSQLITE_MAX_LENGTH ){
-        sqlite3_result_error_toobig(context);
-        return;
-      }
-      z = contextMalloc(context, i+n+3);
+      z = contextMalloc(context, ((i64)i)+((i64)n)+3);
       if( z ){
         z[0] = '\'';
         for(i=0, j=1; zArg[i]; i++){
@@ -55882,12 +63205,8 @@ static void hexFunc(
   assert( argc==1 );
   pBlob = sqlite3_value_blob(argv[0]);
   n = sqlite3_value_bytes(argv[0]);
-  if( n*2+1>SQLITE_MAX_LENGTH ){
-    sqlite3_result_error_toobig(context);
-    return;
-  }
   assert( pBlob==sqlite3_value_blob(argv[0]) );  /* No encoding change */
-  z = zHex = contextMalloc(context, n*2 + 1);
+  z = zHex = contextMalloc(context, ((i64)n)*2 + 1);
   if( zHex ){
     for(i=0; i=SQLITE_MAX_LENGTH ){
+      if( nOut>=db->aLimit[SQLITE_LIMIT_LENGTH] ){
         sqlite3_result_error_toobig(context);
-        sqlite3_free(zOut);
+        sqlite3DbFree(db, zOut);
         return;
       }
       zOld = zOut;
       zOut = sqlite3_realloc(zOut, (int)nOut);
       if( zOut==0 ){
         sqlite3_result_error_nomem(context);
-        sqlite3_free(zOld);
+        sqlite3DbFree(db, zOld);
         return;
       }
       memcpy(&zOut[j], zRep, nRep);
@@ -56002,7 +63322,7 @@ static void trimFunc(
   const unsigned char *zIn;         /* Input string */
   const unsigned char *zCharSet;    /* Set of characters to trim */
   int nIn;                          /* Number of bytes in input */
-  sqlite3_intptr_t flags;           /* 1: trimleft  2: trimright  3: trim */
+  int flags;                        /* 1: trimleft  2: trimright  3: trim */
   int i;                            /* Loop counter */
   unsigned char *aLen;              /* Length of each character in zCharSet */
   unsigned char **azChar;           /* Individual characters in zCharSet */
@@ -56017,7 +63337,7 @@ static void trimFunc(
   assert( zIn==sqlite3_value_text(argv[0]) );
   if( argc==1 ){
     static const unsigned char lenOne[] = { 1 };
-    static const unsigned char *azOne[] = { (u8*)" " };
+    static unsigned char * const azOne[] = { (u8*)" " };
     nChar = 1;
     aLen = (u8*)lenOne;
     azChar = (unsigned char **)azOne;
@@ -56030,7 +63350,7 @@ static void trimFunc(
       SQLITE_SKIP_UTF8(z);
     }
     if( nChar>0 ){
-      azChar = contextMalloc(context, nChar*(sizeof(char*)+1));
+      azChar = contextMalloc(context, ((i64)nChar)*(sizeof(char*)+1));
       if( azChar==0 ){
         return;
       }
@@ -56043,7 +63363,7 @@ static void trimFunc(
     }
   }
   if( nChar>0 ){
-    flags = (sqlite3_intptr_t)sqlite3_user_data(context);
+    flags = SQLITE_PTR_TO_INT(sqlite3_user_data(context));
     if( flags & 1 ){
       while( nIn>0 ){
         int len;
@@ -56074,6 +63394,7 @@ static void trimFunc(
   sqlite3_result_text(context, (char*)zIn, nIn, SQLITE_TRANSIENT);
 }
 
+
 #ifdef SQLITE_SOUNDEX
 /*
 ** Compute the soundex encoding of a word.
@@ -56132,7 +63453,7 @@ static void soundexFunc(
 static void loadExt(sqlite3_context *context, int argc, sqlite3_value **argv){
   const char *zFile = (const char *)sqlite3_value_text(argv[0]);
   const char *zProc;
-  sqlite3 *db = sqlite3_user_data(context);
+  sqlite3 *db = sqlite3_context_db_handle(context);
   char *zErrMsg = 0;
 
   if( argc==2 ){
@@ -56147,166 +63468,6 @@ static void loadExt(sqlite3_context *context, int argc, sqlite3_value **argv){
 }
 #endif
 
-#ifdef SQLITE_TEST
-/*
-** This function generates a string of random characters.  Used for
-** generating test data.
-*/
-static void randStr(sqlite3_context *context, int argc, sqlite3_value **argv){
-  static const unsigned char zSrc[] = 
-     "abcdefghijklmnopqrstuvwxyz"
-     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-     "0123456789"
-     ".-!,:*^+=_|?/<> ";
-  int iMin, iMax, n, r, i;
-  unsigned char zBuf[1000];
-
-  /* It used to be possible to call randstr() with any number of arguments,
-  ** but now it is registered with SQLite as requiring exactly 2.
-  */
-  assert(argc==2);
-
-  iMin = sqlite3_value_int(argv[0]);
-  if( iMin<0 ) iMin = 0;
-  if( iMin>=sizeof(zBuf) ) iMin = sizeof(zBuf)-1;
-  iMax = sqlite3_value_int(argv[1]);
-  if( iMax=sizeof(zBuf) ) iMax = sizeof(zBuf)-1;
-  n = iMin;
-  if( iMax>iMin ){
-    sqlite3Randomness(sizeof(r), &r);
-    r &= 0x7fffffff;
-    n += r%(iMax + 1 - iMin);
-  }
-  assert( nuseMalloc = 1;
+    pAccum->mxAlloc = db->aLimit[SQLITE_LIMIT_LENGTH];
     if( pAccum->nChar ){
-      if( argc==2 ){
-        zSep = (char*)sqlite3_value_text(argv[1]);
-        nSep = sqlite3_value_bytes(argv[1]);
+      if( argc>1 ){
+        zSep = (char*)sqlite3_value_text(argv[argc-1]);
+        nSep = sqlite3_value_bytes(argv[argc-1]);
       }else{
         zSep = ",";
         nSep = 1;
       }
       sqlite3StrAccumAppend(pAccum, zSep, nSep);
     }
-    zVal = (char*)sqlite3_value_text(argv[0]);
-    nVal = sqlite3_value_bytes(argv[0]);
-    sqlite3StrAccumAppend(pAccum, zVal, nVal);
+    i = 0;
+    do{
+      zVal = (char*)sqlite3_value_text(argv[i]);
+      nVal = sqlite3_value_bytes(argv[i]);
+      sqlite3StrAccumAppend(pAccum, zVal, nVal);
+      i++;
+    }while( ineedCollSeq = 1;
-      }
-    }
-  }
 #ifndef SQLITE_OMIT_ALTERTABLE
   sqlite3AlterFunctions(db);
 #endif
 #ifndef SQLITE_OMIT_PARSER
   sqlite3AttachFunctions(db);
 #endif
-  for(i=0; ineedCollSeq = 1;
-      }
-    }
-  }
-  sqlite3RegisterDateTimeFunctions(db);
   if( !db->mallocFailed ){
     int rc = sqlite3_overload_function(db, "MATCH", 2);
     assert( rc==SQLITE_NOMEM || rc==SQLITE_OK );
@@ -56627,11 +63686,6 @@ SQLITE_PRIVATE void sqlite3RegisterBuiltinFunctions(sqlite3 *db){
 #ifdef SQLITE_SSE
   (void)sqlite3SseFunctions(db);
 #endif
-#ifdef SQLITE_CASE_SENSITIVE_LIKE
-  sqlite3RegisterLikeFunctions(db, 1);
-#else
-  sqlite3RegisterLikeFunctions(db, 0);
-#endif
 }
 
 /*
@@ -56699,6 +63753,93 @@ SQLITE_PRIVATE int sqlite3IsLikeFunction(sqlite3 *db, Expr *pExpr, int *pIsNocas
   return 1;
 }
 
+/*
+** All all of the FuncDef structures in the aBuiltinFunc[] array above
+** to the global function hash table.  This occurs at start-time (as
+** a consequence of calling sqlite3_initialize()).
+**
+** After this routine runs
+*/
+SQLITE_PRIVATE void sqlite3RegisterGlobalFunctions(void){
+  /*
+  ** The following array holds FuncDef structures for all of the functions
+  ** defined in this file.
+  **
+  ** The array cannot be constant since changes are made to the
+  ** FuncDef.pHash elements at start-time.  The elements of this array
+  ** are read-only after initialization is complete.
+  */
+  static SQLITE_WSD FuncDef aBuiltinFunc[] = {
+    FUNCTION(ltrim,              1, 1, 0, trimFunc         ),
+    FUNCTION(ltrim,              2, 1, 0, trimFunc         ),
+    FUNCTION(rtrim,              1, 2, 0, trimFunc         ),
+    FUNCTION(rtrim,              2, 2, 0, trimFunc         ),
+    FUNCTION(trim,               1, 3, 0, trimFunc         ),
+    FUNCTION(trim,               2, 3, 0, trimFunc         ),
+    FUNCTION(min,               -1, 0, 1, minmaxFunc       ),
+    FUNCTION(min,                0, 0, 1, 0                ),
+    AGGREGATE(min,               1, 0, 1, minmaxStep,      minMaxFinalize ),
+    FUNCTION(max,               -1, 1, 1, minmaxFunc       ),
+    FUNCTION(max,                0, 1, 1, 0                ),
+    AGGREGATE(max,               1, 1, 1, minmaxStep,      minMaxFinalize ),
+    FUNCTION(typeof,             1, 0, 0, typeofFunc       ),
+    FUNCTION(length,             1, 0, 0, lengthFunc       ),
+    FUNCTION(substr,             2, 0, 0, substrFunc       ),
+    FUNCTION(substr,             3, 0, 0, substrFunc       ),
+    FUNCTION(abs,                1, 0, 0, absFunc          ),
+    FUNCTION(round,              1, 0, 0, roundFunc        ),
+    FUNCTION(round,              2, 0, 0, roundFunc        ),
+    FUNCTION(upper,              1, 0, 0, upperFunc        ),
+    FUNCTION(lower,              1, 0, 0, lowerFunc        ),
+    FUNCTION(coalesce,           1, 0, 0, 0                ),
+    FUNCTION(coalesce,          -1, 0, 0, ifnullFunc       ),
+    FUNCTION(coalesce,           0, 0, 0, 0                ),
+    FUNCTION(hex,                1, 0, 0, hexFunc          ),
+    FUNCTION(ifnull,             2, 0, 1, ifnullFunc       ),
+    FUNCTION(random,            -1, 0, 0, randomFunc       ),
+    FUNCTION(randomblob,         1, 0, 0, randomBlob       ),
+    FUNCTION(nullif,             2, 0, 1, nullifFunc       ),
+    FUNCTION(sqlite_version,     0, 0, 0, versionFunc      ),
+    FUNCTION(quote,              1, 0, 0, quoteFunc        ),
+    FUNCTION(last_insert_rowid,  0, 0, 0, last_insert_rowid),
+    FUNCTION(changes,            0, 0, 0, changes          ),
+    FUNCTION(total_changes,      0, 0, 0, total_changes    ),
+    FUNCTION(replace,            3, 0, 0, replaceFunc      ),
+    FUNCTION(zeroblob,           1, 0, 0, zeroblobFunc     ),
+  #ifdef SQLITE_SOUNDEX
+    FUNCTION(soundex,            1, 0, 0, soundexFunc      ),
+  #endif
+  #ifndef SQLITE_OMIT_LOAD_EXTENSION
+    FUNCTION(load_extension,     1, 0, 0, loadExt          ),
+    FUNCTION(load_extension,     2, 0, 0, loadExt          ),
+  #endif
+    AGGREGATE(sum,               1, 0, 0, sumStep,         sumFinalize    ),
+    AGGREGATE(total,             1, 0, 0, sumStep,         totalFinalize    ),
+    AGGREGATE(avg,               1, 0, 0, sumStep,         avgFinalize    ),
+    AGGREGATE(count,             0, 0, 0, countStep,       countFinalize  ),
+    AGGREGATE(count,             1, 0, 0, countStep,       countFinalize  ),
+    AGGREGATE(group_concat,     -1, 0, 0, groupConcatStep, groupConcatFinalize),
+  
+    LIKEFUNC(glob, 2, &globInfo, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE),
+  #ifdef SQLITE_CASE_SENSITIVE_LIKE
+    LIKEFUNC(like, 2, &likeInfoAlt, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE),
+    LIKEFUNC(like, 3, &likeInfoAlt, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE),
+  #else
+    LIKEFUNC(like, 2, &likeInfoNorm, SQLITE_FUNC_LIKE),
+    LIKEFUNC(like, 3, &likeInfoNorm, SQLITE_FUNC_LIKE),
+  #endif
+  };
+
+  int i;
+  FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
+  FuncDef *aFunc = (FuncDef*)&GLOBAL(FuncDef, aBuiltinFunc);
+
+  for(i=0; ipTable;
     sqlite3 *db = sqlite3VdbeDb(v);
-    pIdx->zColAff = (char *)sqlite3DbMallocZero(db, pIdx->nColumn+2);
+    pIdx->zColAff = (char *)sqlite3Malloc(pIdx->nColumn+2);
     if( !pIdx->zColAff ){
+      db->mallocFailed = 1;
       return;
     }
     for(n=0; nnColumn; n++){
@@ -56788,8 +63930,9 @@ SQLITE_PRIVATE void sqlite3TableAffinityStr(Vdbe *v, Table *pTab){
     int i;
     sqlite3 *db = sqlite3VdbeDb(v);
 
-    zColAff = (char *)sqlite3DbMallocZero(db, pTab->nCol+1);
+    zColAff = (char *)sqlite3Malloc(pTab->nCol+1);
     if( !zColAff ){
+      db->mallocFailed = 1;
       return;
     }
 
@@ -56865,7 +64008,7 @@ static int autoIncBegin(
   Table *pTab         /* The table we are writing to */
 ){
   int memId = 0;      /* Register holding maximum rowid */
-  if( pTab->autoInc ){
+  if( pTab->tabFlags & TF_Autoincrement ){
     Vdbe *v = pParse->pVdbe;
     Db *pDb = &pParse->db->aDb[iDb];
     int iCur = pParse->nTab;
@@ -56877,14 +64020,15 @@ static int autoIncBegin(
     sqlite3OpenTable(pParse, iCur, iDb, pDb->pSchema->pSeqTab, OP_OpenRead);
     addr = sqlite3VdbeCurrentAddr(v);
     sqlite3VdbeAddOp4(v, OP_String8, 0, memId-1, 0, pTab->zName, 0);
-    sqlite3VdbeAddOp2(v, OP_Rewind, iCur, addr+8);
+    sqlite3VdbeAddOp2(v, OP_Rewind, iCur, addr+9);
     sqlite3VdbeAddOp3(v, OP_Column, iCur, 0, memId);
     sqlite3VdbeAddOp3(v, OP_Ne, memId-1, addr+7, memId);
     sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
     sqlite3VdbeAddOp2(v, OP_Rowid, iCur, memId+1);
     sqlite3VdbeAddOp3(v, OP_Column, iCur, 1, memId);
-    sqlite3VdbeAddOp2(v, OP_Goto, 0, addr+8);
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, addr+9);
     sqlite3VdbeAddOp2(v, OP_Next, iCur, addr+2);
+    sqlite3VdbeAddOp2(v, OP_Integer, 0, memId);
     sqlite3VdbeAddOp2(v, OP_Close, iCur, 0);
   }
   return memId;
@@ -56915,7 +64059,7 @@ static void autoIncEnd(
   Table *pTab,       /* Table we are inserting into */
   int memId          /* Memory cell holding the maximum rowid */
 ){
-  if( pTab->autoInc ){
+  if( pTab->tabFlags & TF_Autoincrement ){
     int iCur = pParse->nTab;
     Vdbe *v = pParse->pVdbe;
     Db *pDb = &pParse->db->aDb[iDb];
@@ -56970,7 +64114,8 @@ static int xferOptimization(
 **
 ** The code generated follows one of four templates.  For a simple
 ** select with data coming from a VALUES clause, the code executes
-** once straight down through.  The template looks like this:
+** once straight down through.  Pseudo-code follows (we call this
+** the "1st template"):
 **
 **         open write cursor to 
       and its indices
 **         puts VALUES clause expressions onto the stack
@@ -56988,7 +64133,7 @@ static int xferOptimization(
 ** schemas, including all the same indices, then a special optimization
 ** is invoked that copies raw records from  over to .
 ** See the xferOptimization() function for the implementation of this
-** template.  This is the second template.
+** template.  This is the 2nd template.
 **
 **         open a write cursor to 
      
 **         open read cursor on 
@@ -57001,45 +64146,58 @@ static int xferOptimization(
 **           close cursors
 **         end foreach
 **
-** The third template is for when the second template does not apply
+** The 3rd template is for when the second template does not apply
 ** and the SELECT clause does not read from 
       at any time.
 ** The generated code follows this template:
 **
+**         EOF <- 0
+**         X <- A
 **         goto B
 **      A: setup for the SELECT
 **         loop over the rows in the SELECT
-**           gosub C
+**           load values into registers R..R+n
+**           yield X
 **         end loop
 **         cleanup after the SELECT
-**         goto D
-**      B: open write cursor to 
       and its indices
+**         EOF <- 1
+**         yield X
 **         goto A
-**      C: insert the select result into 
      
-**         return
+**      B: open write cursor to 
       and its indices
+**      C: yield X
+**         if EOF goto D
+**         insert the select result into 
       from R..R+n
+**         goto C
 **      D: cleanup
 **
-** The fourth template is used if the insert statement takes its
+** The 4th template is used if the insert statement takes its
 ** values from a SELECT but the data is being inserted into a table
 ** that is also read as part of the SELECT.  In the third form,
 ** we have to use a intermediate table to store the results of
 ** the select.  The template is like this:
 **
+**         EOF <- 0
+**         X <- A
 **         goto B
 **      A: setup for the SELECT
 **         loop over the tables in the SELECT
-**           gosub C
+**           load value into register R..R+n
+**           yield X
 **         end loop
 **         cleanup after the SELECT
-**         goto D
-**      C: insert the select result into the intermediate table
-**         return
-**      B: open a cursor to an intermediate table
-**         goto A
-**      D: open write cursor to 
       and its indices
-**         loop over the intermediate table
+**         EOF <- 1
+**         yield X
+**         halt-error
+**      B: open temp table
+**      L: yield X
+**         if EOF goto M
+**         insert row from R..R+n into temp table
+**         goto L
+**      M: open write cursor to 
       and its indices
+**         rewind temp table
+**      C: loop over rows of intermediate table
 **           transfer values form intermediate table into 
      
-**         end the loop
-**         cleanup
+**         end loop
+**      D: cleanup
 */
 SQLITE_PRIVATE void sqlite3Insert(
   Parse *pParse,        /* Parser context */
@@ -57063,10 +64221,10 @@ SQLITE_PRIVATE void sqlite3Insert(
   int endOfLoop;        /* Label for the end of the insertion loop */
   int useTempTable = 0; /* Store SELECT results in intermediate table */
   int srcTab = 0;       /* Data comes from this temporary cursor if >=0 */
-  int iCont=0,iBreak=0; /* Beginning and end of the loop over srcTab */
-  int iSelectLoop = 0;  /* Address of code that implements the SELECT */
-  int iCleanup = 0;     /* Address of the cleanup code */
-  int iInsertBlock = 0; /* Address of the subroutine used to insert data */
+  int addrInsTop = 0;   /* Jump to label "D" */
+  int addrCont = 0;     /* Top of insert loop. Label "C" in templates 3 and 4 */
+  int addrSelect = 0;   /* Address of coroutine that implements the SELECT */
+  SelectDest dest;      /* Destination for SELECT on rhs of INSERT */
   int newIdx = -1;      /* Cursor for the NEW pseudo-table */
   int iDb;              /* Index of database holding TABLE */
   Db *pDb;              /* The database containing table being inserted into */
@@ -57080,6 +64238,7 @@ SQLITE_PRIVATE void sqlite3Insert(
   int regRowid;         /* registers holding insert rowid */
   int regData;          /* register holding first column to insert */
   int regRecord;        /* Holds the assemblied row record */
+  int regEof;           /* Register recording end of SELECT data */
   int *aRegIdx = 0;     /* One register allocated to each index */
 
 
@@ -57161,6 +64320,8 @@ SQLITE_PRIVATE void sqlite3Insert(
   **
   ** Then special optimizations can be applied that make the transfer
   ** very fast and which reduce fragmentation of indices.
+  **
+  ** This is the 2nd template.
   */
   if( pColumn==0 && xferOptimization(pParse, pTab, pSelect, onError, iDb) ){
     assert( !triggers_exist );
@@ -57175,76 +64336,103 @@ SQLITE_PRIVATE void sqlite3Insert(
   regAutoinc = autoIncBegin(pParse, iDb, pTab);
 
   /* Figure out how many columns of data are supplied.  If the data
-  ** is coming from a SELECT statement, then this step also generates
-  ** all the code to implement the SELECT statement and invoke a subroutine
-  ** to process each row of the result. (Template 2.) If the SELECT
-  ** statement uses the the table that is being inserted into, then the
-  ** subroutine is also coded here.  That subroutine stores the SELECT
-  ** results in a temporary table. (Template 3.)
+  ** is coming from a SELECT statement, then generate a co-routine that
+  ** produces a single row of the SELECT on each invocation.  The
+  ** co-routine is the common header to the 3rd and 4th templates.
   */
   if( pSelect ){
     /* Data is coming from a SELECT.  Generate code to implement that SELECT
+    ** as a co-routine.  The code is common to both the 3rd and 4th
+    ** templates:
+    **
+    **         EOF <- 0
+    **         X <- A
+    **         goto B
+    **      A: setup for the SELECT
+    **         loop over the tables in the SELECT
+    **           load value into register R..R+n
+    **           yield X
+    **         end loop
+    **         cleanup after the SELECT
+    **         EOF <- 1
+    **         yield X
+    **         halt-error
+    **
+    ** On each invocation of the co-routine, it puts a single row of the
+    ** SELECT result into registers dest.iMem...dest.iMem+dest.nMem-1.
+    ** (These output registers are allocated by sqlite3Select().)  When
+    ** the SELECT completes, it sets the EOF flag stored in regEof.
     */
-    SelectDest dest;
-    int rc, iInitCode;
+    int rc, j1;
 
-    iInitCode = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
-    iSelectLoop = sqlite3VdbeCurrentAddr(v);
-    iInsertBlock = sqlite3VdbeMakeLabel(v);
-    sqlite3SelectDestInit(&dest, SRT_Subroutine, iInsertBlock);
+    regEof = ++pParse->nMem;
+    sqlite3VdbeAddOp2(v, OP_Integer, 0, regEof);      /* EOF <- 0 */
+    VdbeComment((v, "SELECT eof flag"));
+    sqlite3SelectDestInit(&dest, SRT_Coroutine, ++pParse->nMem);
+    addrSelect = sqlite3VdbeCurrentAddr(v)+2;
+    sqlite3VdbeAddOp2(v, OP_Integer, addrSelect-1, dest.iParm);
+    j1 = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
+    VdbeComment((v, "Jump over SELECT coroutine"));
 
     /* Resolve the expressions in the SELECT statement and execute it. */
-    rc = sqlite3Select(pParse, pSelect, &dest, 0, 0, 0, 0);
+    rc = sqlite3Select(pParse, pSelect, &dest);
     if( rc || pParse->nErr || db->mallocFailed ){
       goto insert_cleanup;
     }
+    sqlite3VdbeAddOp2(v, OP_Integer, 1, regEof);         /* EOF <- 1 */
+    sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);   /* yield X */
+    sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_INTERNAL, OE_Abort);
+    VdbeComment((v, "End of SELECT coroutine"));
+    sqlite3VdbeJumpHere(v, j1);                          /* label B: */
 
     regFromSelect = dest.iMem;
-    iCleanup = sqlite3VdbeMakeLabel(v);
-    sqlite3VdbeAddOp2(v, OP_Goto, 0, iCleanup);
     assert( pSelect->pEList );
     nColumn = pSelect->pEList->nExpr;
+    assert( dest.nMem==nColumn );
 
     /* Set useTempTable to TRUE if the result of the SELECT statement
-    ** should be written into a temporary table.  Set to FALSE if each
-    ** row of the SELECT can be written directly into the result table.
+    ** should be written into a temporary table (template 4).  Set to
+    ** FALSE if each* row of the SELECT can be written directly into
+    ** the destination table (template 3).
     **
     ** A temp table must be used if the table being updated is also one
     ** of the tables being read by the SELECT statement.  Also use a 
     ** temp table in the case of row triggers.
     */
-    if( triggers_exist || readsTable(v, iSelectLoop, iDb, pTab) ){
+    if( triggers_exist || readsTable(v, addrSelect, iDb, pTab) ){
       useTempTable = 1;
     }
 
     if( useTempTable ){
-      /* Generate the subroutine that SELECT calls to process each row of
-      ** the result.  Store the result in a temporary table
+      /* Invoke the coroutine to extract information from the SELECT
+      ** and add it to a transient table srcTab.  The code generated
+      ** here is from the 4th template:
+      **
+      **      B: open temp table
+      **      L: yield X
+      **         if EOF goto M
+      **         insert row from R..R+n into temp table
+      **         goto L
+      **      M: ...
       */
-      int regRec, regRowid;
+      int regRec;      /* Register to hold packed record */
+      int regRowid;    /* Register to hold temp table ROWID */
+      int addrTop;     /* Label "L" */
+      int addrIf;      /* Address of jump to M */
 
       srcTab = pParse->nTab++;
       regRec = sqlite3GetTempReg(pParse);
       regRowid = sqlite3GetTempReg(pParse);
-      sqlite3VdbeResolveLabel(v, iInsertBlock);
+      sqlite3VdbeAddOp2(v, OP_OpenEphemeral, srcTab, nColumn);
+      addrTop = sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);
+      addrIf = sqlite3VdbeAddOp1(v, OP_If, regEof);
       sqlite3VdbeAddOp3(v, OP_MakeRecord, regFromSelect, nColumn, regRec);
       sqlite3VdbeAddOp2(v, OP_NewRowid, srcTab, regRowid);
       sqlite3VdbeAddOp3(v, OP_Insert, srcTab, regRec, regRowid);
-      sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
+      sqlite3VdbeAddOp2(v, OP_Goto, 0, addrTop);
+      sqlite3VdbeJumpHere(v, addrIf);
       sqlite3ReleaseTempReg(pParse, regRec);
       sqlite3ReleaseTempReg(pParse, regRowid);
-
-      /* The following code runs first because the GOTO at the very top
-      ** of the program jumps to it.  Create the temporary table, then jump
-      ** back up and execute the SELECT code above.
-      */
-      sqlite3VdbeJumpHere(v, iInitCode);
-      sqlite3VdbeAddOp2(v, OP_OpenEphemeral, srcTab, 0);
-      sqlite3VdbeAddOp2(v, OP_SetNumColumns, srcTab, nColumn);
-      sqlite3VdbeAddOp2(v, OP_Goto, 0, iSelectLoop);
-      sqlite3VdbeResolveLabel(v, iCleanup);
-    }else{
-      sqlite3VdbeJumpHere(v, iInitCode);
     }
   }else{
     /* This is the case if the data for the INSERT is coming from a VALUES
@@ -57257,7 +64445,7 @@ SQLITE_PRIVATE void sqlite3Insert(
     assert( useTempTable==0 );
     nColumn = pList ? pList->nExpr : 0;
     for(i=0; ia[i].pExpr) ){
+      if( sqlite3ResolveExprNames(&sNC, pList->a[i].pExpr) ){
         goto insert_cleanup;
       }
     }
@@ -57331,8 +64519,8 @@ SQLITE_PRIVATE void sqlite3Insert(
   /* Open the temp table for FOR EACH ROW triggers
   */
   if( triggers_exist ){
+    sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
     sqlite3VdbeAddOp2(v, OP_OpenPseudo, newIdx, 0);
-    sqlite3VdbeAddOp2(v, OP_SetNumColumns, newIdx, pTab->nCol);
   }
     
   /* Initialize the count of rows to be inserted
@@ -57349,7 +64537,7 @@ SQLITE_PRIVATE void sqlite3Insert(
 
     baseCur = pParse->nTab;
     nIdx = sqlite3OpenTableAndIndices(pParse, pTab, baseCur, OP_OpenWrite);
-    aRegIdx = sqlite3DbMallocZero(db, sizeof(int)*(nIdx+1));
+    aRegIdx = sqlite3DbMallocRaw(db, sizeof(int)*(nIdx+1));
     if( aRegIdx==0 ){
       goto insert_cleanup;
     }
@@ -57358,18 +64546,31 @@ SQLITE_PRIVATE void sqlite3Insert(
     }
   }
 
-  /* If the data source is a temporary table, then we have to create
-  ** a loop because there might be multiple rows of data.  If the data
-  ** source is a subroutine call from the SELECT statement, then we need
-  ** to launch the SELECT statement processing.
-  */
+  /* This is the top of the main insertion loop */
   if( useTempTable ){
-    iBreak = sqlite3VdbeMakeLabel(v);
-    sqlite3VdbeAddOp2(v, OP_Rewind, srcTab, iBreak);
-    iCont = sqlite3VdbeCurrentAddr(v);
+    /* This block codes the top of loop only.  The complete loop is the
+    ** following pseudocode (template 4):
+    **
+    **         rewind temp table
+    **      C: loop over rows of intermediate table
+    **           transfer values form intermediate table into 
      
+    **         end loop
+    **      D: ...
+    */
+    addrInsTop = sqlite3VdbeAddOp1(v, OP_Rewind, srcTab);
+    addrCont = sqlite3VdbeCurrentAddr(v);
   }else if( pSelect ){
-    sqlite3VdbeAddOp2(v, OP_Goto, 0, iSelectLoop);
-    sqlite3VdbeResolveLabel(v, iInsertBlock);
+    /* This block codes the top of loop only.  The complete loop is the
+    ** following pseudocode (template 3):
+    **
+    **      C: yield X
+    **         if EOF goto D
+    **         insert the select result into 
       from R..R+n
+    **         goto C
+    **      D: ...
+    */
+    addrCont = sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);
+    addrInsTop = sqlite3VdbeAddOp1(v, OP_If, regEof);
   }
 
   /* Allocate registers for holding the rowid of the new row,
@@ -57480,7 +64681,7 @@ SQLITE_PRIVATE void sqlite3Insert(
         VdbeOp *pOp;
         sqlite3ExprCode(pParse, pList->a[keyColumn].pExpr, regRowid);
         pOp = sqlite3VdbeGetOp(v, sqlite3VdbeCurrentAddr(v) - 1);
-        if( pOp && pOp->opcode==OP_Null ){
+        if( pOp && pOp->opcode==OP_Null && !IsVirtual(pTab) ){
           appendFlag = 1;
           pOp->opcode = OP_NewRowid;
           pOp->p1 = baseCur;
@@ -57493,9 +64694,14 @@ SQLITE_PRIVATE void sqlite3Insert(
       */
       if( !appendFlag ){
         int j1;
-        j1 = sqlite3VdbeAddOp1(v, OP_NotNull, regRowid);
-        sqlite3VdbeAddOp3(v, OP_NewRowid, baseCur, regRowid, regAutoinc);
-        sqlite3VdbeJumpHere(v, j1);
+        if( !IsVirtual(pTab) ){
+          j1 = sqlite3VdbeAddOp1(v, OP_NotNull, regRowid);
+          sqlite3VdbeAddOp3(v, OP_NewRowid, baseCur, regRowid, regAutoinc);
+          sqlite3VdbeJumpHere(v, j1);
+        }else{
+          j1 = sqlite3VdbeCurrentAddr(v);
+          sqlite3VdbeAddOp2(v, OP_IsNull, regRowid, j1+2);
+        }
         sqlite3VdbeAddOp1(v, OP_MustBeInt, regRowid);
       }
     }else if( IsVirtual(pTab) ){
@@ -57549,7 +64755,7 @@ SQLITE_PRIVATE void sqlite3Insert(
     */
 #ifndef SQLITE_OMIT_VIRTUALTABLE
     if( IsVirtual(pTab) ){
-      pParse->pVirtualLock = pTab;
+      sqlite3VtabMakeWritable(pParse, pTab);
       sqlite3VdbeAddOp4(v, OP_VUpdate, 1, pTab->nCol+2, regIns,
                      (const char*)pTab->pVtab, P4_VTAB);
     }else
@@ -57594,23 +64800,24 @@ SQLITE_PRIVATE void sqlite3Insert(
     }
   }
 
-  /* The bottom of the loop, if the data source is a SELECT statement
+  /* The bottom of the main insertion loop, if the data source
+  ** is a SELECT statement.
   */
   sqlite3VdbeResolveLabel(v, endOfLoop);
   if( useTempTable ){
-    sqlite3VdbeAddOp2(v, OP_Next, srcTab, iCont);
-    sqlite3VdbeResolveLabel(v, iBreak);
-    sqlite3VdbeAddOp2(v, OP_Close, srcTab, 0);
+    sqlite3VdbeAddOp2(v, OP_Next, srcTab, addrCont);
+    sqlite3VdbeJumpHere(v, addrInsTop);
+    sqlite3VdbeAddOp1(v, OP_Close, srcTab);
   }else if( pSelect ){
-    sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
-    sqlite3VdbeResolveLabel(v, iCleanup);
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrCont);
+    sqlite3VdbeJumpHere(v, addrInsTop);
   }
 
   if( !IsVirtual(pTab) && !isView ){
     /* Close all tables opened */
-    sqlite3VdbeAddOp2(v, OP_Close, baseCur, 0);
+    sqlite3VdbeAddOp1(v, OP_Close, baseCur);
     for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
-      sqlite3VdbeAddOp2(v, OP_Close, idx+baseCur, 0);
+      sqlite3VdbeAddOp1(v, OP_Close, idx+baseCur);
     }
   }
 
@@ -57632,11 +64839,11 @@ SQLITE_PRIVATE void sqlite3Insert(
   }
 
 insert_cleanup:
-  sqlite3SrcListDelete(pTabList);
-  sqlite3ExprListDelete(pList);
-  sqlite3SelectDelete(pSelect);
-  sqlite3IdListDelete(pColumn);
-  sqlite3_free(aRegIdx);
+  sqlite3SrcListDelete(db, pTabList);
+  sqlite3ExprListDelete(db, pList);
+  sqlite3SelectDelete(db, pSelect);
+  sqlite3IdListDelete(db, pColumn);
+  sqlite3DbFree(db, aRegIdx);
 }
 
 /*
@@ -57768,10 +64975,10 @@ SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(
       case OE_Rollback:
       case OE_Abort:
       case OE_Fail: {
-        char *zMsg = 0;
+        char *zMsg;
         sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_CONSTRAINT, onError);
-        sqlite3SetString(&zMsg, pTab->zName, ".", pTab->aCol[i].zName,
-                        " may not be NULL", (char*)0);
+        zMsg = sqlite3MPrintf(pParse->db, "%s.%s may not be NULL",
+                              pTab->zName, pTab->aCol[i].zName);
         sqlite3VdbeChangeP4(v, -1, zMsg, P4_DYNAMIC);
         break;
       }
@@ -57874,6 +65081,7 @@ SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(
     sqlite3VdbeAddOp2(v, OP_SCopy, regRowid, regIdx+i);
     sqlite3VdbeAddOp3(v, OP_MakeRecord, regIdx, pIdx->nColumn+1, aRegIdx[iCur]);
     sqlite3IndexAffinityStr(v, pIdx);
+    sqlite3ExprCacheAffinityChange(pParse, regIdx, pIdx->nColumn+1);
     sqlite3ReleaseTempRange(pParse, regIdx, pIdx->nColumn+1);
 
     /* Find out what action to take in case there is an indexing conflict */
@@ -57895,7 +65103,7 @@ SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(
     regR = sqlite3GetTempReg(pParse);
     sqlite3VdbeAddOp2(v, OP_SCopy, regRowid-hasTwoRowids, regR);
     j3 = sqlite3VdbeAddOp4(v, OP_IsUnique, baseCur+iCur+1, 0,
-                           regR, (char*)(sqlite3_intptr_t)aRegIdx[iCur],
+                           regR, SQLITE_INT_TO_PTR(aRegIdx[iCur]),
                            P4_INT32);
 
     /* Generate code that executes if the new index entry is not unique */
@@ -57988,6 +65196,7 @@ SQLITE_PRIVATE void sqlite3CompleteInsertion(
   regRec = sqlite3GetTempReg(pParse);
   sqlite3VdbeAddOp3(v, OP_MakeRecord, regData, pTab->nCol, regRec);
   sqlite3TableAffinityStr(v, pTab);
+  sqlite3ExprCacheAffinityChange(pParse, regData, pTab->nCol);
 #ifndef SQLITE_OMIT_TRIGGER
   if( newIdx>=0 ){
     sqlite3VdbeAddOp3(v, OP_Insert, newIdx, regRec, regRowid);
@@ -58169,7 +65378,7 @@ static int xferOptimization(
     return 0;   /* tab1 must not have triggers */
   }
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-  if( pDest->isVirtual ){
+  if( pDest->tabFlags & TF_Virtual ){
     return 0;   /* tab1 must not be a virtual table */
   }
 #endif
@@ -58204,7 +65413,7 @@ static int xferOptimization(
   if( pSelect->pPrior ){
     return 0;   /* SELECT may not be a compound query */
   }
-  if( pSelect->isDistinct ){
+  if( pSelect->selFlags & SF_Distinct ){
     return 0;   /* SELECT may not be DISTINCT */
   }
   pEList = pSelect->pEList;
@@ -58230,7 +65439,7 @@ static int xferOptimization(
     return 0;   /* tab1 and tab2 may not be the same table */
   }
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-  if( pSrc->isVirtual ){
+  if( pSrc->tabFlags & TF_Virtual ){
     return 0;   /* tab2 must not be a virtual table */
   }
 #endif
@@ -58321,7 +65530,7 @@ static int xferOptimization(
     addr1 = sqlite3VdbeAddOp2(v, OP_NewRowid, iDest, regRowid);
   }else{
     addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid);
-    assert( pDest->autoInc==0 );
+    assert( (pDest->tabFlags & TF_Autoincrement)==0 );
   }
   sqlite3VdbeAddOp2(v, OP_RowData, iSrc, regData);
   sqlite3VdbeAddOp3(v, OP_Insert, iDest, regData, regRowid);
@@ -58366,6 +65575,11 @@ static int xferOptimization(
 }
 #endif /* SQLITE_OMIT_XFER_OPT */
 
+/* Make sure "isView" gets undefined in case this file becomes part of
+** the amalgamation - so that subsequent files do not see isView as a
+** macro. */
+#undef isView
+
 /************** End of insert.c **********************************************/
 /************** Begin file legacy.c ******************************************/
 /*
@@ -58384,7 +65598,7 @@ static int xferOptimization(
 ** other files are for internal use by SQLite and should not be
 ** accessed by users of the library.
 **
-** $Id: legacy.c,v 1.23 2008/02/13 18:25:27 danielk1977 Exp $
+** $Id: legacy.c,v 1.29 2008/08/02 03:50:39 drh Exp $
 */
 
 
@@ -58413,9 +65627,10 @@ SQLITE_API int sqlite3_exec(
   int nRetry = 0;
   int nCallback;
 
-  if( zSql==0 ) return SQLITE_OK;
+  if( zSql==0 ) zSql = "";
 
   sqlite3_mutex_enter(db->mutex);
+  sqlite3Error(db, SQLITE_OK, 0);
   while( (rc==SQLITE_OK || (rc==SQLITE_SCHEMA && (++nRetry)<2)) && zSql[0] ){
     int nCol;
     char **azVals = 0;
@@ -58433,12 +65648,7 @@ SQLITE_API int sqlite3_exec(
     }
 
     nCallback = 0;
-
     nCol = sqlite3_column_count(pStmt);
-    azCols = sqlite3DbMallocZero(db, 2*nCol*sizeof(const char *) + 1);
-    if( azCols==0 ){
-      goto exec_out;
-    }
 
     while( 1 ){
       int i;
@@ -58448,13 +65658,18 @@ SQLITE_API int sqlite3_exec(
       if( xCallback && (SQLITE_ROW==rc || 
           (SQLITE_DONE==rc && !nCallback && db->flags&SQLITE_NullCallback)) ){
         if( 0==nCallback ){
-          for(i=0; imallocFailed = 1;
+          if( azCols==0 ){
+            azCols = sqlite3DbMallocZero(db, 2*nCol*sizeof(const char*) + 1);
+            if( azCols==0 ){
               goto exec_out;
             }
           }
+          for(i=0; iaggregate_context
+#ifndef SQLITE_OMIT_DEPRECATED
 #define sqlite3_aggregate_count        sqlite3_api->aggregate_count
+#endif
 #define sqlite3_bind_blob              sqlite3_api->bind_blob
 #define sqlite3_bind_double            sqlite3_api->bind_double
 #define sqlite3_bind_int               sqlite3_api->bind_int
@@ -58786,14 +66018,18 @@ struct sqlite3_api_routines {
 #define sqlite3_errmsg                 sqlite3_api->errmsg
 #define sqlite3_errmsg16               sqlite3_api->errmsg16
 #define sqlite3_exec                   sqlite3_api->exec
+#ifndef SQLITE_OMIT_DEPRECATED
 #define sqlite3_expired                sqlite3_api->expired
+#endif
 #define sqlite3_finalize               sqlite3_api->finalize
 #define sqlite3_free                   sqlite3_api->free
 #define sqlite3_free_table             sqlite3_api->free_table
 #define sqlite3_get_autocommit         sqlite3_api->get_autocommit
 #define sqlite3_get_auxdata            sqlite3_api->get_auxdata
 #define sqlite3_get_table              sqlite3_api->get_table
+#ifndef SQLITE_OMIT_DEPRECATED
 #define sqlite3_global_recover         sqlite3_api->global_recover
+#endif
 #define sqlite3_interrupt              sqlite3_api->interruptx
 #define sqlite3_last_insert_rowid      sqlite3_api->last_insert_rowid
 #define sqlite3_libversion             sqlite3_api->libversion
@@ -58831,7 +66067,9 @@ struct sqlite3_api_routines {
 #define sqlite3_thread_cleanup         sqlite3_api->thread_cleanup
 #define sqlite3_total_changes          sqlite3_api->total_changes
 #define sqlite3_trace                  sqlite3_api->trace
+#ifndef SQLITE_OMIT_DEPRECATED
 #define sqlite3_transfer_bindings      sqlite3_api->transfer_bindings
+#endif
 #define sqlite3_update_hook            sqlite3_api->update_hook
 #define sqlite3_user_data              sqlite3_api->user_data
 #define sqlite3_value_blob             sqlite3_api->value_blob
@@ -58875,9 +66113,20 @@ struct sqlite3_api_routines {
 #define sqlite3_vfs_find               sqlite3_api->vfs_find
 #define sqlite3_vfs_register           sqlite3_api->vfs_register
 #define sqlite3_vfs_unregister         sqlite3_api->vfs_unregister
+#define sqlite3_threadsafe             sqlite3_api->xthreadsafe
+#define sqlite3_result_zeroblob        sqlite3_api->result_zeroblob
+#define sqlite3_result_error_code      sqlite3_api->result_error_code
+#define sqlite3_test_control           sqlite3_api->test_control
+#define sqlite3_randomness             sqlite3_api->randomness
+#define sqlite3_context_db_handle      sqlite3_api->context_db_handle
+#define sqlite3_extended_result_codes  sqlite3_api->extended_result_codes
+#define sqlite3_limit                  sqlite3_api->limit
+#define sqlite3_next_stmt              sqlite3_api->next_stmt
+#define sqlite3_sql                    sqlite3_api->sql
+#define sqlite3_status                 sqlite3_api->status
 #endif /* SQLITE_CORE */
 
-#define SQLITE_EXTENSION_INIT1     const sqlite3_api_routines *sqlite3_api;
+#define SQLITE_EXTENSION_INIT1     const sqlite3_api_routines *sqlite3_api = 0;
 #define SQLITE_EXTENSION_INIT2(v)  sqlite3_api = v;
 
 #endif /* _SQLITE3EXT_H_ */
@@ -58885,6 +66134,8 @@ struct sqlite3_api_routines {
 /************** End of sqlite3ext.h ******************************************/
 /************** Continuing where we left off in loadext.c ********************/
 
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
+
 /*
 ** Some API routines are omitted when various features are
 ** excluded from a build of SQLite.  Substitute a NULL pointer
@@ -58982,9 +66233,13 @@ struct sqlite3_api_routines {
 ** also check to make sure that the pointer to the function is
 ** not NULL before calling it.
 */
-SQLITE_PRIVATE const sqlite3_api_routines sqlite3Apis = {
+static const sqlite3_api_routines sqlite3Apis = {
   sqlite3_aggregate_context,
+#ifndef SQLITE_OMIT_DEPRECATED
   sqlite3_aggregate_count,
+#else
+  0,
+#endif
   sqlite3_bind_blob,
   sqlite3_bind_double,
   sqlite3_bind_int,
@@ -59039,7 +66294,11 @@ SQLITE_PRIVATE const sqlite3_api_routines sqlite3Apis = {
   sqlite3_errmsg,
   sqlite3_errmsg16,
   sqlite3_exec,
+#ifndef SQLITE_OMIT_DEPRECATED
   sqlite3_expired,
+#else
+  0,
+#endif
   sqlite3_finalize,
   sqlite3_free,
   sqlite3_free_table,
@@ -59079,10 +66338,18 @@ SQLITE_PRIVATE const sqlite3_api_routines sqlite3Apis = {
   sqlite3_snprintf,
   sqlite3_step,
   sqlite3_table_column_metadata,
+#ifndef SQLITE_OMIT_DEPRECATED
   sqlite3_thread_cleanup,
+#else
+  0,
+#endif
   sqlite3_total_changes,
   sqlite3_trace,
+#ifndef SQLITE_OMIT_DEPRECATED
   sqlite3_transfer_bindings,
+#else
+  0,
+#endif
   sqlite3_update_hook,
   sqlite3_user_data,
   sqlite3_value_blob,
@@ -59133,7 +66400,7 @@ SQLITE_PRIVATE const sqlite3_api_routines sqlite3Apis = {
   sqlite3_file_control,
   sqlite3_memory_highwater,
   sqlite3_memory_used,
-#ifdef SQLITE_MUTEX_NOOP
+#ifdef SQLITE_MUTEX_OMIT
   0, 
   0, 
   0,
@@ -59155,6 +66422,25 @@ SQLITE_PRIVATE const sqlite3_api_routines sqlite3Apis = {
   sqlite3_vfs_find,
   sqlite3_vfs_register,
   sqlite3_vfs_unregister,
+
+  /*
+  ** Added for 3.5.8
+  */
+  sqlite3_threadsafe,
+  sqlite3_result_zeroblob,
+  sqlite3_result_error_code,
+  sqlite3_test_control,
+  sqlite3_randomness,
+  sqlite3_context_db_handle,
+
+  /*
+  ** Added for 3.6.0
+  */
+  sqlite3_extended_result_codes,
+  sqlite3_limit,
+  sqlite3_next_stmt,
+  sqlite3_sql,
+  sqlite3_status,
 };
 
 /*
@@ -59167,7 +66453,7 @@ SQLITE_PRIVATE const sqlite3_api_routines sqlite3Apis = {
 **
 ** If an error occurs and pzErrMsg is not 0, then fill *pzErrMsg with 
 ** error message text.  The calling function should free this memory
-** by calling sqlite3_free().
+** by calling sqlite3DbFree(db, ).
 */
 static int sqlite3LoadExtension(
   sqlite3 *db,          /* Load the extension into this database connection */
@@ -59206,7 +66492,7 @@ static int sqlite3LoadExtension(
       sqlite3_snprintf(sizeof(zErr)-1, zErr, 
           "unable to open shared library [%s]", zFile);
       sqlite3OsDlError(pVfs, sizeof(zErr)-1, zErr);
-      *pzErrMsg = sqlite3DbStrDup(db, zErr);
+      *pzErrMsg = sqlite3DbStrDup(0, zErr);
     }
     return SQLITE_ERROR;
   }
@@ -59219,7 +66505,7 @@ static int sqlite3LoadExtension(
       sqlite3_snprintf(sizeof(zErr)-1, zErr,
           "no entry point [%s] in shared library [%s]", zProc,zFile);
       sqlite3OsDlError(pVfs, sizeof(zErr)-1, zErr);
-      *pzErrMsg = sqlite3DbStrDup(db, zErr);
+      *pzErrMsg = sqlite3DbStrDup(0, zErr);
       sqlite3OsDlClose(pVfs, handle);
     }
     return SQLITE_ERROR;
@@ -59233,18 +66519,17 @@ static int sqlite3LoadExtension(
   }
 
   /* Append the new shared library handle to the db->aExtension array. */
-  db->nExtension++;
-  aHandle = sqlite3DbMallocZero(db, sizeof(handle)*db->nExtension);
+  aHandle = sqlite3DbMallocZero(db, sizeof(handle)*(db->nExtension+1));
   if( aHandle==0 ){
     return SQLITE_NOMEM;
   }
   if( db->nExtension>0 ){
-    memcpy(aHandle, db->aExtension, sizeof(handle)*(db->nExtension-1));
+    memcpy(aHandle, db->aExtension, sizeof(handle)*db->nExtension);
   }
-  sqlite3_free(db->aExtension);
+  sqlite3DbFree(db, db->aExtension);
   db->aExtension = aHandle;
 
-  db->aExtension[db->nExtension-1] = handle;
+  db->aExtension[db->nExtension++] = handle;
   return SQLITE_OK;
 }
 SQLITE_API int sqlite3_load_extension(
@@ -59270,7 +66555,7 @@ SQLITE_PRIVATE void sqlite3CloseExtensions(sqlite3 *db){
   for(i=0; inExtension; i++){
     sqlite3OsDlClose(db->pVfs, db->aExtension[i]);
   }
-  sqlite3_free(db->aExtension);
+  sqlite3DbFree(db, db->aExtension);
 }
 
 /*
@@ -59288,6 +66573,19 @@ SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff){
   return SQLITE_OK;
 }
 
+#endif /* SQLITE_OMIT_LOAD_EXTENSION */
+
+/*
+** The auto-extension code added regardless of whether or not extension
+** loading is supported.  We need a dummy sqlite3Apis pointer for that
+** code if regular extension loading is not available.  This is that
+** dummy pointer.
+*/
+#ifdef SQLITE_OMIT_LOAD_EXTENSION
+static const sqlite3_api_routines sqlite3Apis = { 0 };
+#endif
+
+
 /*
 ** The following object holds the list of automatically loaded
 ** extensions.
@@ -59295,10 +66593,26 @@ SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff){
 ** This list is shared across threads.  The SQLITE_MUTEX_STATIC_MASTER
 ** mutex must be held while accessing this list.
 */
-static struct {
+typedef struct sqlite3ExtType sqlite3ExtType;
+static SQLITE_WSD struct sqlite3ExtType {
   int nExt;        /* Number of entries in aExt[] */          
   void **aExt;     /* Pointers to the extension init functions */
-} autoext = { 0, 0 };
+} sqlite3Autoext = { 0, 0 };
+
+/* The "wsdAutoext" macro will resolve to the autoextension
+** state vector.  If writable static data is unsupported on the target,
+** we have to locate the state vector at run-time.  In the more common
+** case where writable static data is supported, wsdStat can refer directly
+** to the "sqlite3Autoext" state vector declared above.
+*/
+#ifdef SQLITE_OMIT_WSD
+# define wsdAutoextInit \
+  sqlite3ExtType *x = &GLOBAL(sqlite3ExtType,sqlite3Autoext)
+# define wsdAutoext x[0]
+#else
+# define wsdAutoextInit
+# define wsdAutoext sqlite3Autoext
+#endif
 
 
 /*
@@ -59306,40 +66620,59 @@ static struct {
 ** loaded by every new database connection.
 */
 SQLITE_API int sqlite3_auto_extension(void *xInit){
-  int i;
   int rc = SQLITE_OK;
-  sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
-  sqlite3_mutex_enter(mutex);
-  for(i=0; i=autoext.nExt ){
+    if( i>=wsdAutoext.nExt ){
       xInit = 0;
       go = 0;
     }else{
       xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))
-              autoext.aExt[i];
+              wsdAutoext.aExt[i];
     }
     sqlite3_mutex_leave(mutex);
     if( xInit && xInit(db, &zErrmsg, &sqlite3Apis) ){
@@ -59378,8 +66714,6 @@ SQLITE_PRIVATE int sqlite3AutoLoadExtensions(sqlite3 *db){
   return rc;
 }
 
-#endif /* SQLITE_OMIT_LOAD_EXTENSION */
-
 /************** End of loadext.c *********************************************/
 /************** Begin file pragma.c ******************************************/
 /*
@@ -59395,7 +66729,7 @@ SQLITE_PRIVATE int sqlite3AutoLoadExtensions(sqlite3 *db){
 *************************************************************************
 ** This file contains code used to implement the PRAGMA command.
 **
-** $Id: pragma.c,v 1.170 2008/02/13 18:25:27 danielk1977 Exp $
+** $Id: pragma.c,v 1.189 2008/10/10 17:47:21 danielk1977 Exp $
 */
 
 /* Ignore this whole file if pragmas are disabled
@@ -59493,7 +66827,7 @@ static int getTempStore(const char *z){
 static int invalidateTempStorage(Parse *pParse){
   sqlite3 *db = pParse->db;
   if( db->aDb[1].pBt!=0 ){
-    if( !db->autoCommit ){
+    if( !db->autoCommit || sqlite3BtreeIsInReadTrans(db->aDb[1].pBt) ){
       sqlite3ErrorMsg(pParse, "temporary storage cannot be changed "
         "from within a transaction");
       return SQLITE_ERROR;
@@ -59509,7 +66843,7 @@ static int invalidateTempStorage(Parse *pParse){
 #ifndef SQLITE_OMIT_PAGER_PRAGMAS
 /*
 ** If the TEMP database is open, close it and mark the database schema
-** as needing reloading.  This must be done when using the TEMP_STORE
+** as needing reloading.  This must be done when using the SQLITE_TEMP_STORE
 ** or DEFAULT_TEMP_STORE pragmas.
 */
 static int changeTempStorage(Parse *pParse, const char *zStorageType){
@@ -59603,6 +66937,16 @@ static int flagPragma(Parse *pParse, const char *zLeft, const char *zRight){
 }
 #endif /* SQLITE_OMIT_FLAG_PRAGMAS */
 
+static const char *actionName(u8 action){
+  switch( action ){
+    case OE_SetNull:  return "SET NULL";
+    case OE_SetDflt:  return "SET DEFAULT";
+    case OE_Restrict: return "RESTRICT";
+    case OE_Cascade:  return "CASCADE";
+  }
+  return "";
+}
+
 /*
 ** Process a pragma statement.  
 **
@@ -59657,7 +67001,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
     zRight = sqlite3NameFromToken(db, pValue);
   }
 
-  zDb = ((iDb>0)?pDb->zName:0);
+  zDb = ((pId2 && pId2->n>0)?pDb->zName:0);
   if( sqlite3AuthCheck(pParse, SQLITE_PRAGMA, zLeft, zRight, zDb) ){
     goto pragma_out;
   }
@@ -59732,7 +67076,8 @@ SQLITE_PRIVATE void sqlite3Pragma(
       /* Malloc may fail when setting the page-size, as there is an internal
       ** buffer that the pager module resizes using sqlite3_realloc().
       */
-      if( SQLITE_NOMEM==sqlite3BtreeSetPageSize(pBt, atoi(zRight), -1) ){
+      db->nextPagesize = atoi(zRight);
+      if( SQLITE_NOMEM==sqlite3BtreeSetPageSize(pBt, db->nextPagesize, -1) ){
         db->mallocFailed = 1;
       }
     }
@@ -59760,6 +67105,24 @@ SQLITE_PRIVATE void sqlite3Pragma(
   }else
 
   /*
+  **  PRAGMA [database.]page_count
+  **
+  ** Return the number of pages in the specified database.
+  */
+  if( sqlite3StrICmp(zLeft,"page_count")==0 ){
+    Vdbe *v;
+    int iReg;
+    v = sqlite3GetVdbe(pParse);
+    if( !v || sqlite3ReadSchema(pParse) ) goto pragma_out;
+    sqlite3CodeVerifySchema(pParse, iDb);
+    iReg = ++pParse->nMem;
+    sqlite3VdbeAddOp2(v, OP_Pagecount, iDb, iReg);
+    sqlite3VdbeAddOp2(v, OP_ResultRow, iReg, 1);
+    sqlite3VdbeSetNumCols(v, 1);
+    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "page_count", P4_STATIC);
+  }else
+
+  /*
   **  PRAGMA [database.]locking_mode
   **  PRAGMA [database.]locking_mode = (normal|exclusive)
   */
@@ -59805,6 +67168,85 @@ SQLITE_PRIVATE void sqlite3Pragma(
     sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, zRet, 0);
     sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
   }else
+
+  /*
+  **  PRAGMA [database.]journal_mode
+  **  PRAGMA [database.]journal_mode = (delete|persist|off)
+  */
+  if( sqlite3StrICmp(zLeft,"journal_mode")==0 ){
+    int eMode;
+    static char * const azModeName[] = {"delete", "persist", "off", "truncate"};
+
+    if( zRight==0 ){
+      eMode = PAGER_JOURNALMODE_QUERY;
+    }else{
+      int n = strlen(zRight);
+      eMode = sizeof(azModeName)/sizeof(azModeName[0]) - 1;
+      while( eMode>=0 && sqlite3StrNICmp(zRight, azModeName[eMode], n)!=0 ){
+        eMode--;
+      }
+    }
+    if( pId2->n==0 && eMode==PAGER_JOURNALMODE_QUERY ){
+      /* Simple "PRAGMA journal_mode;" statement. This is a query for
+      ** the current default journal mode (which may be different to
+      ** the journal-mode of the main database).
+      */
+      eMode = db->dfltJournalMode;
+    }else{
+      Pager *pPager;
+      if( pId2->n==0 ){
+        /* This indicates that no database name was specified as part
+        ** of the PRAGMA command. In this case the journal-mode must be
+        ** set on all attached databases, as well as the main db file.
+        **
+        ** Also, the sqlite3.dfltJournalMode variable is set so that
+        ** any subsequently attached databases also use the specified
+        ** journal mode.
+        */
+        int ii;
+        assert(pDb==&db->aDb[0]);
+        for(ii=1; iinDb; ii++){
+          if( db->aDb[ii].pBt ){
+            pPager = sqlite3BtreePager(db->aDb[ii].pBt);
+            sqlite3PagerJournalMode(pPager, eMode);
+          }
+        }
+        db->dfltJournalMode = eMode;
+      }
+      pPager = sqlite3BtreePager(pDb->pBt);
+      eMode = sqlite3PagerJournalMode(pPager, eMode);
+    }
+    assert( eMode==PAGER_JOURNALMODE_DELETE
+              || eMode==PAGER_JOURNALMODE_TRUNCATE
+              || eMode==PAGER_JOURNALMODE_PERSIST
+              || eMode==PAGER_JOURNALMODE_OFF );
+    sqlite3VdbeSetNumCols(v, 1);
+    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "journal_mode", P4_STATIC);
+    sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, 
+           azModeName[eMode], P4_STATIC);
+    sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
+  }else
+
+  /*
+  **  PRAGMA [database.]journal_size_limit
+  **  PRAGMA [database.]journal_size_limit=N
+  **
+  ** Get or set the (boolean) value of the database 'auto-vacuum' parameter.
+  */
+  if( sqlite3StrICmp(zLeft,"journal_size_limit")==0 ){
+    Pager *pPager = sqlite3BtreePager(pDb->pBt);
+    i64 iLimit = -2;
+    if( zRight ){
+      int iLimit32 = atoi(zRight);
+      if( iLimit32<-1 ){
+        iLimit32 = -1;
+      }
+      iLimit = iLimit32;
+    }
+    iLimit = sqlite3PagerJournalSizeLimit(pPager, iLimit);
+    returnSingleInt(pParse, "journal_size_limit", (int)iLimit);
+  }else
+
 #endif /* SQLITE_OMIT_PAGER_PRAGMAS */
 
   /*
@@ -59951,25 +67393,29 @@ SQLITE_PRIVATE void sqlite3Pragma(
         sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
       }
     }else{
-      if( zRight[0] 
-       && !sqlite3OsAccess(db->pVfs, zRight, SQLITE_ACCESS_READWRITE) 
-      ){
-        sqlite3ErrorMsg(pParse, "not a writable directory");
-        goto pragma_out;
+#ifndef SQLITE_OMIT_WSD
+      if( zRight[0] ){
+        int rc;
+        int res;
+        rc = sqlite3OsAccess(db->pVfs, zRight, SQLITE_ACCESS_READWRITE, &res);
+        if( rc!=SQLITE_OK || res==0 ){
+          sqlite3ErrorMsg(pParse, "not a writable directory");
+          goto pragma_out;
+        }
       }
-      if( TEMP_STORE==0
-       || (TEMP_STORE==1 && db->temp_store<=1)
-       || (TEMP_STORE==2 && db->temp_store==1)
+      if( SQLITE_TEMP_STORE==0
+       || (SQLITE_TEMP_STORE==1 && db->temp_store<=1)
+       || (SQLITE_TEMP_STORE==2 && db->temp_store==1)
       ){
         invalidateTempStorage(pParse);
       }
       sqlite3_free(sqlite3_temp_directory);
       if( zRight[0] ){
-        sqlite3_temp_directory = zRight;
-        zRight = 0;
+        sqlite3_temp_directory = sqlite3DbStrDup(0, zRight);
       }else{
         sqlite3_temp_directory = 0;
       }
+#endif /* SQLITE_OMIT_WSD */
     }
   }else
 
@@ -60153,24 +67599,32 @@ SQLITE_PRIVATE void sqlite3Pragma(
       pFK = pTab->pFKey;
       if( pFK ){
         int i = 0; 
-        sqlite3VdbeSetNumCols(v, 5);
-        pParse->nMem = 5;
+        sqlite3VdbeSetNumCols(v, 8);
+        pParse->nMem = 8;
         sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "id", P4_STATIC);
         sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "seq", P4_STATIC);
         sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "table", P4_STATIC);
         sqlite3VdbeSetColName(v, 3, COLNAME_NAME, "from", P4_STATIC);
         sqlite3VdbeSetColName(v, 4, COLNAME_NAME, "to", P4_STATIC);
+        sqlite3VdbeSetColName(v, 5, COLNAME_NAME, "on_update", P4_STATIC);
+        sqlite3VdbeSetColName(v, 6, COLNAME_NAME, "on_delete", P4_STATIC);
+        sqlite3VdbeSetColName(v, 7, COLNAME_NAME, "match", P4_STATIC);
         while(pFK){
           int j;
           for(j=0; jnCol; j++){
             char *zCol = pFK->aCol[j].zCol;
+            char *zOnUpdate = (char *)actionName(pFK->updateConf);
+            char *zOnDelete = (char *)actionName(pFK->deleteConf);
             sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
             sqlite3VdbeAddOp2(v, OP_Integer, j, 2);
             sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, pFK->zTo, 0);
             sqlite3VdbeAddOp4(v, OP_String8, 0, 4, 0,
                               pTab->aCol[pFK->aCol[j].iFrom].zName, 0);
             sqlite3VdbeAddOp4(v, zCol ? OP_String8 : OP_Null, 0, 5, 0, zCol, 0);
-            sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 5);
+            sqlite3VdbeAddOp4(v, OP_String8, 0, 6, 0, zOnUpdate, 0);
+            sqlite3VdbeAddOp4(v, OP_String8, 0, 7, 0, zOnDelete, 0);
+            sqlite3VdbeAddOp4(v, OP_String8, 0, 8, 0, "NONE", 0);
+            sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 8);
           }
           ++i;
           pFK = pFK->pNextFrom;
@@ -60287,7 +67741,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
       sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
          sqlite3MPrintf(db, "*** in database %s ***\n", db->aDb[i].zName),
          P4_DYNAMIC);
-      sqlite3VdbeAddOp2(v, OP_Move, 2, 4);
+      sqlite3VdbeAddOp3(v, OP_Move, 2, 4, 1);
       sqlite3VdbeAddOp3(v, OP_Concat, 4, 3, 2);
       sqlite3VdbeAddOp2(v, OP_ResultRow, 2, 1);
       sqlite3VdbeJumpHere(v, addr);
@@ -60319,13 +67773,16 @@ SQLITE_PRIVATE void sqlite3Pragma(
             { OP_Concat,      5,  3,  3},
             { OP_Concat,      6,  3,  3},
             { OP_ResultRow,   3,  1,  0},
+            { OP_IfPos,       1,  0,  0},    /* 9 */
+            { OP_Halt,        0,  0,  0},
           };
-          sqlite3GenerateIndexKey(pParse, pIdx, 1, 3);
+          sqlite3GenerateIndexKey(pParse, pIdx, 1, 3, 1);
           jmp2 = sqlite3VdbeAddOp3(v, OP_Found, j+2, 0, 3);
           addr = sqlite3VdbeAddOpList(v, ArraySize(idxErr), idxErr);
           sqlite3VdbeChangeP4(v, addr+1, "rowid ", P4_STATIC);
           sqlite3VdbeChangeP4(v, addr+3, " missing from index ", P4_STATIC);
           sqlite3VdbeChangeP4(v, addr+4, pIdx->zName, P4_STATIC);
+          sqlite3VdbeJumpHere(v, addr+9);
           sqlite3VdbeJumpHere(v, jmp2);
         }
         sqlite3VdbeAddOp2(v, OP_Next, 1, loopTop+1);
@@ -60471,7 +67928,6 @@ SQLITE_PRIVATE void sqlite3Pragma(
    || sqlite3StrICmp(zLeft, "user_version")==0 
    || sqlite3StrICmp(zLeft, "freelist_count")==0 
   ){
-
     int iCookie;   /* Cookie index. 0 for schema-cookie, 6 for user-cookie. */
     sqlite3VdbeUsesBtree(v, iDb);
     switch( zLeft[0] ){
@@ -60546,6 +68002,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
       sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, zState, P4_STATIC);
       sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 2);
     }
+
   }else
 #endif
 
@@ -60603,8 +68060,8 @@ SQLITE_PRIVATE void sqlite3Pragma(
 #endif
   }
 pragma_out:
-  sqlite3_free(zLeft);
-  sqlite3_free(zRight);
+  sqlite3DbFree(db, zLeft);
+  sqlite3DbFree(db, zRight);
 }
 
 #endif /* SQLITE_OMIT_PRAGMA || SQLITE_OMIT_PARSER */
@@ -60626,17 +68083,27 @@ pragma_out:
 ** interface, and routines that contribute to loading the database schema
 ** from disk.
 **
-** $Id: prepare.c,v 1.78 2008/03/08 12:23:31 drh Exp $
+** $Id: prepare.c,v 1.97 2008/09/08 09:06:19 danielk1977 Exp $
 */
 
 /*
 ** Fill the InitData structure with an error message that indicates
 ** that the database is corrupt.
 */
-static void corruptSchema(InitData *pData, const char *zExtra){
-  if( !pData->db->mallocFailed ){
-    sqlite3SetString(pData->pzErrMsg, "malformed database schema",
-       zExtra!=0 && zExtra[0]!=0 ? " - " : (char*)0, zExtra, (char*)0);
+static void corruptSchema(
+  InitData *pData,     /* Initialization context */
+  const char *zObj,    /* Object being parsed at the point of error */
+  const char *zExtra   /* Error information */
+){
+  sqlite3 *db = pData->db;
+  if( !db->mallocFailed && (db->flags & SQLITE_RecoveryMode)==0 ){
+    if( zObj==0 ) zObj = "?";
+    sqlite3SetString(pData->pzErrMsg, pData->db,
+       "malformed database schema (%s)", zObj);
+    if( zExtra && zExtra[0] ){
+      *pData->pzErrMsg = sqlite3MAppendf(pData->db, *pData->pzErrMsg, "%s - %s",
+                                  *pData->pzErrMsg, zExtra);
+    }
   }
   pData->rc = SQLITE_CORRUPT;
 }
@@ -60659,21 +68126,18 @@ SQLITE_PRIVATE int sqlite3InitCallback(void *pInit, int argc, char **argv, char
   int iDb = pData->iDb;
 
   assert( sqlite3_mutex_held(db->mutex) );
-  pData->rc = SQLITE_OK;
   DbClearProperty(db, iDb, DB_Empty);
   if( db->mallocFailed ){
-    corruptSchema(pData, 0);
+    corruptSchema(pData, argv[0], 0);
     return SQLITE_NOMEM;
   }
 
   assert( argc==3 );
+  assert( iDb>=0 && iDbnDb );
   if( argv==0 ) return 0;   /* Might happen if EMPTY_RESULT_CALLBACKS are on */
   if( argv[1]==0 ){
-    corruptSchema(pData, 0);
-    return 1;
-  }
-  assert( iDb>=0 && iDbnDb );
-  if( argv[2] && argv[2][0] ){
+    corruptSchema(pData, argv[0], 0);
+  }else if( argv[2] && argv[2][0] ){
     /* Call the parser to process a CREATE TABLE, INDEX or VIEW.
     ** But because db->init.busy is set to 1, no VDBE code is generated
     ** or executed.  All the parser does is build the internal data
@@ -60681,24 +68145,27 @@ SQLITE_PRIVATE int sqlite3InitCallback(void *pInit, int argc, char **argv, char
     */
     char *zErr;
     int rc;
+    u8 lookasideEnabled;
     assert( db->init.busy );
     db->init.iDb = iDb;
     db->init.newTnum = atoi(argv[1]);
+    lookasideEnabled = db->lookaside.bEnabled;
+    db->lookaside.bEnabled = 0;
     rc = sqlite3_exec(db, argv[2], 0, 0, &zErr);
     db->init.iDb = 0;
+    db->lookaside.bEnabled = lookasideEnabled;
     assert( rc!=SQLITE_OK || zErr==0 );
     if( SQLITE_OK!=rc ){
       pData->rc = rc;
       if( rc==SQLITE_NOMEM ){
         db->mallocFailed = 1;
       }else if( rc!=SQLITE_INTERRUPT ){
-        corruptSchema(pData, zErr);
+        corruptSchema(pData, argv[0], zErr);
       }
-      sqlite3_free(zErr);
-      return 1;
+      sqlite3DbFree(db, zErr);
     }
   }else if( argv[0]==0 ){
-    corruptSchema(pData, 0);
+    corruptSchema(pData, 0, 0);
   }else{
     /* If the SQL column is blank it means this is an index that
     ** was created to be the PRIMARY KEY or to fulfill a UNIQUE
@@ -60791,17 +68258,18 @@ static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
   azArg[3] = 0;
   initData.db = db;
   initData.iDb = iDb;
+  initData.rc = SQLITE_OK;
   initData.pzErrMsg = pzErrMsg;
   (void)sqlite3SafetyOff(db);
-  rc = sqlite3InitCallback(&initData, 3, (char **)azArg, 0);
+  sqlite3InitCallback(&initData, 3, (char **)azArg, 0);
   (void)sqlite3SafetyOn(db);
-  if( rc ){
+  if( initData.rc ){
     rc = initData.rc;
     goto error_out;
   }
   pTab = sqlite3FindTable(db, zMasterName, db->aDb[iDb].zName);
   if( pTab ){
-    pTab->readOnly = 1;
+    pTab->tabFlags |= TF_Readonly;
   }
 
   /* Create a cursor to hold the database open
@@ -60813,12 +68281,16 @@ static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
     }
     return SQLITE_OK;
   }
+  curMain = sqlite3MallocZero(sqlite3BtreeCursorSize());
+  if( !curMain ){
+    rc = SQLITE_NOMEM;
+    goto error_out;
+  }
   sqlite3BtreeEnter(pDb->pBt);
-  rc = sqlite3BtreeCursor(pDb->pBt, MASTER_ROOT, 0, 0, 0, &curMain);
+  rc = sqlite3BtreeCursor(pDb->pBt, MASTER_ROOT, 0, 0, curMain);
   if( rc!=SQLITE_OK && rc!=SQLITE_EMPTY ){
-    sqlite3SetString(pzErrMsg, sqlite3ErrStr(rc), (char*)0);
-    sqlite3BtreeLeave(pDb->pBt);
-    goto error_out;
+    sqlite3SetString(pzErrMsg, db, "%s", sqlite3ErrStr(rc));
+    goto initone_error_out;
   }
 
   /* Get the database meta information.
@@ -60840,14 +68312,12 @@ static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
   */
   if( rc==SQLITE_OK ){
     int i;
-    for(i=0; rc==SQLITE_OK && ipBt, i+1, (u32 *)&meta[i]);
-    }
-    if( rc ){
-      sqlite3SetString(pzErrMsg, sqlite3ErrStr(rc), (char*)0);
-      sqlite3BtreeCloseCursor(curMain);
-      sqlite3BtreeLeave(pDb->pBt);
-      goto error_out;
+      if( rc ){
+        sqlite3SetString(pzErrMsg, db, "%s", sqlite3ErrStr(rc));
+        goto initone_error_out;
+      }
     }
   }else{
     memset(meta, 0, sizeof(meta));
@@ -60867,11 +68337,10 @@ static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
     }else{
       /* If opening an attached database, the encoding much match ENC(db) */
       if( meta[4]!=ENC(db) ){
-        sqlite3BtreeCloseCursor(curMain);
-        sqlite3SetString(pzErrMsg, "attached databases must use the same"
-            " text encoding as main database", (char*)0);
-        sqlite3BtreeLeave(pDb->pBt);
-        return SQLITE_ERROR;
+        sqlite3SetString(pzErrMsg, db, "attached databases must use the same"
+            " text encoding as main database");
+        rc = SQLITE_ERROR;
+        goto initone_error_out;
       }
     }
   }else{
@@ -60879,11 +68348,13 @@ static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
   }
   pDb->pSchema->enc = ENC(db);
 
-  size = meta[2];
-  if( size==0 ){ size = SQLITE_DEFAULT_CACHE_SIZE; }
-  if( size<0 ) size = -size;
-  pDb->pSchema->cache_size = size;
-  sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
+  if( pDb->pSchema->cache_size==0 ){
+    size = meta[2];
+    if( size==0 ){ size = SQLITE_DEFAULT_CACHE_SIZE; }
+    if( size<0 ) size = -size;
+    pDb->pSchema->cache_size = size;
+    sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
+  }
 
   /*
   ** file_format==1    Version 3.0.0.
@@ -60896,10 +68367,9 @@ static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
     pDb->pSchema->file_format = 1;
   }
   if( pDb->pSchema->file_format>SQLITE_MAX_FILE_FORMAT ){
-    sqlite3BtreeCloseCursor(curMain);
-    sqlite3SetString(pzErrMsg, "unsupported file format", (char*)0);
-    sqlite3BtreeLeave(pDb->pBt);
-    return SQLITE_ERROR;
+    sqlite3SetString(pzErrMsg, db, "unsupported file format");
+    rc = SQLITE_ERROR;
+    goto initone_error_out;
   }
 
   /* Ticket #2804:  When we open a database in the newer file format,
@@ -60934,18 +68404,16 @@ static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
       db->xAuth = xAuth;
     }
 #endif
-    if( rc==SQLITE_ABORT ) rc = initData.rc;
+    if( rc==SQLITE_OK ) rc = initData.rc;
     (void)sqlite3SafetyOn(db);
-    sqlite3_free(zSql);
+    sqlite3DbFree(db, zSql);
 #ifndef SQLITE_OMIT_ANALYZE
     if( rc==SQLITE_OK ){
       sqlite3AnalysisLoad(db, iDb);
     }
 #endif
-    sqlite3BtreeCloseCursor(curMain);
   }
   if( db->mallocFailed ){
-    /* sqlite3SetString(pzErrMsg, "out of memory", (char*)0); */
     rc = SQLITE_NOMEM;
     sqlite3ResetInternalSchema(db, 0);
   }
@@ -60961,6 +68429,14 @@ static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
     DbSetProperty(db, iDb, DB_SchemaLoaded);
     rc = SQLITE_OK;
   }
+
+  /* Jump here for an error that occurs after successfully allocating
+  ** curMain and calling sqlite3BtreeEnter(). For an error that occurs
+  ** before that point, jump to error_out.
+  */
+initone_error_out:
+  sqlite3BtreeCloseCursor(curMain);
+  sqlite3_free(curMain);
   sqlite3BtreeLeave(pDb->pBt);
 
 error_out:
@@ -61047,23 +68523,32 @@ static int schemaIsValid(sqlite3 *db){
   int cookie;
   int allOk = 1;
 
-  assert( sqlite3_mutex_held(db->mutex) );
-  for(iDb=0; allOk && iDbnDb; iDb++){
-    Btree *pBt;
-    pBt = db->aDb[iDb].pBt;
-    if( pBt==0 ) continue;
-    rc = sqlite3BtreeCursor(pBt, MASTER_ROOT, 0, 0, 0, &curTemp);
-    if( rc==SQLITE_OK ){
-      rc = sqlite3BtreeGetMeta(pBt, 1, (u32 *)&cookie);
-      if( rc==SQLITE_OK && cookie!=db->aDb[iDb].pSchema->schema_cookie ){
-        allOk = 0;
+  curTemp = (BtCursor *)sqlite3Malloc(sqlite3BtreeCursorSize());
+  if( curTemp ){
+    assert( sqlite3_mutex_held(db->mutex) );
+    for(iDb=0; allOk && iDbnDb; iDb++){
+      Btree *pBt;
+      pBt = db->aDb[iDb].pBt;
+      if( pBt==0 ) continue;
+      memset(curTemp, 0, sqlite3BtreeCursorSize());
+      rc = sqlite3BtreeCursor(pBt, MASTER_ROOT, 0, 0, curTemp);
+      if( rc==SQLITE_OK ){
+        rc = sqlite3BtreeGetMeta(pBt, 1, (u32 *)&cookie);
+        if( rc==SQLITE_OK && cookie!=db->aDb[iDb].pSchema->schema_cookie ){
+          allOk = 0;
+        }
+        sqlite3BtreeCloseCursor(curTemp);
+      }
+      if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
+        db->mallocFailed = 1;
       }
-      sqlite3BtreeCloseCursor(curTemp);
-    }
-    if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
-      db->mallocFailed = 1;
     }
+    sqlite3_free(curTemp);
+  }else{
+    allOk = 0;
+    db->mallocFailed = 1;
   }
+
   return allOk;
 }
 
@@ -61135,26 +68620,29 @@ static int sqlite3Prepare(
         const char *zDb = db->aDb[i].zName;
         sqlite3Error(db, SQLITE_LOCKED, "database schema is locked: %s", zDb);
         (void)sqlite3SafetyOff(db);
-        return SQLITE_LOCKED;
+        return sqlite3ApiExit(db, SQLITE_LOCKED);
       }
     }
   }
   
   memset(&sParse, 0, sizeof(sParse));
   sParse.db = db;
-  if( nBytes>=0 && zSql[nBytes]!=0 ){
+  if( nBytes>=0 && (nBytes==0 || zSql[nBytes-1]!=0) ){
     char *zSqlCopy;
-    if( SQLITE_MAX_SQL_LENGTH>0 && nBytes>SQLITE_MAX_SQL_LENGTH ){
+    int mxLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
+    if( nBytes>mxLen ){
       sqlite3Error(db, SQLITE_TOOBIG, "statement too long");
       (void)sqlite3SafetyOff(db);
-      return SQLITE_TOOBIG;
+      return sqlite3ApiExit(db, SQLITE_TOOBIG);
     }
     zSqlCopy = sqlite3DbStrNDup(db, zSql, nBytes);
     if( zSqlCopy ){
       sqlite3RunParser(&sParse, zSqlCopy, &zErrMsg);
-      sqlite3_free(zSqlCopy);
+      sqlite3DbFree(db, zSqlCopy);
+      sParse.zTail = &zSql[sParse.zTail-zSqlCopy];
+    }else{
+      sParse.zTail = &zSql[nBytes];
     }
-    sParse.zTail = &zSql[nBytes];
   }else{
     sqlite3RunParser(&sParse, zSql, &zErrMsg);
   }
@@ -61214,7 +68702,7 @@ static int sqlite3Prepare(
 
   if( zErrMsg ){
     sqlite3Error(db, rc, "%s", zErrMsg);
-    sqlite3_free(zErrMsg);
+    sqlite3DbFree(db, zErrMsg);
   }else{
     sqlite3Error(db, rc, 0);
   }
@@ -61270,7 +68758,7 @@ SQLITE_PRIVATE int sqlite3Reprepare(Vdbe *p){
     assert( pNew!=0 );
   }
   sqlite3VdbeSwap((Vdbe*)pNew, p);
-  sqlite3_transfer_bindings(pNew, (sqlite3_stmt*)p);
+  sqlite3TransferBindings(pNew, (sqlite3_stmt*)p);
   sqlite3VdbeResetStepResult((Vdbe*)pNew);
   sqlite3VdbeFinalize((Vdbe*)pNew);
   return 1;
@@ -61349,7 +68837,7 @@ static int sqlite3Prepare16(
     int chars_parsed = sqlite3Utf8CharLen(zSql8, zTail8-zSql8);
     *pzTail = (u8 *)zSql + sqlite3Utf16ByteLen(zSql, chars_parsed);
   }
-  sqlite3_free(zSql8); 
+  sqlite3DbFree(db, zSql8); 
   rc = sqlite3ApiExit(db, rc);
   sqlite3_mutex_leave(db->mutex);
   return rc;
@@ -61406,7 +68894,7 @@ SQLITE_API int sqlite3_prepare16_v2(
 ** This file contains C code routines that are called by the parser
 ** to handle SELECT statements in SQLite.
 **
-** $Id: select.c,v 1.415 2008/03/04 17:45:01 mlcreech Exp $
+** $Id: select.c,v 1.480 2008/10/07 19:53:14 drh Exp $
 */
 
 
@@ -61414,16 +68902,16 @@ SQLITE_API int sqlite3_prepare16_v2(
 ** Delete all the content of a Select structure but do not deallocate
 ** the select structure itself.
 */
-static void clearSelect(Select *p){
-  sqlite3ExprListDelete(p->pEList);
-  sqlite3SrcListDelete(p->pSrc);
-  sqlite3ExprDelete(p->pWhere);
-  sqlite3ExprListDelete(p->pGroupBy);
-  sqlite3ExprDelete(p->pHaving);
-  sqlite3ExprListDelete(p->pOrderBy);
-  sqlite3SelectDelete(p->pPrior);
-  sqlite3ExprDelete(p->pLimit);
-  sqlite3ExprDelete(p->pOffset);
+static void clearSelect(sqlite3 *db, Select *p){
+  sqlite3ExprListDelete(db, p->pEList);
+  sqlite3SrcListDelete(db, p->pSrc);
+  sqlite3ExprDelete(db, p->pWhere);
+  sqlite3ExprListDelete(db, p->pGroupBy);
+  sqlite3ExprDelete(db, p->pHaving);
+  sqlite3ExprListDelete(db, p->pOrderBy);
+  sqlite3SelectDelete(db, p->pPrior);
+  sqlite3ExprDelete(db, p->pLimit);
+  sqlite3ExprDelete(db, p->pOffset);
 }
 
 /*
@@ -61434,6 +68922,7 @@ SQLITE_PRIVATE void sqlite3SelectDestInit(SelectDest *pDest, int eDest, int iPar
   pDest->iParm = iParm;
   pDest->affinity = 0;
   pDest->iMem = 0;
+  pDest->nMem = 0;
 }
 
 
@@ -61471,18 +68960,16 @@ SQLITE_PRIVATE Select *sqlite3SelectNew(
   pNew->pGroupBy = pGroupBy;
   pNew->pHaving = pHaving;
   pNew->pOrderBy = pOrderBy;
-  pNew->isDistinct = isDistinct;
+  pNew->selFlags = isDistinct ? SF_Distinct : 0;
   pNew->op = TK_SELECT;
-  assert( pOffset==0 || pLimit!=0 );
   pNew->pLimit = pLimit;
   pNew->pOffset = pOffset;
-  pNew->iLimit = -1;
-  pNew->iOffset = -1;
   pNew->addrOpenEphm[0] = -1;
   pNew->addrOpenEphm[1] = -1;
   pNew->addrOpenEphm[2] = -1;
-  if( pNew==&standin) {
-    clearSelect(pNew);
+  if( db->mallocFailed ) {
+    clearSelect(db, pNew);
+    if( pNew!=&standin ) sqlite3DbFree(db, pNew);
     pNew = 0;
   }
   return pNew;
@@ -61491,10 +68978,10 @@ SQLITE_PRIVATE Select *sqlite3SelectNew(
 /*
 ** Delete the given Select structure and all of its substructures.
 */
-SQLITE_PRIVATE void sqlite3SelectDelete(Select *p){
+SQLITE_PRIVATE void sqlite3SelectDelete(sqlite3 *db, Select *p){
   if( p ){
-    clearSelect(p);
-    sqlite3_free(p);
+    clearSelect(db, p);
+    sqlite3DbFree(db, p);
   }
 }
 
@@ -61554,12 +69041,11 @@ SQLITE_PRIVATE int sqlite3JoinType(Parse *pParse, Token *pA, Token *pB, Token *p
      (jointype & (JT_INNER|JT_OUTER))==(JT_INNER|JT_OUTER) ||
      (jointype & JT_ERROR)!=0
   ){
-    const char *zSp1 = " ";
-    const char *zSp2 = " ";
-    if( pB==0 ){ zSp1++; }
-    if( pC==0 ){ zSp2++; }
+    const char *zSp = " ";
+    assert( pB!=0 );
+    if( pC==0 ){ zSp++; }
     sqlite3ErrorMsg(pParse, "unknown or unsupported join type: "
-       "%T%s%T%s%T", pA, zSp1, pB, zSp2, pC);
+       "%T %T%s%T", pA, pB, zSp, pC);
     jointype = JT_INNER;
   }else if( jointype & JT_RIGHT ){
     sqlite3ErrorMsg(pParse, 
@@ -61597,12 +69083,32 @@ static void setToken(Token *p, const char *z){
 **    {a"bc}  ->  {"a""bc"}
 */
 static void setQuotedToken(Parse *pParse, Token *p, const char *z){
-  p->z = (u8 *)sqlite3MPrintf(0, "\"%w\"", z);
-  p->dyn = 1;
-  if( p->z ){
-    p->n = strlen((char *)p->z);
+
+  /* Check if the string appears to be quoted using "..." or `...`
+  ** or [...] or '...' or if the string contains any " characters.  
+  ** If it does, then record a version of the string with the special
+  ** characters escaped.
+  */
+  const char *z2 = z;
+  if( *z2!='[' && *z2!='`' && *z2!='\'' ){
+    while( *z2 ){
+      if( *z2=='"' ) break;
+      z2++;
+    }
+  }
+
+  if( *z2 ){
+    /* String contains " characters - copy and quote the string. */
+    p->z = (u8 *)sqlite3MPrintf(pParse->db, "\"%w\"", z);
+    if( p->z ){
+      p->n = strlen((char *)p->z);
+      p->dyn = 1;
+    }
   }else{
-    pParse->db->mallocFailed = 1;
+    /* String contains no " characters - copy the pointer. */
+    p->z = (u8*)z;
+    p->n = (z2 - z);
+    p->dyn = 0;
   }
 }
 
@@ -61615,7 +69121,6 @@ SQLITE_PRIVATE Expr *sqlite3CreateIdExpr(Parse *pParse, const char *zName){
   return sqlite3PExpr(pParse, TK_ID, 0, 0, &dummy);
 }
 
-
 /*
 ** Add a term to the WHERE expression in *ppExpr that requires the
 ** zCol column to be equal in the two tables pTab1 and pTab2.
@@ -61628,7 +69133,8 @@ static void addWhereTerm(
   const Table *pTab2,      /* Second table */
   const char *zAlias2,     /* Alias for second table.  May be NULL */
   int iRightJoinTable,     /* VDBE cursor for the right table */
-  Expr **ppExpr            /* Add the equality term to this expression */
+  Expr **ppExpr,           /* Add the equality term to this expression */
+  int isOuterJoin          /* True if dealing with an OUTER join */
 ){
   Expr *pE1a, *pE1b, *pE1c;
   Expr *pE2a, *pE2b, *pE2c;
@@ -61647,7 +69153,7 @@ static void addWhereTerm(
   pE1c = sqlite3PExpr(pParse, TK_DOT, pE1b, pE1a, 0);
   pE2c = sqlite3PExpr(pParse, TK_DOT, pE2b, pE2a, 0);
   pE = sqlite3PExpr(pParse, TK_EQ, pE1c, pE2c, 0);
-  if( pE ){
+  if( pE && isOuterJoin ){
     ExprSetProperty(pE, EP_FromJoin);
     pE->iRightJoinTable = iRightJoinTable;
   }
@@ -61715,8 +69221,10 @@ static int sqliteProcessJoin(Parse *pParse, Select *p){
   for(i=0; inSrc-1; i++, pRight++, pLeft++){
     Table *pLeftTab = pLeft->pTab;
     Table *pRightTab = pRight->pTab;
+    int isOuter;
 
     if( pLeftTab==0 || pRightTab==0 ) continue;
+    isOuter = (pRight->jointype & JT_OUTER)!=0;
 
     /* When the NATURAL keyword is present, add WHERE clause terms for
     ** every column that the two tables have in common.
@@ -61732,7 +69240,7 @@ static int sqliteProcessJoin(Parse *pParse, Select *p){
         if( columnIndex(pRightTab, zName)>=0 ){
           addWhereTerm(pParse, zName, pLeftTab, pLeft->zAlias, 
                               pRightTab, pRight->zAlias,
-                              pRight->iCursor, &p->pWhere);
+                              pRight->iCursor, &p->pWhere, isOuter);
           
         }
       }
@@ -61750,7 +69258,7 @@ static int sqliteProcessJoin(Parse *pParse, Select *p){
     ** an AND operator.
     */
     if( pRight->pOn ){
-      setJoinExpr(pRight->pOn, pRight->iCursor);
+      if( isOuter ) setJoinExpr(pRight->pOn, pRight->iCursor);
       p->pWhere = sqlite3ExprAnd(pParse->db, p->pWhere, pRight->pOn);
       pRight->pOn = 0;
     }
@@ -61773,7 +69281,7 @@ static int sqliteProcessJoin(Parse *pParse, Select *p){
         }
         addWhereTerm(pParse, zName, pLeftTab, pLeft->zAlias, 
                             pRightTab, pRight->zAlias,
-                            pRight->iCursor, &p->pWhere);
+                            pRight->iCursor, &p->pWhere, isOuter);
       }
     }
   }
@@ -61794,17 +69302,17 @@ static void pushOntoSorter(
   int nExpr = pOrderBy->nExpr;
   int regBase = sqlite3GetTempRange(pParse, nExpr+2);
   int regRecord = sqlite3GetTempReg(pParse);
-  sqlite3ExprCodeExprList(pParse, pOrderBy, regBase);
+  sqlite3ExprCodeExprList(pParse, pOrderBy, regBase, 0);
   sqlite3VdbeAddOp2(v, OP_Sequence, pOrderBy->iECursor, regBase+nExpr);
-  sqlite3VdbeAddOp2(v, OP_Move, regData, regBase+nExpr+1);
+  sqlite3ExprCodeMove(pParse, regData, regBase+nExpr+1, 1);
   sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nExpr + 2, regRecord);
   sqlite3VdbeAddOp2(v, OP_IdxInsert, pOrderBy->iECursor, regRecord);
   sqlite3ReleaseTempReg(pParse, regRecord);
   sqlite3ReleaseTempRange(pParse, regBase, nExpr+2);
-  if( pSelect->iLimit>=0 ){
+  if( pSelect->iLimit ){
     int addr1, addr2;
     int iLimit;
-    if( pSelect->pOffset ){
+    if( pSelect->iOffset ){
       iLimit = pSelect->iOffset+1;
     }else{
       iLimit = pSelect->iLimit;
@@ -61816,7 +69324,7 @@ static void pushOntoSorter(
     sqlite3VdbeAddOp1(v, OP_Last, pOrderBy->iECursor);
     sqlite3VdbeAddOp1(v, OP_Delete, pOrderBy->iECursor);
     sqlite3VdbeJumpHere(v, addr2);
-    pSelect->iLimit = -1;
+    pSelect->iLimit = 0;
   }
 }
 
@@ -61828,7 +69336,7 @@ static void codeOffset(
   Select *p,        /* The SELECT statement being coded */
   int iContinue     /* Jump here to skip the current record */
 ){
-  if( p->iOffset>=0 && iContinue!=0 ){
+  if( p->iOffset && iContinue!=0 ){
     int addr;
     sqlite3VdbeAddOp2(v, OP_AddImm, p->iOffset, -1);
     addr = sqlite3VdbeAddOp1(v, OP_IfNeg, p->iOffset);
@@ -61905,8 +69413,7 @@ static void selectInnerLoop(
   int distinct,           /* If >=0, make sure results are distinct */
   SelectDest *pDest,      /* How to dispose of the results */
   int iContinue,          /* Jump here to continue with next row */
-  int iBreak,             /* Jump here to break out of the inner loop */
-  char *aff               /* affinity string if eDest is SRT_Union */
+  int iBreak              /* Jump here to break out of the inner loop */
 ){
   Vdbe *v = pParse->pVdbe;
   int i;
@@ -61918,11 +69425,7 @@ static void selectInnerLoop(
 
   if( v==0 ) return;
   assert( pEList!=0 );
-
-  /* If there was a LIMIT clause on the SELECT statement, then do the check
-  ** to see if this row should be output.
-  */
-  hasDistinct = distinct>=0 && pEList->nExpr>0;
+  hasDistinct = distinct>=0;
   if( pOrderBy==0 && !hasDistinct ){
     codeOffset(v, p, iContinue);
   }
@@ -61935,7 +69438,14 @@ static void selectInnerLoop(
     nResultCol = pEList->nExpr;
   }
   if( pDest->iMem==0 ){
-    pDest->iMem = sqlite3GetTempRange(pParse, nResultCol);
+    pDest->iMem = pParse->nMem+1;
+    pDest->nMem = nResultCol;
+    pParse->nMem += nResultCol;
+  }else if( pDest->nMem!=nResultCol ){
+    /* This happens when two SELECTs of a compound SELECT have differing
+    ** numbers of result columns.  The error message will be generated by
+    ** a higher-level routine. */
+    return;
   }
   regResult = pDest->iMem;
   if( nColumn>0 ){
@@ -61946,9 +69456,7 @@ static void selectInnerLoop(
     /* If the destination is an EXISTS(...) expression, the actual
     ** values returned by the SELECT are not required.
     */
-    for(i=0; ia[i].pExpr, regResult+i);
-    }
+    sqlite3ExprCodeExprList(pParse, pEList, regResult, eDest==SRT_Output);
   }
   nColumn = nResultCol;
 
@@ -61978,9 +69486,6 @@ static void selectInnerLoop(
       int r1;
       r1 = sqlite3GetTempReg(pParse);
       sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1);
-      if( aff ){
-        sqlite3VdbeChangeP4(v, -1, aff, P4_STATIC);
-      }
       sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm, r1);
       sqlite3ReleaseTempReg(pParse, r1);
       break;
@@ -61991,12 +69496,7 @@ static void selectInnerLoop(
     ** the temporary table iParm.
     */
     case SRT_Except: {
-      int r1;
-      r1 = sqlite3GetTempReg(pParse);
-      sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1);
-      sqlite3VdbeChangeP4(v, -1, aff, P4_STATIC);
-      sqlite3VdbeAddOp2(v, OP_IdxDelete, iParm, r1);
-      sqlite3ReleaseTempReg(pParse, r1);
+      sqlite3VdbeAddOp3(v, OP_IdxDelete, iParm, regResult, nColumn);
       break;
     }
 #endif
@@ -62026,10 +69526,7 @@ static void selectInnerLoop(
     ** item into the set table with bogus data.
     */
     case SRT_Set: {
-      int addr2;
-
       assert( nColumn==1 );
-      addr2 = sqlite3VdbeAddOp1(v, OP_IsNull, regResult);
       p->affinity = sqlite3CompareAffinity(pEList->a[0].pExpr, pDest->affinity);
       if( pOrderBy ){
         /* At first glance you would think we could optimize out the
@@ -62040,10 +69537,10 @@ static void selectInnerLoop(
       }else{
         int r1 = sqlite3GetTempReg(pParse);
         sqlite3VdbeAddOp4(v, OP_MakeRecord, regResult, 1, r1, &p->affinity, 1);
+        sqlite3ExprCacheAffinityChange(pParse, regResult, 1);
         sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm, r1);
         sqlite3ReleaseTempReg(pParse, r1);
       }
-      sqlite3VdbeJumpHere(v, addr2);
       break;
     }
 
@@ -62064,7 +69561,7 @@ static void selectInnerLoop(
       if( pOrderBy ){
         pushOntoSorter(pParse, pOrderBy, p, regResult);
       }else{
-        sqlite3VdbeAddOp2(v, OP_Move, regResult, iParm);
+        sqlite3ExprCodeMove(pParse, regResult, iParm, 1);
         /* The LIMIT clause will jump out of the loop for us */
       }
       break;
@@ -62075,17 +69572,18 @@ static void selectInnerLoop(
     ** case of a subroutine, the subroutine itself is responsible for
     ** popping the data from the stack.
     */
-    case SRT_Subroutine:
-    case SRT_Callback: {
+    case SRT_Coroutine:
+    case SRT_Output: {
       if( pOrderBy ){
         int r1 = sqlite3GetTempReg(pParse);
         sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1);
         pushOntoSorter(pParse, pOrderBy, p, r1);
         sqlite3ReleaseTempReg(pParse, r1);
-      }else if( eDest==SRT_Subroutine ){
-        sqlite3VdbeAddOp2(v, OP_Gosub, 0, iParm);
+      }else if( eDest==SRT_Coroutine ){
+        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
       }else{
         sqlite3VdbeAddOp2(v, OP_ResultRow, regResult, nColumn);
+        sqlite3ExprCacheAffinityChange(pParse, regResult, nColumn);
       }
       break;
     }
@@ -62105,7 +69603,9 @@ static void selectInnerLoop(
 
   /* Jump to the end of the loop if the LIMIT is reached.
   */
-  if( p->iLimit>=0 && pOrderBy==0 ){
+  if( p->iLimit ){
+    assert( pOrderBy==0 );  /* If there is an ORDER BY, the call to
+                            ** pushOntoSorter() would have cleared p->iLimit */
     sqlite3VdbeAddOp2(v, OP_AddImm, p->iLimit, -1);
     sqlite3VdbeAddOp2(v, OP_IfZero, p->iLimit, iBreak);
   }
@@ -62180,10 +69680,10 @@ static void generateSortTail(
   int regRowid;
 
   iTab = pOrderBy->iECursor;
-  if( eDest==SRT_Callback || eDest==SRT_Subroutine ){
+  if( eDest==SRT_Output || eDest==SRT_Coroutine ){
     pseudoTab = pParse->nTab++;
-    sqlite3VdbeAddOp2(v, OP_OpenPseudo, pseudoTab, 0);
-    sqlite3VdbeAddOp2(v, OP_SetNumColumns, pseudoTab, nColumn);
+    sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, nColumn);
+    sqlite3VdbeAddOp2(v, OP_OpenPseudo, pseudoTab, eDest==SRT_Output);
   }
   addr = 1 + sqlite3VdbeAddOp2(v, OP_Sort, iTab, brk);
   codeOffset(v, p, cont);
@@ -62200,33 +69700,33 @@ static void generateSortTail(
     }
 #ifndef SQLITE_OMIT_SUBQUERY
     case SRT_Set: {
-      int j1;
       assert( nColumn==1 );
-      j1 = sqlite3VdbeAddOp1(v, OP_IsNull, regRow);
       sqlite3VdbeAddOp4(v, OP_MakeRecord, regRow, 1, regRowid, &p->affinity, 1);
+      sqlite3ExprCacheAffinityChange(pParse, regRow, 1);
       sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm, regRowid);
-      sqlite3VdbeJumpHere(v, j1);
       break;
     }
     case SRT_Mem: {
       assert( nColumn==1 );
-      sqlite3VdbeAddOp2(v, OP_Move, regRow, iParm);
+      sqlite3ExprCodeMove(pParse, regRow, iParm, 1);
       /* The LIMIT clause will terminate the loop for us */
       break;
     }
 #endif
-    case SRT_Callback:
-    case SRT_Subroutine: {
+    case SRT_Output:
+    case SRT_Coroutine: {
       int i;
       sqlite3VdbeAddOp2(v, OP_Integer, 1, regRowid);
       sqlite3VdbeAddOp3(v, OP_Insert, pseudoTab, regRow, regRowid);
       for(i=0; iiMem+i );
         sqlite3VdbeAddOp3(v, OP_Column, pseudoTab, i, pDest->iMem+i);
       }
-      if( eDest==SRT_Callback ){
+      if( eDest==SRT_Output ){
         sqlite3VdbeAddOp2(v, OP_ResultRow, pDest->iMem, nColumn);
+        sqlite3ExprCacheAffinityChange(pParse, pDest->iMem, nColumn);
       }else{
-        sqlite3VdbeAddOp2(v, OP_Gosub, 0, iParm);
+        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
       }
       break;
     }
@@ -62238,19 +69738,16 @@ static void generateSortTail(
   sqlite3ReleaseTempReg(pParse, regRow);
   sqlite3ReleaseTempReg(pParse, regRowid);
 
-  /* Jump to the end of the loop when the LIMIT is reached
+  /* LIMIT has been implemented by the pushOntoSorter() routine.
   */
-  if( p->iLimit>=0 ){
-    sqlite3VdbeAddOp2(v, OP_AddImm, p->iLimit, -1);
-    sqlite3VdbeAddOp2(v, OP_IfZero, p->iLimit, brk);
-  }
+  assert( p->iLimit==0 );
 
   /* The bottom of the loop
   */
   sqlite3VdbeResolveLabel(v, cont);
   sqlite3VdbeAddOp2(v, OP_Next, iTab, addr);
   sqlite3VdbeResolveLabel(v, brk);
-  if( eDest==SRT_Callback || eDest==SRT_Subroutine ){
+  if( eDest==SRT_Output || eDest==SRT_Coroutine ){
     sqlite3VdbeAddOp2(v, OP_Close, pseudoTab, 0);
   }
 
@@ -62398,6 +69895,7 @@ static void generateColumnTypes(
   SrcList *pTabList,  /* List of tables */
   ExprList *pEList    /* Expressions defining the result set */
 ){
+#ifndef SQLITE_OMIT_DECLTYPE
   Vdbe *v = pParse->pVdbe;
   int i;
   NameContext sNC;
@@ -62405,20 +69903,26 @@ static void generateColumnTypes(
   sNC.pParse = pParse;
   for(i=0; inExpr; i++){
     Expr *p = pEList->a[i].pExpr;
+    const char *zType;
+#ifdef SQLITE_ENABLE_COLUMN_METADATA
     const char *zOrigDb = 0;
     const char *zOrigTab = 0;
     const char *zOrigCol = 0;
-    const char *zType = columnType(&sNC, p, &zOrigDb, &zOrigTab, &zOrigCol);
+    zType = columnType(&sNC, p, &zOrigDb, &zOrigTab, &zOrigCol);
 
     /* The vdbe must make its own copy of the column-type and other 
     ** column specific strings, in case the schema is reset before this
     ** virtual machine is deleted.
     */
-    sqlite3VdbeSetColName(v, i, COLNAME_DECLTYPE, zType, P4_TRANSIENT);
     sqlite3VdbeSetColName(v, i, COLNAME_DATABASE, zOrigDb, P4_TRANSIENT);
     sqlite3VdbeSetColName(v, i, COLNAME_TABLE, zOrigTab, P4_TRANSIENT);
     sqlite3VdbeSetColName(v, i, COLNAME_COLUMN, zOrigCol, P4_TRANSIENT);
+#else
+    zType = columnType(&sNC, p, 0, 0, 0);
+#endif
+    sqlite3VdbeSetColName(v, i, COLNAME_DECLTYPE, zType, P4_TRANSIENT);
   }
+#endif /* SQLITE_OMIT_DECLTYPE */
 }
 
 /*
@@ -62456,9 +69960,7 @@ static void generateColumnNames(
     if( pEList->a[i].zName ){
       char *zName = pEList->a[i].zName;
       sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, strlen(zName));
-      continue;
-    }
-    if( p->op==TK_COLUMN && pTabList ){
+    }else if( (p->op==TK_COLUMN || p->op==TK_AGG_COLUMN) && pTabList ){
       Table *pTab;
       char *zCol;
       int iCol = p->iColumn;
@@ -62472,7 +69974,7 @@ static void generateColumnNames(
       }else{
         zCol = pTab->aCol[iCol].zName;
       }
-      if( !shortNames && !fullNames && p->span.z && p->span.z[0] ){
+      if( !shortNames && !fullNames ){
         sqlite3VdbeSetColName(v, i, COLNAME_NAME, (char*)p->span.z, p->span.n);
       }else if( fullNames || (!shortNames && pTabList->nSrc>1) ){
         char *zName = 0;
@@ -62480,19 +69982,13 @@ static void generateColumnNames(
  
         zTab = pTabList->a[j].zAlias;
         if( fullNames || zTab==0 ) zTab = pTab->zName;
-        sqlite3SetString(&zName, zTab, ".", zCol, (char*)0);
+        zName = sqlite3MPrintf(db, "%s.%s", zTab, zCol);
         sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, P4_DYNAMIC);
       }else{
         sqlite3VdbeSetColName(v, i, COLNAME_NAME, zCol, strlen(zCol));
       }
-    }else if( p->span.z && p->span.z[0] ){
-      sqlite3VdbeSetColName(v, i, COLNAME_NAME, (char*)p->span.z, p->span.n);
-      /* sqlite3VdbeCompressSpace(v, addr); */
     }else{
-      char zName[30];
-      assert( p->op!=TK_COLUMN || pTabList==0 );
-      sqlite3_snprintf(sizeof(zName), zName, "column%d", i+1);
-      sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, 0);
+      sqlite3VdbeSetColName(v, i, COLNAME_NAME, (char*)p->span.z, p->span.n);
     }
   }
   generateColumnTypes(pParse, pTabList, pEList);
@@ -62515,47 +70011,36 @@ static const char *selectOpName(int id){
 #endif /* SQLITE_OMIT_COMPOUND_SELECT */
 
 /*
-** Forward declaration
-*/
-static int prepSelectStmt(Parse*, Select*);
-
-/*
-** Given a SELECT statement, generate a Table structure that describes
-** the result set of that SELECT.
+** Given a an expression list (which is really the list of expressions
+** that form the result set of a SELECT statement) compute appropriate
+** column names for a table that would hold the expression list.
+**
+** All column names will be unique.
+**
+** Only the column names are computed.  Column.zType, Column.zColl,
+** and other fields of Column are zeroed.
+**
+** Return SQLITE_OK on success.  If a memory allocation error occurs,
+** store NULL in *paCol and 0 in *pnCol and return SQLITE_NOMEM.
 */
-SQLITE_PRIVATE Table *sqlite3ResultSetOfSelect(Parse *pParse, char *zTabName, Select *pSelect){
-  Table *pTab;
-  int i, j;
-  ExprList *pEList;
-  Column *aCol, *pCol;
+static int selectColumnsFromExprList(
+  Parse *pParse,          /* Parsing context */
+  ExprList *pEList,       /* Expr list from which to derive column names */
+  int *pnCol,             /* Write the number of columns here */
+  Column **paCol          /* Write the new column list here */
+){
   sqlite3 *db = pParse->db;
+  int i, j, cnt;
+  Column *aCol, *pCol;
+  int nCol;
+  Expr *p;
+  char *zName;
+  int nName;
 
-  while( pSelect->pPrior ) pSelect = pSelect->pPrior;
-  if( prepSelectStmt(pParse, pSelect) ){
-    return 0;
-  }
-  if( sqlite3SelectResolve(pParse, pSelect, 0) ){
-    return 0;
-  }
-  pTab = sqlite3DbMallocZero(db, sizeof(Table) );
-  if( pTab==0 ){
-    return 0;
-  }
-  pTab->nRef = 1;
-  pTab->zName = zTabName ? sqlite3DbStrDup(db, zTabName) : 0;
-  pEList = pSelect->pEList;
-  pTab->nCol = pEList->nExpr;
-  assert( pTab->nCol>0 );
-  pTab->aCol = aCol = sqlite3DbMallocZero(db, sizeof(pTab->aCol[0])*pTab->nCol);
-  for(i=0, pCol=aCol; inCol; i++, pCol++){
-    Expr *p, *pR;
-    char *zType;
-    char *zName;
-    int nName;
-    CollSeq *pColl;
-    int cnt;
-    NameContext sNC;
-    
+  *pnCol = nCol = pEList->nExpr;
+  aCol = *paCol = sqlite3DbMallocZero(db, sizeof(aCol[0])*nCol);
+  if( aCol==0 ) return SQLITE_NOMEM;
+  for(i=0, pCol=aCol; ia[i].pExpr;
@@ -62563,22 +70048,24 @@ SQLITE_PRIVATE Table *sqlite3ResultSetOfSelect(Parse *pParse, char *zTabName, Se
     if( (zName = pEList->a[i].zName)!=0 ){
       /* If the column contains an "AS " phrase, use  as the name */
       zName = sqlite3DbStrDup(db, zName);
-    }else if( p->op==TK_DOT 
-              && (pR=p->pRight)!=0 && pR->token.z && pR->token.z[0] ){
-      /* For columns of the from A.B use B as the name */
-      zName = sqlite3MPrintf(db, "%T", &pR->token);
-    }else if( p->span.z && p->span.z[0] ){
-      /* Use the original text of the column expression as its name */
-      zName = sqlite3MPrintf(db, "%T", &p->span);
     }else{
-      /* If all else fails, make up a name */
-      zName = sqlite3MPrintf(db, "column%d", i+1);
+      Expr *pCol = p;
+      Table *pTab;
+      while( pCol->op==TK_DOT ) pCol = pCol->pRight;
+      if( pCol->op==TK_COLUMN && (pTab = pCol->pTab)!=0 ){
+        /* For columns use the column name name */
+        int iCol = pCol->iColumn;
+        if( iCol<0 ) iCol = pTab->iPKey;
+        zName = sqlite3MPrintf(db, "%s",
+                 iCol>=0 ? pTab->aCol[iCol].zName : "rowid");
+      }else{
+        /* Use the original text of the column expression as its name */
+        zName = sqlite3MPrintf(db, "%T", &pCol->span);
+      }
     }
-    if( !zName || db->mallocFailed ){
-      db->mallocFailed = 1;
-      sqlite3_free(zName);
-      sqlite3DeleteTable(pTab);
-      return 0;
+    if( db->mallocFailed ){
+      sqlite3DbFree(db, zName);
+      break;
     }
     sqlite3Dequote(zName);
 
@@ -62588,621 +70075,186 @@ SQLITE_PRIVATE Table *sqlite3ResultSetOfSelect(Parse *pParse, char *zTabName, Se
     nName = strlen(zName);
     for(j=cnt=0; jzName = zName;
+  }
+  if( db->mallocFailed ){
+    int j;
+    for(j=0; jpSrc;
-    zType = sqlite3DbStrDup(db, columnType(&sNC, p, 0, 0, 0));
-    pCol->zType = zType;
+/*
+** Add type and collation information to a column list based on
+** a SELECT statement.
+** 
+** The column list presumably came from selectColumnNamesFromExprList().
+** The column list has only names, not types or collations.  This
+** routine goes through and adds the types and collations.
+**
+** This routine requires that all indentifiers in the SELECT
+** statement be resolved.
+*/
+static void selectAddColumnTypeAndCollation(
+  Parse *pParse,        /* Parsing contexts */
+  int nCol,             /* Number of columns */
+  Column *aCol,         /* List of columns */
+  Select *pSelect       /* SELECT used to determine types and collations */
+){
+  sqlite3 *db = pParse->db;
+  NameContext sNC;
+  Column *pCol;
+  CollSeq *pColl;
+  int i;
+  Expr *p;
+  struct ExprList_item *a;
+
+  assert( pSelect!=0 );
+  assert( (pSelect->selFlags & SF_Resolved)!=0 );
+  assert( nCol==pSelect->pEList->nExpr || db->mallocFailed );
+  if( db->mallocFailed ) return;
+  memset(&sNC, 0, sizeof(sNC));
+  sNC.pSrcList = pSelect->pSrc;
+  a = pSelect->pEList->a;
+  for(i=0, pCol=aCol; izType = sqlite3DbStrDup(db, columnType(&sNC, p, 0, 0, 0));
     pCol->affinity = sqlite3ExprAffinity(p);
     pColl = sqlite3ExprCollSeq(pParse, p);
     if( pColl ){
       pCol->zColl = sqlite3DbStrDup(db, pColl->zName);
     }
   }
-  pTab->iPKey = -1;
-  return pTab;
 }
 
 /*
-** Prepare a SELECT statement for processing by doing the following
-** things:
-**
-**    (1)  Make sure VDBE cursor numbers have been assigned to every
-**         element of the FROM clause.
-**
-**    (2)  Fill in the pTabList->a[].pTab fields in the SrcList that 
-**         defines FROM clause.  When views appear in the FROM clause,
-**         fill pTabList->a[].pSelect with a copy of the SELECT statement
-**         that implements the view.  A copy is made of the view's SELECT
-**         statement so that we can freely modify or delete that statement
-**         without worrying about messing up the presistent representation
-**         of the view.
-**
-**    (3)  Add terms to the WHERE clause to accomodate the NATURAL keyword
-**         on joins and the ON and USING clause of joins.
-**
-**    (4)  Scan the list of columns in the result set (pEList) looking
-**         for instances of the "*" operator or the TABLE.* operator.
-**         If found, expand each "*" to be every column in every table
-**         and TABLE.* to be every column in TABLE.
-**
-** Return 0 on success.  If there are problems, leave an error message
-** in pParse and return non-zero.
+** Given a SELECT statement, generate a Table structure that describes
+** the result set of that SELECT.
 */
-static int prepSelectStmt(Parse *pParse, Select *p){
-  int i, j, k, rc;
-  SrcList *pTabList;
-  ExprList *pEList;
-  struct SrcList_item *pFrom;
+SQLITE_PRIVATE Table *sqlite3ResultSetOfSelect(Parse *pParse, Select *pSelect){
+  Table *pTab;
   sqlite3 *db = pParse->db;
+  int savedFlags;
 
-  if( p==0 || p->pSrc==0 || db->mallocFailed ){
-    return 1;
+  savedFlags = db->flags;
+  db->flags &= ~SQLITE_FullColNames;
+  db->flags |= SQLITE_ShortColNames;
+  sqlite3SelectPrep(pParse, pSelect, 0);
+  if( pParse->nErr ) return 0;
+  while( pSelect->pPrior ) pSelect = pSelect->pPrior;
+  db->flags = savedFlags;
+  pTab = sqlite3DbMallocZero(db, sizeof(Table) );
+  if( pTab==0 ){
+    return 0;
   }
-  pTabList = p->pSrc;
-  pEList = p->pEList;
-
-  /* Make sure cursor numbers have been assigned to all entries in
-  ** the FROM clause of the SELECT statement.
-  */
-  sqlite3SrcListAssignCursors(pParse, p->pSrc);
+  pTab->db = db;
+  pTab->nRef = 1;
+  pTab->zName = 0;
+  selectColumnsFromExprList(pParse, pSelect->pEList, &pTab->nCol, &pTab->aCol);
+  selectAddColumnTypeAndCollation(pParse, pTab->nCol, pTab->aCol, pSelect);
+  pTab->iPKey = -1;
+  if( db->mallocFailed ){
+    sqlite3DeleteTable(pTab);
+    return 0;
+  }
+  return pTab;
+}
 
-  /* Look up every table named in the FROM clause of the select.  If
-  ** an entry of the FROM clause is a subquery instead of a table or view,
-  ** then create a transient table structure to describe the subquery.
-  */
-  for(i=0, pFrom=pTabList->a; inSrc; i++, pFrom++){
-    Table *pTab;
-    if( pFrom->pTab!=0 ){
-      /* This statement has already been prepared.  There is no need
-      ** to go further. */
-      assert( i==0 );
-      return 0;
+/*
+** Get a VDBE for the given parser context.  Create a new one if necessary.
+** If an error occurs, return NULL and leave a message in pParse.
+*/
+SQLITE_PRIVATE Vdbe *sqlite3GetVdbe(Parse *pParse){
+  Vdbe *v = pParse->pVdbe;
+  if( v==0 ){
+    v = pParse->pVdbe = sqlite3VdbeCreate(pParse->db);
+#ifndef SQLITE_OMIT_TRACE
+    if( v ){
+      sqlite3VdbeAddOp0(v, OP_Trace);
     }
-    if( pFrom->zName==0 ){
-#ifndef SQLITE_OMIT_SUBQUERY
-      /* A sub-query in the FROM clause of a SELECT */
-      assert( pFrom->pSelect!=0 );
-      if( pFrom->zAlias==0 ){
-        pFrom->zAlias =
-          sqlite3MPrintf(db, "sqlite_subquery_%p_", (void*)pFrom->pSelect);
-      }
-      assert( pFrom->pTab==0 );
-      pFrom->pTab = pTab = 
-        sqlite3ResultSetOfSelect(pParse, pFrom->zAlias, pFrom->pSelect);
-      if( pTab==0 ){
-        return 1;
-      }
-      /* The isEphem flag indicates that the Table structure has been
-      ** dynamically allocated and may be freed at any time.  In other words,
-      ** pTab is not pointing to a persistent table structure that defines
-      ** part of the schema. */
-      pTab->isEphem = 1;
-#endif
-    }else{
-      /* An ordinary table or view name in the FROM clause */
-      assert( pFrom->pTab==0 );
-      pFrom->pTab = pTab = 
-        sqlite3LocateTable(pParse,0,pFrom->zName,pFrom->zDatabase);
-      if( pTab==0 ){
-        return 1;
-      }
-      pTab->nRef++;
-#if !defined(SQLITE_OMIT_VIEW) || !defined (SQLITE_OMIT_VIRTUALTABLE)
-      if( pTab->pSelect || IsVirtual(pTab) ){
-        /* We reach here if the named table is a really a view */
-        if( sqlite3ViewGetColumnNames(pParse, pTab) ){
-          return 1;
-        }
-        /* If pFrom->pSelect!=0 it means we are dealing with a
-        ** view within a view.  The SELECT structure has already been
-        ** copied by the outer view so we can skip the copy step here
-        ** in the inner view.
-        */
-        if( pFrom->pSelect==0 ){
-          pFrom->pSelect = sqlite3SelectDup(db, pTab->pSelect);
-        }
-      }
 #endif
-    }
   }
+  return v;
+}
 
-  /* Process NATURAL keywords, and ON and USING clauses of joins.
-  */
-  if( sqliteProcessJoin(pParse, p) ) return 1;
 
-  /* For every "*" that occurs in the column list, insert the names of
-  ** all columns in all tables.  And for every TABLE.* insert the names
-  ** of all columns in TABLE.  The parser inserted a special expression
-  ** with the TK_ALL operator for each "*" that it found in the column list.
-  ** The following code just has to locate the TK_ALL expressions and expand
-  ** each one to the list of all columns in all tables.
-  **
-  ** The first loop just checks to see if there are any "*" operators
-  ** that need expanding.
+/*
+** Compute the iLimit and iOffset fields of the SELECT based on the
+** pLimit and pOffset expressions.  pLimit and pOffset hold the expressions
+** that appear in the original SQL statement after the LIMIT and OFFSET
+** keywords.  Or NULL if those keywords are omitted. iLimit and iOffset 
+** are the integer memory register numbers for counters used to compute 
+** the limit and offset.  If there is no limit and/or offset, then 
+** iLimit and iOffset are negative.
+**
+** This routine changes the values of iLimit and iOffset only if
+** a limit or offset is defined by pLimit and pOffset.  iLimit and
+** iOffset should have been preset to appropriate default values
+** (usually but not always -1) prior to calling this routine.
+** Only if pLimit!=0 or pOffset!=0 do the limit registers get
+** redefined.  The UNION ALL operator uses this property to force
+** the reuse of the same limit and offset registers across multiple
+** SELECT statements.
+*/
+static void computeLimitRegisters(Parse *pParse, Select *p, int iBreak){
+  Vdbe *v = 0;
+  int iLimit = 0;
+  int iOffset;
+  int addr1;
+  if( p->iLimit ) return;
+
+  /* 
+  ** "LIMIT -1" always shows all rows.  There is some
+  ** contraversy about what the correct behavior should be.
+  ** The current implementation interprets "LIMIT 0" to mean
+  ** no rows.
   */
-  for(k=0; knExpr; k++){
-    Expr *pE = pEList->a[k].pExpr;
-    if( pE->op==TK_ALL ) break;
-    if( pE->op==TK_DOT && pE->pRight && pE->pRight->op==TK_ALL
-         && pE->pLeft && pE->pLeft->op==TK_ID ) break;
+  if( p->pLimit ){
+    p->iLimit = iLimit = ++pParse->nMem;
+    v = sqlite3GetVdbe(pParse);
+    if( v==0 ) return;
+    sqlite3ExprCode(pParse, p->pLimit, iLimit);
+    sqlite3VdbeAddOp1(v, OP_MustBeInt, iLimit);
+    VdbeComment((v, "LIMIT counter"));
+    sqlite3VdbeAddOp2(v, OP_IfZero, iLimit, iBreak);
   }
-  rc = 0;
-  if( knExpr ){
-    /*
-    ** If we get here it means the result set contains one or more "*"
-    ** operators that need to be expanded.  Loop through each expression
-    ** in the result set and expand them one by one.
-    */
-    struct ExprList_item *a = pEList->a;
-    ExprList *pNew = 0;
-    int flags = pParse->db->flags;
-    int longNames = (flags & SQLITE_FullColNames)!=0 &&
-                      (flags & SQLITE_ShortColNames)==0;
-
-    for(k=0; knExpr; k++){
-      Expr *pE = a[k].pExpr;
-      if( pE->op!=TK_ALL &&
-           (pE->op!=TK_DOT || pE->pRight==0 || pE->pRight->op!=TK_ALL) ){
-        /* This particular expression does not need to be expanded.
-        */
-        pNew = sqlite3ExprListAppend(pParse, pNew, a[k].pExpr, 0);
-        if( pNew ){
-          pNew->a[pNew->nExpr-1].zName = a[k].zName;
-        }else{
-          rc = 1;
-        }
-        a[k].pExpr = 0;
-        a[k].zName = 0;
-      }else{
-        /* This expression is a "*" or a "TABLE.*" and needs to be
-        ** expanded. */
-        int tableSeen = 0;      /* Set to 1 when TABLE matches */
-        char *zTName;            /* text of name of TABLE */
-        if( pE->op==TK_DOT && pE->pLeft ){
-          zTName = sqlite3NameFromToken(db, &pE->pLeft->token);
-        }else{
-          zTName = 0;
-        }
-        for(i=0, pFrom=pTabList->a; inSrc; i++, pFrom++){
-          Table *pTab = pFrom->pTab;
-          char *zTabName = pFrom->zAlias;
-          if( zTabName==0 || zTabName[0]==0 ){ 
-            zTabName = pTab->zName;
-          }
-          if( zTName && (zTabName==0 || zTabName[0]==0 || 
-                 sqlite3StrICmp(zTName, zTabName)!=0) ){
-            continue;
-          }
-          tableSeen = 1;
-          for(j=0; jnCol; j++){
-            Expr *pExpr, *pRight;
-            char *zName = pTab->aCol[j].zName;
-
-            /* If a column is marked as 'hidden' (currently only possible
-            ** for virtual tables), do not include it in the expanded
-            ** result-set list.
-            */
-            if( IsHiddenColumn(&pTab->aCol[j]) ){
-              assert(IsVirtual(pTab));
-              continue;
-            }
-
-            if( i>0 ){
-              struct SrcList_item *pLeft = &pTabList->a[i-1];
-              if( (pLeft[1].jointype & JT_NATURAL)!=0 &&
-                        columnIndex(pLeft->pTab, zName)>=0 ){
-                /* In a NATURAL join, omit the join columns from the 
-                ** table on the right */
-                continue;
-              }
-              if( sqlite3IdListIndex(pLeft[1].pUsing, zName)>=0 ){
-                /* In a join with a USING clause, omit columns in the
-                ** using clause from the table on the right. */
-                continue;
-              }
-            }
-            pRight = sqlite3PExpr(pParse, TK_ID, 0, 0, 0);
-            if( pRight==0 ) break;
-            setQuotedToken(pParse, &pRight->token, zName);
-            if( zTabName && (longNames || pTabList->nSrc>1) ){
-              Expr *pLeft = sqlite3PExpr(pParse, TK_ID, 0, 0, 0);
-              pExpr = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight, 0);
-              if( pExpr==0 ) break;
-              setQuotedToken(pParse, &pLeft->token, zTabName);
-              setToken(&pExpr->span, 
-                  sqlite3MPrintf(db, "%s.%s", zTabName, zName));
-              pExpr->span.dyn = 1;
-              pExpr->token.z = 0;
-              pExpr->token.n = 0;
-              pExpr->token.dyn = 0;
-            }else{
-              pExpr = pRight;
-              pExpr->span = pExpr->token;
-              pExpr->span.dyn = 0;
-            }
-            if( longNames ){
-              pNew = sqlite3ExprListAppend(pParse, pNew, pExpr, &pExpr->span);
-            }else{
-              pNew = sqlite3ExprListAppend(pParse, pNew, pExpr, &pRight->token);
-            }
-          }
-        }
-        if( !tableSeen ){
-          if( zTName ){
-            sqlite3ErrorMsg(pParse, "no such table: %s", zTName);
-          }else{
-            sqlite3ErrorMsg(pParse, "no tables specified");
-          }
-          rc = 1;
-        }
-        sqlite3_free(zTName);
-      }
-    }
-    sqlite3ExprListDelete(pEList);
-    p->pEList = pNew;
-  }
-  if( p->pEList && p->pEList->nExpr>SQLITE_MAX_COLUMN ){
-    sqlite3ErrorMsg(pParse, "too many columns in result set");
-    rc = SQLITE_ERROR;
-  }
-  if( db->mallocFailed ){
-    rc = SQLITE_NOMEM;
-  }
-  return rc;
-}
-
-/*
-** pE is a pointer to an expression which is a single term in
-** ORDER BY or GROUP BY clause.
-**
-** If pE evaluates to an integer constant i, then return i.
-** This is an indication to the caller that it should sort
-** by the i-th column of the result set.
-**
-** If pE is a well-formed expression and the SELECT statement
-** is not compound, then return 0.  This indicates to the
-** caller that it should sort by the value of the ORDER BY
-** expression.
-**
-** If the SELECT is compound, then attempt to match pE against
-** result set columns in the left-most SELECT statement.  Return
-** the index i of the matching column, as an indication to the 
-** caller that it should sort by the i-th column.  If there is
-** no match, return -1 and leave an error message in pParse.
-*/
-static int matchOrderByTermToExprList(
-  Parse *pParse,     /* Parsing context for error messages */
-  Select *pSelect,   /* The SELECT statement with the ORDER BY clause */
-  Expr *pE,          /* The specific ORDER BY term */
-  int idx,           /* When ORDER BY term is this */
-  int isCompound,    /* True if this is a compound SELECT */
-  u8 *pHasAgg        /* True if expression contains aggregate functions */
-){
-  int i;             /* Loop counter */
-  ExprList *pEList;  /* The columns of the result set */
-  NameContext nc;    /* Name context for resolving pE */
-
-
-  /* If the term is an integer constant, return the value of that
-  ** constant */
-  pEList = pSelect->pEList;
-  if( sqlite3ExprIsInteger(pE, &i) ){
-    if( i<=0 ){
-      /* If i is too small, make it too big.  That way the calling
-      ** function still sees a value that is out of range, but does
-      ** not confuse the column number with 0 or -1 result code.
-      */
-      i = pEList->nExpr+1;
-    }
-    return i;
-  }
-
-  /* If the term is a simple identifier that try to match that identifier
-  ** against a column name in the result set.
-  */
-  if( pE->op==TK_ID || (pE->op==TK_STRING && pE->token.z[0]!='\'') ){
-    sqlite3 *db = pParse->db;
-    char *zCol = sqlite3NameFromToken(db, &pE->token);
-    if( zCol==0 ){
-      return -1;
-    }
-    for(i=0; inExpr; i++){
-      char *zAs = pEList->a[i].zName;
-      if( zAs!=0 && sqlite3StrICmp(zAs, zCol)==0 ){
-        sqlite3_free(zCol);
-        return i+1;
-      }
-    }
-    sqlite3_free(zCol);
-  }
-
-  /* Resolve all names in the ORDER BY term expression
-  */
-  memset(&nc, 0, sizeof(nc));
-  nc.pParse = pParse;
-  nc.pSrcList = pSelect->pSrc;
-  nc.pEList = pEList;
-  nc.allowAgg = 1;
-  nc.nErr = 0;
-  if( sqlite3ExprResolveNames(&nc, pE) ){
-    if( isCompound ){
-      sqlite3ErrorClear(pParse);
-      return 0;
-    }else{
-      return -1;
-    }
-  }
-  if( nc.hasAgg && pHasAgg ){
-    *pHasAgg = 1;
-  }
-
-  /* For a compound SELECT, we need to try to match the ORDER BY
-  ** expression against an expression in the result set
-  */
-  if( isCompound ){
-    for(i=0; inExpr; i++){
-      if( sqlite3ExprCompare(pEList->a[i].pExpr, pE) ){
-        return i+1;
-      }
-    }
-  }
-  return 0;
-}
-
-
-/*
-** Analyze and ORDER BY or GROUP BY clause in a simple SELECT statement.
-** Return the number of errors seen.
-**
-** Every term of the ORDER BY or GROUP BY clause needs to be an
-** expression.  If any expression is an integer constant, then
-** that expression is replaced by the corresponding 
-** expression from the result set.
-*/
-static int processOrderGroupBy(
-  Parse *pParse,        /* Parsing context.  Leave error messages here */
-  Select *pSelect,      /* The SELECT statement containing the clause */
-  ExprList *pOrderBy,   /* The ORDER BY or GROUP BY clause to be processed */
-  int isOrder,          /* 1 for ORDER BY.  0 for GROUP BY */
-  u8 *pHasAgg           /* Set to TRUE if any term contains an aggregate */
-){
-  int i;
-  sqlite3 *db = pParse->db;
-  ExprList *pEList;
-
-  if( pOrderBy==0 || pParse->db->mallocFailed ) return 0;
-  if( pOrderBy->nExpr>SQLITE_MAX_COLUMN ){
-    const char *zType = isOrder ? "ORDER" : "GROUP";
-    sqlite3ErrorMsg(pParse, "too many terms in %s BY clause", zType);
-    return 1;
-  }
-  pEList = pSelect->pEList;
-  if( pEList==0 ){
-    return 0;
-  }
-  for(i=0; inExpr; i++){
-    int iCol;
-    Expr *pE = pOrderBy->a[i].pExpr;
-    iCol = matchOrderByTermToExprList(pParse, pSelect, pE, i+1, 0, pHasAgg);
-    if( iCol<0 ){
-      return 1;
-    }
-    if( iCol>pEList->nExpr ){
-      const char *zType = isOrder ? "ORDER" : "GROUP";
-      sqlite3ErrorMsg(pParse, 
-         "%r %s BY term out of range - should be "
-         "between 1 and %d", i+1, zType, pEList->nExpr);
-      return 1;
-    }
-    if( iCol>0 ){
-      CollSeq *pColl = pE->pColl;
-      int flags = pE->flags & EP_ExpCollate;
-      sqlite3ExprDelete(pE);
-      pE = sqlite3ExprDup(db, pEList->a[iCol-1].pExpr);
-      pOrderBy->a[i].pExpr = pE;
-      if( pE && pColl && flags ){
-        pE->pColl = pColl;
-        pE->flags |= flags;
-      }
-    }
-  }
-  return 0;
-}
-
-/*
-** Analyze and ORDER BY or GROUP BY clause in a SELECT statement.  Return
-** the number of errors seen.
-**
-** The processing depends on whether the SELECT is simple or compound.
-** For a simple SELECT statement, evry term of the ORDER BY or GROUP BY
-** clause needs to be an expression.  If any expression is an integer
-** constant, then that expression is replaced by the corresponding 
-** expression from the result set.
-**
-** For compound SELECT statements, every expression needs to be of
-** type TK_COLUMN with a iTable value as given in the 4th parameter.
-** If any expression is an integer, that becomes the column number.
-** Otherwise, match the expression against result set columns from
-** the left-most SELECT.
-*/
-static int processCompoundOrderBy(
-  Parse *pParse,        /* Parsing context.  Leave error messages here */
-  Select *pSelect,      /* The SELECT statement containing the ORDER BY */
-  int iTable            /* Output table for compound SELECT statements */
-){
-  int i;
-  ExprList *pOrderBy;
-  ExprList *pEList;
-  sqlite3 *db;
-  int moreToDo = 1;
-
-  pOrderBy = pSelect->pOrderBy;
-  if( pOrderBy==0 ) return 0;
-  if( pOrderBy->nExpr>SQLITE_MAX_COLUMN ){
-    sqlite3ErrorMsg(pParse, "too many terms in ORDER BY clause");
-    return 1;
-  }
-  db = pParse->db;
-  for(i=0; inExpr; i++){
-    pOrderBy->a[i].done = 0;
-  }
-  while( pSelect->pPrior ){
-    pSelect = pSelect->pPrior;
-  }
-  while( pSelect && moreToDo ){
-    moreToDo = 0;
-    for(i=0; inExpr; i++){
-      int iCol = -1;
-      Expr *pE, *pDup;
-      if( pOrderBy->a[i].done ) continue;
-      pE = pOrderBy->a[i].pExpr;
-      pDup = sqlite3ExprDup(db, pE);
-      if( !db->mallocFailed ){
-        assert(pDup);
-        iCol = matchOrderByTermToExprList(pParse, pSelect, pDup, i+1, 1, 0);
-      }
-      sqlite3ExprDelete(pDup);
-      if( iCol<0 ){
-        return 1;
-      }
-      pEList = pSelect->pEList;
-      if( pEList==0 ){
-        return 1;
-      }
-      if( iCol>pEList->nExpr ){
-        sqlite3ErrorMsg(pParse, 
-           "%r ORDER BY term out of range - should be "
-           "between 1 and %d", i+1, pEList->nExpr);
-        return 1;
-      }
-      if( iCol>0 ){
-        pE->op = TK_COLUMN;
-        pE->iTable = iTable;
-        pE->iAgg = -1;
-        pE->iColumn = iCol-1;
-        pE->pTab = 0;
-        pOrderBy->a[i].done = 1;
-      }else{
-        moreToDo = 1;
-      }
-    }
-    pSelect = pSelect->pNext;
-  }
-  for(i=0; inExpr; i++){
-    if( pOrderBy->a[i].done==0 ){
-      sqlite3ErrorMsg(pParse, "%r ORDER BY term does not match any "
-            "column in the result set", i+1);
-      return 1;
-    }
-  }
-  return 0;
-}
-
-/*
-** Get a VDBE for the given parser context.  Create a new one if necessary.
-** If an error occurs, return NULL and leave a message in pParse.
-*/
-SQLITE_PRIVATE Vdbe *sqlite3GetVdbe(Parse *pParse){
-  Vdbe *v = pParse->pVdbe;
-  if( v==0 ){
-    v = pParse->pVdbe = sqlite3VdbeCreate(pParse->db);
-#ifndef SQLITE_OMIT_TRACE
-    if( v ){
-      sqlite3VdbeAddOp0(v, OP_Trace);
-    }
-#endif
-  }
-  return v;
-}
-
-
-/*
-** Compute the iLimit and iOffset fields of the SELECT based on the
-** pLimit and pOffset expressions.  pLimit and pOffset hold the expressions
-** that appear in the original SQL statement after the LIMIT and OFFSET
-** keywords.  Or NULL if those keywords are omitted. iLimit and iOffset 
-** are the integer memory register numbers for counters used to compute 
-** the limit and offset.  If there is no limit and/or offset, then 
-** iLimit and iOffset are negative.
-**
-** This routine changes the values of iLimit and iOffset only if
-** a limit or offset is defined by pLimit and pOffset.  iLimit and
-** iOffset should have been preset to appropriate default values
-** (usually but not always -1) prior to calling this routine.
-** Only if pLimit!=0 or pOffset!=0 do the limit registers get
-** redefined.  The UNION ALL operator uses this property to force
-** the reuse of the same limit and offset registers across multiple
-** SELECT statements.
-*/
-static void computeLimitRegisters(Parse *pParse, Select *p, int iBreak){
-  Vdbe *v = 0;
-  int iLimit = 0;
-  int iOffset;
-  int addr1;
-
-  /* 
-  ** "LIMIT -1" always shows all rows.  There is some
-  ** contraversy about what the correct behavior should be.
-  ** The current implementation interprets "LIMIT 0" to mean
-  ** no rows.
-  */
-  if( p->pLimit ){
-    p->iLimit = iLimit = ++pParse->nMem;
-    v = sqlite3GetVdbe(pParse);
-    if( v==0 ) return;
-    sqlite3ExprCode(pParse, p->pLimit, iLimit);
-    sqlite3VdbeAddOp1(v, OP_MustBeInt, iLimit);
-    VdbeComment((v, "LIMIT counter"));
-    sqlite3VdbeAddOp2(v, OP_IfZero, iLimit, iBreak);
-  }
-  if( p->pOffset ){
-    p->iOffset = iOffset = ++pParse->nMem;
-    if( p->pLimit ){
-      pParse->nMem++;   /* Allocate an extra register for limit+offset */
-    }
-    v = sqlite3GetVdbe(pParse);
-    if( v==0 ) return;
-    sqlite3ExprCode(pParse, p->pOffset, iOffset);
-    sqlite3VdbeAddOp1(v, OP_MustBeInt, iOffset);
-    VdbeComment((v, "OFFSET counter"));
-    addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iOffset);
-    sqlite3VdbeAddOp2(v, OP_Integer, 0, iOffset);
-    sqlite3VdbeJumpHere(v, addr1);
-    if( p->pLimit ){
-      sqlite3VdbeAddOp3(v, OP_Add, iLimit, iOffset, iOffset+1);
-      VdbeComment((v, "LIMIT+OFFSET"));
-      addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iLimit);
-      sqlite3VdbeAddOp2(v, OP_Integer, -1, iOffset+1);
-      sqlite3VdbeJumpHere(v, addr1);
-    }
-  }
-}
-
-/*
-** Allocate a virtual index to use for sorting.
-*/
-static void createSortingIndex(Parse *pParse, Select *p, ExprList *pOrderBy){
-  if( pOrderBy ){
-    int addr;
-    assert( pOrderBy->iECursor==0 );
-    pOrderBy->iECursor = pParse->nTab++;
-    addr = sqlite3VdbeAddOp2(pParse->pVdbe, OP_OpenEphemeral,
-                            pOrderBy->iECursor, pOrderBy->nExpr+1);
-    assert( p->addrOpenEphm[2] == -1 );
-    p->addrOpenEphm[2] = addr;
-  }
-}
+  if( p->pOffset ){
+    p->iOffset = iOffset = ++pParse->nMem;
+    if( p->pLimit ){
+      pParse->nMem++;   /* Allocate an extra register for limit+offset */
+    }
+    v = sqlite3GetVdbe(pParse);
+    if( v==0 ) return;
+    sqlite3ExprCode(pParse, p->pOffset, iOffset);
+    sqlite3VdbeAddOp1(v, OP_MustBeInt, iOffset);
+    VdbeComment((v, "OFFSET counter"));
+    addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iOffset);
+    sqlite3VdbeAddOp2(v, OP_Integer, 0, iOffset);
+    sqlite3VdbeJumpHere(v, addr1);
+    if( p->pLimit ){
+      sqlite3VdbeAddOp3(v, OP_Add, iLimit, iOffset, iOffset+1);
+      VdbeComment((v, "LIMIT+OFFSET"));
+      addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iLimit);
+      sqlite3VdbeAddOp2(v, OP_Integer, -1, iOffset+1);
+      sqlite3VdbeJumpHere(v, addr1);
+    }
+  }
+}
 
 #ifndef SQLITE_OMIT_COMPOUND_SELECT
 /*
@@ -63227,10 +70279,19 @@ static CollSeq *multiSelectCollSeq(Parse *pParse, Select *p, int iCol){
 }
 #endif /* SQLITE_OMIT_COMPOUND_SELECT */
 
+/* Forward reference */
+static int multiSelectOrderBy(
+  Parse *pParse,        /* Parsing context */
+  Select *p,            /* The right-most of SELECTs to be coded */
+  SelectDest *pDest     /* What to do with query results */
+);
+
+
 #ifndef SQLITE_OMIT_COMPOUND_SELECT
 /*
-** This routine is called to process a query that is really the union
-** or intersection of two or more separate queries.
+** This routine is called to process a compound query form from
+** two or more separate queries using UNION, UNION ALL, EXCEPT, or
+** INTERSECT
 **
 ** "p" points to the right-most of the two queries.  the query on the
 ** left is p->pPrior.  The left query could also be a compound query
@@ -63261,30 +70322,24 @@ static CollSeq *multiSelectCollSeq(Parse *pParse, Select *p, int iCol){
 static int multiSelect(
   Parse *pParse,        /* Parsing context */
   Select *p,            /* The right-most of SELECTs to be coded */
-  SelectDest *pDest,    /* What to do with query results */
-  char *aff             /* If eDest is SRT_Union, the affinity string */
+  SelectDest *pDest     /* What to do with query results */
 ){
   int rc = SQLITE_OK;   /* Success code from a subroutine */
   Select *pPrior;       /* Another SELECT immediately to our left */
   Vdbe *v;              /* Generate code to this VDBE */
-  int nCol;             /* Number of columns in the result set */
-  ExprList *pOrderBy;   /* The ORDER BY clause on p */
-  int aSetP2[2];        /* Set P2 value of these op to number of columns */
-  int nSetP2 = 0;       /* Number of slots in aSetP2[] used */
   SelectDest dest;      /* Alternative data destination */
-
-  dest = *pDest;
+  Select *pDelete = 0;  /* Chain of simple selects to delete */
+  sqlite3 *db;          /* Database connection */
 
   /* Make sure there is no ORDER BY or LIMIT clause on prior SELECTs.  Only
   ** the last (right-most) SELECT in the series may have an ORDER BY or LIMIT.
   */
-  if( p==0 || p->pPrior==0 ){
-    rc = 1;
-    goto multi_select_end;
-  }
+  assert( p && p->pPrior );  /* Calling function guarantees this much */
+  db = pParse->db;
   pPrior = p->pPrior;
   assert( pPrior->pRightmost!=pPrior );
   assert( pPrior->pRightmost==p->pRightmost );
+  dest = *pDest;
   if( pPrior->pOrderBy ){
     sqlite3ErrorMsg(pParse,"ORDER BY clause should come after %s not before",
       selectOpName(p->op));
@@ -63298,57 +70353,65 @@ static int multiSelect(
     goto multi_select_end;
   }
 
-  /* Make sure we have a valid query engine.  If not, create a new one.
-  */
   v = sqlite3GetVdbe(pParse);
-  if( v==0 ){
-    rc = 1;
-    goto multi_select_end;
-  }
+  assert( v!=0 );  /* The VDBE already created by calling function */
 
   /* Create the destination temporary table if necessary
   */
   if( dest.eDest==SRT_EphemTab ){
     assert( p->pEList );
-    assert( nSetP2pEList->nExpr);
     dest.eDest = SRT_Table;
   }
 
+  /* Make sure all SELECTs in the statement have the same number of elements
+  ** in their result sets.
+  */
+  assert( p->pEList && pPrior->pEList );
+  if( p->pEList->nExpr!=pPrior->pEList->nExpr ){
+    sqlite3ErrorMsg(pParse, "SELECTs to the left and right of %s"
+      " do not have the same number of result columns", selectOpName(p->op));
+    rc = 1;
+    goto multi_select_end;
+  }
+
+  /* Compound SELECTs that have an ORDER BY clause are handled separately.
+  */
+  if( p->pOrderBy ){
+    return multiSelectOrderBy(pParse, p, pDest);
+  }
+
   /* Generate code for the left and right SELECT statements.
   */
-  pOrderBy = p->pOrderBy;
   switch( p->op ){
     case TK_ALL: {
-      if( pOrderBy==0 ){
-        int addr = 0;
-        assert( !pPrior->pLimit );
-        pPrior->pLimit = p->pLimit;
-        pPrior->pOffset = p->pOffset;
-        rc = sqlite3Select(pParse, pPrior, &dest, 0, 0, 0, aff);
-        p->pLimit = 0;
-        p->pOffset = 0;
-        if( rc ){
-          goto multi_select_end;
-        }
-        p->pPrior = 0;
-        p->iLimit = pPrior->iLimit;
-        p->iOffset = pPrior->iOffset;
-        if( p->iLimit>=0 ){
-          addr = sqlite3VdbeAddOp1(v, OP_IfZero, p->iLimit);
-          VdbeComment((v, "Jump ahead if LIMIT reached"));
-        }
-        rc = sqlite3Select(pParse, p, &dest, 0, 0, 0, aff);
-        p->pPrior = pPrior;
-        if( rc ){
-          goto multi_select_end;
-        }
-        if( addr ){
-          sqlite3VdbeJumpHere(v, addr);
-        }
-        break;
+      int addr = 0;
+      assert( !pPrior->pLimit );
+      pPrior->pLimit = p->pLimit;
+      pPrior->pOffset = p->pOffset;
+      rc = sqlite3Select(pParse, pPrior, &dest);
+      p->pLimit = 0;
+      p->pOffset = 0;
+      if( rc ){
+        goto multi_select_end;
+      }
+      p->pPrior = 0;
+      p->iLimit = pPrior->iLimit;
+      p->iOffset = pPrior->iOffset;
+      if( p->iLimit ){
+        addr = sqlite3VdbeAddOp1(v, OP_IfZero, p->iLimit);
+        VdbeComment((v, "Jump ahead if LIMIT reached"));
+      }
+      rc = sqlite3Select(pParse, p, &dest);
+      pDelete = p->pPrior;
+      p->pPrior = pPrior;
+      if( rc ){
+        goto multi_select_end;
+      }
+      if( addr ){
+        sqlite3VdbeJumpHere(v, addr);
       }
-      /* For UNION ALL ... ORDER BY fall through to the next case */
+      break;
     }
     case TK_EXCEPT:
     case TK_UNION: {
@@ -63359,8 +70422,8 @@ static int multiSelect(
       int addr;
       SelectDest uniondest;
 
-      priorOp = p->op==TK_ALL ? SRT_Table : SRT_Union;
-      if( dest.eDest==priorOp && pOrderBy==0 && !p->pLimit && !p->pOffset ){
+      priorOp = SRT_Union;
+      if( dest.eDest==priorOp && !p->pLimit && !p->pOffset ){
         /* We can reuse a temporary table generated by a SELECT to our
         ** right.
         */
@@ -63370,20 +70433,11 @@ static int multiSelect(
         ** intermediate results.
         */
         unionTab = pParse->nTab++;
-        if( processCompoundOrderBy(pParse, p, unionTab) ){
-          rc = 1;
-          goto multi_select_end;
-        }
+        assert( p->pOrderBy==0 );
         addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, unionTab, 0);
-        if( priorOp==SRT_Table ){
-          assert( nSetP2addrOpenEphm[0] == -1 );
-          p->addrOpenEphm[0] = addr;
-          p->pRightmost->usesEphm = 1;
-        }
-        createSortingIndex(pParse, p, pOrderBy);
+        assert( p->addrOpenEphm[0] == -1 );
+        p->addrOpenEphm[0] = addr;
+        p->pRightmost->selFlags |= SF_UsesEphemeral;
         assert( p->pEList );
       }
 
@@ -63391,37 +70445,37 @@ static int multiSelect(
       */
       assert( !pPrior->pOrderBy );
       sqlite3SelectDestInit(&uniondest, priorOp, unionTab);
-      rc = sqlite3Select(pParse, pPrior, &uniondest, 0, 0, 0, aff);
+      rc = sqlite3Select(pParse, pPrior, &uniondest);
       if( rc ){
         goto multi_select_end;
       }
 
       /* Code the current SELECT statement
       */
-      switch( p->op ){
-         case TK_EXCEPT:  op = SRT_Except;   break;
-         case TK_UNION:   op = SRT_Union;    break;
-         case TK_ALL:     op = SRT_Table;    break;
+      if( p->op==TK_EXCEPT ){
+        op = SRT_Except;
+      }else{
+        assert( p->op==TK_UNION );
+        op = SRT_Union;
       }
       p->pPrior = 0;
-      p->pOrderBy = 0;
-      p->disallowOrderBy = pOrderBy!=0;
       pLimit = p->pLimit;
       p->pLimit = 0;
       pOffset = p->pOffset;
       p->pOffset = 0;
       uniondest.eDest = op;
-      rc = sqlite3Select(pParse, p, &uniondest, 0, 0, 0, aff);
+      rc = sqlite3Select(pParse, p, &uniondest);
       /* Query flattening in sqlite3Select() might refill p->pOrderBy.
       ** Be sure to delete p->pOrderBy, therefore, to avoid a memory leak. */
-      sqlite3ExprListDelete(p->pOrderBy);
+      sqlite3ExprListDelete(db, p->pOrderBy);
+      pDelete = p->pPrior;
       p->pPrior = pPrior;
-      p->pOrderBy = pOrderBy;
-      sqlite3ExprDelete(p->pLimit);
+      p->pOrderBy = 0;
+      sqlite3ExprDelete(db, p->pLimit);
       p->pLimit = pLimit;
       p->pOffset = pOffset;
-      p->iLimit = -1;
-      p->iOffset = -1;
+      p->iLimit = 0;
+      p->iOffset = 0;
       if( rc ){
         goto multi_select_end;
       }
@@ -63433,7 +70487,7 @@ static int multiSelect(
       if( dest.eDest!=priorOp || unionTab!=dest.iParm ){
         int iCont, iBreak, iStart;
         assert( p->pEList );
-        if( dest.eDest==SRT_Callback ){
+        if( dest.eDest==SRT_Output ){
           Select *pFirst = p;
           while( pFirst->pPrior ) pFirst = pFirst->pPrior;
           generateColumnNames(pParse, 0, pFirst->pEList);
@@ -63444,7 +70498,7 @@ static int multiSelect(
         sqlite3VdbeAddOp2(v, OP_Rewind, unionTab, iBreak);
         iStart = sqlite3VdbeCurrentAddr(v);
         selectInnerLoop(pParse, p, p->pEList, unionTab, p->pEList->nExpr,
-                        pOrderBy, -1, &dest, iCont, iBreak, 0);
+                        0, -1, &dest, iCont, iBreak);
         sqlite3VdbeResolveLabel(v, iCont);
         sqlite3VdbeAddOp2(v, OP_Next, unionTab, iStart);
         sqlite3VdbeResolveLabel(v, iBreak);
@@ -63466,22 +70520,18 @@ static int multiSelect(
       */
       tab1 = pParse->nTab++;
       tab2 = pParse->nTab++;
-      if( processCompoundOrderBy(pParse, p, tab1) ){
-        rc = 1;
-        goto multi_select_end;
-      }
-      createSortingIndex(pParse, p, pOrderBy);
+      assert( p->pOrderBy==0 );
 
       addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, tab1, 0);
       assert( p->addrOpenEphm[0] == -1 );
       p->addrOpenEphm[0] = addr;
-      p->pRightmost->usesEphm = 1;
+      p->pRightmost->selFlags |= SF_UsesEphemeral;
       assert( p->pEList );
 
       /* Code the SELECTs to our left into temporary table "tab1".
       */
       sqlite3SelectDestInit(&intersectdest, SRT_Union, tab1);
-      rc = sqlite3Select(pParse, pPrior, &intersectdest, 0, 0, 0, aff);
+      rc = sqlite3Select(pParse, pPrior, &intersectdest);
       if( rc ){
         goto multi_select_end;
       }
@@ -63497,9 +70547,10 @@ static int multiSelect(
       pOffset = p->pOffset;
       p->pOffset = 0;
       intersectdest.iParm = tab2;
-      rc = sqlite3Select(pParse, p, &intersectdest, 0, 0, 0, aff);
+      rc = sqlite3Select(pParse, p, &intersectdest);
+      pDelete = p->pPrior;
       p->pPrior = pPrior;
-      sqlite3ExprDelete(p->pLimit);
+      sqlite3ExprDelete(db, p->pLimit);
       p->pLimit = pLimit;
       p->pOffset = pOffset;
       if( rc ){
@@ -63510,7 +70561,7 @@ static int multiSelect(
       ** tables.
       */
       assert( p->pEList );
-      if( dest.eDest==SRT_Callback ){
+      if( dest.eDest==SRT_Output ){
         Select *pFirst = p;
         while( pFirst->pPrior ) pFirst = pFirst->pPrior;
         generateColumnNames(pParse, 0, pFirst->pEList);
@@ -63524,7 +70575,7 @@ static int multiSelect(
       sqlite3VdbeAddOp3(v, OP_NotFound, tab2, iCont, r1);
       sqlite3ReleaseTempReg(pParse, r1);
       selectInnerLoop(pParse, p, p->pEList, tab1, p->pEList->nExpr,
-                      pOrderBy, -1, &dest, iCont, iBreak, 0);
+                      0, -1, &dest, iCont, iBreak);
       sqlite3VdbeResolveLabel(v, iCont);
       sqlite3VdbeAddOp2(v, OP_Next, tab1, iStart);
       sqlite3VdbeResolveLabel(v, iBreak);
@@ -63534,58 +70585,38 @@ static int multiSelect(
     }
   }
 
-  /* Make sure all SELECTs in the statement have the same number of elements
-  ** in their result sets.
-  */
-  assert( p->pEList && pPrior->pEList );
-  if( p->pEList->nExpr!=pPrior->pEList->nExpr ){
-    sqlite3ErrorMsg(pParse, "SELECTs to the left and right of %s"
-      " do not have the same number of result columns", selectOpName(p->op));
-    rc = 1;
-    goto multi_select_end;
-  }
-
-  /* Set the number of columns in temporary tables
-  */
-  nCol = p->pEList->nExpr;
-  while( nSetP2 ){
-    sqlite3VdbeChangeP2(v, aSetP2[--nSetP2], nCol);
-  }
-
-  /* Compute collating sequences used by either the ORDER BY clause or
-  ** by any temporary tables needed to implement the compound select.
-  ** Attach the KeyInfo structure to all temporary tables.  Invoke the
-  ** ORDER BY processing if there is an ORDER BY clause.
+  /* Compute collating sequences used by 
+  ** temporary tables needed to implement the compound select.
+  ** Attach the KeyInfo structure to all temporary tables.
   **
   ** This section is run by the right-most SELECT statement only.
   ** SELECT statements to the left always skip this part.  The right-most
   ** SELECT might also skip this part if it has no ORDER BY clause and
   ** no temp tables are required.
   */
-  if( pOrderBy || p->usesEphm ){
+  if( p->selFlags & SF_UsesEphemeral ){
     int i;                        /* Loop counter */
     KeyInfo *pKeyInfo;            /* Collating sequence for the result set */
     Select *pLoop;                /* For looping through SELECT statements */
-    int nKeyCol;                  /* Number of entries in pKeyInfo->aCol[] */
     CollSeq **apColl;             /* For looping through pKeyInfo->aColl[] */
-    CollSeq **aCopy;              /* A copy of pKeyInfo->aColl[] */
+    int nCol;                     /* Number of columns in result set */
 
     assert( p->pRightmost==p );
-    nKeyCol = nCol + (pOrderBy ? pOrderBy->nExpr : 0);
-    pKeyInfo = sqlite3DbMallocZero(pParse->db,
-                       sizeof(*pKeyInfo)+nKeyCol*(sizeof(CollSeq*) + 1));
+    nCol = p->pEList->nExpr;
+    pKeyInfo = sqlite3DbMallocZero(db,
+                       sizeof(*pKeyInfo)+nCol*(sizeof(CollSeq*) + 1));
     if( !pKeyInfo ){
       rc = SQLITE_NOMEM;
       goto multi_select_end;
     }
 
-    pKeyInfo->enc = ENC(pParse->db);
+    pKeyInfo->enc = ENC(db);
     pKeyInfo->nField = nCol;
 
     for(i=0, apColl=pKeyInfo->aColl; idb->pDfltColl;
+        *apColl = db->pDfltColl;
       }
     }
 
@@ -63603,146 +70634,702 @@ static int multiSelect(
         pLoop->addrOpenEphm[i] = -1;
       }
     }
-
-    if( pOrderBy ){
-      struct ExprList_item *pOTerm = pOrderBy->a;
-      int nOrderByExpr = pOrderBy->nExpr;
-      int addr;
-      u8 *pSortOrder;
-
-      /* Reuse the same pKeyInfo for the ORDER BY as was used above for
-      ** the compound select statements.  Except we have to change out the
-      ** pKeyInfo->aColl[] values.  Some of the aColl[] values will be
-      ** reused when constructing the pKeyInfo for the ORDER BY, so make
-      ** a copy.  Sufficient space to hold both the nCol entries for
-      ** the compound select and the nOrderbyExpr entries for the ORDER BY
-      ** was allocated above.  But we need to move the compound select
-      ** entries out of the way before constructing the ORDER BY entries.
-      ** Move the compound select entries into aCopy[] where they can be
-      ** accessed and reused when constructing the ORDER BY entries.
-      ** Because nCol might be greater than or less than nOrderByExpr
-      ** we have to use memmove() when doing the copy.
-      */
-      aCopy = &pKeyInfo->aColl[nOrderByExpr];
-      pSortOrder = pKeyInfo->aSortOrder = (u8*)&aCopy[nCol];
-      memmove(aCopy, pKeyInfo->aColl, nCol*sizeof(CollSeq*));
-
-      apColl = pKeyInfo->aColl;
-      for(i=0; ipExpr;
-        if( (pExpr->flags & EP_ExpCollate) ){
-          assert( pExpr->pColl!=0 );
-          *apColl = pExpr->pColl;
-        }else{
-          *apColl = aCopy[pExpr->iColumn];
-        }
-        *pSortOrder = pOTerm->sortOrder;
-      }
-      assert( p->pRightmost==p );
-      assert( p->addrOpenEphm[2]>=0 );
-      addr = p->addrOpenEphm[2];
-      sqlite3VdbeChangeP2(v, addr, p->pOrderBy->nExpr+2);
-      pKeyInfo->nField = nOrderByExpr;
-      sqlite3VdbeChangeP4(v, addr, (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
-      pKeyInfo = 0;
-      generateSortTail(pParse, p, v, p->pEList->nExpr, &dest);
-    }
-
-    sqlite3_free(pKeyInfo);
+    sqlite3DbFree(db, pKeyInfo);
   }
 
 multi_select_end:
   pDest->iMem = dest.iMem;
+  pDest->nMem = dest.nMem;
+  sqlite3SelectDelete(db, pDelete);
   return rc;
 }
 #endif /* SQLITE_OMIT_COMPOUND_SELECT */
 
-#ifndef SQLITE_OMIT_VIEW
-/* Forward Declarations */
-static void substExprList(sqlite3*, ExprList*, int, ExprList*);
-static void substSelect(sqlite3*, Select *, int, ExprList *);
-
 /*
-** Scan through the expression pExpr.  Replace every reference to
-** a column in table number iTable with a copy of the iColumn-th
-** entry in pEList.  (But leave references to the ROWID column 
-** unchanged.)
+** Code an output subroutine for a coroutine implementation of a
+** SELECT statment.
 **
-** This routine is part of the flattening procedure.  A subquery
-** whose result set is defined by pEList appears as entry in the
-** FROM clause of a SELECT such that the VDBE cursor assigned to that
-** FORM clause entry is iTable.  This routine make the necessary 
-** changes to pExpr so that it refers directly to the source table
-** of the subquery rather the result set of the subquery.
+** The data to be output is contained in pIn->iMem.  There are
+** pIn->nMem columns to be output.  pDest is where the output should
+** be sent.
+**
+** regReturn is the number of the register holding the subroutine
+** return address.
+**
+** If regPrev>0 then it is a the first register in a vector that
+** records the previous output.  mem[regPrev] is a flag that is false
+** if there has been no previous output.  If regPrev>0 then code is
+** generated to suppress duplicates.  pKeyInfo is used for comparing
+** keys.
+**
+** If the LIMIT found in p->iLimit is reached, jump immediately to
+** iBreak.
 */
-static void substExpr(
-  sqlite3 *db,        /* Report malloc errors to this connection */
-  Expr *pExpr,        /* Expr in which substitution occurs */
-  int iTable,         /* Table to be substituted */
-  ExprList *pEList    /* Substitute expressions */
-){
-  if( pExpr==0 ) return;
-  if( pExpr->op==TK_COLUMN && pExpr->iTable==iTable ){
-    if( pExpr->iColumn<0 ){
-      pExpr->op = TK_NULL;
-    }else{
-      Expr *pNew;
-      assert( pEList!=0 && pExpr->iColumnnExpr );
-      assert( pExpr->pLeft==0 && pExpr->pRight==0 && pExpr->pList==0 );
-      pNew = pEList->a[pExpr->iColumn].pExpr;
-      assert( pNew!=0 );
-      pExpr->op = pNew->op;
-      assert( pExpr->pLeft==0 );
-      pExpr->pLeft = sqlite3ExprDup(db, pNew->pLeft);
-      assert( pExpr->pRight==0 );
-      pExpr->pRight = sqlite3ExprDup(db, pNew->pRight);
-      assert( pExpr->pList==0 );
-      pExpr->pList = sqlite3ExprListDup(db, pNew->pList);
-      pExpr->iTable = pNew->iTable;
-      pExpr->pTab = pNew->pTab;
-      pExpr->iColumn = pNew->iColumn;
-      pExpr->iAgg = pNew->iAgg;
-      sqlite3TokenCopy(db, &pExpr->token, &pNew->token);
-      sqlite3TokenCopy(db, &pExpr->span, &pNew->span);
-      pExpr->pSelect = sqlite3SelectDup(db, pNew->pSelect);
-      pExpr->flags = pNew->flags;
-    }
-  }else{
-    substExpr(db, pExpr->pLeft, iTable, pEList);
-    substExpr(db, pExpr->pRight, iTable, pEList);
-    substSelect(db, pExpr->pSelect, iTable, pEList);
-    substExprList(db, pExpr->pList, iTable, pEList);
-  }
-}
-static void substExprList(
-  sqlite3 *db,         /* Report malloc errors here */
-  ExprList *pList,     /* List to scan and in which to make substitutes */
-  int iTable,          /* Table to be substituted */
-  ExprList *pEList     /* Substitute values */
-){
-  int i;
-  if( pList==0 ) return;
-  for(i=0; inExpr; i++){
-    substExpr(db, pList->a[i].pExpr, iTable, pEList);
-  }
-}
-static void substSelect(
-  sqlite3 *db,         /* Report malloc errors here */
-  Select *p,           /* SELECT statement in which to make substitutions */
-  int iTable,          /* Table to be replaced */
-  ExprList *pEList     /* Substitute values */
+static int generateOutputSubroutine(
+  Parse *pParse,          /* Parsing context */
+  Select *p,              /* The SELECT statement */
+  SelectDest *pIn,        /* Coroutine supplying data */
+  SelectDest *pDest,      /* Where to send the data */
+  int regReturn,          /* The return address register */
+  int regPrev,            /* Previous result register.  No uniqueness if 0 */
+  KeyInfo *pKeyInfo,      /* For comparing with previous entry */
+  int p4type,             /* The p4 type for pKeyInfo */
+  int iBreak              /* Jump here if we hit the LIMIT */
 ){
-  if( !p ) return;
-  substExprList(db, p->pEList, iTable, pEList);
-  substExprList(db, p->pGroupBy, iTable, pEList);
-  substExprList(db, p->pOrderBy, iTable, pEList);
-  substExpr(db, p->pHaving, iTable, pEList);
-  substExpr(db, p->pWhere, iTable, pEList);
-  substSelect(db, p->pPrior, iTable, pEList);
-}
-#endif /* !defined(SQLITE_OMIT_VIEW) */
+  Vdbe *v = pParse->pVdbe;
+  int iContinue;
+  int addr;
 
-#ifndef SQLITE_OMIT_VIEW
+  addr = sqlite3VdbeCurrentAddr(v);
+  iContinue = sqlite3VdbeMakeLabel(v);
+
+  /* Suppress duplicates for UNION, EXCEPT, and INTERSECT 
+  */
+  if( regPrev ){
+    int j1, j2;
+    j1 = sqlite3VdbeAddOp1(v, OP_IfNot, regPrev);
+    j2 = sqlite3VdbeAddOp4(v, OP_Compare, pIn->iMem, regPrev+1, pIn->nMem,
+                              (char*)pKeyInfo, p4type);
+    sqlite3VdbeAddOp3(v, OP_Jump, j2+2, iContinue, j2+2);
+    sqlite3VdbeJumpHere(v, j1);
+    sqlite3ExprCodeCopy(pParse, pIn->iMem, regPrev+1, pIn->nMem);
+    sqlite3VdbeAddOp2(v, OP_Integer, 1, regPrev);
+  }
+  if( pParse->db->mallocFailed ) return 0;
+
+  /* Suppress the the first OFFSET entries if there is an OFFSET clause
+  */
+  codeOffset(v, p, iContinue);
+
+  switch( pDest->eDest ){
+    /* Store the result as data using a unique key.
+    */
+    case SRT_Table:
+    case SRT_EphemTab: {
+      int r1 = sqlite3GetTempReg(pParse);
+      int r2 = sqlite3GetTempReg(pParse);
+      sqlite3VdbeAddOp3(v, OP_MakeRecord, pIn->iMem, pIn->nMem, r1);
+      sqlite3VdbeAddOp2(v, OP_NewRowid, pDest->iParm, r2);
+      sqlite3VdbeAddOp3(v, OP_Insert, pDest->iParm, r1, r2);
+      sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
+      sqlite3ReleaseTempReg(pParse, r2);
+      sqlite3ReleaseTempReg(pParse, r1);
+      break;
+    }
+
+#ifndef SQLITE_OMIT_SUBQUERY
+    /* If we are creating a set for an "expr IN (SELECT ...)" construct,
+    ** then there should be a single item on the stack.  Write this
+    ** item into the set table with bogus data.
+    */
+    case SRT_Set: {
+      int r1;
+      assert( pIn->nMem==1 );
+      p->affinity = 
+         sqlite3CompareAffinity(p->pEList->a[0].pExpr, pDest->affinity);
+      r1 = sqlite3GetTempReg(pParse);
+      sqlite3VdbeAddOp4(v, OP_MakeRecord, pIn->iMem, 1, r1, &p->affinity, 1);
+      sqlite3ExprCacheAffinityChange(pParse, pIn->iMem, 1);
+      sqlite3VdbeAddOp2(v, OP_IdxInsert, pDest->iParm, r1);
+      sqlite3ReleaseTempReg(pParse, r1);
+      break;
+    }
+
+#if 0  /* Never occurs on an ORDER BY query */
+    /* If any row exist in the result set, record that fact and abort.
+    */
+    case SRT_Exists: {
+      sqlite3VdbeAddOp2(v, OP_Integer, 1, pDest->iParm);
+      /* The LIMIT clause will terminate the loop for us */
+      break;
+    }
+#endif
+
+    /* If this is a scalar select that is part of an expression, then
+    ** store the results in the appropriate memory cell and break out
+    ** of the scan loop.
+    */
+    case SRT_Mem: {
+      assert( pIn->nMem==1 );
+      sqlite3ExprCodeMove(pParse, pIn->iMem, pDest->iParm, 1);
+      /* The LIMIT clause will jump out of the loop for us */
+      break;
+    }
+#endif /* #ifndef SQLITE_OMIT_SUBQUERY */
+
+    /* The results are stored in a sequence of registers
+    ** starting at pDest->iMem.  Then the co-routine yields.
+    */
+    case SRT_Coroutine: {
+      if( pDest->iMem==0 ){
+        pDest->iMem = sqlite3GetTempRange(pParse, pIn->nMem);
+        pDest->nMem = pIn->nMem;
+      }
+      sqlite3ExprCodeMove(pParse, pIn->iMem, pDest->iMem, pDest->nMem);
+      sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
+      break;
+    }
+
+    /* Results are stored in a sequence of registers.  Then the
+    ** OP_ResultRow opcode is used to cause sqlite3_step() to return
+    ** the next row of result.
+    */
+    case SRT_Output: {
+      sqlite3VdbeAddOp2(v, OP_ResultRow, pIn->iMem, pIn->nMem);
+      sqlite3ExprCacheAffinityChange(pParse, pIn->iMem, pIn->nMem);
+      break;
+    }
+
+#if !defined(SQLITE_OMIT_TRIGGER)
+    /* Discard the results.  This is used for SELECT statements inside
+    ** the body of a TRIGGER.  The purpose of such selects is to call
+    ** user-defined functions that have side effects.  We do not care
+    ** about the actual results of the select.
+    */
+    default: {
+      break;
+    }
+#endif
+  }
+
+  /* Jump to the end of the loop if the LIMIT is reached.
+  */
+  if( p->iLimit ){
+    sqlite3VdbeAddOp2(v, OP_AddImm, p->iLimit, -1);
+    sqlite3VdbeAddOp2(v, OP_IfZero, p->iLimit, iBreak);
+  }
+
+  /* Generate the subroutine return
+  */
+  sqlite3VdbeResolveLabel(v, iContinue);
+  sqlite3VdbeAddOp1(v, OP_Return, regReturn);
+
+  return addr;
+}
+
+/*
+** Alternative compound select code generator for cases when there
+** is an ORDER BY clause.
+**
+** We assume a query of the following form:
+**
+**            ORDER BY 
+**
+**  is one of UNION ALL, UNION, EXCEPT, or INTERSECT.  The idea
+** is to code both  and  with the ORDER BY clause as
+** co-routines.  Then run the co-routines in parallel and merge the results
+** into the output.  In addition to the two coroutines (called selectA and
+** selectB) there are 7 subroutines:
+**
+**    outA:    Move the output of the selectA coroutine into the output
+**             of the compound query.
+**
+**    outB:    Move the output of the selectB coroutine into the output
+**             of the compound query.  (Only generated for UNION and
+**             UNION ALL.  EXCEPT and INSERTSECT never output a row that
+**             appears only in B.)
+**
+**    AltB:    Called when there is data from both coroutines and AB.
+**
+**    EofA:    Called when data is exhausted from selectA.
+**
+**    EofB:    Called when data is exhausted from selectB.
+**
+** The implementation of the latter five subroutines depend on which 
+**  is used:
+**
+**
+**             UNION ALL         UNION            EXCEPT          INTERSECT
+**          -------------  -----------------  --------------  -----------------
+**   AltB:   outA, nextA      outA, nextA       outA, nextA         nextA
+**
+**   AeqB:   outA, nextA         nextA             nextA         outA, nextA
+**
+**   AgtB:   outB, nextB      outB, nextB          nextB            nextB
+**
+**   EofA:   outB, nextB      outB, nextB          halt             halt
+**
+**   EofB:   outA, nextA      outA, nextA       outA, nextA         halt
+**
+** In the AltB, AeqB, and AgtB subroutines, an EOF on A following nextA
+** causes an immediate jump to EofA and an EOF on B following nextB causes
+** an immediate jump to EofB.  Within EofA and EofB, and EOF on entry or
+** following nextX causes a jump to the end of the select processing.
+**
+** Duplicate removal in the UNION, EXCEPT, and INTERSECT cases is handled
+** within the output subroutine.  The regPrev register set holds the previously
+** output value.  A comparison is made against this value and the output
+** is skipped if the next results would be the same as the previous.
+**
+** The implementation plan is to implement the two coroutines and seven
+** subroutines first, then put the control logic at the bottom.  Like this:
+**
+**          goto Init
+**     coA: coroutine for left query (A)
+**     coB: coroutine for right query (B)
+**    outA: output one row of A
+**    outB: output one row of B (UNION and UNION ALL only)
+**    EofA: ...
+**    EofB: ...
+**    AltB: ...
+**    AeqB: ...
+**    AgtB: ...
+**    Init: initialize coroutine registers
+**          yield coA
+**          if eof(A) goto EofA
+**          yield coB
+**          if eof(B) goto EofB
+**    Cmpr: Compare A, B
+**          Jump AltB, AeqB, AgtB
+**     End: ...
+**
+** We call AltB, AeqB, AgtB, EofA, and EofB "subroutines" but they are not
+** actually called using Gosub and they do not Return.  EofA and EofB loop
+** until all data is exhausted then jump to the "end" labe.  AltB, AeqB,
+** and AgtB jump to either L2 or to one of EofA or EofB.
+*/
+#ifndef SQLITE_OMIT_COMPOUND_SELECT
+static int multiSelectOrderBy(
+  Parse *pParse,        /* Parsing context */
+  Select *p,            /* The right-most of SELECTs to be coded */
+  SelectDest *pDest     /* What to do with query results */
+){
+  int i, j;             /* Loop counters */
+  Select *pPrior;       /* Another SELECT immediately to our left */
+  Vdbe *v;              /* Generate code to this VDBE */
+  SelectDest destA;     /* Destination for coroutine A */
+  SelectDest destB;     /* Destination for coroutine B */
+  int regAddrA;         /* Address register for select-A coroutine */
+  int regEofA;          /* Flag to indicate when select-A is complete */
+  int regAddrB;         /* Address register for select-B coroutine */
+  int regEofB;          /* Flag to indicate when select-B is complete */
+  int addrSelectA;      /* Address of the select-A coroutine */
+  int addrSelectB;      /* Address of the select-B coroutine */
+  int regOutA;          /* Address register for the output-A subroutine */
+  int regOutB;          /* Address register for the output-B subroutine */
+  int addrOutA;         /* Address of the output-A subroutine */
+  int addrOutB;         /* Address of the output-B subroutine */
+  int addrEofA;         /* Address of the select-A-exhausted subroutine */
+  int addrEofB;         /* Address of the select-B-exhausted subroutine */
+  int addrAltB;         /* Address of the AB subroutine */
+  int regLimitA;        /* Limit register for select-A */
+  int regLimitB;        /* Limit register for select-A */
+  int regPrev;          /* A range of registers to hold previous output */
+  int savedLimit;       /* Saved value of p->iLimit */
+  int savedOffset;      /* Saved value of p->iOffset */
+  int labelCmpr;        /* Label for the start of the merge algorithm */
+  int labelEnd;         /* Label for the end of the overall SELECT stmt */
+  int j1;               /* Jump instructions that get retargetted */
+  int op;               /* One of TK_ALL, TK_UNION, TK_EXCEPT, TK_INTERSECT */
+  KeyInfo *pKeyDup = 0; /* Comparison information for duplicate removal */
+  KeyInfo *pKeyMerge;   /* Comparison information for merging rows */
+  sqlite3 *db;          /* Database connection */
+  ExprList *pOrderBy;   /* The ORDER BY clause */
+  int nOrderBy;         /* Number of terms in the ORDER BY clause */
+  int *aPermute;        /* Mapping from ORDER BY terms to result set columns */
+
+  assert( p->pOrderBy!=0 );
+  assert( pKeyDup==0 ); /* "Managed" code needs this.  Ticket #3382. */
+  db = pParse->db;
+  v = pParse->pVdbe;
+  if( v==0 ) return SQLITE_NOMEM;
+  labelEnd = sqlite3VdbeMakeLabel(v);
+  labelCmpr = sqlite3VdbeMakeLabel(v);
+
+
+  /* Patch up the ORDER BY clause
+  */
+  op = p->op;  
+  pPrior = p->pPrior;
+  assert( pPrior->pOrderBy==0 );
+  pOrderBy = p->pOrderBy;
+  assert( pOrderBy );
+  nOrderBy = pOrderBy->nExpr;
+
+  /* For operators other than UNION ALL we have to make sure that
+  ** the ORDER BY clause covers every term of the result set.  Add
+  ** terms to the ORDER BY clause as necessary.
+  */
+  if( op!=TK_ALL ){
+    for(i=1; db->mallocFailed==0 && i<=p->pEList->nExpr; i++){
+      struct ExprList_item *pItem;
+      for(j=0, pItem=pOrderBy->a; jiCol>0 );
+        if( pItem->iCol==i ) break;
+      }
+      if( j==nOrderBy ){
+        Expr *pNew = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, 0);
+        if( pNew==0 ) return SQLITE_NOMEM;
+        pNew->flags |= EP_IntValue;
+        pNew->iTable = i;
+        pOrderBy = sqlite3ExprListAppend(pParse, pOrderBy, pNew, 0);
+        pOrderBy->a[nOrderBy++].iCol = i;
+      }
+    }
+  }
+
+  /* Compute the comparison permutation and keyinfo that is used with
+  ** the permutation in order to comparisons to determine if the next
+  ** row of results comes from selectA or selectB.  Also add explicit
+  ** collations to the ORDER BY clause terms so that when the subqueries
+  ** to the right and the left are evaluated, they use the correct
+  ** collation.
+  */
+  aPermute = sqlite3DbMallocRaw(db, sizeof(int)*nOrderBy);
+  if( aPermute ){
+    struct ExprList_item *pItem;
+    for(i=0, pItem=pOrderBy->a; iiCol>0  && pItem->iCol<=p->pEList->nExpr );
+      aPermute[i] = pItem->iCol - 1;
+    }
+    pKeyMerge =
+      sqlite3DbMallocRaw(db, sizeof(*pKeyMerge)+nOrderBy*(sizeof(CollSeq*)+1));
+    if( pKeyMerge ){
+      pKeyMerge->aSortOrder = (u8*)&pKeyMerge->aColl[nOrderBy];
+      pKeyMerge->nField = nOrderBy;
+      pKeyMerge->enc = ENC(db);
+      for(i=0; ia[i].pExpr;
+        if( pTerm->flags & EP_ExpCollate ){
+          pColl = pTerm->pColl;
+        }else{
+          pColl = multiSelectCollSeq(pParse, p, aPermute[i]);
+          pTerm->flags |= EP_ExpCollate;
+          pTerm->pColl = pColl;
+        }
+        pKeyMerge->aColl[i] = pColl;
+        pKeyMerge->aSortOrder[i] = pOrderBy->a[i].sortOrder;
+      }
+    }
+  }else{
+    pKeyMerge = 0;
+  }
+
+  /* Reattach the ORDER BY clause to the query.
+  */
+  p->pOrderBy = pOrderBy;
+  pPrior->pOrderBy = sqlite3ExprListDup(pParse->db, pOrderBy);
+
+  /* Allocate a range of temporary registers and the KeyInfo needed
+  ** for the logic that removes duplicate result rows when the
+  ** operator is UNION, EXCEPT, or INTERSECT (but not UNION ALL).
+  */
+  if( op==TK_ALL ){
+    regPrev = 0;
+  }else{
+    int nExpr = p->pEList->nExpr;
+    assert( nOrderBy>=nExpr );
+    regPrev = sqlite3GetTempRange(pParse, nExpr+1);
+    sqlite3VdbeAddOp2(v, OP_Integer, 0, regPrev);
+    pKeyDup = sqlite3DbMallocZero(db,
+                  sizeof(*pKeyDup) + nExpr*(sizeof(CollSeq*)+1) );
+    if( pKeyDup ){
+      pKeyDup->aSortOrder = (u8*)&pKeyDup->aColl[nExpr];
+      pKeyDup->nField = nExpr;
+      pKeyDup->enc = ENC(db);
+      for(i=0; iaColl[i] = multiSelectCollSeq(pParse, p, i);
+        pKeyDup->aSortOrder[i] = 0;
+      }
+    }
+  }
+ 
+  /* Separate the left and the right query from one another
+  */
+  p->pPrior = 0;
+  pPrior->pRightmost = 0;
+  sqlite3ResolveOrderGroupBy(pParse, p, p->pOrderBy, "ORDER");
+  if( pPrior->pPrior==0 ){
+    sqlite3ResolveOrderGroupBy(pParse, pPrior, pPrior->pOrderBy, "ORDER");
+  }
+
+  /* Compute the limit registers */
+  computeLimitRegisters(pParse, p, labelEnd);
+  if( p->iLimit && op==TK_ALL ){
+    regLimitA = ++pParse->nMem;
+    regLimitB = ++pParse->nMem;
+    sqlite3VdbeAddOp2(v, OP_Copy, p->iOffset ? p->iOffset+1 : p->iLimit,
+                                  regLimitA);
+    sqlite3VdbeAddOp2(v, OP_Copy, regLimitA, regLimitB);
+  }else{
+    regLimitA = regLimitB = 0;
+  }
+  sqlite3ExprDelete(db, p->pLimit);
+  p->pLimit = 0;
+  sqlite3ExprDelete(db, p->pOffset);
+  p->pOffset = 0;
+
+  regAddrA = ++pParse->nMem;
+  regEofA = ++pParse->nMem;
+  regAddrB = ++pParse->nMem;
+  regEofB = ++pParse->nMem;
+  regOutA = ++pParse->nMem;
+  regOutB = ++pParse->nMem;
+  sqlite3SelectDestInit(&destA, SRT_Coroutine, regAddrA);
+  sqlite3SelectDestInit(&destB, SRT_Coroutine, regAddrB);
+
+  /* Jump past the various subroutines and coroutines to the main
+  ** merge loop
+  */
+  j1 = sqlite3VdbeAddOp0(v, OP_Goto);
+  addrSelectA = sqlite3VdbeCurrentAddr(v);
+
+
+  /* Generate a coroutine to evaluate the SELECT statement to the
+  ** left of the compound operator - the "A" select.
+  */
+  VdbeNoopComment((v, "Begin coroutine for left SELECT"));
+  pPrior->iLimit = regLimitA;
+  sqlite3Select(pParse, pPrior, &destA);
+  sqlite3VdbeAddOp2(v, OP_Integer, 1, regEofA);
+  sqlite3VdbeAddOp1(v, OP_Yield, regAddrA);
+  VdbeNoopComment((v, "End coroutine for left SELECT"));
+
+  /* Generate a coroutine to evaluate the SELECT statement on 
+  ** the right - the "B" select
+  */
+  addrSelectB = sqlite3VdbeCurrentAddr(v);
+  VdbeNoopComment((v, "Begin coroutine for right SELECT"));
+  savedLimit = p->iLimit;
+  savedOffset = p->iOffset;
+  p->iLimit = regLimitB;
+  p->iOffset = 0;  
+  sqlite3Select(pParse, p, &destB);
+  p->iLimit = savedLimit;
+  p->iOffset = savedOffset;
+  sqlite3VdbeAddOp2(v, OP_Integer, 1, regEofB);
+  sqlite3VdbeAddOp1(v, OP_Yield, regAddrB);
+  VdbeNoopComment((v, "End coroutine for right SELECT"));
+
+  /* Generate a subroutine that outputs the current row of the A
+  ** select as the next output row of the compound select.
+  */
+  VdbeNoopComment((v, "Output routine for A"));
+  addrOutA = generateOutputSubroutine(pParse,
+                 p, &destA, pDest, regOutA,
+                 regPrev, pKeyDup, P4_KEYINFO_HANDOFF, labelEnd);
+  
+  /* Generate a subroutine that outputs the current row of the B
+  ** select as the next output row of the compound select.
+  */
+  if( op==TK_ALL || op==TK_UNION ){
+    VdbeNoopComment((v, "Output routine for B"));
+    addrOutB = generateOutputSubroutine(pParse,
+                 p, &destB, pDest, regOutB,
+                 regPrev, pKeyDup, P4_KEYINFO_STATIC, labelEnd);
+  }
+
+  /* Generate a subroutine to run when the results from select A
+  ** are exhausted and only data in select B remains.
+  */
+  VdbeNoopComment((v, "eof-A subroutine"));
+  if( op==TK_EXCEPT || op==TK_INTERSECT ){
+    addrEofA = sqlite3VdbeAddOp2(v, OP_Goto, 0, labelEnd);
+  }else{  
+    addrEofA = sqlite3VdbeAddOp2(v, OP_If, regEofB, labelEnd);
+    sqlite3VdbeAddOp2(v, OP_Gosub, regOutB, addrOutB);
+    sqlite3VdbeAddOp1(v, OP_Yield, regAddrB);
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrEofA);
+  }
+
+  /* Generate a subroutine to run when the results from select B
+  ** are exhausted and only data in select A remains.
+  */
+  if( op==TK_INTERSECT ){
+    addrEofB = addrEofA;
+  }else{  
+    VdbeNoopComment((v, "eof-B subroutine"));
+    addrEofB = sqlite3VdbeAddOp2(v, OP_If, regEofA, labelEnd);
+    sqlite3VdbeAddOp2(v, OP_Gosub, regOutA, addrOutA);
+    sqlite3VdbeAddOp1(v, OP_Yield, regAddrA);
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrEofB);
+  }
+
+  /* Generate code to handle the case of AB
+  */
+  VdbeNoopComment((v, "A-gt-B subroutine"));
+  addrAgtB = sqlite3VdbeCurrentAddr(v);
+  if( op==TK_ALL || op==TK_UNION ){
+    sqlite3VdbeAddOp2(v, OP_Gosub, regOutB, addrOutB);
+  }
+  sqlite3VdbeAddOp1(v, OP_Yield, regAddrB);
+  sqlite3VdbeAddOp2(v, OP_If, regEofB, addrEofB);
+  sqlite3VdbeAddOp2(v, OP_Goto, 0, labelCmpr);
+
+  /* This code runs once to initialize everything.
+  */
+  sqlite3VdbeJumpHere(v, j1);
+  sqlite3VdbeAddOp2(v, OP_Integer, 0, regEofA);
+  sqlite3VdbeAddOp2(v, OP_Integer, 0, regEofB);
+  sqlite3VdbeAddOp2(v, OP_Gosub, regAddrA, addrSelectA);
+  sqlite3VdbeAddOp2(v, OP_Gosub, regAddrB, addrSelectB);
+  sqlite3VdbeAddOp2(v, OP_If, regEofA, addrEofA);
+  sqlite3VdbeAddOp2(v, OP_If, regEofB, addrEofB);
+
+  /* Implement the main merge loop
+  */
+  sqlite3VdbeResolveLabel(v, labelCmpr);
+  sqlite3VdbeAddOp4(v, OP_Permutation, 0, 0, 0, (char*)aPermute, P4_INTARRAY);
+  sqlite3VdbeAddOp4(v, OP_Compare, destA.iMem, destB.iMem, nOrderBy,
+                         (char*)pKeyMerge, P4_KEYINFO_HANDOFF);
+  sqlite3VdbeAddOp3(v, OP_Jump, addrAltB, addrAeqB, addrAgtB);
+
+  /* Release temporary registers
+  */
+  if( regPrev ){
+    sqlite3ReleaseTempRange(pParse, regPrev, nOrderBy+1);
+  }
+
+  /* Jump to the this point in order to terminate the query.
+  */
+  sqlite3VdbeResolveLabel(v, labelEnd);
+
+  /* Set the number of output columns
+  */
+  if( pDest->eDest==SRT_Output ){
+    Select *pFirst = pPrior;
+    while( pFirst->pPrior ) pFirst = pFirst->pPrior;
+    generateColumnNames(pParse, 0, pFirst->pEList);
+  }
+
+  /* Reassembly the compound query so that it will be freed correctly
+  ** by the calling function */
+  if( p->pPrior ){
+    sqlite3SelectDelete(db, p->pPrior);
+  }
+  p->pPrior = pPrior;
+
+  /*** TBD:  Insert subroutine calls to close cursors on incomplete
+  **** subqueries ****/
+  return SQLITE_OK;
+}
+#endif
+
+#if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW)
+/* Forward Declarations */
+static void substExprList(sqlite3*, ExprList*, int, ExprList*);
+static void substSelect(sqlite3*, Select *, int, ExprList *);
+
+/*
+** Scan through the expression pExpr.  Replace every reference to
+** a column in table number iTable with a copy of the iColumn-th
+** entry in pEList.  (But leave references to the ROWID column 
+** unchanged.)
+**
+** This routine is part of the flattening procedure.  A subquery
+** whose result set is defined by pEList appears as entry in the
+** FROM clause of a SELECT such that the VDBE cursor assigned to that
+** FORM clause entry is iTable.  This routine make the necessary 
+** changes to pExpr so that it refers directly to the source table
+** of the subquery rather the result set of the subquery.
+*/
+static void substExpr(
+  sqlite3 *db,        /* Report malloc errors to this connection */
+  Expr *pExpr,        /* Expr in which substitution occurs */
+  int iTable,         /* Table to be substituted */
+  ExprList *pEList    /* Substitute expressions */
+){
+  if( pExpr==0 ) return;
+  if( pExpr->op==TK_COLUMN && pExpr->iTable==iTable ){
+    if( pExpr->iColumn<0 ){
+      pExpr->op = TK_NULL;
+    }else{
+      Expr *pNew;
+      assert( pEList!=0 && pExpr->iColumnnExpr );
+      assert( pExpr->pLeft==0 && pExpr->pRight==0 && pExpr->pList==0 );
+      pNew = pEList->a[pExpr->iColumn].pExpr;
+      assert( pNew!=0 );
+      pExpr->op = pNew->op;
+      assert( pExpr->pLeft==0 );
+      pExpr->pLeft = sqlite3ExprDup(db, pNew->pLeft);
+      assert( pExpr->pRight==0 );
+      pExpr->pRight = sqlite3ExprDup(db, pNew->pRight);
+      assert( pExpr->pList==0 );
+      pExpr->pList = sqlite3ExprListDup(db, pNew->pList);
+      pExpr->iTable = pNew->iTable;
+      pExpr->pTab = pNew->pTab;
+      pExpr->iColumn = pNew->iColumn;
+      pExpr->iAgg = pNew->iAgg;
+      sqlite3TokenCopy(db, &pExpr->token, &pNew->token);
+      sqlite3TokenCopy(db, &pExpr->span, &pNew->span);
+      pExpr->pSelect = sqlite3SelectDup(db, pNew->pSelect);
+      pExpr->flags = pNew->flags;
+    }
+  }else{
+    substExpr(db, pExpr->pLeft, iTable, pEList);
+    substExpr(db, pExpr->pRight, iTable, pEList);
+    substSelect(db, pExpr->pSelect, iTable, pEList);
+    substExprList(db, pExpr->pList, iTable, pEList);
+  }
+}
+static void substExprList(
+  sqlite3 *db,         /* Report malloc errors here */
+  ExprList *pList,     /* List to scan and in which to make substitutes */
+  int iTable,          /* Table to be substituted */
+  ExprList *pEList     /* Substitute values */
+){
+  int i;
+  if( pList==0 ) return;
+  for(i=0; inExpr; i++){
+    substExpr(db, pList->a[i].pExpr, iTable, pEList);
+  }
+}
+static void substSelect(
+  sqlite3 *db,         /* Report malloc errors here */
+  Select *p,           /* SELECT statement in which to make substitutions */
+  int iTable,          /* Table to be replaced */
+  ExprList *pEList     /* Substitute values */
+){
+  SrcList *pSrc;
+  struct SrcList_item *pItem;
+  int i;
+  if( !p ) return;
+  substExprList(db, p->pEList, iTable, pEList);
+  substExprList(db, p->pGroupBy, iTable, pEList);
+  substExprList(db, p->pOrderBy, iTable, pEList);
+  substExpr(db, p->pHaving, iTable, pEList);
+  substExpr(db, p->pWhere, iTable, pEList);
+  substSelect(db, p->pPrior, iTable, pEList);
+  pSrc = p->pSrc;
+  if( pSrc ){
+    for(i=pSrc->nSrc, pItem=pSrc->a; i>0; i--, pItem++){
+      substSelect(db, pItem->pSelect, iTable, pEList);
+    }
+  }
+}
+#endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */
+
+#if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW)
 /*
 ** This routine attempts to flatten subqueries in order to speed
 ** execution.  It returns 1 if it makes changes and 0 if no flattening
@@ -63776,8 +71363,8 @@ static void substSelect(
 **
 **   (2)  The subquery is not an aggregate or the outer query is not a join.
 **
-**   (3)  The subquery is not the right operand of a left outer join, or
-**        the subquery is not itself a join.  (Ticket #306)
+**   (3)  The subquery is not the right operand of a left outer join
+**        (Originally ticket #306.  Strenghtened by ticket #3300)
 **
 **   (4)  The subquery is not DISTINCT or the outer query is not a join.
 **
@@ -63799,8 +71386,8 @@ static void substSelect(
 **
 **  (11)  The subquery and the outer query do not both have ORDER BY clauses.
 **
-**  (12)  The subquery is not the right term of a LEFT OUTER JOIN or the
-**        subquery has no WHERE clause.  (added by ticket #350)
+**  (12)  Not implemented.  Subsumed into restriction (3).  Was previously
+**        a separate restriction deriving from ticket #350.
 **
 **  (13)  The subquery and outer query do not both use LIMIT
 **
@@ -63814,6 +71401,25 @@ static void substSelect(
 **        not contain ORDER BY.  (Ticket #2942)  This used to not matter
 **        until we introduced the group_concat() function.  
 **
+**  (17)  The sub-query is not a compound select, or it is a UNION ALL 
+**        compound clause made up entirely of non-aggregate queries, and 
+**        the parent query:
+**
+**          * is not itself part of a compound select,
+**          * is not an aggregate or DISTINCT query, and
+**          * has no other tables or sub-selects in the FROM clause.
+**
+**        The parent and sub-query may contain WHERE clauses. Subject to
+**        rules (11), (13) and (14), they may also contain ORDER BY,
+**        LIMIT and OFFSET clauses.
+**
+**  (18)  If the sub-query is a compound select, then all terms of the
+**        ORDER by clause of the parent must be simple references to 
+**        columns of the sub-query.
+**
+**  (19)  The subquery does not use LIMIT or the outer query does not
+**        have a WHERE clause.
+**
 ** In this routine, the "p" parameter is a pointer to the outer query.
 ** The subquery is p->pSrc->a[iFrom].  isAgg is true if the outer query
 ** uses aggregates and subqueryIsAgg is true if the subquery uses aggregates.
@@ -63825,13 +71431,16 @@ static void substSelect(
 ** the subquery before this routine runs.
 */
 static int flattenSubquery(
-  sqlite3 *db,         /* Database connection */
+  Parse *pParse,       /* Parsing context */
   Select *p,           /* The parent or outer SELECT statement */
   int iFrom,           /* Index in p->pSrc->a[] of the inner subquery */
   int isAgg,           /* True if outer SELECT uses aggregate functions */
   int subqueryIsAgg    /* True if the subquery uses aggregate functions */
 ){
+  const char *zSavedAuthContext = pParse->zAuthContext;
+  Select *pParent;
   Select *pSub;       /* The inner query or "subquery" */
+  Select *pSub1;      /* Pointer to the rightmost select in sub-query */
   SrcList *pSrc;      /* The FROM clause of the outer query */
   SrcList *pSubSrc;   /* The FROM clause of the subquery */
   ExprList *pList;    /* The result set of the outer query */
@@ -63839,6 +71448,7 @@ static int flattenSubquery(
   int i;              /* Loop counter */
   Expr *pWhere;                    /* The WHERE clause */
   struct SrcList_item *pSubitem;   /* The subquery */
+  sqlite3 *db = pParse->db;
 
   /* Check to see if flattening is permitted.  Return 0 if not.
   */
@@ -63846,6 +71456,7 @@ static int flattenSubquery(
   pSrc = p->pSrc;
   assert( pSrc && iFrom>=0 && iFromnSrc );
   pSubitem = &pSrc->a[iFrom];
+  iParent = pSubitem->iCursor;
   pSub = pSubitem->pSelect;
   assert( pSub!=0 );
   if( isAgg && subqueryIsAgg ) return 0;                 /* Restriction (1)  */
@@ -63863,17 +71474,21 @@ static int flattenSubquery(
     return 0;                                            /* Restriction (15) */
   }
   if( pSubSrc->nSrc==0 ) return 0;                       /* Restriction (7)  */
-  if( (pSub->isDistinct || pSub->pLimit) 
+  if( ((pSub->selFlags & SF_Distinct)!=0 || pSub->pLimit) 
          && (pSrc->nSrc>1 || isAgg) ){          /* Restrictions (4)(5)(8)(9) */
      return 0;       
   }
-  if( p->isDistinct && subqueryIsAgg ) return 0;         /* Restriction (6)  */
-  if( (p->disallowOrderBy || p->pOrderBy) && pSub->pOrderBy ){
+  if( (p->selFlags & SF_Distinct)!=0 && subqueryIsAgg ){
+     return 0;         /* Restriction (6)  */
+  }
+  if( p->pOrderBy && pSub->pOrderBy ){
      return 0;                                           /* Restriction (11) */
   }
   if( isAgg && pSub->pOrderBy ) return 0;                /* Restriction (16) */
+  if( pSub->pLimit && p->pWhere ) return 0;              /* Restriction (19) */
 
-  /* Restriction 3:  If the subquery is a join, make sure the subquery is 
+  /* OBSOLETE COMMENT 1:
+  ** Restriction 3:  If the subquery is a join, make sure the subquery is 
   ** not used as the right operand of an outer join.  Examples of why this
   ** is not allowed:
   **
@@ -63884,12 +71499,9 @@ static int flattenSubquery(
   **         (t1 LEFT OUTER JOIN t2) JOIN t3
   **
   ** which is not at all the same thing.
-  */
-  if( pSubSrc->nSrc>1 && (pSubitem->jointype & JT_OUTER)!=0 ){
-    return 0;
-  }
-
-  /* Restriction 12:  If the subquery is the right operand of a left outer
+  **
+  ** OBSOLETE COMMENT 2:
+  ** Restriction 12:  If the subquery is the right operand of a left outer
   ** join, make sure the subquery has no WHERE clause.
   ** An examples of why this is not allowed:
   **
@@ -63901,46 +71513,139 @@ static int flattenSubquery(
   **
   ** But the t2.x>0 test will always fail on a NULL row of t2, which
   ** effectively converts the OUTER JOIN into an INNER JOIN.
+  **
+  ** THIS OVERRIDES OBSOLETE COMMENTS 1 AND 2 ABOVE:
+  ** Ticket #3300 shows that flattening the right term of a LEFT JOIN
+  ** is fraught with danger.  Best to avoid the whole thing.  If the
+  ** subquery is the right term of a LEFT JOIN, then do not flatten.
   */
-  if( (pSubitem->jointype & JT_OUTER)!=0 && pSub->pWhere!=0 ){
+  if( (pSubitem->jointype & JT_OUTER)!=0 ){
     return 0;
   }
 
-  /* If we reach this point, it means flattening is permitted for the
-  ** iFrom-th entry of the FROM clause in the outer query.
+  /* Restriction 17: If the sub-query is a compound SELECT, then it must
+  ** use only the UNION ALL operator. And none of the simple select queries
+  ** that make up the compound SELECT are allowed to be aggregate or distinct
+  ** queries.
   */
+  if( pSub->pPrior ){
+    if( p->pPrior || isAgg || (p->selFlags & SF_Distinct)!=0 || pSrc->nSrc!=1 ){
+      return 0;
+    }
+    for(pSub1=pSub; pSub1; pSub1=pSub1->pPrior){
+      if( (pSub1->selFlags & (SF_Distinct|SF_Aggregate))!=0
+       || (pSub1->pPrior && pSub1->op!=TK_ALL) 
+       || !pSub1->pSrc || pSub1->pSrc->nSrc!=1
+      ){
+        return 0;
+      }
+    }
 
-  /* Move all of the FROM elements of the subquery into the
-  ** the FROM clause of the outer query.  Before doing this, remember
-  ** the cursor number for the original outer query FROM element in
-  ** iParent.  The iParent cursor will never be used.  Subsequent code
-  ** will scan expressions looking for iParent references and replace
-  ** those references with expressions that resolve to the subquery FROM
-  ** elements we are now copying in.
-  */
-  iParent = pSubitem->iCursor;
-  {
+    /* Restriction 18. */
+    if( p->pOrderBy ){
+      int ii;
+      for(ii=0; iipOrderBy->nExpr; ii++){
+        if( p->pOrderBy->a[ii].iCol==0 ) return 0;
+      }
+    }
+  }
+
+  /***** If we reach this point, flattening is permitted. *****/
+
+  /* Authorize the subquery */
+  pParse->zAuthContext = pSubitem->zName;
+  sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0);
+  pParse->zAuthContext = zSavedAuthContext;
+
+  /* If the sub-query is a compound SELECT statement, then (by restrictions
+  ** 17 and 18 above) it must be a UNION ALL and the parent query must 
+  ** be of the form:
+  **
+  **     SELECT  FROM ()  
+  **
+  ** followed by any ORDER BY, LIMIT and/or OFFSET clauses. This block
+  ** creates N copies of the parent query without any ORDER BY, LIMIT or 
+  ** OFFSET clauses and joins them to the left-hand-side of the original
+  ** using UNION ALL operators. In this case N is the number of simple
+  ** select statements in the compound sub-query.
+  */
+  for(pSub=pSub->pPrior; pSub; pSub=pSub->pPrior){
+    Select *pNew;
+    ExprList *pOrderBy = p->pOrderBy;
+    Expr *pLimit = p->pLimit;
+    Expr *pOffset = p->pOffset;
+    Select *pPrior = p->pPrior;
+    p->pOrderBy = 0;
+    p->pSrc = 0;
+    p->pPrior = 0;
+    p->pLimit = 0;
+    pNew = sqlite3SelectDup(db, p);
+    pNew->pPrior = pPrior;
+    p->pPrior = pNew;
+    p->pOrderBy = pOrderBy;
+    p->op = TK_ALL;
+    p->pSrc = pSrc;
+    p->pLimit = pLimit;
+    p->pOffset = pOffset;
+    p->pRightmost = 0;
+    pNew->pRightmost = 0;
+  }
+
+  /* Begin flattening the iFrom-th entry of the FROM clause 
+  ** in the outer query.
+  */
+  pSub = pSub1 = pSubitem->pSelect;
+  for(pParent=p; pParent; pParent=pParent->pPrior, pSub=pSub->pPrior){
     int nSubSrc = pSubSrc->nSrc;
-    int jointype = pSubitem->jointype;
-
-    sqlite3DeleteTable(pSubitem->pTab);
-    sqlite3_free(pSubitem->zDatabase);
-    sqlite3_free(pSubitem->zName);
-    sqlite3_free(pSubitem->zAlias);
-    pSubitem->pTab = 0;
-    pSubitem->zDatabase = 0;
-    pSubitem->zName = 0;
-    pSubitem->zAlias = 0;
-    if( nSubSrc>1 ){
+    int jointype = 0;
+    pSubSrc = pSub->pSrc;
+    pSrc = pParent->pSrc;
+
+    /* Move all of the FROM elements of the subquery into the
+    ** the FROM clause of the outer query.  Before doing this, remember
+    ** the cursor number for the original outer query FROM element in
+    ** iParent.  The iParent cursor will never be used.  Subsequent code
+    ** will scan expressions looking for iParent references and replace
+    ** those references with expressions that resolve to the subquery FROM
+    ** elements we are now copying in.
+    */
+    if( pSrc ){
+      Table *pTabToDel;
+      pSubitem = &pSrc->a[iFrom];
+      nSubSrc = pSubSrc->nSrc;
+      jointype = pSubitem->jointype;
+      sqlite3DbFree(db, pSubitem->zDatabase);
+      sqlite3DbFree(db, pSubitem->zName);
+      sqlite3DbFree(db, pSubitem->zAlias);
+      pSubitem->zDatabase = 0;
+      pSubitem->zName = 0;
+      pSubitem->zAlias = 0;
+
+      /* If the FROM element is a subquery, defer deleting the Table
+      ** object associated with that subquery until code generation is
+      ** complete, since there may still exist Expr.pTab entires that
+      ** refer to the subquery even after flattening.  Ticket #3346.
+      */
+      if( (pTabToDel = pSubitem->pTab)!=0 ){
+        if( pTabToDel->nRef==1 ){
+          pTabToDel->pNextZombie = pParse->pZombieTab;
+          pParse->pZombieTab = pTabToDel;
+        }else{
+          pTabToDel->nRef--;
+        }
+      }
+      pSubitem->pTab = 0;
+    }
+    if( nSubSrc!=1 || !pSrc ){
       int extra = nSubSrc - 1;
-      for(i=1; ipSrc = 0;
+          pParent->pSrc = 0;
           return 1;
         }
       }
-      p->pSrc = pSrc;
+      pParent->pSrc = pSrc;
       for(i=pSrc->nSrc-1; i-extra>=iFrom; i--){
         pSrc->a[i] = pSrc->a[i-extra];
       }
@@ -63950,86 +71655,87 @@ static int flattenSubquery(
       memset(&pSubSrc->a[i], 0, sizeof(pSubSrc->a[i]));
     }
     pSrc->a[iFrom].jointype = jointype;
-  }
-
-  /* Now begin substituting subquery result set expressions for 
-  ** references to the iParent in the outer query.
-  ** 
-  ** Example:
-  **
-  **   SELECT a+5, b*10 FROM (SELECT x*3 AS a, y+10 AS b FROM t1) WHERE a>b;
-  **   \                     \_____________ subquery __________/          /
-  **    \_____________________ outer query ______________________________/
-  **
-  ** We look at every expression in the outer query and every place we see
-  ** "a" we substitute "x*3" and every place we see "b" we substitute "y+10".
-  */
-  pList = p->pEList;
-  for(i=0; inExpr; i++){
-    Expr *pExpr;
-    if( pList->a[i].zName==0 && (pExpr = pList->a[i].pExpr)->span.z!=0 ){
-      pList->a[i].zName = 
-             sqlite3DbStrNDup(db, (char*)pExpr->span.z, pExpr->span.n);
+  
+    /* Now begin substituting subquery result set expressions for 
+    ** references to the iParent in the outer query.
+    ** 
+    ** Example:
+    **
+    **   SELECT a+5, b*10 FROM (SELECT x*3 AS a, y+10 AS b FROM t1) WHERE a>b;
+    **   \                     \_____________ subquery __________/          /
+    **    \_____________________ outer query ______________________________/
+    **
+    ** We look at every expression in the outer query and every place we see
+    ** "a" we substitute "x*3" and every place we see "b" we substitute "y+10".
+    */
+    pList = pParent->pEList;
+    for(i=0; inExpr; i++){
+      Expr *pExpr;
+      if( pList->a[i].zName==0 && (pExpr = pList->a[i].pExpr)->span.z!=0 ){
+        pList->a[i].zName = 
+               sqlite3DbStrNDup(db, (char*)pExpr->span.z, pExpr->span.n);
+      }
+    }
+    substExprList(db, pParent->pEList, iParent, pSub->pEList);
+    if( isAgg ){
+      substExprList(db, pParent->pGroupBy, iParent, pSub->pEList);
+      substExpr(db, pParent->pHaving, iParent, pSub->pEList);
+    }
+    if( pSub->pOrderBy ){
+      assert( pParent->pOrderBy==0 );
+      pParent->pOrderBy = pSub->pOrderBy;
+      pSub->pOrderBy = 0;
+    }else if( pParent->pOrderBy ){
+      substExprList(db, pParent->pOrderBy, iParent, pSub->pEList);
+    }
+    if( pSub->pWhere ){
+      pWhere = sqlite3ExprDup(db, pSub->pWhere);
+    }else{
+      pWhere = 0;
+    }
+    if( subqueryIsAgg ){
+      assert( pParent->pHaving==0 );
+      pParent->pHaving = pParent->pWhere;
+      pParent->pWhere = pWhere;
+      substExpr(db, pParent->pHaving, iParent, pSub->pEList);
+      pParent->pHaving = sqlite3ExprAnd(db, pParent->pHaving, 
+                                  sqlite3ExprDup(db, pSub->pHaving));
+      assert( pParent->pGroupBy==0 );
+      pParent->pGroupBy = sqlite3ExprListDup(db, pSub->pGroupBy);
+    }else{
+      substExpr(db, pParent->pWhere, iParent, pSub->pEList);
+      pParent->pWhere = sqlite3ExprAnd(db, pParent->pWhere, pWhere);
+    }
+  
+    /* The flattened query is distinct if either the inner or the
+    ** outer query is distinct. 
+    */
+    pParent->selFlags |= pSub->selFlags & SF_Distinct;
+  
+    /*
+    ** SELECT ... FROM (SELECT ... LIMIT a OFFSET b) LIMIT x OFFSET y;
+    **
+    ** One is tempted to try to add a and b to combine the limits.  But this
+    ** does not work if either limit is negative.
+    */
+    if( pSub->pLimit ){
+      pParent->pLimit = pSub->pLimit;
+      pSub->pLimit = 0;
     }
-  }
-  substExprList(db, p->pEList, iParent, pSub->pEList);
-  if( isAgg ){
-    substExprList(db, p->pGroupBy, iParent, pSub->pEList);
-    substExpr(db, p->pHaving, iParent, pSub->pEList);
-  }
-  if( pSub->pOrderBy ){
-    assert( p->pOrderBy==0 );
-    p->pOrderBy = pSub->pOrderBy;
-    pSub->pOrderBy = 0;
-  }else if( p->pOrderBy ){
-    substExprList(db, p->pOrderBy, iParent, pSub->pEList);
-  }
-  if( pSub->pWhere ){
-    pWhere = sqlite3ExprDup(db, pSub->pWhere);
-  }else{
-    pWhere = 0;
-  }
-  if( subqueryIsAgg ){
-    assert( p->pHaving==0 );
-    p->pHaving = p->pWhere;
-    p->pWhere = pWhere;
-    substExpr(db, p->pHaving, iParent, pSub->pEList);
-    p->pHaving = sqlite3ExprAnd(db, p->pHaving, 
-                                sqlite3ExprDup(db, pSub->pHaving));
-    assert( p->pGroupBy==0 );
-    p->pGroupBy = sqlite3ExprListDup(db, pSub->pGroupBy);
-  }else{
-    substExpr(db, p->pWhere, iParent, pSub->pEList);
-    p->pWhere = sqlite3ExprAnd(db, p->pWhere, pWhere);
-  }
-
-  /* The flattened query is distinct if either the inner or the
-  ** outer query is distinct. 
-  */
-  p->isDistinct = p->isDistinct || pSub->isDistinct;
-
-  /*
-  ** SELECT ... FROM (SELECT ... LIMIT a OFFSET b) LIMIT x OFFSET y;
-  **
-  ** One is tempted to try to add a and b to combine the limits.  But this
-  ** does not work if either limit is negative.
-  */
-  if( pSub->pLimit ){
-    p->pLimit = pSub->pLimit;
-    pSub->pLimit = 0;
   }
 
   /* Finially, delete what is left of the subquery and return
   ** success.
   */
-  sqlite3SelectDelete(pSub);
+  sqlite3SelectDelete(db, pSub1);
+
   return 1;
 }
-#endif /* SQLITE_OMIT_VIEW */
+#endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */
 
 /*
 ** Analyze the SELECT statement passed as an argument to see if it
-** is a min() or max() query. Return ORDERBY_MIN or ORDERBY_MAX if 
+** is a min() or max() query. Return WHERE_ORDERBY_MIN or WHERE_ORDERBY_MAX if 
 ** it is, or 0 otherwise. At present, a query is considered to be
 ** a min()/max() query if:
 **
@@ -64042,171 +71748,437 @@ static int minMaxQuery(Parse *pParse, Select *p){
   Expr *pExpr;
   ExprList *pEList = p->pEList;
 
-  if( pEList->nExpr!=1 ) return ORDERBY_NORMAL;
+  if( pEList->nExpr!=1 ) return WHERE_ORDERBY_NORMAL;
   pExpr = pEList->a[0].pExpr;
   pEList = pExpr->pList;
   if( pExpr->op!=TK_AGG_FUNCTION || pEList==0 || pEList->nExpr!=1 ) return 0;
-  if( pEList->a[0].pExpr->op!=TK_AGG_COLUMN ) return ORDERBY_NORMAL;
-  if( pExpr->token.n!=3 ) return ORDERBY_NORMAL;
+  if( pEList->a[0].pExpr->op!=TK_AGG_COLUMN ) return WHERE_ORDERBY_NORMAL;
+  if( pExpr->token.n!=3 ) return WHERE_ORDERBY_NORMAL;
   if( sqlite3StrNICmp((char*)pExpr->token.z,"min",3)==0 ){
-    return ORDERBY_MIN;
+    return WHERE_ORDERBY_MIN;
   }else if( sqlite3StrNICmp((char*)pExpr->token.z,"max",3)==0 ){
-    return ORDERBY_MAX;
+    return WHERE_ORDERBY_MAX;
   }
-  return ORDERBY_NORMAL;
+  return WHERE_ORDERBY_NORMAL;
 }
 
 /*
-** This routine resolves any names used in the result set of the
-** supplied SELECT statement. If the SELECT statement being resolved
-** is a sub-select, then pOuterNC is a pointer to the NameContext 
-** of the parent SELECT.
+** If the source-list item passed as an argument was augmented with an
+** INDEXED BY clause, then try to locate the specified index. If there
+** was such a clause and the named index cannot be found, return 
+** SQLITE_ERROR and leave an error in pParse. Otherwise, populate 
+** pFrom->pIndex and return SQLITE_OK.
 */
-SQLITE_PRIVATE int sqlite3SelectResolve(
-  Parse *pParse,         /* The parser context */
-  Select *p,             /* The SELECT statement being coded. */
-  NameContext *pOuterNC  /* The outer name context. May be NULL. */
-){
-  ExprList *pEList;          /* Result set. */
-  int i;                     /* For-loop variable used in multiple places */
-  NameContext sNC;           /* Local name-context */
-  ExprList *pGroupBy;        /* The group by clause */
-
-  /* If this routine has run before, return immediately. */
-  if( p->isResolved ){
-    assert( !pOuterNC );
-    return SQLITE_OK;
+SQLITE_PRIVATE int sqlite3IndexedByLookup(Parse *pParse, struct SrcList_item *pFrom){
+  if( pFrom->pTab && pFrom->zIndex ){
+    Table *pTab = pFrom->pTab;
+    char *zIndex = pFrom->zIndex;
+    Index *pIdx;
+    for(pIdx=pTab->pIndex; 
+        pIdx && sqlite3StrICmp(pIdx->zName, zIndex); 
+        pIdx=pIdx->pNext
+    );
+    if( !pIdx ){
+      sqlite3ErrorMsg(pParse, "no such index: %s", zIndex, 0);
+      return SQLITE_ERROR;
+    }
+    pFrom->pIndex = pIdx;
   }
-  p->isResolved = 1;
+  return SQLITE_OK;
+}
 
-  /* If there have already been errors, do nothing. */
-  if( pParse->nErr>0 ){
-    return SQLITE_ERROR;
-  }
+/*
+** This routine is a Walker callback for "expanding" a SELECT statement.
+** "Expanding" means to do the following:
+**
+**    (1)  Make sure VDBE cursor numbers have been assigned to every
+**         element of the FROM clause.
+**
+**    (2)  Fill in the pTabList->a[].pTab fields in the SrcList that 
+**         defines FROM clause.  When views appear in the FROM clause,
+**         fill pTabList->a[].pSelect with a copy of the SELECT statement
+**         that implements the view.  A copy is made of the view's SELECT
+**         statement so that we can freely modify or delete that statement
+**         without worrying about messing up the presistent representation
+**         of the view.
+**
+**    (3)  Add terms to the WHERE clause to accomodate the NATURAL keyword
+**         on joins and the ON and USING clause of joins.
+**
+**    (4)  Scan the list of columns in the result set (pEList) looking
+**         for instances of the "*" operator or the TABLE.* operator.
+**         If found, expand each "*" to be every column in every table
+**         and TABLE.* to be every column in TABLE.
+**
+*/
+static int selectExpander(Walker *pWalker, Select *p){
+  Parse *pParse = pWalker->pParse;
+  int i, j, k;
+  SrcList *pTabList;
+  ExprList *pEList;
+  struct SrcList_item *pFrom;
+  sqlite3 *db = pParse->db;
 
-  /* Prepare the select statement. This call will allocate all cursors
-  ** required to handle the tables and subqueries in the FROM clause.
-  */
-  if( prepSelectStmt(pParse, p) ){
-    return SQLITE_ERROR;
+  if( db->mallocFailed  ){
+    return WRC_Abort;
   }
-
-  /* Resolve the expressions in the LIMIT and OFFSET clauses. These
-  ** are not allowed to refer to any names, so pass an empty NameContext.
-  */
-  memset(&sNC, 0, sizeof(sNC));
-  sNC.pParse = pParse;
-  if( sqlite3ExprResolveNames(&sNC, p->pLimit) ||
-      sqlite3ExprResolveNames(&sNC, p->pOffset) ){
-    return SQLITE_ERROR;
+  if( p->pSrc==0 || (p->selFlags & SF_Expanded)!=0 ){
+    return WRC_Prune;
   }
-
-  /* Set up the local name-context to pass to ExprResolveNames() to
-  ** resolve the expression-list.
-  */
-  sNC.allowAgg = 1;
-  sNC.pSrcList = p->pSrc;
-  sNC.pNext = pOuterNC;
-
-  /* Resolve names in the result set. */
+  p->selFlags |= SF_Expanded;
+  pTabList = p->pSrc;
   pEList = p->pEList;
-  if( !pEList ) return SQLITE_ERROR;
-  for(i=0; inExpr; i++){
-    Expr *pX = pEList->a[i].pExpr;
-    if( sqlite3ExprResolveNames(&sNC, pX) ){
-      return SQLITE_ERROR;
-    }
-  }
 
-  /* If there are no aggregate functions in the result-set, and no GROUP BY 
-  ** expression, do not allow aggregates in any of the other expressions.
+  /* Make sure cursor numbers have been assigned to all entries in
+  ** the FROM clause of the SELECT statement.
   */
-  assert( !p->isAgg );
-  pGroupBy = p->pGroupBy;
-  if( pGroupBy || sNC.hasAgg ){
-    p->isAgg = 1;
-  }else{
-    sNC.allowAgg = 0;
-  }
+  sqlite3SrcListAssignCursors(pParse, pTabList);
 
-  /* If a HAVING clause is present, then there must be a GROUP BY clause.
+  /* Look up every table named in the FROM clause of the select.  If
+  ** an entry of the FROM clause is a subquery instead of a table or view,
+  ** then create a transient table structure to describe the subquery.
   */
-  if( p->pHaving && !pGroupBy ){
-    sqlite3ErrorMsg(pParse, "a GROUP BY clause is required before HAVING");
-    return SQLITE_ERROR;
-  }
+  for(i=0, pFrom=pTabList->a; inSrc; i++, pFrom++){
+    Table *pTab;
+    if( pFrom->pTab!=0 ){
+      /* This statement has already been prepared.  There is no need
+      ** to go further. */
+      assert( i==0 );
+      return WRC_Prune;
+    }
+    if( pFrom->zName==0 ){
+#ifndef SQLITE_OMIT_SUBQUERY
+      Select *pSel = pFrom->pSelect;
+      /* A sub-query in the FROM clause of a SELECT */
+      assert( pSel!=0 );
+      assert( pFrom->pTab==0 );
+      sqlite3WalkSelect(pWalker, pSel);
+      pFrom->pTab = pTab = sqlite3DbMallocZero(db, sizeof(Table));
+      if( pTab==0 ) return WRC_Abort;
+      pTab->db = db;
+      pTab->nRef = 1;
+      pTab->zName = sqlite3MPrintf(db, "sqlite_subquery_%p_", (void*)pTab);
+      while( pSel->pPrior ){ pSel = pSel->pPrior; }
+      selectColumnsFromExprList(pParse, pSel->pEList, &pTab->nCol, &pTab->aCol);
+      pTab->iPKey = -1;
+      pTab->tabFlags |= TF_Ephemeral;
+#endif
+    }else{
+      /* An ordinary table or view name in the FROM clause */
+      assert( pFrom->pTab==0 );
+      pFrom->pTab = pTab = 
+        sqlite3LocateTable(pParse,0,pFrom->zName,pFrom->zDatabase);
+      if( pTab==0 ) return WRC_Abort;
+      pTab->nRef++;
+#if !defined(SQLITE_OMIT_VIEW) || !defined (SQLITE_OMIT_VIRTUALTABLE)
+      if( pTab->pSelect || IsVirtual(pTab) ){
+        /* We reach here if the named table is a really a view */
+        if( sqlite3ViewGetColumnNames(pParse, pTab) ) return WRC_Abort;
 
-  /* Add the expression list to the name-context before parsing the
-  ** other expressions in the SELECT statement. This is so that
-  ** expressions in the WHERE clause (etc.) can refer to expressions by
-  ** aliases in the result set.
-  **
-  ** Minor point: If this is the case, then the expression will be
-  ** re-evaluated for each reference to it.
-  */
-  sNC.pEList = p->pEList;
-  if( sqlite3ExprResolveNames(&sNC, p->pWhere) ||
-     sqlite3ExprResolveNames(&sNC, p->pHaving) ){
-    return SQLITE_ERROR;
-  }
-  if( p->pPrior==0 ){
-    if( processOrderGroupBy(pParse, p, p->pOrderBy, 1, &sNC.hasAgg) ){
-      return SQLITE_ERROR;
+        /* If pFrom->pSelect!=0 it means we are dealing with a
+        ** view within a view.  The SELECT structure has already been
+        ** copied by the outer view so we can skip the copy step here
+        ** in the inner view.
+        */
+        if( pFrom->pSelect==0 ){
+          pFrom->pSelect = sqlite3SelectDup(db, pTab->pSelect);
+          sqlite3WalkSelect(pWalker, pFrom->pSelect);
+        }
+      }
+#endif
     }
-  }
-  if( processOrderGroupBy(pParse, p, pGroupBy, 0, &sNC.hasAgg) ){
-    return SQLITE_ERROR;
-  }
 
-  if( pParse->db->mallocFailed ){
-    return SQLITE_NOMEM;
+    /* Locate the index named by the INDEXED BY clause, if any. */
+    if( sqlite3IndexedByLookup(pParse, pFrom) ){
+      return WRC_Abort;
+    }
   }
 
-  /* Make sure the GROUP BY clause does not contain aggregate functions.
+  /* Process NATURAL keywords, and ON and USING clauses of joins.
   */
-  if( pGroupBy ){
-    struct ExprList_item *pItem;
-  
-    for(i=0, pItem=pGroupBy->a; inExpr; i++, pItem++){
-      if( ExprHasProperty(pItem->pExpr, EP_Agg) ){
-        sqlite3ErrorMsg(pParse, "aggregate functions are not allowed in "
-            "the GROUP BY clause");
-        return SQLITE_ERROR;
-      }
-    }
+  if( db->mallocFailed || sqliteProcessJoin(pParse, p) ){
+    return WRC_Abort;
   }
 
-  /* If this is one SELECT of a compound, be sure to resolve names
-  ** in the other SELECTs.
+  /* For every "*" that occurs in the column list, insert the names of
+  ** all columns in all tables.  And for every TABLE.* insert the names
+  ** of all columns in TABLE.  The parser inserted a special expression
+  ** with the TK_ALL operator for each "*" that it found in the column list.
+  ** The following code just has to locate the TK_ALL expressions and expand
+  ** each one to the list of all columns in all tables.
+  **
+  ** The first loop just checks to see if there are any "*" operators
+  ** that need expanding.
   */
-  if( p->pPrior ){
-    return sqlite3SelectResolve(pParse, p->pPrior, pOuterNC);
-  }else{
-    return SQLITE_OK;
+  for(k=0; knExpr; k++){
+    Expr *pE = pEList->a[k].pExpr;
+    if( pE->op==TK_ALL ) break;
+    if( pE->op==TK_DOT && pE->pRight && pE->pRight->op==TK_ALL
+         && pE->pLeft && pE->pLeft->op==TK_ID ) break;
   }
-}
+  if( knExpr ){
+    /*
+    ** If we get here it means the result set contains one or more "*"
+    ** operators that need to be expanded.  Loop through each expression
+    ** in the result set and expand them one by one.
+    */
+    struct ExprList_item *a = pEList->a;
+    ExprList *pNew = 0;
+    int flags = pParse->db->flags;
+    int longNames = (flags & SQLITE_FullColNames)!=0
+                      && (flags & SQLITE_ShortColNames)==0;
 
-/*
-** Reset the aggregate accumulator.
-**
-** The aggregate accumulator is a set of memory cells that hold
-** intermediate results while calculating an aggregate.  This
-** routine simply stores NULLs in all of those memory cells.
-*/
-static void resetAccumulator(Parse *pParse, AggInfo *pAggInfo){
-  Vdbe *v = pParse->pVdbe;
-  int i;
-  struct AggInfo_func *pFunc;
-  if( pAggInfo->nFunc+pAggInfo->nColumn==0 ){
-    return;
-  }
-  for(i=0; inColumn; i++){
-    sqlite3VdbeAddOp2(v, OP_Null, 0, pAggInfo->aCol[i].iMem);
-  }
-  for(pFunc=pAggInfo->aFunc, i=0; inFunc; i++, pFunc++){
-    sqlite3VdbeAddOp2(v, OP_Null, 0, pFunc->iMem);
-    if( pFunc->iDistinct>=0 ){
-      Expr *pE = pFunc->pExpr;
+    for(k=0; knExpr; k++){
+      Expr *pE = a[k].pExpr;
+      if( pE->op!=TK_ALL &&
+           (pE->op!=TK_DOT || pE->pRight==0 || pE->pRight->op!=TK_ALL) ){
+        /* This particular expression does not need to be expanded.
+        */
+        pNew = sqlite3ExprListAppend(pParse, pNew, a[k].pExpr, 0);
+        if( pNew ){
+          pNew->a[pNew->nExpr-1].zName = a[k].zName;
+        }
+        a[k].pExpr = 0;
+        a[k].zName = 0;
+      }else{
+        /* This expression is a "*" or a "TABLE.*" and needs to be
+        ** expanded. */
+        int tableSeen = 0;      /* Set to 1 when TABLE matches */
+        char *zTName;            /* text of name of TABLE */
+        if( pE->op==TK_DOT && pE->pLeft ){
+          zTName = sqlite3NameFromToken(db, &pE->pLeft->token);
+        }else{
+          zTName = 0;
+        }
+        for(i=0, pFrom=pTabList->a; inSrc; i++, pFrom++){
+          Table *pTab = pFrom->pTab;
+          char *zTabName = pFrom->zAlias;
+          if( zTabName==0 || zTabName[0]==0 ){ 
+            zTabName = pTab->zName;
+          }
+          if( db->mallocFailed ) break;
+          if( zTName && sqlite3StrICmp(zTName, zTabName)!=0 ){
+            continue;
+          }
+          tableSeen = 1;
+          for(j=0; jnCol; j++){
+            Expr *pExpr, *pRight;
+            char *zName = pTab->aCol[j].zName;
+
+            /* If a column is marked as 'hidden' (currently only possible
+            ** for virtual tables), do not include it in the expanded
+            ** result-set list.
+            */
+            if( IsHiddenColumn(&pTab->aCol[j]) ){
+              assert(IsVirtual(pTab));
+              continue;
+            }
+
+            if( i>0 ){
+              struct SrcList_item *pLeft = &pTabList->a[i-1];
+              if( (pLeft[1].jointype & JT_NATURAL)!=0 &&
+                        columnIndex(pLeft->pTab, zName)>=0 ){
+                /* In a NATURAL join, omit the join columns from the 
+                ** table on the right */
+                continue;
+              }
+              if( sqlite3IdListIndex(pLeft[1].pUsing, zName)>=0 ){
+                /* In a join with a USING clause, omit columns in the
+                ** using clause from the table on the right. */
+                continue;
+              }
+            }
+            pRight = sqlite3PExpr(pParse, TK_ID, 0, 0, 0);
+            if( pRight==0 ) break;
+            setQuotedToken(pParse, &pRight->token, zName);
+            if( longNames || pTabList->nSrc>1 ){
+              Expr *pLeft = sqlite3PExpr(pParse, TK_ID, 0, 0, 0);
+              pExpr = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight, 0);
+              if( pExpr==0 ) break;
+              setQuotedToken(pParse, &pLeft->token, zTabName);
+              setToken(&pExpr->span, 
+                  sqlite3MPrintf(db, "%s.%s", zTabName, zName));
+              pExpr->span.dyn = 1;
+              pExpr->token.z = 0;
+              pExpr->token.n = 0;
+              pExpr->token.dyn = 0;
+            }else{
+              pExpr = pRight;
+              pExpr->span = pExpr->token;
+              pExpr->span.dyn = 0;
+            }
+            if( longNames ){
+              pNew = sqlite3ExprListAppend(pParse, pNew, pExpr, &pExpr->span);
+            }else{
+              pNew = sqlite3ExprListAppend(pParse, pNew, pExpr, &pRight->token);
+            }
+          }
+        }
+        if( !tableSeen ){
+          if( zTName ){
+            sqlite3ErrorMsg(pParse, "no such table: %s", zTName);
+          }else{
+            sqlite3ErrorMsg(pParse, "no tables specified");
+          }
+        }
+        sqlite3DbFree(db, zTName);
+      }
+    }
+    sqlite3ExprListDelete(db, pEList);
+    p->pEList = pNew;
+  }
+#if SQLITE_MAX_COLUMN
+  if( p->pEList && p->pEList->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){
+    sqlite3ErrorMsg(pParse, "too many columns in result set");
+  }
+#endif
+  return WRC_Continue;
+}
+
+/*
+** No-op routine for the parse-tree walker.
+**
+** When this routine is the Walker.xExprCallback then expression trees
+** are walked without any actions being taken at each node.  Presumably,
+** when this routine is used for Walker.xExprCallback then 
+** Walker.xSelectCallback is set to do something useful for every 
+** subquery in the parser tree.
+*/
+static int exprWalkNoop(Walker *pWalker, Expr *pExpr){
+  return WRC_Continue;
+}
+
+/*
+** This routine "expands" a SELECT statement and all of its subqueries.
+** For additional information on what it means to "expand" a SELECT
+** statement, see the comment on the selectExpand worker callback above.
+**
+** Expanding a SELECT statement is the first step in processing a
+** SELECT statement.  The SELECT statement must be expanded before
+** name resolution is performed.
+**
+** If anything goes wrong, an error message is written into pParse.
+** The calling function can detect the problem by looking at pParse->nErr
+** and/or pParse->db->mallocFailed.
+*/
+static void sqlite3SelectExpand(Parse *pParse, Select *pSelect){
+  Walker w;
+  w.xSelectCallback = selectExpander;
+  w.xExprCallback = exprWalkNoop;
+  w.pParse = pParse;
+  sqlite3WalkSelect(&w, pSelect);
+}
+
+
+#ifndef SQLITE_OMIT_SUBQUERY
+/*
+** This is a Walker.xSelectCallback callback for the sqlite3SelectTypeInfo()
+** interface.
+**
+** For each FROM-clause subquery, add Column.zType and Column.zColl
+** information to the Table structure that represents the result set
+** of that subquery.
+**
+** The Table structure that represents the result set was constructed
+** by selectExpander() but the type and collation information was omitted
+** at that point because identifiers had not yet been resolved.  This
+** routine is called after identifier resolution.
+*/
+static int selectAddSubqueryTypeInfo(Walker *pWalker, Select *p){
+  Parse *pParse;
+  int i;
+  SrcList *pTabList;
+  struct SrcList_item *pFrom;
+
+  assert( p->selFlags & SF_Resolved );
+  if( (p->selFlags & SF_HasTypeInfo)==0 ){
+    p->selFlags |= SF_HasTypeInfo;
+    pParse = pWalker->pParse;
+    pTabList = p->pSrc;
+    for(i=0, pFrom=pTabList->a; inSrc; i++, pFrom++){
+      Table *pTab = pFrom->pTab;
+      if( pTab && (pTab->tabFlags & TF_Ephemeral)!=0 ){
+        /* A sub-query in the FROM clause of a SELECT */
+        Select *pSel = pFrom->pSelect;
+        assert( pSel );
+        while( pSel->pPrior ) pSel = pSel->pPrior;
+        selectAddColumnTypeAndCollation(pParse, pTab->nCol, pTab->aCol, pSel);
+      }
+    }
+  }
+  return WRC_Continue;
+}
+#endif
+
+
+/*
+** This routine adds datatype and collating sequence information to
+** the Table structures of all FROM-clause subqueries in a
+** SELECT statement.
+**
+** Use this routine after name resolution.
+*/
+static void sqlite3SelectAddTypeInfo(Parse *pParse, Select *pSelect){
+#ifndef SQLITE_OMIT_SUBQUERY
+  Walker w;
+  w.xSelectCallback = selectAddSubqueryTypeInfo;
+  w.xExprCallback = exprWalkNoop;
+  w.pParse = pParse;
+  sqlite3WalkSelect(&w, pSelect);
+#endif
+}
+
+
+/*
+** This routine sets of a SELECT statement for processing.  The
+** following is accomplished:
+**
+**     *  VDBE Cursor numbers are assigned to all FROM-clause terms.
+**     *  Ephemeral Table objects are created for all FROM-clause subqueries.
+**     *  ON and USING clauses are shifted into WHERE statements
+**     *  Wildcards "*" and "TABLE.*" in result sets are expanded.
+**     *  Identifiers in expression are matched to tables.
+**
+** This routine acts recursively on all subqueries within the SELECT.
+*/
+SQLITE_PRIVATE void sqlite3SelectPrep(
+  Parse *pParse,         /* The parser context */
+  Select *p,             /* The SELECT statement being coded. */
+  NameContext *pOuterNC  /* Name context for container */
+){
+  sqlite3 *db;
+  if( p==0 ) return;
+  db = pParse->db;
+  if( p->selFlags & SF_HasTypeInfo ) return;
+  if( pParse->nErr || db->mallocFailed ) return;
+  sqlite3SelectExpand(pParse, p);
+  if( pParse->nErr || db->mallocFailed ) return;
+  sqlite3ResolveSelectNames(pParse, p, pOuterNC);
+  if( pParse->nErr || db->mallocFailed ) return;
+  sqlite3SelectAddTypeInfo(pParse, p);
+}
+
+/*
+** Reset the aggregate accumulator.
+**
+** The aggregate accumulator is a set of memory cells that hold
+** intermediate results while calculating an aggregate.  This
+** routine simply stores NULLs in all of those memory cells.
+*/
+static void resetAccumulator(Parse *pParse, AggInfo *pAggInfo){
+  Vdbe *v = pParse->pVdbe;
+  int i;
+  struct AggInfo_func *pFunc;
+  if( pAggInfo->nFunc+pAggInfo->nColumn==0 ){
+    return;
+  }
+  for(i=0; inColumn; i++){
+    sqlite3VdbeAddOp2(v, OP_Null, 0, pAggInfo->aCol[i].iMem);
+  }
+  for(pFunc=pAggInfo->aFunc, i=0; inFunc; i++, pFunc++){
+    sqlite3VdbeAddOp2(v, OP_Null, 0, pFunc->iMem);
+    if( pFunc->iDistinct>=0 ){
+      Expr *pE = pFunc->pExpr;
       if( pE->pList==0 || pE->pList->nExpr!=1 ){
         sqlite3ErrorMsg(pParse, "DISTINCT in aggregate must be followed "
            "by an expression");
@@ -64254,7 +72226,7 @@ static void updateAccumulator(Parse *pParse, AggInfo *pAggInfo){
     if( pList ){
       nArg = pList->nExpr;
       regAgg = sqlite3GetTempRange(pParse, nArg);
-      sqlite3ExprCodeExprList(pParse, pList, regAgg);
+      sqlite3ExprCodeExprList(pParse, pList, regAgg, 0);
     }else{
       nArg = 0;
       regAgg = 0;
@@ -64264,11 +72236,11 @@ static void updateAccumulator(Parse *pParse, AggInfo *pAggInfo){
       assert( nArg==1 );
       codeDistinct(pParse, pF->iDistinct, addrNext, 1, regAgg);
     }
-    if( pF->pFunc->needCollSeq ){
+    if( pF->pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
       CollSeq *pColl = 0;
       struct ExprList_item *pItem;
       int j;
-      assert( pList!=0 );  /* pList!=0 if pF->pFunc->needCollSeq is true */
+      assert( pList!=0 );  /* pList!=0 if pF->pFunc has NEEDCOLL */
       for(j=0, pItem=pList->a; !pColl && jpExpr);
       }
@@ -64281,6 +72253,7 @@ static void updateAccumulator(Parse *pParse, AggInfo *pAggInfo){
                       (void*)pF->pFunc, P4_FUNCDEF);
     sqlite3VdbeChangeP5(v, nArg);
     sqlite3ReleaseTempRange(pParse, regAgg, nArg);
+    sqlite3ExprCacheAffinityChange(pParse, regAgg, nArg);
     if( addrNext ){
       sqlite3VdbeResolveLabel(v, addrNext);
     }
@@ -64291,35 +72264,8 @@ static void updateAccumulator(Parse *pParse, AggInfo *pAggInfo){
   pAggInfo->directMode = 0;
 }
 
-#ifndef SQLITE_OMIT_TRIGGER
-/*
-** This function is used when a SELECT statement is used to create a
-** temporary table for iterating through when running an INSTEAD OF
-** UPDATE or INSTEAD OF DELETE trigger. 
-**
-** If possible, the SELECT statement is modified so that NULL values
-** are stored in the temporary table for all columns for which the 
-** corresponding bit in argument mask is not set. If mask takes the
-** special value 0xffffffff, then all columns are populated.
-*/
-SQLITE_PRIVATE void sqlite3SelectMask(Parse *pParse, Select *p, u32 mask){
-  if( p && !p->pPrior && !p->isDistinct && mask!=0xffffffff ){
-    ExprList *pEList;
-    int i;
-    sqlite3SelectResolve(pParse, p, 0);
-    pEList = p->pEList;
-    for(i=0; pEList && inExpr && i<32; i++){
-      if( !(mask&((u32)1<a[i].pExpr);
-        pEList->a[i].pExpr = sqlite3Expr(pParse->db, TK_NULL, 0, 0, 0);
-      }
-    }
-  }
-}
-#endif
-
 /*
-** Generate code for the given SELECT statement.
+** Generate code for the SELECT statement given in the p argument.  
 **
 ** The results are distributed in various ways depending on the
 ** contents of the SelectDest structure pointed to by argument pDest
@@ -64327,34 +72273,43 @@ SQLITE_PRIVATE void sqlite3SelectMask(Parse *pParse, Select *p, u32 mask){
 **
 **     pDest->eDest    Result
 **     ------------    -------------------------------------------
-**     SRT_Callback    Invoke the callback for each row of the result.
+**     SRT_Output      Generate a row of output (using the OP_ResultRow
+**                     opcode) for each row in the result set.
 **
-**     SRT_Mem         Store first result in memory cell pDest->iParm
+**     SRT_Mem         Only valid if the result is a single column.
+**                     Store the first column of the first result row
+**                     in register pDest->iParm then abandon the rest
+**                     of the query.  This destination implies "LIMIT 1".
 **
-**     SRT_Set         Store non-null results as keys of table pDest->iParm. 
-**                     Apply the affinity pDest->affinity before storing them.
+**     SRT_Set         The result must be a single column.  Store each
+**                     row of result as the key in table pDest->iParm. 
+**                     Apply the affinity pDest->affinity before storing
+**                     results.  Used to implement "IN (SELECT ...)".
 **
 **     SRT_Union       Store results as a key in a temporary table pDest->iParm.
 **
 **     SRT_Except      Remove results from the temporary table pDest->iParm.
 **
-**     SRT_Table       Store results in temporary table pDest->iParm
+**     SRT_Table       Store results in temporary table pDest->iParm.
+**                     This is like SRT_EphemTab except that the table
+**                     is assumed to already be open.
 **
 **     SRT_EphemTab    Create an temporary table pDest->iParm and store
 **                     the result there. The cursor is left open after
-**                     returning.
+**                     returning.  This is like SRT_Table except that
+**                     this destination uses OP_OpenEphemeral to create
+**                     the table first.
 **
-**     SRT_Subroutine  For each row returned, push the results onto the
-**                     vdbe stack and call the subroutine (via OP_Gosub)
-**                     at address pDest->iParm.
+**     SRT_Coroutine   Generate a co-routine that returns a new row of
+**                     results each time it is invoked.  The entry point
+**                     of the co-routine is stored in register pDest->iParm.
 **
 **     SRT_Exists      Store a 1 in memory cell pDest->iParm if the result
 **                     set is not empty.
 **
-**     SRT_Discard     Throw the results away.
-**
-** See the selectInnerLoop() function for a canonical listing of the 
-** allowed values of eDest and their meanings.
+**     SRT_Discard     Throw the results away.  This is used by SELECT
+**                     statements within triggers whose only purpose is
+**                     the side-effects of functions.
 **
 ** This routine returns the number of errors.  If any errors are
 ** encountered, then an appropriate error message is left in
@@ -64362,36 +72317,11 @@ SQLITE_PRIVATE void sqlite3SelectMask(Parse *pParse, Select *p, u32 mask){
 **
 ** This routine does NOT free the Select structure passed in.  The
 ** calling function needs to do that.
-**
-** The pParent, parentTab, and *pParentAgg fields are filled in if this
-** SELECT is a subquery.  This routine may try to combine this SELECT
-** with its parent to form a single flat query.  In so doing, it might
-** change the parent query from a non-aggregate to an aggregate query.
-** For that reason, the pParentAgg flag is passed as a pointer, so it
-** can be changed.
-**
-** Example 1:   The meaning of the pParent parameter.
-**
-**    SELECT * FROM t1 JOIN (SELECT x, count(*) FROM t2) JOIN t3;
-**    \                      \_______ subquery _______/        /
-**     \                                                      /
-**      \____________________ outer query ___________________/
-**
-** This routine is called for the outer query first.   For that call,
-** pParent will be NULL.  During the processing of the outer query, this 
-** routine is called recursively to handle the subquery.  For the recursive
-** call, pParent will point to the outer query.  Because the subquery is
-** the second element in a three-way join, the parentTab parameter will
-** be 1 (the 2nd value of a 0-indexed array.)
 */
 SQLITE_PRIVATE int sqlite3Select(
   Parse *pParse,         /* The parser context */
   Select *p,             /* The SELECT statement being coded. */
-  SelectDest *pDest,     /* What to do with the query results */
-  Select *pParent,       /* Another SELECT for which this is a sub-query */
-  int parentTab,         /* Index in pParent->pSrc of this query */
-  int *pParentAgg,       /* True if pParent uses aggregate functions */
-  char *aff              /* If eDest is SRT_Union, the affinity string */
+  SelectDest *pDest      /* What to do with the query results */
 ){
   int i, j;              /* Loop counters */
   WhereInfo *pWInfo;     /* Return from sqlite3WhereBegin() */
@@ -64427,42 +72357,19 @@ SQLITE_PRIVATE int sqlite3Select(
     */
     assert(pDest->eDest==SRT_Exists || pDest->eDest==SRT_Union || 
            pDest->eDest==SRT_Except || pDest->eDest==SRT_Discard);
-    p->isDistinct = 0;
+    p->selFlags &= ~SF_Distinct;
   }
-  if( sqlite3SelectResolve(pParse, p, 0) ){
+  sqlite3SelectPrep(pParse, p, 0);
+  if( pParse->nErr ){
     goto select_end;
   }
   p->pOrderBy = pOrderBy;
 
-#ifndef SQLITE_OMIT_COMPOUND_SELECT
-  /* If there is are a sequence of queries, do the earlier ones first.
-  */
-  if( p->pPrior ){
-    if( p->pRightmost==0 ){
-      Select *pLoop, *pRight = 0;
-      int cnt = 0;
-      for(pLoop=p; pLoop; pLoop=pLoop->pPrior, cnt++){
-        pLoop->pRightmost = p;
-        pLoop->pNext = pRight;
-        pRight = pLoop;
-      }
-      if( SQLITE_MAX_COMPOUND_SELECT>0 && cnt>SQLITE_MAX_COMPOUND_SELECT ){
-        sqlite3ErrorMsg(pParse, "too many terms in compound SELECT");
-        return 1;
-      }
-    }
-    return multiSelect(pParse, p, pDest, aff);
-  }
-#endif
 
   /* Make local copies of the parameters for this query.
   */
   pTabList = p->pSrc;
-  pWhere = p->pWhere;
-  pGroupBy = p->pGroupBy;
-  pHaving = p->pHaving;
-  isAgg = p->isAgg;
-  isDistinct = p->isDistinct;
+  isAgg = (p->selFlags & SF_Aggregate)!=0;
   pEList = p->pEList;
   if( pEList==0 ) goto select_end;
 
@@ -64472,15 +72379,6 @@ SQLITE_PRIVATE int sqlite3Select(
   */
   if( pParse->nErr>0 ) goto select_end;
 
-  /* If writing to memory or generating a set
-  ** only a single column may be output.
-  */
-#ifndef SQLITE_OMIT_SUBQUERY
-  if( checkForMultiColumnSelectError(pParse, pDest, pEList->nExpr) ){
-    goto select_end;
-  }
-#endif
-
   /* ORDER BY is ignored for some destinations.
   */
   if( IgnorableOrderby(pDest) ){
@@ -64495,21 +72393,14 @@ SQLITE_PRIVATE int sqlite3Select(
   /* Generate code for all sub-queries in the FROM clause
   */
 #if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW)
-  for(i=0; inSrc; i++){
-    const char *zSavedAuthContext = 0;
-    int needRestoreContext;
+  for(i=0; !p->pPrior && inSrc; i++){
     struct SrcList_item *pItem = &pTabList->a[i];
     SelectDest dest;
+    Select *pSub = pItem->pSelect;
+    int isAggSub;
+
+    if( pSub==0 || pItem->isPopulated ) continue;
 
-    if( pItem->pSelect==0 || pItem->isPopulated ) continue;
-    if( pItem->zName!=0 ){
-      zSavedAuthContext = pParse->zAuthContext;
-      pParse->zAuthContext = pItem->zName;
-      needRestoreContext = 1;
-    }else{
-      needRestoreContext = 0;
-    }
-#if defined(SQLITE_TEST) || SQLITE_MAX_EXPR_DEPTH>0
     /* Increment Parse.nHeight by the height of the largest expression
     ** tree refered to by this, the parent select. The child select
     ** may contain expression trees of at most
@@ -64518,47 +72409,76 @@ SQLITE_PRIVATE int sqlite3Select(
     ** an exact limit.
     */
     pParse->nHeight += sqlite3SelectExprHeight(p);
-#endif
-    sqlite3SelectDestInit(&dest, SRT_EphemTab, pItem->iCursor);
-    sqlite3Select(pParse, pItem->pSelect, &dest, p, i, &isAgg, 0);
-    if( db->mallocFailed ){
+
+    /* Check to see if the subquery can be absorbed into the parent. */
+    isAggSub = (pSub->selFlags & SF_Aggregate)!=0;
+    if( flattenSubquery(pParse, p, i, isAgg, isAggSub) ){
+      if( isAggSub ){
+        isAgg = 1;
+        p->selFlags |= SF_Aggregate;
+      }
+      i = -1;
+    }else{
+      sqlite3SelectDestInit(&dest, SRT_EphemTab, pItem->iCursor);
+      assert( pItem->isPopulated==0 );
+      sqlite3Select(pParse, pSub, &dest);
+      pItem->isPopulated = 1;
+    }
+    if( pParse->nErr || db->mallocFailed ){
       goto select_end;
     }
-#if defined(SQLITE_TEST) || SQLITE_MAX_EXPR_DEPTH>0
     pParse->nHeight -= sqlite3SelectExprHeight(p);
-#endif
-    if( needRestoreContext ){
-      pParse->zAuthContext = zSavedAuthContext;
-    }
     pTabList = p->pSrc;
-    pWhere = p->pWhere;
     if( !IgnorableOrderby(pDest) ){
       pOrderBy = p->pOrderBy;
     }
-    pGroupBy = p->pGroupBy;
-    pHaving = p->pHaving;
-    isDistinct = p->isDistinct;
   }
+  pEList = p->pEList;
 #endif
+  pWhere = p->pWhere;
+  pGroupBy = p->pGroupBy;
+  pHaving = p->pHaving;
+  isDistinct = (p->selFlags & SF_Distinct)!=0;
 
-  /* Check to see if this is a subquery that can be "flattened" into its parent.
-  ** If flattening is a possiblity, do so and return immediately.  
+#ifndef SQLITE_OMIT_COMPOUND_SELECT
+  /* If there is are a sequence of queries, do the earlier ones first.
   */
-#ifndef SQLITE_OMIT_VIEW
-  if( pParent && pParentAgg &&
-      flattenSubquery(db, pParent, parentTab, *pParentAgg, isAgg) ){
-    if( isAgg ) *pParentAgg = 1;
+  if( p->pPrior ){
+    if( p->pRightmost==0 ){
+      Select *pLoop, *pRight = 0;
+      int cnt = 0;
+      int mxSelect;
+      for(pLoop=p; pLoop; pLoop=pLoop->pPrior, cnt++){
+        pLoop->pRightmost = p;
+        pLoop->pNext = pRight;
+        pRight = pLoop;
+      }
+      mxSelect = db->aLimit[SQLITE_LIMIT_COMPOUND_SELECT];
+      if( mxSelect && cnt>mxSelect ){
+        sqlite3ErrorMsg(pParse, "too many terms in compound SELECT");
+        return 1;
+      }
+    }
+    return multiSelect(pParse, p, pDest);
+  }
+#endif
+
+  /* If writing to memory or generating a set
+  ** only a single column may be output.
+  */
+#ifndef SQLITE_OMIT_SUBQUERY
+  if( checkForMultiColumnSelectError(pParse, pDest, pEList->nExpr) ){
     goto select_end;
   }
 #endif
 
   /* If possible, rewrite the query to use GROUP BY instead of DISTINCT.
-  ** GROUP BY may use an index, DISTINCT never does.
+  ** GROUP BY might use an index, DISTINCT never does.
   */
-  if( p->isDistinct && !p->isAgg && !p->pGroupBy ){
+  if( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct && !p->pGroupBy ){
     p->pGroupBy = sqlite3ExprListDup(db, p->pEList);
     pGroupBy = p->pGroupBy;
-    p->isDistinct = 0;
+    p->selFlags &= ~SF_Distinct;
     isDistinct = 0;
   }
 
@@ -64626,7 +72546,7 @@ SQLITE_PRIVATE int sqlite3Select(
     */
     assert(!isDistinct);
     selectInnerLoop(pParse, p, pEList, 0, 0, pOrderBy, -1, pDest,
-                    pWInfo->iContinue, pWInfo->iBreak, aff);
+                    pWInfo->iContinue, pWInfo->iBreak);
 
     /* End the database scan loop.
     */
@@ -64641,20 +72561,25 @@ SQLITE_PRIVATE int sqlite3Select(
                         ** processed */
     int iAbortFlag;     /* Mem address which causes query abort if positive */
     int groupBySort;    /* Rows come from source in GROUP BY order */
+    int addrEnd;        /* End of processing for this SELECT */
 
+    /* Remove any and all aliases between the result set and the
+    ** GROUP BY clause.
+    */
+    if( pGroupBy ){
+      int i;                        /* Loop counter */
+      struct ExprList_item *pItem;  /* For looping over expression in a list */
 
-    /* The following variables hold addresses or labels for parts of the
-    ** virtual machine program we are putting together */
-    int addrOutputRow;      /* Start of subroutine that outputs a result row */
-    int addrSetAbort;       /* Set the abort flag and return */
-    int addrInitializeLoop; /* Start of code that initializes the input loop */
-    int addrTopOfLoop;      /* Top of the input loop */
-    int addrGroupByChange;  /* Code that runs when any GROUP BY term changes */
-    int addrProcessRow;     /* Code to process a single input row */
-    int addrEnd;            /* End of all processing */
-    int addrSortingIdx;     /* The OP_OpenEphemeral for the sorting index */
-    int addrReset;          /* Subroutine for resetting the accumulator */
+      for(i=p->pEList->nExpr, pItem=p->pEList->a; i>0; i--, pItem++){
+        pItem->iAlias = 0;
+      }
+      for(i=pGroupBy->nExpr, pItem=pGroupBy->a; i>0; i--, pItem++){
+        pItem->iAlias = 0;
+      }
+    }
 
+ 
+    /* Create a label to jump to when we want to abort the query */
     addrEnd = sqlite3VdbeMakeLabel(v);
 
     /* Convert TK_COLUMN nodes into TK_AGG_COLUMN and make entries in
@@ -64683,13 +72608,14 @@ SQLITE_PRIVATE int sqlite3Select(
     */
     if( pGroupBy ){
       KeyInfo *pKeyInfo;  /* Keying information for the group by clause */
-
-      /* Create labels that we will be needing
-      */
-     
-      addrInitializeLoop = sqlite3VdbeMakeLabel(v);
-      addrGroupByChange = sqlite3VdbeMakeLabel(v);
-      addrProcessRow = sqlite3VdbeMakeLabel(v);
+      int j1;             /* A-vs-B comparision jump */
+      int addrOutputRow;  /* Start of subroutine that outputs a result row */
+      int regOutputRow;   /* Return address register for output subroutine */
+      int addrSetAbort;   /* Set the abort flag and return */
+      int addrTopOfLoop;  /* Top of the input loop */
+      int addrSortingIdx; /* The OP_OpenEphemeral for the sorting index */
+      int addrReset;      /* Subroutine for resetting the accumulator */
+      int regReset;       /* Return address register for reset subroutine */
 
       /* If there is a GROUP BY clause we might need a sorting index to
       ** implement it.  Allocate that sorting index now.  If it turns out
@@ -64698,15 +72624,18 @@ SQLITE_PRIVATE int sqlite3Select(
       */
       sAggInfo.sortingIdx = pParse->nTab++;
       pKeyInfo = keyInfoFromExprList(pParse, pGroupBy);
-      addrSortingIdx =
-          sqlite3VdbeAddOp4(v, OP_OpenEphemeral, sAggInfo.sortingIdx,
-                         sAggInfo.nSortingColumn, 0,
-                         (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
+      addrSortingIdx = sqlite3VdbeAddOp4(v, OP_OpenEphemeral, 
+          sAggInfo.sortingIdx, sAggInfo.nSortingColumn, 
+          0, (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
 
       /* Initialize memory locations used by GROUP BY aggregate processing
       */
       iUseFlag = ++pParse->nMem;
       iAbortFlag = ++pParse->nMem;
+      regOutputRow = ++pParse->nMem;
+      addrOutputRow = sqlite3VdbeMakeLabel(v);
+      regReset = ++pParse->nMem;
+      addrReset = sqlite3VdbeMakeLabel(v);
       iAMem = pParse->nMem + 1;
       pParse->nMem += pGroupBy->nExpr;
       iBMem = pParse->nMem + 1;
@@ -64715,46 +72644,13 @@ SQLITE_PRIVATE int sqlite3Select(
       VdbeComment((v, "clear abort flag"));
       sqlite3VdbeAddOp2(v, OP_Integer, 0, iUseFlag);
       VdbeComment((v, "indicate accumulator empty"));
-      sqlite3VdbeAddOp2(v, OP_Goto, 0, addrInitializeLoop);
-
-      /* Generate a subroutine that outputs a single row of the result
-      ** set.  This subroutine first looks at the iUseFlag.  If iUseFlag
-      ** is less than or equal to zero, the subroutine is a no-op.  If
-      ** the processing calls for the query to abort, this subroutine
-      ** increments the iAbortFlag memory location before returning in
-      ** order to signal the caller to abort.
-      */
-      addrSetAbort = sqlite3VdbeCurrentAddr(v);
-      sqlite3VdbeAddOp2(v, OP_Integer, 1, iAbortFlag);
-      VdbeComment((v, "set abort flag"));
-      sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
-      addrOutputRow = sqlite3VdbeCurrentAddr(v);
-      sqlite3VdbeAddOp2(v, OP_IfPos, iUseFlag, addrOutputRow+2);
-      VdbeComment((v, "Groupby result generator entry point"));
-      sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
-      finalizeAggFunctions(pParse, &sAggInfo);
-      if( pHaving ){
-        sqlite3ExprIfFalse(pParse, pHaving, addrOutputRow+1, SQLITE_JUMPIFNULL);
-      }
-      selectInnerLoop(pParse, p, p->pEList, 0, 0, pOrderBy,
-                      distinct, pDest,
-                      addrOutputRow+1, addrSetAbort, aff);
-      sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
-      VdbeComment((v, "end groupby result generator"));
-
-      /* Generate a subroutine that will reset the group-by accumulator
-      */
-      addrReset = sqlite3VdbeCurrentAddr(v);
-      resetAccumulator(pParse, &sAggInfo);
-      sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
 
       /* Begin a loop that will extract all source rows in GROUP BY order.
       ** This might involve two separate loops with an OP_Sort in between, or
       ** it might be a single loop that uses an index to extract information
       ** in the right order to begin with.
       */
-      sqlite3VdbeResolveLabel(v, addrInitializeLoop);
-      sqlite3VdbeAddOp2(v, OP_Gosub, 0, addrReset);
+      sqlite3VdbeAddOp2(v, OP_Gosub, regReset, addrReset);
       pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pGroupBy, 0);
       if( pWInfo==0 ) goto select_end;
       if( pGroupBy==0 ){
@@ -64786,14 +72682,20 @@ SQLITE_PRIVATE int sqlite3Select(
           }
         }
         regBase = sqlite3GetTempRange(pParse, nCol);
-        sqlite3ExprCodeExprList(pParse, pGroupBy, regBase);
+        sqlite3ExprCodeExprList(pParse, pGroupBy, regBase, 0);
         sqlite3VdbeAddOp2(v, OP_Sequence, sAggInfo.sortingIdx,regBase+nGroupBy);
         j = nGroupBy+1;
         for(i=0; iiSorterColumn>=j ){
-            sqlite3ExprCodeGetColumn(v, pCol->pTab, pCol->iColumn, pCol->iTable,
-                                     j + regBase);
+            int r1 = j + regBase;
+            int r2;
+
+            r2 = sqlite3ExprCodeGetColumn(pParse, 
+                               pCol->pTab, pCol->iColumn, pCol->iTable, r1, 0);
+            if( r1!=r2 ){
+              sqlite3VdbeAddOp2(v, OP_SCopy, r2, r1);
+            }
             j++;
           }
         }
@@ -64822,18 +72724,13 @@ SQLITE_PRIVATE int sqlite3Select(
           sqlite3ExprCode(pParse, pGroupBy->a[j].pExpr, iBMem+j);
         }
       }
-      for(j=pGroupBy->nExpr-1; j>=0; j--){
-        if( j==0 ){
-          sqlite3VdbeAddOp3(v, OP_Eq, iAMem+j, addrProcessRow, iBMem+j);
-        }else{
-          sqlite3VdbeAddOp3(v, OP_Ne, iAMem+j, addrGroupByChange, iBMem+j);
-        }
-        sqlite3VdbeChangeP4(v, -1, (void*)pKeyInfo->aColl[j], P4_COLLSEQ);
-        sqlite3VdbeChangeP5(v, SQLITE_NULLEQUAL);
-      }
+      sqlite3VdbeAddOp4(v, OP_Compare, iAMem, iBMem, pGroupBy->nExpr,
+                          (char*)pKeyInfo, P4_KEYINFO);
+      j1 = sqlite3VdbeCurrentAddr(v);
+      sqlite3VdbeAddOp3(v, OP_Jump, j1+1, 0, j1+1);
 
       /* Generate code that runs whenever the GROUP BY changes.
-      ** Change in the GROUP BY are detected by the previous code
+      ** Changes in the GROUP BY are detected by the previous code
       ** block.  If there were no changes, this block is skipped.
       **
       ** This code copies current group by terms in b0,b1,b2,...
@@ -64841,21 +72738,18 @@ SQLITE_PRIVATE int sqlite3Select(
       ** and resets the aggregate accumulator registers in preparation
       ** for the next GROUP BY batch.
       */
-      sqlite3VdbeResolveLabel(v, addrGroupByChange);
-      for(j=0; jnExpr; j++){
-        sqlite3VdbeAddOp2(v, OP_Move, iBMem+j, iAMem+j);
-      }
-      sqlite3VdbeAddOp2(v, OP_Gosub, 0, addrOutputRow);
+      sqlite3ExprCodeMove(pParse, iBMem, iAMem, pGroupBy->nExpr);
+      sqlite3VdbeAddOp2(v, OP_Gosub, regOutputRow, addrOutputRow);
       VdbeComment((v, "output one row"));
       sqlite3VdbeAddOp2(v, OP_IfPos, iAbortFlag, addrEnd);
       VdbeComment((v, "check abort flag"));
-      sqlite3VdbeAddOp2(v, OP_Gosub, 0, addrReset);
+      sqlite3VdbeAddOp2(v, OP_Gosub, regReset, addrReset);
       VdbeComment((v, "reset accumulator"));
 
       /* Update the aggregate accumulators based on the content of
       ** the current row
       */
-      sqlite3VdbeResolveLabel(v, addrProcessRow);
+      sqlite3VdbeJumpHere(v, j1);
       updateAccumulator(pParse, &sAggInfo);
       sqlite3VdbeAddOp2(v, OP_Integer, 1, iUseFlag);
       VdbeComment((v, "indicate data in accumulator"));
@@ -64871,9 +72765,45 @@ SQLITE_PRIVATE int sqlite3Select(
 
       /* Output the final row of result
       */
-      sqlite3VdbeAddOp2(v, OP_Gosub, 0, addrOutputRow);
+      sqlite3VdbeAddOp2(v, OP_Gosub, regOutputRow, addrOutputRow);
       VdbeComment((v, "output final row"));
-      
+
+      /* Jump over the subroutines
+      */
+      sqlite3VdbeAddOp2(v, OP_Goto, 0, addrEnd);
+
+      /* Generate a subroutine that outputs a single row of the result
+      ** set.  This subroutine first looks at the iUseFlag.  If iUseFlag
+      ** is less than or equal to zero, the subroutine is a no-op.  If
+      ** the processing calls for the query to abort, this subroutine
+      ** increments the iAbortFlag memory location before returning in
+      ** order to signal the caller to abort.
+      */
+      addrSetAbort = sqlite3VdbeCurrentAddr(v);
+      sqlite3VdbeAddOp2(v, OP_Integer, 1, iAbortFlag);
+      VdbeComment((v, "set abort flag"));
+      sqlite3VdbeAddOp1(v, OP_Return, regOutputRow);
+      sqlite3VdbeResolveLabel(v, addrOutputRow);
+      addrOutputRow = sqlite3VdbeCurrentAddr(v);
+      sqlite3VdbeAddOp2(v, OP_IfPos, iUseFlag, addrOutputRow+2);
+      VdbeComment((v, "Groupby result generator entry point"));
+      sqlite3VdbeAddOp1(v, OP_Return, regOutputRow);
+      finalizeAggFunctions(pParse, &sAggInfo);
+      if( pHaving ){
+        sqlite3ExprIfFalse(pParse, pHaving, addrOutputRow+1, SQLITE_JUMPIFNULL);
+      }
+      selectInnerLoop(pParse, p, p->pEList, 0, 0, pOrderBy,
+                      distinct, pDest,
+                      addrOutputRow+1, addrSetAbort);
+      sqlite3VdbeAddOp1(v, OP_Return, regOutputRow);
+      VdbeComment((v, "end groupby result generator"));
+
+      /* Generate a subroutine that will reset the group-by accumulator
+      */
+      sqlite3VdbeResolveLabel(v, addrReset);
+      resetAccumulator(pParse, &sAggInfo);
+      sqlite3VdbeAddOp1(v, OP_Return, regReset);
+     
     } /* endif pGroupBy */
     else {
       ExprList *pMinMax = 0;
@@ -64909,7 +72839,7 @@ SQLITE_PRIVATE int sqlite3Select(
       if( flag ){
         pDel = pMinMax = sqlite3ExprListDup(db, p->pEList->a[0].pExpr->pList);
         if( pMinMax && !db->mallocFailed ){
-          pMinMax->a[0].sortOrder = ((flag==ORDERBY_MIN)?0:1);
+          pMinMax->a[0].sortOrder = flag!=WHERE_ORDERBY_MIN;
           pMinMax->a[0].pExpr->op = TK_COLUMN;
         }
       }
@@ -64921,13 +72851,13 @@ SQLITE_PRIVATE int sqlite3Select(
       resetAccumulator(pParse, &sAggInfo);
       pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pMinMax, flag);
       if( pWInfo==0 ){
-        sqlite3ExprListDelete(pDel);
+        sqlite3ExprListDelete(db, pDel);
         goto select_end;
       }
       updateAccumulator(pParse, &sAggInfo);
       if( !pMinMax && flag ){
         sqlite3VdbeAddOp2(v, OP_Goto, 0, pWInfo->iBreak);
-        VdbeComment((v, "%s() by index", (flag==ORDERBY_MIN?"min":"max")));
+        VdbeComment((v, "%s() by index",(flag==WHERE_ORDERBY_MIN?"min":"max")));
       }
       sqlite3WhereEnd(pWInfo);
       finalizeAggFunctions(pParse, &sAggInfo);
@@ -64936,9 +72866,9 @@ SQLITE_PRIVATE int sqlite3Select(
         sqlite3ExprIfFalse(pParse, pHaving, addrEnd, SQLITE_JUMPIFNULL);
       }
       selectInnerLoop(pParse, p, p->pEList, 0, 0, 0, -1, 
-                      pDest, addrEnd, addrEnd, aff);
+                      pDest, addrEnd, addrEnd);
 
-      sqlite3ExprListDelete(pDel);
+      sqlite3ExprListDelete(db, pDel);
     }
     sqlite3VdbeResolveLabel(v, addrEnd);
     
@@ -64951,19 +72881,6 @@ SQLITE_PRIVATE int sqlite3Select(
     generateSortTail(pParse, p, v, pEList->nExpr, pDest);
   }
 
-#ifndef SQLITE_OMIT_SUBQUERY
-  /* If this was a subquery, we have now converted the subquery into a
-  ** temporary table.  So set the SrcList_item.isPopulated flag to prevent
-  ** this subquery from being evaluated again and to force the use of
-  ** the temporary table.
-  */
-  if( pParent ){
-    assert( pParent->pSrc->nSrc>parentTab );
-    assert( pParent->pSrc->a[parentTab].pSelect==p );
-    pParent->pSrc->a[parentTab].isPopulated = 1;
-  }
-#endif
-
   /* Jump here to skip this query
   */
   sqlite3VdbeResolveLabel(v, iEnd);
@@ -64978,15 +72895,14 @@ SQLITE_PRIVATE int sqlite3Select(
   */
 select_end:
 
-  /* Identify column names if we will be using them in a callback.  This
-  ** step is skipped if the output is going to some other destination.
+  /* Identify column names if results of the SELECT are to be output.
   */
-  if( rc==SQLITE_OK && pDest->eDest==SRT_Callback ){
+  if( rc==SQLITE_OK && pDest->eDest==SRT_Output ){
     generateColumnNames(pParse, pTabList, pEList);
   }
 
-  sqlite3_free(sAggInfo.aCol);
-  sqlite3_free(sAggInfo.aFunc);
+  sqlite3DbFree(db, sAggInfo.aCol);
+  sqlite3DbFree(db, sAggInfo.aFunc);
   return rc;
 }
 
@@ -65005,7 +72921,7 @@ select_end:
 ** code base.  Then are intended to be called from within the debugger
 ** or from temporary "printf" statements inserted for debugging.
 */
-static void sqlite3PrintExpr(Expr *p){
+SQLITE_PRIVATE void sqlite3PrintExpr(Expr *p){
   if( p->token.z && p->token.n>0 ){
     sqlite3DebugPrintf("(%.*s", p->token.n, p->token.z);
   }else{
@@ -65021,7 +72937,7 @@ static void sqlite3PrintExpr(Expr *p){
   }
   sqlite3DebugPrintf(")");
 }
-static void sqlite3PrintExprList(ExprList *pList){
+SQLITE_PRIVATE void sqlite3PrintExprList(ExprList *pList){
   int i;
   for(i=0; inExpr; i++){
     sqlite3PrintExpr(pList->a[i].pExpr);
@@ -65030,7 +72946,7 @@ static void sqlite3PrintExprList(ExprList *pList){
     }
   }
 }
-static void sqlite3PrintSelect(Select *p, int indent){
+SQLITE_PRIVATE void sqlite3PrintSelect(Select *p, int indent){
   sqlite3DebugPrintf("%*sSELECT(%p) ", indent, "", p);
   sqlite3PrintExprList(p->pEList);
   sqlite3DebugPrintf("\n");
@@ -65105,6 +73021,8 @@ static void sqlite3PrintSelect(Select *p, int indent){
 **
 ** These routines are in a separate files so that they will not be linked
 ** if they are not used.
+**
+** $Id: table.c,v 1.36 2008/07/08 22:28:49 shane Exp $
 */
 
 #ifndef SQLITE_OMIT_GET_TABLE
@@ -65232,7 +73150,7 @@ SQLITE_API int sqlite3_get_table(
   res.azResult[0] = 0;
   rc = sqlite3_exec(db, zSql, sqlite3_get_table_cb, &res, pzErrMsg);
   assert( sizeof(res.azResult[0])>= sizeof(res.nData) );
-  res.azResult[0] = (char*)(sqlite3_intptr_t)res.nData;
+  res.azResult[0] = SQLITE_INT_TO_PTR(res.nData);
   if( (rc&0xff)==SQLITE_ABORT ){
     sqlite3_free_table(&res.azResult[1]);
     if( res.zErrMsg ){
@@ -65274,10 +73192,10 @@ SQLITE_API void sqlite3_free_table(
   char **azResult            /* Result returned from from sqlite3_get_table() */
 ){
   if( azResult ){
-    sqlite3_intptr_t i, n;
+    int i, n;
     azResult--;
     assert( azResult!=0 );
-    n = (sqlite3_intptr_t)azResult[0];
+    n = SQLITE_PTR_TO_INT(azResult[0]);
     for(i=1; ipNext;
 
-    if( pTmp->target.dyn ) sqlite3_free((char*)pTmp->target.z);
-    sqlite3ExprDelete(pTmp->pWhere);
-    sqlite3ExprListDelete(pTmp->pExprList);
-    sqlite3SelectDelete(pTmp->pSelect);
-    sqlite3IdListDelete(pTmp->pIdList);
+    if( pTmp->target.dyn ) sqlite3DbFree(db, (char*)pTmp->target.z);
+    sqlite3ExprDelete(db, pTmp->pWhere);
+    sqlite3ExprListDelete(db, pTmp->pExprList);
+    sqlite3SelectDelete(db, pTmp->pSelect);
+    sqlite3IdListDelete(db, pTmp->pIdList);
 
-    sqlite3_free(pTmp);
+    sqlite3DbFree(db, pTmp);
   }
 }
 
@@ -65472,12 +73392,12 @@ SQLITE_PRIVATE void sqlite3BeginTrigger(
   pParse->pNewTrigger = pTrigger;
 
 trigger_cleanup:
-  sqlite3_free(zName);
-  sqlite3SrcListDelete(pTableName);
-  sqlite3IdListDelete(pColumns);
-  sqlite3ExprDelete(pWhen);
+  sqlite3DbFree(db, zName);
+  sqlite3SrcListDelete(db, pTableName);
+  sqlite3IdListDelete(db, pColumns);
+  sqlite3ExprDelete(db, pWhen);
   if( !pParse->pNewTrigger ){
-    sqlite3DeleteTrigger(pTrigger);
+    sqlite3DeleteTrigger(db, pTrigger);
   }else{
     assert( pParse->pNewTrigger==pTrigger );
   }
@@ -65527,7 +73447,7 @@ SQLITE_PRIVATE void sqlite3FinishTrigger(
        "INSERT INTO %Q.%s VALUES('trigger',%Q,%Q,0,'CREATE TRIGGER %q')",
        db->aDb[iDb].zName, SCHEMA_TABLE(iDb), pTrig->name,
        pTrig->table, z);
-    sqlite3_free(z);
+    sqlite3DbFree(db, z);
     sqlite3ChangeCookie(pParse, iDb);
     sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 0, 0, sqlite3MPrintf(
         db, "type='trigger' AND name='%q'", pTrig->name), P4_DYNAMIC
@@ -65554,9 +73474,9 @@ SQLITE_PRIVATE void sqlite3FinishTrigger(
   }
 
 triggerfinish_cleanup:
-  sqlite3DeleteTrigger(pTrig);
+  sqlite3DeleteTrigger(db, pTrig);
   assert( !pParse->pNewTrigger );
-  sqlite3DeleteTriggerStep(pStepList);
+  sqlite3DeleteTriggerStep(db, pStepList);
 }
 
 /*
@@ -65576,22 +73496,22 @@ static void sqlitePersistTriggerStep(sqlite3 *db, TriggerStep *p){
   }
   if( p->pSelect ){
     Select *pNew = sqlite3SelectDup(db, p->pSelect);
-    sqlite3SelectDelete(p->pSelect);
+    sqlite3SelectDelete(db, p->pSelect);
     p->pSelect = pNew;
   }
   if( p->pWhere ){
     Expr *pNew = sqlite3ExprDup(db, p->pWhere);
-    sqlite3ExprDelete(p->pWhere);
+    sqlite3ExprDelete(db, p->pWhere);
     p->pWhere = pNew;
   }
   if( p->pExprList ){
     ExprList *pNew = sqlite3ExprListDup(db, p->pExprList);
-    sqlite3ExprListDelete(p->pExprList);
+    sqlite3ExprListDelete(db, p->pExprList);
     p->pExprList = pNew;
   }
   if( p->pIdList ){
     IdList *pNew = sqlite3IdListDup(db, p->pIdList);
-    sqlite3IdListDelete(p->pIdList);
+    sqlite3IdListDelete(db, p->pIdList);
     p->pIdList = pNew;
   }
 }
@@ -65606,7 +73526,7 @@ static void sqlitePersistTriggerStep(sqlite3 *db, TriggerStep *p){
 SQLITE_PRIVATE TriggerStep *sqlite3TriggerSelectStep(sqlite3 *db, Select *pSelect){
   TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
   if( pTriggerStep==0 ) {
-    sqlite3SelectDelete(pSelect);
+    sqlite3SelectDelete(db, pSelect);
     return 0;
   }
 
@@ -65648,9 +73568,9 @@ SQLITE_PRIVATE TriggerStep *sqlite3TriggerInsertStep(
     pTriggerStep->orconf = orconf;
     sqlitePersistTriggerStep(db, pTriggerStep);
   }else{
-    sqlite3IdListDelete(pColumn);
-    sqlite3ExprListDelete(pEList);
-    sqlite3SelectDelete(pSelect);
+    sqlite3IdListDelete(db, pColumn);
+    sqlite3ExprListDelete(db, pEList);
+    sqlite3SelectDelete(db, pSelect);
   }
 
   return pTriggerStep;
@@ -65670,8 +73590,8 @@ SQLITE_PRIVATE TriggerStep *sqlite3TriggerUpdateStep(
 ){
   TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
   if( pTriggerStep==0 ){
-     sqlite3ExprListDelete(pEList);
-     sqlite3ExprDelete(pWhere);
+     sqlite3ExprListDelete(db, pEList);
+     sqlite3ExprDelete(db, pWhere);
      return 0;
   }
 
@@ -65697,7 +73617,7 @@ SQLITE_PRIVATE TriggerStep *sqlite3TriggerDeleteStep(
 ){
   TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
   if( pTriggerStep==0 ){
-    sqlite3ExprDelete(pWhere);
+    sqlite3ExprDelete(db, pWhere);
     return 0;
   }
 
@@ -65713,15 +73633,15 @@ SQLITE_PRIVATE TriggerStep *sqlite3TriggerDeleteStep(
 /* 
 ** Recursively delete a Trigger structure
 */
-SQLITE_PRIVATE void sqlite3DeleteTrigger(Trigger *pTrigger){
+SQLITE_PRIVATE void sqlite3DeleteTrigger(sqlite3 *db, Trigger *pTrigger){
   if( pTrigger==0 ) return;
-  sqlite3DeleteTriggerStep(pTrigger->step_list);
-  sqlite3_free(pTrigger->name);
-  sqlite3_free(pTrigger->table);
-  sqlite3ExprDelete(pTrigger->pWhen);
-  sqlite3IdListDelete(pTrigger->pColumns);
-  if( pTrigger->nameToken.dyn ) sqlite3_free((char*)pTrigger->nameToken.z);
-  sqlite3_free(pTrigger);
+  sqlite3DeleteTriggerStep(db, pTrigger->step_list);
+  sqlite3DbFree(db, pTrigger->name);
+  sqlite3DbFree(db, pTrigger->table);
+  sqlite3ExprDelete(db, pTrigger->pWhen);
+  sqlite3IdListDelete(db, pTrigger->pColumns);
+  if( pTrigger->nameToken.dyn ) sqlite3DbFree(db, (char*)pTrigger->nameToken.z);
+  sqlite3DbFree(db, pTrigger);
 }
 
 /*
@@ -65764,7 +73684,7 @@ SQLITE_PRIVATE void sqlite3DropTrigger(Parse *pParse, SrcList *pName, int noErr)
   sqlite3DropTriggerPtr(pParse, pTrigger);
 
 drop_trigger_cleanup:
-  sqlite3SrcListDelete(pName);
+  sqlite3SrcListDelete(db, pName);
 }
 
 /*
@@ -65856,7 +73776,7 @@ SQLITE_PRIVATE void sqlite3UnlinkAndDeleteTrigger(sqlite3 *db, int iDb, const ch
       }
       assert(cc);
     }
-    sqlite3DeleteTrigger(pTrigger);
+    sqlite3DeleteTrigger(db, pTrigger);
     db->flags |= SQLITE_InternChanges;
   }
 }
@@ -65965,9 +73885,8 @@ static int codeTriggerProgram(
           SelectDest dest;
 
           sqlite3SelectDestInit(&dest, SRT_Discard, 0);
-          sqlite3SelectResolve(pParse, ss, 0);
-          sqlite3Select(pParse, ss, &dest, 0, 0, 0, 0);
-          sqlite3SelectDelete(ss);
+          sqlite3Select(pParse, ss, &dest);
+          sqlite3SelectDelete(db, ss);
         }
         break;
       }
@@ -66115,13 +74034,13 @@ SQLITE_PRIVATE int sqlite3CodeRowTrigger(
       /* code the WHEN clause */
       endTrigger = sqlite3VdbeMakeLabel(pParse->pVdbe);
       whenExpr = sqlite3ExprDup(db, p->pWhen);
-      if( db->mallocFailed || sqlite3ExprResolveNames(&sNC, whenExpr) ){
+      if( db->mallocFailed || sqlite3ResolveExprNames(&sNC, whenExpr) ){
         pParse->trigStack = trigStackEntry.pNext;
-        sqlite3ExprDelete(whenExpr);
+        sqlite3ExprDelete(db, whenExpr);
         return 1;
       }
       sqlite3ExprIfFalse(pParse, whenExpr, endTrigger, SQLITE_JUMPIFNULL);
-      sqlite3ExprDelete(whenExpr);
+      sqlite3ExprDelete(db, whenExpr);
 
       codeTriggerProgram(pParse, p->step_list, orconf); 
 
@@ -66154,7 +74073,7 @@ SQLITE_PRIVATE int sqlite3CodeRowTrigger(
 ** This file contains C code routines that are called by the parser
 ** to handle UPDATE statements.
 **
-** $Id: update.c,v 1.171 2008/02/12 16:52:14 drh Exp $
+** $Id: update.c,v 1.185 2008/10/09 18:48:31 danielk1977 Exp $
 */
 
 #ifndef SQLITE_OMIT_VIRTUALTABLE
@@ -66244,6 +74163,7 @@ SQLITE_PRIVATE void sqlite3Update(
   NameContext sNC;       /* The name-context to resolve expressions in */
   int iDb;               /* Database containing the table being updated */
   int j1;                /* Addresses of jump instructions */
+  int okOnePass;         /* True for one-pass algorithm without the FIFO */
 
 #ifndef SQLITE_OMIT_TRIGGER
   int isView;                  /* Trying to update a view */
@@ -66334,7 +74254,7 @@ SQLITE_PRIVATE void sqlite3Update(
   */
   chngRowid = 0;
   for(i=0; inExpr; i++){
-    if( sqlite3ExprResolveNames(&sNC, pChanges->a[i].pExpr) ){
+    if( sqlite3ResolveExprNames(&sNC, pChanges->a[i].pExpr) ){
       goto update_cleanup;
     }
     for(j=0; jnCol; j++){
@@ -66443,10 +74363,10 @@ SQLITE_PRIVATE void sqlite3Update(
 
     /* Create pseudo-tables for NEW and OLD
     */
+    sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
     sqlite3VdbeAddOp2(v, OP_OpenPseudo, oldIdx, 0);
-    sqlite3VdbeAddOp2(v, OP_SetNumColumns, oldIdx, pTab->nCol);
+    sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
     sqlite3VdbeAddOp2(v, OP_OpenPseudo, newIdx, 0);
-    sqlite3VdbeAddOp2(v, OP_SetNumColumns, newIdx, pTab->nCol);
 
     iGoto = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
     addr = sqlite3VdbeMakeLabel(v);
@@ -66468,27 +74388,31 @@ SQLITE_PRIVATE void sqlite3Update(
   /* If we are trying to update a view, realize that view into
   ** a ephemeral table.
   */
+#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
   if( isView ){
-    sqlite3MaterializeView(pParse, pTab->pSelect, pWhere,
-                           old_col_mask|new_col_mask, iCur);
+    sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
   }
+#endif
 
   /* Resolve the column names in all the expressions in the
   ** WHERE clause.
   */
-  if( sqlite3ExprResolveNames(&sNC, pWhere) ){
+  if( sqlite3ResolveExprNames(&sNC, pWhere) ){
     goto update_cleanup;
   }
 
   /* Begin the database scan
   */
-  pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0);
+  sqlite3VdbeAddOp2(v, OP_Null, 0, regOldRowid);
+  pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0,
+                             WHERE_ONEPASS_DESIRED);
   if( pWInfo==0 ) goto update_cleanup;
+  okOnePass = pWInfo->okOnePass;
 
   /* Remember the rowid of every item to be updated.
   */
-  sqlite3VdbeAddOp2(v, IsVirtual(pTab) ? OP_VRowid : OP_Rowid,iCur,regOldRowid);
-  sqlite3VdbeAddOp2(v, OP_FifoWrite, regOldRowid, 0);
+  sqlite3VdbeAddOp2(v, IsVirtual(pTab)?OP_VRowid:OP_Rowid, iCur, regOldRowid);
+  if( !okOnePass ) sqlite3VdbeAddOp2(v, OP_FifoWrite, regOldRowid, 0);
 
   /* End the database scan loop.
   */
@@ -66508,7 +74432,7 @@ SQLITE_PRIVATE void sqlite3Update(
     ** action, then we need to open all indices because we might need
     ** to be deleting some records.
     */
-    sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite); 
+    if( !okOnePass ) sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite); 
     if( onError==OE_Replace ){
       openAll = 1;
     }else{
@@ -66536,7 +74460,13 @@ SQLITE_PRIVATE void sqlite3Update(
   }
 
   /* Top of the update loop */
-  addr = sqlite3VdbeAddOp2(v, OP_FifoRead, regOldRowid, 0);
+  if( okOnePass ){
+    int a1 = sqlite3VdbeAddOp1(v, OP_NotNull, regOldRowid);
+    addr = sqlite3VdbeAddOp0(v, OP_Goto);
+    sqlite3VdbeJumpHere(v, a1);
+  }else{
+    addr = sqlite3VdbeAddOp2(v, OP_FifoRead, regOldRowid, 0);
+  }
 
   if( triggers_exist ){
     int regRowid;
@@ -66563,6 +74493,7 @@ SQLITE_PRIVATE void sqlite3Update(
     */
     if( chngRowid ){
       sqlite3ExprCodeAndCache(pParse, pRowidExpr, regRowid);
+      sqlite3VdbeAddOp1(v, OP_MustBeInt, regRowid);
     }else{
       sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regRowid);
     }
@@ -66587,9 +74518,10 @@ SQLITE_PRIVATE void sqlite3Update(
     sqlite3VdbeAddOp3(v, OP_MakeRecord, regCols, pTab->nCol, regRow);
     if( !isView ){
       sqlite3TableAffinityStr(v, pTab);
+      sqlite3ExprCacheAffinityChange(pParse, regCols, pTab->nCol);
     }
     sqlite3ReleaseTempRange(pParse, regCols, pTab->nCol);
-    if( pParse->nErr ) goto update_cleanup;
+    /* if( pParse->nErr ) goto update_cleanup; */
     sqlite3VdbeAddOp3(v, OP_Insert, newIdx, regRow, regRowid);
     sqlite3ReleaseTempReg(pParse, regRowid);
     sqlite3ReleaseTempReg(pParse, regRow);
@@ -66701,11 +74633,11 @@ SQLITE_PRIVATE void sqlite3Update(
 
 update_cleanup:
   sqlite3AuthContextPop(&sContext);
-  sqlite3_free(aRegIdx);
-  sqlite3_free(aXRef);
-  sqlite3SrcListDelete(pTabList);
-  sqlite3ExprListDelete(pChanges);
-  sqlite3ExprDelete(pWhere);
+  sqlite3DbFree(db, aRegIdx);
+  sqlite3DbFree(db, aXRef);
+  sqlite3SrcListDelete(db, pTabList);
+  sqlite3ExprListDelete(db, pChanges);
+  sqlite3ExprDelete(db, pWhere);
   return;
 }
 
@@ -66780,7 +74712,7 @@ static void updateVirtualTable(
   /* fill the ephemeral table 
   */
   sqlite3SelectDestInit(&dest, SRT_Table, ephemTab);
-  sqlite3Select(pParse, pSelect, &dest, 0, 0, 0, 0);
+  sqlite3Select(pParse, pSelect, &dest);
 
   /* Generate code to scan the ephemeral table and call VUpdate. */
   iReg = ++pParse->nMem;
@@ -66792,17 +74724,22 @@ static void updateVirtualTable(
   for(i=0; inCol; i++){
     sqlite3VdbeAddOp3(v, OP_Column, ephemTab, i+1+(pRowid!=0), iReg+2+i);
   }
-  pParse->pVirtualLock = pTab;
+  sqlite3VtabMakeWritable(pParse, pTab);
   sqlite3VdbeAddOp4(v, OP_VUpdate, 0, pTab->nCol+2, iReg, pVtab, P4_VTAB);
   sqlite3VdbeAddOp2(v, OP_Next, ephemTab, addr);
   sqlite3VdbeJumpHere(v, addr-1);
   sqlite3VdbeAddOp2(v, OP_Close, ephemTab, 0);
 
   /* Cleanup */
-  sqlite3SelectDelete(pSelect);  
+  sqlite3SelectDelete(db, pSelect);  
 }
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
 
+/* Make sure "isView" gets undefined in case this file becomes part of
+** the amalgamation - so that subsequent files do not see isView as a
+** macro. */
+#undef isView
+
 /************** End of update.c **********************************************/
 /************** Begin file vacuum.c ******************************************/
 /*
@@ -66821,7 +74758,7 @@ static void updateVirtualTable(
 ** Most of the code in this file may be omitted by defining the
 ** SQLITE_OMIT_VACUUM macro.
 **
-** $Id: vacuum.c,v 1.76 2008/01/03 00:01:25 drh Exp $
+** $Id: vacuum.c,v 1.83 2008/08/26 21:07:27 drh Exp $
 */
 
 #if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH)
@@ -66886,22 +74823,30 @@ SQLITE_PRIVATE void sqlite3Vacuum(Parse *pParse){
 SQLITE_PRIVATE int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){
   int rc = SQLITE_OK;     /* Return code from service routines */
   Btree *pMain;           /* The database being vacuumed */
+  Pager *pMainPager;      /* Pager for database being vacuumed */
   Btree *pTemp;           /* The temporary database we vacuum into */
   char *zSql = 0;         /* SQL statements */
   int saved_flags;        /* Saved value of the db->flags */
+  int saved_nChange;      /* Saved value of db->nChange */
+  int saved_nTotalChange; /* Saved value of db->nTotalChange */
   Db *pDb = 0;            /* Database to detach at end of vacuum */
+  int isMemDb;            /* True is vacuuming a :memory: database */
+  int nRes;
 
   /* Save the current value of the write-schema flag before setting it. */
   saved_flags = db->flags;
+  saved_nChange = db->nChange;
+  saved_nTotalChange = db->nTotalChange;
   db->flags |= SQLITE_WriteSchema | SQLITE_IgnoreChecks;
 
   if( !db->autoCommit ){
-    sqlite3SetString(pzErrMsg, "cannot VACUUM from within a transaction", 
-       (char*)0);
+    sqlite3SetString(pzErrMsg, db, "cannot VACUUM from within a transaction");
     rc = SQLITE_ERROR;
     goto end_of_vacuum;
   }
   pMain = db->aDb[0].pBt;
+  pMainPager = sqlite3BtreePager(pMain);
+  isMemDb = sqlite3PagerFile(pMainPager)->pMethods==0;
 
   /* Attach the temporary database as 'vacuum_db'. The synchronous pragma
   ** can be set to 'off' for this file, as it is not recovered if a crash
@@ -66910,6 +74855,12 @@ SQLITE_PRIVATE int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){
   ** sqlite3BtreeCopyFile() is called.
   **
   ** An optimisation would be to use a non-journaled pager.
+  ** (Later:) I tried setting "PRAGMA vacuum_db.journal_mode=OFF" but
+  ** that actually made the VACUUM run slower.  Very little journalling
+  ** actually occurs when doing a vacuum since the vacuum_db is initially
+  ** empty.  Only the journal header is written.  Apparently it takes more
+  ** time to parse and run the PRAGMA to turn journalling off than it does
+  ** to write the journal header file.
   */
   zSql = "ATTACH '' AS vacuum_db;";
   rc = execSql(db, zSql);
@@ -66917,13 +74868,27 @@ SQLITE_PRIVATE int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){
   pDb = &db->aDb[db->nDb-1];
   assert( strcmp(db->aDb[db->nDb-1].zName,"vacuum_db")==0 );
   pTemp = db->aDb[db->nDb-1].pBt;
-  sqlite3BtreeSetPageSize(pTemp, sqlite3BtreeGetPageSize(pMain),
-     sqlite3BtreeGetReserve(pMain));
-  if( db->mallocFailed ){
+
+  nRes = sqlite3BtreeGetReserve(pMain);
+
+  /* A VACUUM cannot change the pagesize of an encrypted database. */
+#ifdef SQLITE_HAS_CODEC
+  if( db->nextPagesize ){
+    extern void sqlite3CodecGetKey(sqlite3*, int, void**, int*);
+    int nKey;
+    char *zKey;
+    sqlite3CodecGetKey(db, 0, (void**)&zKey, &nKey);
+    if( nKey ) db->nextPagesize = 0;
+  }
+#endif
+
+  if( sqlite3BtreeSetPageSize(pTemp, sqlite3BtreeGetPageSize(pMain), nRes)
+   || (!isMemDb && sqlite3BtreeSetPageSize(pTemp, db->nextPagesize, nRes))
+   || db->mallocFailed 
+  ){
     rc = SQLITE_NOMEM;
     goto end_of_vacuum;
   }
-  assert( sqlite3BtreeGetPageSize(pTemp)==sqlite3BtreeGetPageSize(pMain) );
   rc = execSql(db, "PRAGMA vacuum_db.synchronous=OFF");
   if( rc!=SQLITE_OK ){
     goto end_of_vacuum;
@@ -67039,12 +75004,21 @@ SQLITE_PRIVATE int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){
     if( rc!=SQLITE_OK ) goto end_of_vacuum;
     rc = sqlite3BtreeCommit(pTemp);
     if( rc!=SQLITE_OK ) goto end_of_vacuum;
+#ifndef SQLITE_OMIT_AUTOVACUUM
+    sqlite3BtreeSetAutoVacuum(pMain, sqlite3BtreeGetAutoVacuum(pTemp));
+#endif
     rc = sqlite3BtreeCommit(pMain);
   }
 
+  if( rc==SQLITE_OK ){
+    rc = sqlite3BtreeSetPageSize(pMain, sqlite3BtreeGetPageSize(pTemp), nRes);
+  }
+
 end_of_vacuum:
   /* Restore the original value of db->flags */
   db->flags = saved_flags;
+  db->nChange = saved_nChange;
+  db->nTotalChange = saved_nTotalChange;
 
   /* Currently there is an SQL level transaction open on the vacuum
   ** database. No locks are held on any other files (since the main file
@@ -67082,7 +75056,7 @@ end_of_vacuum:
 *************************************************************************
 ** This file contains code used to help implement virtual tables.
 **
-** $Id: vtab.c,v 1.65 2008/03/06 09:58:50 mlcreech Exp $
+** $Id: vtab.c,v 1.76 2008/08/20 16:35:10 drh Exp $
 */
 #ifndef SQLITE_OMIT_VIRTUALTABLE
 
@@ -67100,17 +75074,21 @@ static int createModule(
   nName = strlen(zName);
   pMod = (Module *)sqlite3DbMallocRaw(db, sizeof(Module) + nName + 1);
   if( pMod ){
+    Module *pDel;
     char *zCopy = (char *)(&pMod[1]);
     memcpy(zCopy, zName, nName+1);
     pMod->zName = zCopy;
     pMod->pModule = pModule;
     pMod->pAux = pAux;
     pMod->xDestroy = xDestroy;
-    pMod = (Module *)sqlite3HashInsert(&db->aModule, zCopy, nName, (void*)pMod);
-    if( pMod && pMod->xDestroy ){
-      pMod->xDestroy(pMod->pAux);
+    pDel = (Module *)sqlite3HashInsert(&db->aModule, zCopy, nName, (void*)pMod);
+    if( pDel && pDel->xDestroy ){
+      pDel->xDestroy(pDel->pAux);
+    }
+    sqlite3DbFree(db, pDel);
+    if( pDel==pMod ){
+      db->mallocFailed = 1;
     }
-    sqlite3_free(pMod);
     sqlite3ResetInternalSchema(db, 0);
   }
   rc = sqlite3ApiExit(db, SQLITE_OK);
@@ -67182,17 +75160,18 @@ SQLITE_PRIVATE void sqlite3VtabUnlock(sqlite3 *db, sqlite3_vtab *pVtab){
 */
 SQLITE_PRIVATE void sqlite3VtabClear(Table *p){
   sqlite3_vtab *pVtab = p->pVtab;
+  sqlite3 *db = p->db;
   if( pVtab ){
     assert( p->pMod && p->pMod->pModule );
-    sqlite3VtabUnlock(p->pSchema->db, pVtab);
+    sqlite3VtabUnlock(db, pVtab);
     p->pVtab = 0;
   }
   if( p->azModuleArg ){
     int i;
     for(i=0; inModuleArg; i++){
-      sqlite3_free(p->azModuleArg[i]);
+      sqlite3DbFree(db, p->azModuleArg[i]);
     }
-    sqlite3_free(p->azModuleArg);
+    sqlite3DbFree(db, p->azModuleArg);
   }
 }
 
@@ -67210,10 +75189,10 @@ static void addModuleArgument(sqlite3 *db, Table *pTable, char *zArg){
   if( azModuleArg==0 ){
     int j;
     for(j=0; jazModuleArg[j]);
+      sqlite3DbFree(db, pTable->azModuleArg[j]);
     }
-    sqlite3_free(zArg);
-    sqlite3_free(pTable->azModuleArg);
+    sqlite3DbFree(db, zArg);
+    sqlite3DbFree(db, pTable->azModuleArg);
     pTable->nModuleArg = 0;
   }else{
     azModuleArg[i] = zArg;
@@ -67251,7 +75230,7 @@ SQLITE_PRIVATE void sqlite3VtabBeginParse(
   iDb = sqlite3SchemaToIndex(db, pTable->pSchema);
   assert( iDb>=0 );
 
-  pTable->isVirtual = 1;
+  pTable->tabFlags |= TF_Virtual;
   pTable->nModuleArg = 0;
   addModuleArgument(db, pTable, sqlite3NameFromToken(db, pModuleName));
   addModuleArgument(db, pTable, sqlite3DbStrDup(db, db->aDb[iDb].zName));
@@ -67344,7 +75323,7 @@ SQLITE_PRIVATE void sqlite3VtabFinishParse(Parse *pParse, Token *pEnd){
       zStmt,
       pParse->regRowid
     );
-    sqlite3_free(zStmt);
+    sqlite3DbFree(db, zStmt);
     v = sqlite3GetVdbe(pParse);
     sqlite3ChangeCookie(pParse, iDb);
 
@@ -67443,7 +75422,7 @@ static int vtabCallConstructor(
       *pzErr = sqlite3MPrintf(db, "vtable constructor failed: %s", zModuleName);
     }else {
       *pzErr = sqlite3MPrintf(db, "%s", zErr);
-      sqlite3_free(zErr);
+      sqlite3DbFree(db, zErr);
     }
   }else if( db->pVTab ){
     const char *zFormat = "vtable constructor did not declare schema: %s";
@@ -67454,7 +75433,7 @@ static int vtabCallConstructor(
     rc = rc2;
   }
   db->pVTab = 0;
-  sqlite3_free(zModuleName);
+  sqlite3DbFree(db, zModuleName);
 
   /* If everything went according to plan, loop through the columns
   ** of the table to see if any of them contain the token "hidden".
@@ -67507,7 +75486,7 @@ SQLITE_PRIVATE int sqlite3VtabCallConnect(Parse *pParse, Table *pTab){
   Module *pMod;
   int rc = SQLITE_OK;
 
-  if( !pTab || !pTab->isVirtual || pTab->pVtab ){
+  if( !pTab || (pTab->tabFlags & TF_Virtual)==0 || pTab->pVtab ){
     return SQLITE_OK;
   }
 
@@ -67523,7 +75502,7 @@ SQLITE_PRIVATE int sqlite3VtabCallConnect(Parse *pParse, Table *pTab){
     if( rc!=SQLITE_OK ){
       sqlite3ErrorMsg(pParse, "%s", zErr);
     }
-    sqlite3_free(zErr);
+    sqlite3DbFree(db, zErr);
   }
 
   return rc;
@@ -67559,7 +75538,7 @@ static int addToVTrans(sqlite3 *db, sqlite3_vtab *pVtab){
 **
 ** If an error occurs, *pzErr is set to point an an English language
 ** description of the error and an SQLITE_XXX error code is returned.
-** In this case the caller must call sqlite3_free() on *pzErr.
+** In this case the caller must call sqlite3DbFree(db, ) on *pzErr.
 */
 SQLITE_PRIVATE int sqlite3VtabCallCreate(sqlite3 *db, int iDb, const char *zTab, char **pzErr){
   int rc = SQLITE_OK;
@@ -67568,7 +75547,7 @@ SQLITE_PRIVATE int sqlite3VtabCallCreate(sqlite3 *db, int iDb, const char *zTab,
   const char *zModule;
 
   pTab = sqlite3FindTable(db, zTab, db->aDb[iDb].zName);
-  assert(pTab && pTab->isVirtual && !pTab->pVtab);
+  assert(pTab && (pTab->tabFlags & TF_Virtual)!=0 && !pTab->pVtab);
   pMod = pTab->pMod;
   zModule = pTab->azModuleArg[0];
 
@@ -67609,7 +75588,7 @@ SQLITE_API int sqlite3_declare_vtab(sqlite3 *db, const char *zCreateTable){
     sqlite3_mutex_leave(db->mutex);
     return SQLITE_MISUSE;
   }
-  assert(pTab->isVirtual && pTab->nCol==0 && pTab->aCol==0);
+  assert((pTab->tabFlags & TF_Virtual)!=0 && pTab->nCol==0 && pTab->aCol==0);
 
   memset(&sParse, 0, sizeof(Parse));
   sParse.declareVtab = 1;
@@ -67619,7 +75598,7 @@ SQLITE_API int sqlite3_declare_vtab(sqlite3 *db, const char *zCreateTable){
       SQLITE_OK == sqlite3RunParser(&sParse, zCreateTable, &zErr) && 
       sParse.pNewTable && 
       !sParse.pNewTable->pSelect && 
-      !sParse.pNewTable->isVirtual 
+      (sParse.pNewTable->tabFlags & TF_Virtual)==0
   ){
     pTab->aCol = sParse.pNewTable->aCol;
     pTab->nCol = sParse.pNewTable->nCol;
@@ -67628,7 +75607,7 @@ SQLITE_API int sqlite3_declare_vtab(sqlite3 *db, const char *zCreateTable){
     db->pVTab = 0;
   } else {
     sqlite3Error(db, SQLITE_ERROR, zErr);
-    sqlite3_free(zErr);
+    sqlite3DbFree(db, zErr);
     rc = SQLITE_ERROR;
   }
   sParse.declareVtab = 0;
@@ -67666,6 +75645,13 @@ SQLITE_PRIVATE int sqlite3VtabCallDestroy(sqlite3 *db, int iDb, const char *zTab
     }
     (void)sqlite3SafetyOn(db);
     if( rc==SQLITE_OK ){
+      int i;
+      for(i=0; inVTrans; i++){
+        if( db->aVTrans[i]==pTab->pVtab ){
+          db->aVTrans[i] = db->aVTrans[--db->nVTrans];
+          break;
+        }
+      }
       pTab->pVtab = 0;
     }
   }
@@ -67681,7 +75667,7 @@ SQLITE_PRIVATE int sqlite3VtabCallDestroy(sqlite3 *db, int iDb, const char *zTab
 **
 ** The array is cleared after invoking the callbacks. 
 */
-static void callFinaliser(sqlite3 *db, sqlite3_intptr_t offset){
+static void callFinaliser(sqlite3 *db, int offset){
   int i;
   if( db->aVTrans ){
     for(i=0; inVTrans && db->aVTrans[i]; i++){
@@ -67691,24 +75677,25 @@ static void callFinaliser(sqlite3 *db, sqlite3_intptr_t offset){
       if( x ) x(pVtab);
       sqlite3VtabUnlock(db, pVtab);
     }
-    sqlite3_free(db->aVTrans);
+    sqlite3DbFree(db, db->aVTrans);
     db->nVTrans = 0;
     db->aVTrans = 0;
   }
 }
 
 /*
-** If argument rc2 is not SQLITE_OK, then return it and do nothing. 
-** Otherwise, invoke the xSync method of all virtual tables in the 
-** sqlite3.aVTrans array. Return the error code for the first error 
-** that occurs, or SQLITE_OK if all xSync operations are successful.
+** Invoke the xSync method of all virtual tables in the sqlite3.aVTrans
+** array. Return the error code for the first error that occurs, or
+** SQLITE_OK if all xSync operations are successful.
+**
+** Set *pzErrmsg to point to a buffer that should be released using 
+** sqlite3DbFree() containing an error message, if one is available.
 */
-SQLITE_PRIVATE int sqlite3VtabSync(sqlite3 *db, int rc2){
+SQLITE_PRIVATE int sqlite3VtabSync(sqlite3 *db, char **pzErrmsg){
   int i;
   int rc = SQLITE_OK;
   int rcsafety;
   sqlite3_vtab **aVTrans = db->aVTrans;
-  if( rc2!=SQLITE_OK ) return rc2;
 
   rc = sqlite3SafetyOff(db);
   db->aVTrans = 0;
@@ -67718,6 +75705,9 @@ SQLITE_PRIVATE int sqlite3VtabSync(sqlite3 *db, int rc2){
     x = pVtab->pModule->xSync;
     if( x ){
       rc = x(pVtab);
+      sqlite3DbFree(db, *pzErrmsg);
+      *pzErrmsg = pVtab->zErrMsg;
+      pVtab->zErrMsg = 0;
     }
   }
   db->aVTrans = aVTrans;
@@ -67734,7 +75724,7 @@ SQLITE_PRIVATE int sqlite3VtabSync(sqlite3 *db, int rc2){
 ** sqlite3.aVTrans array. Then clear the array itself.
 */
 SQLITE_PRIVATE int sqlite3VtabRollback(sqlite3 *db){
-  callFinaliser(db, (sqlite3_intptr_t)(&((sqlite3_module *)0)->xRollback));
+  callFinaliser(db, offsetof(sqlite3_module,xRollback));
   return SQLITE_OK;
 }
 
@@ -67743,7 +75733,7 @@ SQLITE_PRIVATE int sqlite3VtabRollback(sqlite3 *db){
 ** sqlite3.aVTrans array. Then clear the array itself.
 */
 SQLITE_PRIVATE int sqlite3VtabCommit(sqlite3 *db){
-  callFinaliser(db, (sqlite3_intptr_t)(&((sqlite3_module *)0)->xCommit));
+  callFinaliser(db, offsetof(sqlite3_module,xCommit));
   return SQLITE_OK;
 }
 
@@ -67785,11 +75775,9 @@ SQLITE_PRIVATE int sqlite3VtabBegin(sqlite3 *db, sqlite3_vtab *pVtab){
 
     /* Invoke the xBegin method */
     rc = pModule->xBegin(pVtab);
-    if( rc!=SQLITE_OK ){
-      return rc;
+    if( rc==SQLITE_OK ){
+      rc = addToVTrans(db, pVtab);
     }
-
-    rc = addToVTrans(db, pVtab);
   }
   return rc;
 }
@@ -67829,7 +75817,7 @@ SQLITE_PRIVATE FuncDef *sqlite3VtabOverloadFunction(
   if( pExpr->op!=TK_COLUMN ) return pDef;
   pTab = pExpr->pTab;
   if( pTab==0 ) return pDef;
-  if( !pTab->isVirtual ) return pDef;
+  if( (pTab->tabFlags & TF_Virtual)==0 ) return pDef;
   pVtab = pTab->pVtab;
   assert( pVtab!=0 );
   assert( pVtab->pModule!=0 );
@@ -67845,7 +75833,12 @@ SQLITE_PRIVATE FuncDef *sqlite3VtabOverloadFunction(
       *z = sqlite3UpperToLower[*z];
     }
     rc = pMod->xFindFunction(pVtab, nArg, zLowerName, &xFunc, &pArg);
-    sqlite3_free(zLowerName);
+    sqlite3DbFree(db, zLowerName);
+    if( pVtab->zErrMsg ){
+      sqlite3Error(db, rc, "%s", pVtab->zErrMsg);
+      sqlite3DbFree(db, pVtab->zErrMsg);
+      pVtab->zErrMsg = 0;
+    }
   }
   if( rc==0 ){
     return pDef;
@@ -67858,6 +75851,7 @@ SQLITE_PRIVATE FuncDef *sqlite3VtabOverloadFunction(
     return pDef;
   }
   *pNew = *pDef;
+  pNew->zName = (char *)&pNew[1];
   memcpy(pNew->zName, pDef->zName, strlen(pDef->zName)+1);
   pNew->xFunc = xFunc;
   pNew->pUserData = pArg;
@@ -67865,6 +75859,27 @@ SQLITE_PRIVATE FuncDef *sqlite3VtabOverloadFunction(
   return pNew;
 }
 
+/*
+** Make sure virtual table pTab is contained in the pParse->apVirtualLock[]
+** array so that an OP_VBegin will get generated for it.  Add pTab to the
+** array if it is missing.  If pTab is already in the array, this routine
+** is a no-op.
+*/
+SQLITE_PRIVATE void sqlite3VtabMakeWritable(Parse *pParse, Table *pTab){
+  int i, n;
+  assert( IsVirtual(pTab) );
+  for(i=0; inVtabLock; i++){
+    if( pTab==pParse->apVtabLock[i] ) return;
+  }
+  n = (pParse->nVtabLock+1)*sizeof(pParse->apVtabLock[0]);
+  pParse->apVtabLock = sqlite3_realloc(pParse->apVtabLock, n);
+  if( pParse->apVtabLock ){
+    pParse->apVtabLock[pParse->nVtabLock++] = pTab;
+  }else{
+    pParse->db->mallocFailed = 1;
+  }
+}
+
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
 
 /************** End of vtab.c ************************************************/
@@ -67881,13 +75896,13 @@ SQLITE_PRIVATE FuncDef *sqlite3VtabOverloadFunction(
 **
 *************************************************************************
 ** This module contains C code that generates VDBE code used to process
-** the WHERE clause of SQL statements.  This module is reponsible for
+** the WHERE clause of SQL statements.  This module is responsible for
 ** generating the code that loops through a table looking for applicable
 ** rows.  Indices are selected and used to speed the search when doing
 ** so is applicable.  Because this module is responsible for selecting
 ** indices, you might also think of this module as the "query optimizer".
 **
-** $Id: where.c,v 1.290 2008/03/17 17:08:33 drh Exp $
+** $Id: where.c,v 1.326 2008/10/11 16:47:36 drh Exp $
 */
 
 /*
@@ -67900,6 +75915,8 @@ SQLITE_PRIVATE FuncDef *sqlite3VtabOverloadFunction(
 */
 #if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
 SQLITE_PRIVATE int sqlite3WhereTrace = 0;
+#endif
+#if 0
 # define WHERETRACE(X)  if(sqlite3WhereTrace) sqlite3DebugPrintf X
 #else
 # define WHERETRACE(X)
@@ -67960,7 +75977,7 @@ struct WhereTerm {
 /*
 ** Allowed values of WhereTerm.flags
 */
-#define TERM_DYNAMIC    0x01   /* Need to call sqlite3ExprDelete(pExpr) */
+#define TERM_DYNAMIC    0x01   /* Need to call sqlite3ExprDelete(db, pExpr) */
 #define TERM_VIRTUAL    0x02   /* Added by the optimizer.  Do not code */
 #define TERM_CODED      0x04   /* This term is already coded */
 #define TERM_COPIED     0x08   /* Has a child */
@@ -68071,13 +76088,14 @@ static void whereClauseInit(
 static void whereClauseClear(WhereClause *pWC){
   int i;
   WhereTerm *a;
+  sqlite3 *db = pWC->pParse->db;
   for(i=pWC->nTerm-1, a=pWC->a; i>=0; i--, a++){
     if( a->flags & TERM_DYNAMIC ){
-      sqlite3ExprDelete(a->pExpr);
+      sqlite3ExprDelete(db, a->pExpr);
     }
   }
   if( pWC->a!=pWC->aStatic ){
-    sqlite3_free(pWC->a);
+    sqlite3DbFree(db, pWC->a);
   }
 }
 
@@ -68089,7 +76107,7 @@ static void whereClauseClear(WhereClause *pWC){
 ** for freeing the expression p is assumed by the WhereClause object.
 **
 ** WARNING:  This routine might reallocate the space used to store
-** WhereTerms.  All pointers to WhereTerms should be invalided after
+** WhereTerms.  All pointers to WhereTerms should be invalidated after
 ** calling this routine.  Such pointers may be reinitialized by referencing
 ** the pWC->a[] array.
 */
@@ -68098,18 +76116,18 @@ static int whereClauseInsert(WhereClause *pWC, Expr *p, int flags){
   int idx;
   if( pWC->nTerm>=pWC->nSlot ){
     WhereTerm *pOld = pWC->a;
-    pWC->a = sqlite3_malloc( sizeof(pWC->a[0])*pWC->nSlot*2 );
+    sqlite3 *db = pWC->pParse->db;
+    pWC->a = sqlite3DbMallocRaw(db, sizeof(pWC->a[0])*pWC->nSlot*2 );
     if( pWC->a==0 ){
-      pWC->pParse->db->mallocFailed = 1;
       if( flags & TERM_DYNAMIC ){
-        sqlite3ExprDelete(p);
+        sqlite3ExprDelete(db, p);
       }
       pWC->a = pOld;
       return 0;
     }
     memcpy(pWC->a, pOld, sizeof(pWC->a[0])*pWC->nTerm);
     if( pOld!=pWC->aStatic ){
-      sqlite3_free(pOld);
+      sqlite3DbFree(db, pOld);
     }
     pWC->nSlot *= 2;
   }
@@ -68187,9 +76205,9 @@ static void createMask(ExprMaskSet *pMaskSet, int iCursor){
 ** tree.
 **
 ** In order for this routine to work, the calling function must have
-** previously invoked sqlite3ExprResolveNames() on the expression.  See
+** previously invoked sqlite3ResolveExprNames() on the expression.  See
 ** the header comment on that routine for additional information.
-** The sqlite3ExprResolveNames() routines looks for column names and
+** The sqlite3ResolveExprNames() routines looks for column names and
 ** sets their opcodes to TK_COLUMN and their Expr.iTable fields to
 ** the VDBE cursor number of the table.  This routine just has to
 ** translate the cursor numbers into bitmask values and OR all
@@ -68252,7 +76270,7 @@ static int allowedOp(int op){
 #define SWAP(TYPE,A,B) {TYPE t=A; A=B; B=t;}
 
 /*
-** Commute a comparision operator.  Expressions of the form "X op Y"
+** Commute a comparison operator.  Expressions of the form "X op Y"
 ** are converted into "Y op X".
 **
 ** If a collation sequence is associated with either the left or right
@@ -68263,10 +76281,12 @@ static int allowedOp(int op){
 ** attached to the right. For the same reason the EP_ExpCollate flag
 ** is not commuted.
 */
-static void exprCommute(Expr *pExpr){
+static void exprCommute(Parse *pParse, Expr *pExpr){
   u16 expRight = (pExpr->pRight->flags & EP_ExpCollate);
   u16 expLeft = (pExpr->pLeft->flags & EP_ExpCollate);
   assert( allowedOp(pExpr->op) && pExpr->op!=TK_IN );
+  pExpr->pRight->pColl = sqlite3ExprCollSeq(pParse, pExpr->pRight);
+  pExpr->pLeft->pColl = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
   SWAP(CollSeq*,pExpr->pRight->pColl,pExpr->pLeft->pColl);
   pExpr->pRight->flags = (pExpr->pRight->flags & ~EP_ExpCollate) | expLeft;
   pExpr->pLeft->flags = (pExpr->pLeft->flags & ~EP_ExpCollate) | expRight;
@@ -68320,13 +76340,14 @@ static WhereTerm *findTerm(
 ){
   WhereTerm *pTerm;
   int k;
+  assert( iCur>=0 );
   for(pTerm=pWC->a, k=pWC->nTerm; k; k--, pTerm++){
     if( pTerm->leftCursor==iCur
        && (pTerm->prereqRight & notReady)==0
        && pTerm->leftColumn==iColumn
        && (pTerm->eOperator & op)!=0
     ){
-      if( iCur>=0 && pIdx && pTerm->eOperator!=WO_ISNULL ){
+      if( pIdx && pTerm->eOperator!=WO_ISNULL ){
         Expr *pX = pTerm->pExpr;
         CollSeq *pColl;
         char idxaff;
@@ -68346,8 +76367,9 @@ static WhereTerm *findTerm(
           pColl = pParse->db->pDfltColl;
         }
 
-        for(j=0; jnColumn && pIdx->aiColumn[j]!=iColumn; j++){}
-        assert( jnColumn );
+        for(j=0; pIdx->aiColumn[j]!=iColumn; j++){
+          if( NEVER(j>=pIdx->nColumn) ) return 0;
+        }
         if( sqlite3StrICmp(pColl->zName, pIdx->azColl[j]) ) continue;
       }
       return pTerm;
@@ -68384,7 +76406,7 @@ static void exprAnalyzeAll(
 ** literal that does not begin with a wildcard.  
 */
 static int isLikeOrGlob(
-  sqlite3 *db,      /* The database */
+  Parse *pParse,    /* Parsing and code generating context */
   Expr *pExpr,      /* Test this expression */
   int *pnPattern,   /* Number of non-wildcard prefix characters */
   int *pisComplete, /* True if the only wildcard is % in the last character */
@@ -68396,6 +76418,7 @@ static int isLikeOrGlob(
   int c, cnt;
   char wc[3];
   CollSeq *pColl;
+  sqlite3 *db = pParse->db;
 
   if( !sqlite3IsLikeFunction(db, pExpr, pnoCase, wc) ){
     return 0;
@@ -68405,14 +76428,15 @@ static int isLikeOrGlob(
 #endif
   pList = pExpr->pList;
   pRight = pList->a[0].pExpr;
-  if( pRight->op!=TK_STRING ){
+  if( pRight->op!=TK_STRING
+   && (pRight->op!=TK_REGISTER || pRight->iColumn!=TK_STRING) ){
     return 0;
   }
   pLeft = pList->a[1].pExpr;
   if( pLeft->op!=TK_COLUMN ){
     return 0;
   }
-  pColl = pLeft->pColl;
+  pColl = sqlite3ExprCollSeq(pParse, pLeft);
   assert( pColl!=0 || pLeft->iColumn==-1 );
   if( pColl==0 ){
     /* No collation is defined for the ROWID.  Use the default. */
@@ -68490,7 +76514,7 @@ static void transferJoinMarkings(Expr *pDerived, Expr *pBase){
 **           a= OR  a= OR b=  OR ...
 **
 ** The pOrTerm input to this routine corresponds to a single term of
-** this OR clause.  In order for the term to be a condidate for
+** this OR clause.  In order for the term to be a candidate for
 ** conversion to an IN operator, the following must be true:
 **
 **     *  The left-hand side of the term must be the column which
@@ -68545,7 +76569,7 @@ static int orTermIsOptCandidate(WhereTerm *pOrTerm, int iCursor, int iColumn){
 ** This routine merely checks to see if pOrTerm has a duplicate that
 ** might qualify.  If there is a duplicate that has not yet been
 ** disqualified, then return true.  If there are no duplicates, or
-** the duplicate has also been disqualifed, return false.
+** the duplicate has also been disqualified, return false.
 */
 static int orTermHasOkDuplicate(WhereClause *pOr, WhereTerm *pOrTerm){
   if( pOrTerm->flags & TERM_COPIED ){
@@ -68587,6 +76611,7 @@ static void exprAnalyze(
   Expr *pExpr;
   Bitmask prereqLeft;
   Bitmask prereqAll;
+  Bitmask extraRight = 0;
   int nPattern;
   int isComplete;
   int noCase;
@@ -68613,7 +76638,10 @@ static void exprAnalyze(
   }
   prereqAll = exprTableUsage(pMaskSet, pExpr);
   if( ExprHasProperty(pExpr, EP_FromJoin) ){
-    prereqAll |= getMask(pMaskSet, pExpr->iRightJoinTable);
+    Bitmask x = getMask(pMaskSet, pExpr->iRightJoinTable);
+    prereqAll |= x;
+    extraRight = x-1;  /* ON clause terms may not be used with an index
+                       ** on left table of a LEFT JOIN.  Ticket #3015 */
   }
   pTerm->prereqAll = prereqAll;
   pTerm->leftCursor = -1;
@@ -68634,7 +76662,7 @@ static void exprAnalyze(
         int idxNew;
         pDup = sqlite3ExprDup(db, pExpr);
         if( db->mallocFailed ){
-          sqlite3ExprDelete(pDup);
+          sqlite3ExprDelete(db, pDup);
           return;
         }
         idxNew = whereClauseInsert(pWC, pDup, TERM_VIRTUAL|TERM_DYNAMIC);
@@ -68648,7 +76676,7 @@ static void exprAnalyze(
         pDup = pExpr;
         pNew = pTerm;
       }
-      exprCommute(pDup);
+      exprCommute(pParse, pDup);
       pLeft = pDup->pLeft;
       pNew->leftCursor = pLeft->iTable;
       pNew->leftColumn = pLeft->iColumn;
@@ -68731,7 +76759,7 @@ static void exprAnalyze(
       ExprList *pList = 0;
       Expr *pNew, *pDup;
       Expr *pLeft = 0;
-      for(i=sOr.nTerm-1, pOrTerm=sOr.a; i>=0 && ok; i--, pOrTerm++){
+      for(i=sOr.nTerm-1, pOrTerm=sOr.a; i>=0; i--, pOrTerm++){
         if( (pOrTerm->flags & TERM_OR_OK)==0 ) continue;
         pDup = sqlite3ExprDup(db, pOrTerm->pExpr->pRight);
         pList = sqlite3ExprListAppend(pWC->pParse, pList, pDup, 0);
@@ -68750,7 +76778,7 @@ static void exprAnalyze(
         pWC->a[idxNew].iParent = idxTerm;
         pTerm->nChild = 1;
       }else{
-        sqlite3ExprListDelete(pList);
+        sqlite3ExprListDelete(db, pList);
       }
     }
 or_not_possible:
@@ -68767,10 +76795,9 @@ or_not_possible:
   **          x>='abc' AND x<'abd' AND x LIKE 'abc%'
   **
   ** The last character of the prefix "abc" is incremented to form the
-  ** termination condidtion "abd".  This trick of incrementing the last
-  ** is not 255 and if the character set is not EBCDIC.  
+  ** termination condition "abd".
   */
-  if( isLikeOrGlob(db, pExpr, &nPattern, &isComplete, &noCase) ){
+  if( isLikeOrGlob(pParse, pExpr, &nPattern, &isComplete, &noCase) ){
     Expr *pLeft, *pRight;
     Expr *pStr1, *pStr2;
     Expr *pNewExpr1, *pNewExpr2;
@@ -68790,7 +76817,10 @@ or_not_possible:
       assert( pStr2->token.dyn );
       pC = (u8*)&pStr2->token.z[nPattern-1];
       c = *pC;
-      if( noCase ) c = sqlite3UpperToLower[c];
+      if( noCase ){
+        if( c=='@' ) isComplete = 0;
+        c = sqlite3UpperToLower[c];
+      }
       *pC = c + 1;
     }
     pNewExpr1 = sqlite3PExpr(pParse, TK_GE, sqlite3ExprDup(db,pLeft), pStr1, 0);
@@ -68842,6 +76872,11 @@ or_not_possible:
     }
   }
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
+
+  /* Prevent ON clause terms of a LEFT JOIN from being used to drive
+  ** an index for tables to the left of the join.
+  */
+  pTerm->prereqRight |= extraRight;
 }
 
 /*
@@ -68947,6 +76982,9 @@ static int isSortingIndex(
         ** ORDER BY term, that is OK.  Just ignore that column of the index
         */
         continue;
+      }else if( i==pIdx->nColumn ){
+        /* Index column i is the rowid.  All other terms match. */
+        break;
       }else{
         /* If an index column fails to match and is not constrained by ==
         ** then the index cannot satisfy the ORDER BY constraint.
@@ -69024,7 +77062,7 @@ static int sortableByRowid(
 /*
 ** Prepare a crude estimate of the logarithm of the input value.
 ** The results need not be exact.  This is only used for estimating
-** the total cost of performing operatings with O(logN) or O(NlogN)
+** the total cost of performing operations with O(logN) or O(NlogN)
 ** complexity.  Because N is just a guess, it is no great tragedy if
 ** logN is a little off.
 */
@@ -69109,6 +77147,7 @@ static double bestVirtualIndex(
   sqlite3_index_info **ppIdxInfo /* Index information passed to xBestIndex */
 ){
   Table *pTab = pSrc->pTab;
+  sqlite3_vtab *pVtab = pTab->pVtab;
   sqlite3_index_info *pIdxInfo;
   struct sqlite3_index_constraint *pIdxCons;
   struct sqlite3_index_orderby *pIdxOrderBy;
@@ -69132,8 +77171,10 @@ static double bestVirtualIndex(
     ** to this virtual table */
     for(i=nTerm=0, pTerm=pWC->a; inTerm; i++, pTerm++){
       if( pTerm->leftCursor != pSrc->iCursor ) continue;
-      if( pTerm->eOperator==WO_IN ) continue;
-      if( pTerm->eOperator==WO_ISNULL ) continue;
+      assert( (pTerm->eOperator&(pTerm->eOperator-1))==0 );
+      testcase( pTerm->eOperator==WO_IN );
+      testcase( pTerm->eOperator==WO_ISNULL );
+      if( pTerm->eOperator & (WO_IN|WO_ISNULL) ) continue;
       nTerm++;
     }
 
@@ -69180,8 +77221,10 @@ static double bestVirtualIndex(
 
     for(i=j=0, pTerm=pWC->a; inTerm; i++, pTerm++){
       if( pTerm->leftCursor != pSrc->iCursor ) continue;
-      if( pTerm->eOperator==WO_IN ) continue;
-      if( pTerm->eOperator==WO_ISNULL ) continue;
+      assert( (pTerm->eOperator&(pTerm->eOperator-1))==0 );
+      testcase( pTerm->eOperator==WO_IN );
+      testcase( pTerm->eOperator==WO_ISNULL );
+      if( pTerm->eOperator & (WO_IN|WO_ISNULL) ) continue;
       pIdxCons[j].iColumn = pTerm->leftColumn;
       pIdxCons[j].iTermOffset = i;
       pIdxCons[j].op = pTerm->eOperator;
@@ -69216,7 +77259,7 @@ static double bestVirtualIndex(
   ** sqlite3ViewGetColumnNames() would have picked up the error. 
   */
   assert( pTab->azModuleArg && pTab->azModuleArg[0] );
-  assert( pTab->pVtab );
+  assert( pVtab );
 #if 0
   if( pTab->pVtab==0 ){
     sqlite3ErrorMsg(pParse, "undefined module %s for table %s",
@@ -69269,10 +77312,22 @@ static double bestVirtualIndex(
   (void)sqlite3SafetyOff(pParse->db);
   WHERETRACE(("xBestIndex for %s\n", pTab->zName));
   TRACE_IDX_INPUTS(pIdxInfo);
-  rc = pTab->pVtab->pModule->xBestIndex(pTab->pVtab, pIdxInfo);
+  rc = pVtab->pModule->xBestIndex(pVtab, pIdxInfo);
   TRACE_IDX_OUTPUTS(pIdxInfo);
   (void)sqlite3SafetyOn(pParse->db);
 
+  if( rc!=SQLITE_OK ){
+    if( rc==SQLITE_NOMEM ){
+      pParse->db->mallocFailed = 1;
+    }else if( !pVtab->zErrMsg ){
+      sqlite3ErrorMsg(pParse, "%s", sqlite3ErrStr(rc));
+    }else{
+      sqlite3ErrorMsg(pParse, "%s", pVtab->zErrMsg);
+    }
+  }
+  sqlite3DbFree(pParse->db, pVtab->zErrMsg);
+  pVtab->zErrMsg = 0;
+
   for(i=0; inConstraint; i++){
     if( !pIdxInfo->aConstraint[i].usable && pUsage[i].argvIndex>0 ){
       sqlite3ErrorMsg(pParse, 
@@ -69281,15 +77336,7 @@ static double bestVirtualIndex(
     }
   }
 
-  if( rc!=SQLITE_OK ){
-    if( rc==SQLITE_NOMEM ){
-      pParse->db->mallocFailed = 1;
-    }else {
-      sqlite3ErrorMsg(pParse, "%s", sqlite3ErrStr(rc));
-    }
-  }
   *(int*)&pIdxInfo->nOrderBy = nOrderBy;
-
   return pIdxInfo->estimatedCost;
 }
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
@@ -69311,6 +77358,16 @@ static double bestVirtualIndex(
 **    *  Whether or not there must be separate lookups in the
 **       index and in the main table.
 **
+** If there was an INDEXED BY clause attached to the table in the SELECT
+** statement, then this function only considers strategies using the 
+** named index. If one cannot be found, then the returned cost is
+** SQLITE_BIG_DBL. If a strategy can be found that uses the named index, 
+** then the cost is calculated in the usual way.
+**
+** If a NOT INDEXED clause was attached to the table in the SELECT 
+** statement, then no indexes are considered. However, the selected 
+** stategy may still take advantage of the tables built-in rowid
+** index.
 */
 static double bestIndex(
   Parse *pParse,              /* The parsing context */
@@ -69335,9 +77392,12 @@ static double bestIndex(
   int eqTermMask;             /* Mask of valid equality operators */
   double cost;                /* Cost of using pProbe */
 
-  WHERETRACE(("bestIndex: tbl=%s notReady=%x\n", pSrc->pTab->zName, notReady));
+  WHERETRACE(("bestIndex: tbl=%s notReady=%llx\n", pSrc->pTab->zName, notReady));
   lowestCost = SQLITE_BIG_DBL;
   pProbe = pSrc->pTab->pIndex;
+  if( pSrc->notIndexed ){
+    pProbe = 0;
+  }
 
   /* If the table has no indices and there are no terms in the where
   ** clause that refer to the ROWID, then we will never be able to do
@@ -69354,74 +77414,77 @@ static double bestIndex(
     return 0.0;
   }
 
-  /* Check for a rowid=EXPR or rowid IN (...) constraints
-  */
-  pTerm = findTerm(pWC, iCur, -1, notReady, WO_EQ|WO_IN, 0);
-  if( pTerm ){
-    Expr *pExpr;
-    *ppIndex = 0;
-    bestFlags = WHERE_ROWID_EQ;
-    if( pTerm->eOperator & WO_EQ ){
-      /* Rowid== is always the best pick.  Look no further.  Because only
-      ** a single row is generated, output is always in sorted order */
-      *pFlags = WHERE_ROWID_EQ | WHERE_UNIQUE;
-      *pnEq = 1;
-      WHERETRACE(("... best is rowid\n"));
-      return 0.0;
-    }else if( (pExpr = pTerm->pExpr)->pList!=0 ){
-      /* Rowid IN (LIST): cost is NlogN where N is the number of list
-      ** elements.  */
-      lowestCost = pExpr->pList->nExpr;
-      lowestCost *= estLog(lowestCost);
-    }else{
-      /* Rowid IN (SELECT): cost is NlogN where N is the number of rows
-      ** in the result of the inner select.  We have no way to estimate
-      ** that value so make a wild guess. */
-      lowestCost = 200;
-    }
-    WHERETRACE(("... rowid IN cost: %.9g\n", lowestCost));
-  }
-
-  /* Estimate the cost of a table scan.  If we do not know how many
-  ** entries are in the table, use 1 million as a guess.
-  */
-  cost = pProbe ? pProbe->aiRowEst[0] : 1000000;
-  WHERETRACE(("... table scan base cost: %.9g\n", cost));
-  flags = WHERE_ROWID_RANGE;
-
-  /* Check for constraints on a range of rowids in a table scan.
-  */
-  pTerm = findTerm(pWC, iCur, -1, notReady, WO_LT|WO_LE|WO_GT|WO_GE, 0);
-  if( pTerm ){
-    if( findTerm(pWC, iCur, -1, notReady, WO_LT|WO_LE, 0) ){
-      flags |= WHERE_TOP_LIMIT;
-      cost /= 3;  /* Guess that rowidEXPR eliminates two-thirds of rows */
+  /* Check for a rowid=EXPR or rowid IN (...) constraints. If there was
+  ** an INDEXED BY clause attached to this table, skip this step.
+  */
+  if( !pSrc->pIndex ){
+    pTerm = findTerm(pWC, iCur, -1, notReady, WO_EQ|WO_IN, 0);
+    if( pTerm ){
+      Expr *pExpr;
+      *ppIndex = 0;
+      bestFlags = WHERE_ROWID_EQ;
+      if( pTerm->eOperator & WO_EQ ){
+        /* Rowid== is always the best pick.  Look no further.  Because only
+        ** a single row is generated, output is always in sorted order */
+        *pFlags = WHERE_ROWID_EQ | WHERE_UNIQUE;
+        *pnEq = 1;
+        WHERETRACE(("... best is rowid\n"));
+        return 0.0;
+      }else if( (pExpr = pTerm->pExpr)->pList!=0 ){
+        /* Rowid IN (LIST): cost is NlogN where N is the number of list
+        ** elements.  */
+        lowestCost = pExpr->pList->nExpr;
+        lowestCost *= estLog(lowestCost);
+      }else{
+        /* Rowid IN (SELECT): cost is NlogN where N is the number of rows
+        ** in the result of the inner select.  We have no way to estimate
+        ** that value so make a wild guess. */
+        lowestCost = 200;
+      }
+      WHERETRACE(("... rowid IN cost: %.9g\n", lowestCost));
     }
-    WHERETRACE(("... rowid range reduces cost to %.9g\n", cost));
-  }else{
-    flags = 0;
-  }
-
-  /* If the table scan does not satisfy the ORDER BY clause, increase
-  ** the cost by NlogN to cover the expense of sorting. */
-  if( pOrderBy ){
-    if( sortableByRowid(iCur, pOrderBy, pWC->pMaskSet, &rev) ){
-      flags |= WHERE_ORDERBY|WHERE_ROWID_RANGE;
-      if( rev ){
-        flags |= WHERE_REVERSE;
+  
+    /* Estimate the cost of a table scan.  If we do not know how many
+    ** entries are in the table, use 1 million as a guess.
+    */
+    cost = pProbe ? pProbe->aiRowEst[0] : 1000000;
+    WHERETRACE(("... table scan base cost: %.9g\n", cost));
+    flags = WHERE_ROWID_RANGE;
+  
+    /* Check for constraints on a range of rowids in a table scan.
+    */
+    pTerm = findTerm(pWC, iCur, -1, notReady, WO_LT|WO_LE|WO_GT|WO_GE, 0);
+    if( pTerm ){
+      if( findTerm(pWC, iCur, -1, notReady, WO_LT|WO_LE, 0) ){
+        flags |= WHERE_TOP_LIMIT;
+        cost /= 3;  /* Guess that rowidEXPR eliminates two-thirds of rows */
+      }
+      WHERETRACE(("... rowid range reduces cost to %.9g\n", cost));
     }else{
-      cost += cost*estLog(cost);
-      WHERETRACE(("... sorting increases cost to %.9g\n", cost));
+      flags = 0;
+    }
+  
+    /* If the table scan does not satisfy the ORDER BY clause, increase
+    ** the cost by NlogN to cover the expense of sorting. */
+    if( pOrderBy ){
+      if( sortableByRowid(iCur, pOrderBy, pWC->pMaskSet, &rev) ){
+        flags |= WHERE_ORDERBY|WHERE_ROWID_RANGE;
+        if( rev ){
+          flags |= WHERE_REVERSE;
+        }
+      }else{
+        cost += cost*estLog(cost);
+        WHERETRACE(("... sorting increases cost to %.9g\n", cost));
+      }
+    }
+    if( costpNext){
+  if( pSrc->pIndex ){
+    pProbe = pSrc->pIndex;
+  }
+  for(; pProbe; pProbe=(pSrc->pIndex ? 0 : pProbe->pNext)){
     int i;                       /* Loop counter */
     double inMultiplier = 1;
 
@@ -69457,7 +77523,7 @@ static double bestIndex(
         flags |= WHERE_COLUMN_IN;
         if( pExpr->pSelect!=0 ){
           inMultiplier *= 25;
-        }else if( pExpr->pList!=0 ){
+        }else if( ALWAYS(pExpr->pList) ){
           inMultiplier *= pExpr->pList->nExpr + 1;
         }
       }
@@ -69573,7 +77639,7 @@ static double bestIndex(
 */
 static void disableTerm(WhereLevel *pLevel, WhereTerm *pTerm){
   if( pTerm
-      && (pTerm->flags & TERM_CODED)==0
+      && ALWAYS((pTerm->flags & TERM_CODED)==0)
       && (pLevel->iLeftJoin==0 || ExprHasProperty(pTerm->pExpr, EP_FromJoin))
   ){
     pTerm->flags |= TERM_CODED;
@@ -69587,24 +77653,17 @@ static void disableTerm(WhereLevel *pLevel, WhereTerm *pTerm){
 }
 
 /*
-** Generate code that builds a probe for an index.
-**
-** There should be nColumn values on the stack.  The index
-** to be probed is pIdx.  Pop the values from the stack and
-** replace them all with a single record that is the index
-** problem.
+** Apply the affinities associated with the first n columns of index
+** pIdx to the values in the n registers starting at base.
 */
-static void buildIndexProbe(
-  Vdbe *v,        /* Generate code into this VM */
-  int nColumn,    /* The number of columns to check for NULL */
-  Index *pIdx,    /* Index that we will be searching */
-  int regSrc,     /* Take values from this register */
-  int regDest     /* Write the result into this register */
-){
-  assert( regSrc>0 );
-  assert( regDest>0 );
-  sqlite3VdbeAddOp3(v, OP_MakeRecord, regSrc, nColumn, regDest);
-  sqlite3IndexAffinityStr(v, pIdx);
+static void codeApplyAffinity(Parse *pParse, int base, int n, Index *pIdx){
+  if( n>0 ){
+    Vdbe *v = pParse->pVdbe;
+    assert( v!=0 );
+    sqlite3VdbeAddOp2(v, OP_Affinity, base, n);
+    sqlite3IndexAffinityStr(v, pIdx);
+    sqlite3ExprCacheAffinityChange(pParse, base, n);
+  }
 }
 
 
@@ -69619,19 +77678,21 @@ static void buildIndexProbe(
 ** result is left on the stack.  For constraints of the form X IN (...)
 ** this routine sets up a loop that will iterate over all values of X.
 */
-static void codeEqualityTerm(
+static int codeEqualityTerm(
   Parse *pParse,      /* The parsing context */
   WhereTerm *pTerm,   /* The term of the WHERE clause to be coded */
   WhereLevel *pLevel, /* When level of the FROM clause we are working on */
-  int iReg            /* Leave results in this register */
+  int iTarget         /* Attempt to leave results in this register */
 ){
   Expr *pX = pTerm->pExpr;
   Vdbe *v = pParse->pVdbe;
+  int iReg;                  /* Register holding results */
 
-  assert( iReg>0 && iReg<=pParse->nMem );
+  assert( iTarget>0 );
   if( pX->op==TK_EQ ){
-    sqlite3ExprCode(pParse, pX->pRight, iReg);
+    iReg = sqlite3ExprCodeTarget(pParse, pX->pRight, iTarget);
   }else if( pX->op==TK_ISNULL ){
+    iReg = iTarget;
     sqlite3VdbeAddOp2(v, OP_Null, 0, iReg);
 #ifndef SQLITE_OMIT_SUBQUERY
   }else{
@@ -69640,7 +77701,8 @@ static void codeEqualityTerm(
     struct InLoop *pIn;
 
     assert( pX->op==TK_IN );
-    eType = sqlite3FindInIndex(pParse, pX, 1);
+    iReg = iTarget;
+    eType = sqlite3FindInIndex(pParse, pX, 0);
     iTab = pX->iTable;
     sqlite3VdbeAddOp2(v, OP_Rewind, iTab, 0);
     VdbeComment((v, "%.*s", pX->span.n, pX->span.z));
@@ -69666,6 +77728,7 @@ static void codeEqualityTerm(
 #endif
   }
   disableTerm(pLevel, pTerm);
+  return iReg;
 }
 
 /*
@@ -69719,11 +77782,17 @@ static int codeAllEqualityTerms(
   */
   assert( pIdx->nColumn>=nEq );
   for(j=0; jaiColumn[j];
     pTerm = findTerm(pWC, iCur, k, notReady, pLevel->flags, pIdx);
-    if( pTerm==0 ) break;
+    if( NEVER(pTerm==0) ) break;
     assert( (pTerm->flags & TERM_CODED)==0 );
-    codeEqualityTerm(pParse, pTerm, pLevel, regBase+j);
+    r1 = codeEqualityTerm(pParse, pTerm, pLevel, regBase+j);
+    if( r1!=regBase+j ){
+      sqlite3VdbeAddOp2(v, OP_SCopy, r1, regBase+j);
+    }
+    testcase( pTerm->eOperator & WO_ISNULL );
+    testcase( pTerm->eOperator & WO_IN );
     if( (pTerm->eOperator & (WO_ISNULL|WO_IN))==0 ){
       sqlite3VdbeAddOp2(v, OP_IsNull, regBase+j, pLevel->brk);
     }
@@ -69747,17 +77816,17 @@ static int nQPlan = 0;              /* Next free slow in _query_plan[] */
 /*
 ** Free a WhereInfo structure
 */
-static void whereInfoFree(WhereInfo *pWInfo){
+static void whereInfoFree(sqlite3 *db, WhereInfo *pWInfo){
   if( pWInfo ){
     int i;
     for(i=0; inLevel; i++){
       sqlite3_index_info *pInfo = pWInfo->a[i].pIdxInfo;
       if( pInfo ){
         assert( pInfo->needToFreeIdxStr==0 );
-        sqlite3_free(pInfo);
+        sqlite3DbFree(db, pInfo);
       }
     }
-    sqlite3_free(pWInfo);
+    sqlite3DbFree(db, pWInfo);
   }
 }
 
@@ -69855,7 +77924,7 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
   SrcList *pTabList,    /* A list of all tables to be scanned */
   Expr *pWhere,         /* The WHERE clause */
   ExprList **ppOrderBy, /* An ORDER BY clause, or NULL */
-  u8 obflag             /* One of ORDERBY_MIN, ORDERBY_MAX or ORDERBY_NORMAL */
+  u8 wflags             /* One of the WHERE_* flags defined in sqliteInt.h */
 ){
   int i;                     /* Loop counter */
   WhereInfo *pWInfo;         /* Will become the return value of this function */
@@ -69889,6 +77958,7 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
   */
   initMaskSet(&maskSet);
   whereClauseInit(&wc, pParse, &maskSet);
+  sqlite3ExprCodeConstants(pParse, pWhere);
   whereSplit(&wc, pWhere, TK_AND);
     
   /* Allocate and initialize the WhereInfo structure that will become the
@@ -69898,7 +77968,7 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
   pWInfo = sqlite3DbMallocZero(db,  
                       sizeof(WhereInfo) + pTabList->nSrc*sizeof(WhereLevel));
   if( db->mallocFailed ){
-    goto whereBeginNoMem;
+    goto whereBeginError;
   }
   pWInfo->nLevel = pTabList->nSrc;
   pWInfo->pParse = pParse;
@@ -69913,17 +77983,39 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
     pWhere = 0;
   }
 
+  /* Assign a bit from the bitmask to every term in the FROM clause.
+  **
+  ** When assigning bitmask values to FROM clause cursors, it must be
+  ** the case that if X is the bitmask for the N-th FROM clause term then
+  ** the bitmask for all FROM clause terms to the left of the N-th term
+  ** is (X-1).   An expression from the ON clause of a LEFT JOIN can use
+  ** its Expr.iRightJoinTable value to find the bitmask of the right table
+  ** of the join.  Subtracting one from the right table bitmask gives a
+  ** bitmask for all tables to the left of the join.  Knowing the bitmask
+  ** for all tables to the left of a left join is important.  Ticket #3015.
+  */
+  for(i=0; inSrc; i++){
+    createMask(&maskSet, pTabList->a[i].iCursor);
+  }
+#ifndef NDEBUG
+  {
+    Bitmask toTheLeft = 0;
+    for(i=0; inSrc; i++){
+      Bitmask m = getMask(&maskSet, pTabList->a[i].iCursor);
+      assert( (m-1)==toTheLeft );
+      toTheLeft |= m;
+    }
+  }
+#endif
+
   /* Analyze all of the subexpressions.  Note that exprAnalyze() might
   ** add new virtual terms onto the end of the WHERE clause.  We do not
   ** want to analyze these virtual terms, so start analyzing at the end
   ** and work forward so that the added virtual terms are never processed.
   */
-  for(i=0; inSrc; i++){
-    createMask(&maskSet, pTabList->a[i].iCursor);
-  }
   exprAnalyzeAll(pTabList, &wc);
   if( db->mallocFailed ){
-    goto whereBeginNoMem;
+    goto whereBeginError;
   }
 
   /* Chose the best index to use for each table in the FROM clause.
@@ -69933,7 +78025,7 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
   **   pWInfo->a[].pIdx      The index to use for this level of the loop.
   **   pWInfo->a[].flags     WHERE_xxx flags associated with pIdx
   **   pWInfo->a[].nEq       The number of == and IN constraints
-  **   pWInfo->a[].iFrom     When term of the FROM clause is being coded
+  **   pWInfo->a[].iFrom     Which term of the FROM clause is being coded
   **   pWInfo->a[].iTabCur   The VDBE cursor for the database table
   **   pWInfo->a[].iIdxCur   The VDBE cursor for the index
   **
@@ -70012,7 +78104,7 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
       }
       if( doNotReorder ) break;
     }
-    WHERETRACE(("*** Optimizer choose table %d for loop %d\n", bestJ,
+    WHERETRACE(("*** Optimizer selects table %d for loop %d\n", bestJ,
            pLevel-pWInfo->a));
     if( (bestFlags & WHERE_ORDERBY)!=0 ){
       *ppOrderBy = 0;
@@ -70030,6 +78122,18 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
     }
     notReady &= ~getMask(&maskSet, pTabList->a[bestJ].iCursor);
     pLevel->iFrom = bestJ;
+
+    /* Check that if the table scanned by this loop iteration had an
+    ** INDEXED BY clause attached to it, that the named index is being
+    ** used for the scan. If not, then query compilation has failed.
+    ** Return an error.
+    */
+    pIdx = pTabList->a[bestJ].pIndex;
+    assert( !pIdx || !pBest || pIdx==pBest );
+    if( pIdx && pBest!=pIdx ){
+      sqlite3ErrorMsg(pParse, "cannot use index: %s", pIdx->zName);
+      goto whereBeginError;
+    }
   }
   WHERETRACE(("*** Optimizer Finished ***\n"));
 
@@ -70040,6 +78144,17 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
     *ppOrderBy = 0;
   }
 
+  /* If the caller is an UPDATE or DELETE statement that is requesting
+  ** to use a one-pass algorithm, determine if this is appropriate.
+  ** The one-pass algorithm only works if the WHERE clause constraints
+  ** the statement to update a single row.
+  */
+  assert( (wflags & WHERE_ONEPASS_DESIRED)==0 || pWInfo->nLevel==1 );
+  if( (wflags & WHERE_ONEPASS_DESIRED)!=0 && (andFlags & WHERE_UNIQUE)!=0 ){
+    pWInfo->okOnePass = 1;
+    pWInfo->a[0].flags &= ~WHERE_IDX_ONLY;
+  }
+
   /* Open all tables in the pTabList and any indices selected for
   ** searching those tables.
   */
@@ -70056,22 +78171,22 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
       struct SrcList_item *pItem = &pTabList->a[pLevel->iFrom];
       zMsg = sqlite3MPrintf(db, "TABLE %s", pItem->zName);
       if( pItem->zAlias ){
-        zMsg = sqlite3MPrintf(db, "%z AS %s", zMsg, pItem->zAlias);
+        zMsg = sqlite3MAppendf(db, zMsg, "%s AS %s", zMsg, pItem->zAlias);
       }
       if( (pIx = pLevel->pIdx)!=0 ){
-        zMsg = sqlite3MPrintf(db, "%z WITH INDEX %s", zMsg, pIx->zName);
+        zMsg = sqlite3MAppendf(db, zMsg, "%s WITH INDEX %s", zMsg, pIx->zName);
       }else if( pLevel->flags & (WHERE_ROWID_EQ|WHERE_ROWID_RANGE) ){
-        zMsg = sqlite3MPrintf(db, "%z USING PRIMARY KEY", zMsg);
+        zMsg = sqlite3MAppendf(db, zMsg, "%s USING PRIMARY KEY", zMsg);
       }
 #ifndef SQLITE_OMIT_VIRTUALTABLE
       else if( pLevel->pBestIdx ){
         sqlite3_index_info *pBestIdx = pLevel->pBestIdx;
-        zMsg = sqlite3MPrintf(db, "%z VIRTUAL TABLE INDEX %d:%s", zMsg,
+        zMsg = sqlite3MAppendf(db, zMsg, "%s VIRTUAL TABLE INDEX %d:%s", zMsg,
                     pBestIdx->idxNum, pBestIdx->idxStr);
       }
 #endif
       if( pLevel->flags & WHERE_ORDERBY ){
-        zMsg = sqlite3MPrintf(db, "%z ORDER BY", zMsg);
+        zMsg = sqlite3MAppendf(db, zMsg, "%s ORDER BY", zMsg);
       }
       sqlite3VdbeAddOp4(v, OP_Explain, i, pLevel->iFrom, 0, zMsg, P4_DYNAMIC);
     }
@@ -70079,7 +78194,7 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
     pTabItem = &pTabList->a[pLevel->iFrom];
     pTab = pTabItem->pTab;
     iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
-    if( pTab->isEphem || pTab->pSelect ) continue;
+    if( (pTab->tabFlags & TF_Ephemeral)!=0 || pTab->pSelect ) continue;
 #ifndef SQLITE_OMIT_VIRTUALTABLE
     if( pLevel->pBestIdx ){
       int iCur = pTabItem->iCursor;
@@ -70088,12 +78203,13 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
     }else
 #endif
     if( (pLevel->flags & WHERE_IDX_ONLY)==0 ){
-      sqlite3OpenTable(pParse, pTabItem->iCursor, iDb, pTab, OP_OpenRead);
-      if( pTab->nCol<(sizeof(Bitmask)*8) ){
+      int op = pWInfo->okOnePass ? OP_OpenWrite : OP_OpenRead;
+      sqlite3OpenTable(pParse, pTabItem->iCursor, iDb, pTab, op);
+      if( !pWInfo->okOnePass && pTab->nCol<(sizeof(Bitmask)*8) ){
         Bitmask b = pTabItem->colUsed;
         int n = 0;
         for(; b; b=b>>1, n++){}
-        sqlite3VdbeChangeP2(v, sqlite3VdbeCurrentAddr(v)-1, n);
+        sqlite3VdbeChangeP2(v, sqlite3VdbeCurrentAddr(v)-2, n);
         assert( n<=pTab->nCol );
       }
     }else{
@@ -70103,10 +78219,10 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
     if( (pIx = pLevel->pIdx)!=0 ){
       KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIx);
       assert( pIx->pSchema==pTab->pSchema );
+      sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pIx->nColumn+1);
       sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIx->tnum, iDb,
                         (char*)pKey, P4_KEYINFO_HANDOFF);
       VdbeComment((v, "%s", pIx->zName));
-      sqlite3VdbeAddOp2(v, OP_SetNumColumns, iIdxCur, pIx->nColumn+1);
     }
     sqlite3CodeVerifySchema(pParse, iDb);
   }
@@ -70171,24 +78287,28 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
                                                   pBestIdx->aConstraint;
 
       iReg = sqlite3GetTempRange(pParse, nConstraint+2);
+      pParse->disableColCache++;
       for(j=1; j<=nConstraint; j++){
         int k;
         for(k=0; kdisableColCache );
             sqlite3ExprCode(pParse, wc.a[iTerm].pExpr->pRight, iReg+j+1);
             break;
           }
         }
         if( k==nConstraint ) break;
       }
+      assert( pParse->disableColCache );
+      pParse->disableColCache--;
       sqlite3VdbeAddOp2(v, OP_Integer, pBestIdx->idxNum, iReg);
       sqlite3VdbeAddOp2(v, OP_Integer, j-1, iReg+1);
       sqlite3VdbeAddOp4(v, OP_VFilter, iCur, brk, iReg, pBestIdx->idxStr,
                         pBestIdx->needToFreeIdxStr ? P4_MPRINTF : P4_STATIC);
       sqlite3ReleaseTempRange(pParse, iReg, nConstraint+2);
       pBestIdx->needToFreeIdxStr = 0;
-      for(j=0; jnConstraint; j++){
+      for(j=0; jpExpr!=0 );
       assert( pTerm->leftCursor==iCur );
       assert( omitTable==0 );
-      r1 = sqlite3GetTempReg(pParse);
-      codeEqualityTerm(pParse, pTerm, pLevel, r1);
+      r1 = codeEqualityTerm(pParse, pTerm, pLevel, rtmp);
       nxt = pLevel->nxt;
-      sqlite3VdbeAddOp3(v, OP_MustBeInt, r1, nxt, 1);
+      sqlite3VdbeAddOp2(v, OP_MustBeInt, r1, nxt);
       sqlite3VdbeAddOp3(v, OP_NotExists, iCur, nxt, r1);
+      sqlite3ReleaseTempReg(pParse, rtmp);
       VdbeComment((v, "pk"));
-      sqlite3ReleaseTempReg(pParse, r1);
       pLevel->op = OP_Noop;
     }else if( pLevel->flags & WHERE_ROWID_RANGE ){
       /* Case 2:  We have an inequality comparison against the ROWID field.
@@ -70277,48 +78397,72 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
         sqlite3VdbeChangeP5(v, SQLITE_AFF_NUMERIC | SQLITE_JUMPIFNULL);
         sqlite3ReleaseTempReg(pParse, r1);
       }
-    }else if( pLevel->flags & WHERE_COLUMN_RANGE ){
-      /* Case 3: The WHERE clause term that refers to the right-most
-      **         column of the index is an inequality.  For example, if
-      **         the index is on (x,y,z) and the WHERE clause is of the
-      **         form "x=5 AND y<10" then this case is used.  Only the
-      **         right-most column can be an inequality - the rest must
-      **         use the "==" and "IN" operators.
+    }else if( pLevel->flags & (WHERE_COLUMN_RANGE|WHERE_COLUMN_EQ) ){
+      /* Case 3: A scan using an index.
+      **
+      **         The WHERE clause may contain zero or more equality 
+      **         terms ("==" or "IN" operators) that refer to the N
+      **         left-most columns of the index. It may also contain
+      **         inequality constraints (>, <, >= or <=) on the indexed
+      **         column that immediately follows the N equalities. Only 
+      **         the right-most column can be an inequality - the rest must
+      **         use the "==" and "IN" operators. For example, if the 
+      **         index is on (x,y,z), then the following clauses are all 
+      **         optimized:
+      **
+      **            x=5
+      **            x=5 AND y=10
+      **            x=5 AND y<10
+      **            x=5 AND y>5 AND y<10
+      **            x=5 AND y=5 AND z<=10
+      **
+      **         The z<10 term of the following cannot be used, only
+      **         the x=5 term:
+      **
+      **            x=5 AND z<10
+      **
+      **         N may be zero if there are inequality constraints.
+      **         If there are no inequality constraints, then N is at
+      **         least one.
       **
       **         This case is also used when there are no WHERE clause
       **         constraints but an index is selected anyway, in order
       **         to force the output order to conform to an ORDER BY.
-      */
-      int start;
+      */  
+      int aStartOp[] = {
+        0,
+        0,
+        OP_Rewind,           /* 2: (!start_constraints && startEq &&  !bRev) */
+        OP_Last,             /* 3: (!start_constraints && startEq &&   bRev) */
+        OP_MoveGt,           /* 4: (start_constraints  && !startEq && !bRev) */
+        OP_MoveLt,           /* 5: (start_constraints  && !startEq &&  bRev) */
+        OP_MoveGe,           /* 6: (start_constraints  &&  startEq && !bRev) */
+        OP_MoveLe            /* 7: (start_constraints  &&  startEq &&  bRev) */
+      };
+      int aEndOp[] = {
+        OP_Noop,             /* 0: (!end_constraints) */
+        OP_IdxGE,            /* 1: (end_constraints && !bRev) */
+        OP_IdxLT             /* 2: (end_constraints && bRev) */
+      };
       int nEq = pLevel->nEq;
-      int topEq=0;        /* True if top limit uses ==. False is strictly < */
-      int btmEq=0;        /* True if btm limit uses ==. False if strictly > */
-      int topOp, btmOp;   /* Operators for the top and bottom search bounds */
-      int testOp;
-      int topLimit = (pLevel->flags & WHERE_TOP_LIMIT)!=0;
-      int btmLimit = (pLevel->flags & WHERE_BTM_LIMIT)!=0;
-      int isMinQuery = 0;      /* If this is an optimized SELECT min(x) ... */
-      int regBase;        /* Base register holding constraint values */
-      int r1;             /* Temp register */
+      int isMinQuery = 0;          /* If this is an optimized SELECT min(x).. */
+      int regBase;                 /* Base register holding constraint values */
+      int r1;                      /* Temp register */
+      WhereTerm *pRangeStart = 0;  /* Inequality constraint at range start */
+      WhereTerm *pRangeEnd = 0;    /* Inequality constraint at range end */
+      int startEq;                 /* True if range start uses ==, >= or <= */
+      int endEq;                   /* True if range end uses ==, >= or <= */
+      int start_constraints;       /* Start of range is constrained */
+      int k = pIdx->aiColumn[nEq]; /* Column for inequality constraints */
+      int nConstraint;             /* Number of constraint terms */
+      int op;
 
       /* Generate code to evaluate all constraint terms using == or IN
-      ** and level the values of those terms on the stack.
+      ** and store the values of those terms in an array of registers
+      ** starting at regBase.
       */
       regBase = codeAllEqualityTerms(pParse, pLevel, &wc, notReady, 2);
-
-      /* Figure out what comparison operators to use for top and bottom 
-      ** search bounds. For an ascending index, the bottom bound is a > or >=
-      ** operator and the top bound is a < or <= operator.  For a descending
-      ** index the operators are reversed.
-      */
-      if( pIdx->aSortOrder[nEq]==SQLITE_SO_ASC ){
-        topOp = WO_LT|WO_LE;
-        btmOp = WO_GT|WO_GE;
-      }else{
-        topOp = WO_GT|WO_GE;
-        btmOp = WO_LT|WO_LE;
-        SWAP(int, topLimit, btmLimit);
-      }
+      nxt = pLevel->nxt;
 
       /* If this loop satisfies a sort order (pOrderBy) request that 
       ** was passed to this function to implement a "SELECT min(x) ..." 
@@ -70328,202 +78472,121 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
       ** the first one after the nEq equality constraints in the index,
       ** this requires some special handling.
       */
-      if( (obflag==ORDERBY_MIN)
+      if( (wflags&WHERE_ORDERBY_MIN)!=0
        && (pLevel->flags&WHERE_ORDERBY)
        && (pIdx->nColumn>nEq)
-       && (pOrderBy->a[0].pExpr->iColumn==pIdx->aiColumn[nEq])
       ){
+        assert( pOrderBy->nExpr==1 );
+        assert( pOrderBy->a[0].pExpr->iColumn==pIdx->aiColumn[nEq] );
         isMinQuery = 1;
       }
 
-      /* Generate the termination key.  This is the key value that
-      ** will end the search.  There is no termination key if there
-      ** are no equality terms and no "X<..." term.
-      **
-      ** 2002-Dec-04: On a reverse-order scan, the so-called "termination"
-      ** key computed here really ends up being the start key.
+      /* Find any inequality constraint terms for the start and end 
+      ** of the range. 
       */
-      nxt = pLevel->nxt;
-      if( topLimit ){
-        Expr *pX;
-        int k = pIdx->aiColumn[nEq];
-        pTerm = findTerm(&wc, iCur, k, notReady, topOp, pIdx);
-        assert( pTerm!=0 );
-        pX = pTerm->pExpr;
-        assert( (pTerm->flags & TERM_CODED)==0 );
-        sqlite3ExprCode(pParse, pX->pRight, regBase+nEq);
-        sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, nxt);
-        topEq = pTerm->eOperator & (WO_LE|WO_GE);
-        disableTerm(pLevel, pTerm);
-        testOp = OP_IdxGE;
-      }else{
-        testOp = nEq>0 ? OP_IdxGE : OP_Noop;
-        topEq = 1;
-      }
-      if( testOp!=OP_Noop || (isMinQuery&&bRev) ){
-        int nCol = nEq + topLimit;
-        if( isMinQuery && !topLimit ){
-          sqlite3VdbeAddOp2(v, OP_Null, 0, regBase+nCol);
-          nCol++;
-          topEq = 0;
-        }
-        buildIndexProbe(v, nCol, pIdx, regBase, pLevel->iMem);
-        if( bRev ){
-          int op = topEq ? OP_MoveLe : OP_MoveLt;
-          sqlite3VdbeAddOp3(v, op, iIdxCur, nxt, pLevel->iMem);
-        }
-      }else if( bRev ){
-        sqlite3VdbeAddOp2(v, OP_Last, iIdxCur, brk);
+      if( pLevel->flags & WHERE_TOP_LIMIT ){
+        pRangeEnd = findTerm(&wc, iCur, k, notReady, (WO_LT|WO_LE), pIdx);
       }
-   
-      /* Generate the start key.  This is the key that defines the lower
-      ** bound on the search.  There is no start key if there are no
-      ** equality terms and if there is no "X>..." term.  In
-      ** that case, generate a "Rewind" instruction in place of the
-      ** start key search.
-      **
-      ** 2002-Dec-04: In the case of a reverse-order search, the so-called
-      ** "start" key really ends up being used as the termination key.
-      */
-      if( btmLimit ){
-        Expr *pX;
-        int k = pIdx->aiColumn[nEq];
-        pTerm = findTerm(&wc, iCur, k, notReady, btmOp, pIdx);
-        assert( pTerm!=0 );
-        pX = pTerm->pExpr;
-        assert( (pTerm->flags & TERM_CODED)==0 );
-        sqlite3ExprCode(pParse, pX->pRight, regBase+nEq);
-        sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, nxt);
-        btmEq = pTerm->eOperator & (WO_LE|WO_GE);
-        disableTerm(pLevel, pTerm);
-      }else{
-        btmEq = 1;
-      }
-      if( nEq>0 || btmLimit || (isMinQuery&&!bRev) ){
-        int nCol = nEq + btmLimit;
-        if( isMinQuery && !btmLimit ){
-          sqlite3VdbeAddOp2(v, OP_Null, 0, regBase+nCol);
-          nCol++;
-          btmEq = 0;
-        }
-        if( bRev ){
-          r1 = pLevel->iMem;
-          testOp = OP_IdxLT;
-        }else{
-          r1 = sqlite3GetTempReg(pParse);
-        }
-        buildIndexProbe(v, nCol, pIdx, regBase, r1);
-        if( !bRev ){
-          int op = btmEq ? OP_MoveGe : OP_MoveGt;
-          sqlite3VdbeAddOp3(v, op, iIdxCur, nxt, r1);
-          sqlite3ReleaseTempReg(pParse, r1);
-        }
-      }else if( bRev ){
-        testOp = OP_Noop;
-      }else{
-        sqlite3VdbeAddOp2(v, OP_Rewind, iIdxCur, brk);
+      if( pLevel->flags & WHERE_BTM_LIMIT ){
+        pRangeStart = findTerm(&wc, iCur, k, notReady, (WO_GT|WO_GE), pIdx);
       }
 
-      /* Generate the the top of the loop.  If there is a termination
-      ** key we have to test for that key and abort at the top of the
-      ** loop.
+      /* If we are doing a reverse order scan on an ascending index, or
+      ** a forward order scan on a descending index, interchange the 
+      ** start and end terms (pRangeStart and pRangeEnd).
       */
-      start = sqlite3VdbeCurrentAddr(v);
-      if( testOp!=OP_Noop ){
-        sqlite3VdbeAddOp3(v, testOp, iIdxCur, nxt, pLevel->iMem);
-        if( (topEq && !bRev) || (!btmEq && bRev) ){
-          sqlite3VdbeChangeP5(v, 1);
+      if( bRev==(pIdx->aSortOrder[nEq]==SQLITE_SO_ASC) ){
+        SWAP(WhereTerm *, pRangeEnd, pRangeStart);
+      }
+
+      testcase( pRangeStart && pRangeStart->eOperator & WO_LE );
+      testcase( pRangeStart && pRangeStart->eOperator & WO_GE );
+      testcase( pRangeEnd && pRangeEnd->eOperator & WO_LE );
+      testcase( pRangeEnd && pRangeEnd->eOperator & WO_GE );
+      startEq = !pRangeStart || pRangeStart->eOperator & (WO_LE|WO_GE);
+      endEq =   !pRangeEnd || pRangeEnd->eOperator & (WO_LE|WO_GE);
+      start_constraints = pRangeStart || nEq>0;
+
+      /* Seek the index cursor to the start of the range. */
+      nConstraint = nEq;
+      if( pRangeStart ){
+        int dcc = pParse->disableColCache;
+        if( pRangeEnd ){
+          pParse->disableColCache++;
         }
+        sqlite3ExprCode(pParse, pRangeStart->pExpr->pRight, regBase+nEq);
+        pParse->disableColCache = dcc;
+        sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, nxt);
+        nConstraint++;
+      }else if( isMinQuery ){
+        sqlite3VdbeAddOp2(v, OP_Null, 0, regBase+nEq);
+        nConstraint++;
+        startEq = 0;
+        start_constraints = 1;
+      }
+      codeApplyAffinity(pParse, regBase, nConstraint, pIdx);
+      op = aStartOp[(start_constraints<<2) + (startEq<<1) + bRev];
+      assert( op!=0 );
+      testcase( op==OP_Rewind );
+      testcase( op==OP_Last );
+      testcase( op==OP_MoveGt );
+      testcase( op==OP_MoveGe );
+      testcase( op==OP_MoveLe );
+      testcase( op==OP_MoveLt );
+      sqlite3VdbeAddOp4(v, op, iIdxCur, nxt, regBase, 
+                        SQLITE_INT_TO_PTR(nConstraint), P4_INT32);
+
+      /* Load the value for the inequality constraint at the end of the
+      ** range (if any).
+      */
+      nConstraint = nEq;
+      if( pRangeEnd ){
+        sqlite3ExprCode(pParse, pRangeEnd->pExpr->pRight, regBase+nEq);
+        sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, nxt);
+        codeApplyAffinity(pParse, regBase, nEq+1, pIdx);
+        nConstraint++;
       }
+
+      /* Top of the loop body */
+      pLevel->p2 = sqlite3VdbeCurrentAddr(v);
+
+      /* Check if the index cursor is past the end of the range. */
+      op = aEndOp[(pRangeEnd || nEq) * (1 + bRev)];
+      testcase( op==OP_Noop );
+      testcase( op==OP_IdxGE );
+      testcase( op==OP_IdxLT );
+      sqlite3VdbeAddOp4(v, op, iIdxCur, nxt, regBase,
+                        SQLITE_INT_TO_PTR(nConstraint), P4_INT32);
+      sqlite3VdbeChangeP5(v, endEq!=bRev);
+
+      /* If there are inequality constraints, check that the value
+      ** of the table column that the inequality contrains is not NULL.
+      ** If it is, jump to the next iteration of the loop.
+      */
       r1 = sqlite3GetTempReg(pParse);
-      if( topLimit | btmLimit ){
+      testcase( pLevel->flags & WHERE_BTM_LIMIT );
+      testcase( pLevel->flags & WHERE_TOP_LIMIT );
+      if( pLevel->flags & (WHERE_BTM_LIMIT|WHERE_TOP_LIMIT) ){
         sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, nEq, r1);
         sqlite3VdbeAddOp2(v, OP_IsNull, r1, cont);
       }
+
+      /* Seek the table cursor, if required */
       if( !omitTable ){
         sqlite3VdbeAddOp2(v, OP_IdxRowid, iIdxCur, r1);
         sqlite3VdbeAddOp3(v, OP_MoveGe, iCur, 0, r1);  /* Deferred seek */
       }
       sqlite3ReleaseTempReg(pParse, r1);
 
-      /* Record the instruction used to terminate the loop.
+      /* Record the instruction used to terminate the loop. Disable 
+      ** WHERE clause terms made redundant by the index range scan.
       */
       pLevel->op = bRev ? OP_Prev : OP_Next;
       pLevel->p1 = iIdxCur;
-      pLevel->p2 = start;
-    }else if( pLevel->flags & WHERE_COLUMN_EQ ){
-      /* Case 4:  There is an index and all terms of the WHERE clause that
-      **          refer to the index using the "==" or "IN" operators.
-      */
-      int start;
-      int nEq = pLevel->nEq;
-      int isMinQuery = 0;      /* If this is an optimized SELECT min(x) ... */
-      int regBase;             /* Base register of array holding constraints */
-      int r1;
-
-      /* Generate code to evaluate all constraint terms using == or IN
-      ** and leave the values of those terms on the stack.
-      */
-      regBase = codeAllEqualityTerms(pParse, pLevel, &wc, notReady, 1);
-      nxt = pLevel->nxt;
-
-      if( (obflag==ORDERBY_MIN)
-       && (pLevel->flags&WHERE_ORDERBY) 
-       && (pIdx->nColumn>nEq)
-       && (pOrderBy->a[0].pExpr->iColumn==pIdx->aiColumn[nEq])
-      ){
-        isMinQuery = 1;
-        buildIndexProbe(v, nEq, pIdx, regBase, pLevel->iMem);
-        sqlite3VdbeAddOp2(v, OP_Null, 0, regBase+nEq);
-        r1 = ++pParse->nMem;
-        buildIndexProbe(v, nEq+1, pIdx, regBase, r1);
-      }else{
-        /* Generate a single key that will be used to both start and 
-        ** terminate the search
-        */
-        r1 = pLevel->iMem;
-        buildIndexProbe(v, nEq, pIdx, regBase, r1);
-      }
-
-      /* Generate code (1) to move to the first matching element of the table.
-      ** Then generate code (2) that jumps to "nxt" after the cursor is past
-      ** the last matching element of the table.  The code (1) is executed
-      ** once to initialize the search, the code (2) is executed before each
-      ** iteration of the scan to see if the scan has finished. */
-      if( bRev ){
-        /* Scan in reverse order */
-        int op;
-        if( isMinQuery ){
-          op = OP_MoveLt;
-        }else{
-          op = OP_MoveLe;
-        }
-        sqlite3VdbeAddOp3(v, op, iIdxCur, nxt, r1);
-        start = sqlite3VdbeAddOp3(v, OP_IdxLT, iIdxCur, nxt, pLevel->iMem);
-        pLevel->op = OP_Prev;
-      }else{
-        /* Scan in the forward order */
-        int op;
-        if( isMinQuery ){
-          op = OP_MoveGt;
-        }else{
-          op = OP_MoveGe;
-        }
-        sqlite3VdbeAddOp3(v, op, iIdxCur, nxt, r1);
-        start = sqlite3VdbeAddOp3(v, OP_IdxGE, iIdxCur, nxt, pLevel->iMem);
-        sqlite3VdbeChangeP5(v, 1);
-        pLevel->op = OP_Next;
-      }
-      if( !omitTable ){
-        r1 = sqlite3GetTempReg(pParse);
-        sqlite3VdbeAddOp2(v, OP_IdxRowid, iIdxCur, r1);
-        sqlite3VdbeAddOp3(v, OP_MoveGe, iCur, 0, r1);  /* Deferred seek */
-        sqlite3ReleaseTempReg(pParse, r1);
-      }
-      pLevel->p1 = iIdxCur;
-      pLevel->p2 = start;
+      disableTerm(pLevel, pRangeStart);
+      disableTerm(pLevel, pRangeEnd);
     }else{
-      /* Case 5:  There is no usable index.  We must do a complete
+      /* Case 4:  There is no usable index.  We must do a complete
       **          scan of the entire table.
       */
       assert( omitTable==0 );
@@ -70531,6 +78594,7 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
       pLevel->op = OP_Next;
       pLevel->p1 = iCur;
       pLevel->p2 = 1 + sqlite3VdbeAddOp2(v, OP_Rewind, iCur, brk);
+      pLevel->p5 = SQLITE_STMTSTATUS_FULLSCAN_STEP;
     }
     notReady &= ~getMask(&maskSet, iCur);
 
@@ -70539,6 +78603,8 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
     */
     for(pTerm=wc.a, j=wc.nTerm; j>0; j--, pTerm++){
       Expr *pE;
+      testcase( pTerm->flags & TERM_VIRTUAL );
+      testcase( pTerm->flags & TERM_CODED );
       if( pTerm->flags & (TERM_VIRTUAL|TERM_CODED) ) continue;
       if( (pTerm->prereqAll & notReady)!=0 ) continue;
       pE = pTerm->pExpr;
@@ -70557,7 +78623,11 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
       pLevel->top = sqlite3VdbeCurrentAddr(v);
       sqlite3VdbeAddOp2(v, OP_Integer, 1, pLevel->iLeftJoin);
       VdbeComment((v, "record LEFT JOIN hit"));
+      sqlite3ExprClearColumnCache(pParse, pLevel->iTabCur);
+      sqlite3ExprClearColumnCache(pParse, pLevel->iIdxCur);
       for(pTerm=wc.a, j=0; jflags & TERM_VIRTUAL );
+        testcase( pTerm->flags & TERM_CODED );
         if( pTerm->flags & (TERM_VIRTUAL|TERM_CODED) ) continue;
         if( (pTerm->prereqAll & notReady)!=0 ) continue;
         assert( pTerm->pExpr );
@@ -70592,6 +78662,8 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
       }
       sqlite3_query_plan[nQPlan++] = ' ';
     }
+    testcase( pLevel->flags & WHERE_ROWID_EQ );
+    testcase( pLevel->flags & WHERE_ROWID_RANGE );
     if( pLevel->flags & (WHERE_ROWID_EQ|WHERE_ROWID_RANGE) ){
       memcpy(&sqlite3_query_plan[nQPlan], "* ", 2);
       nQPlan += 2;
@@ -70622,9 +78694,9 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
   return pWInfo;
 
   /* Jump here if malloc fails */
-whereBeginNoMem:
+whereBeginError:
   whereClauseClear(&wc);
-  whereInfoFree(pWInfo);
+  whereInfoFree(db, pWInfo);
   return 0;
 }
 
@@ -70633,18 +78705,22 @@ whereBeginNoMem:
 ** sqlite3WhereBegin() for additional information.
 */
 SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo *pWInfo){
-  Vdbe *v = pWInfo->pParse->pVdbe;
+  Parse *pParse = pWInfo->pParse;
+  Vdbe *v = pParse->pVdbe;
   int i;
   WhereLevel *pLevel;
   SrcList *pTabList = pWInfo->pTabList;
+  sqlite3 *db = pParse->db;
 
   /* Generate loop termination code.
   */
+  sqlite3ExprClearColumnCache(pParse, -1);
   for(i=pTabList->nSrc-1; i>=0; i--){
     pLevel = &pWInfo->a[i];
     sqlite3VdbeResolveLabel(v, pLevel->cont);
     if( pLevel->op!=OP_Noop ){
       sqlite3VdbeAddOp2(v, pLevel->op, pLevel->p1, pLevel->p2);
+      sqlite3VdbeChangeP5(v, pLevel->p5);
     }
     if( pLevel->nIn ){
       struct InLoop *pIn;
@@ -70655,7 +78731,7 @@ SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo *pWInfo){
         sqlite3VdbeAddOp2(v, OP_Next, pIn->iCur, pIn->topAddr);
         sqlite3VdbeJumpHere(v, pIn->topAddr-1);
       }
-      sqlite3_free(pLevel->aInLoop);
+      sqlite3DbFree(db, pLevel->aInLoop);
     }
     sqlite3VdbeResolveLabel(v, pLevel->brk);
     if( pLevel->iLeftJoin ){
@@ -70681,8 +78757,8 @@ SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo *pWInfo){
     struct SrcList_item *pTabItem = &pTabList->a[pLevel->iFrom];
     Table *pTab = pTabItem->pTab;
     assert( pTab!=0 );
-    if( pTab->isEphem || pTab->pSelect ) continue;
-    if( (pLevel->flags & WHERE_IDX_ONLY)==0 ){
+    if( (pTab->tabFlags & TF_Ephemeral)!=0 || pTab->pSelect ) continue;
+    if( !pWInfo->okOnePass && (pLevel->flags & WHERE_IDX_ONLY)==0 ){
       sqlite3VdbeAddOp1(v, OP_Close, pTabItem->iCursor);
     }
     if( pLevel->pIdx!=0 ){
@@ -70734,7 +78810,7 @@ SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo *pWInfo){
 
   /* Final cleanup
   */
-  whereInfoFree(pWInfo);
+  whereInfoFree(db, pWInfo);
   return;
 }
 
@@ -70743,8 +78819,8 @@ SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo *pWInfo){
 /* Driver template for the LEMON parser generator.
 ** The author disclaims copyright to this source code.
 */
-/* First off, code is include which follows the "include" declaration
-** in the input file. */
+/* First off, code is included that follows the "include" declaration
+** in the input grammar file. */
 
 
 /*
@@ -70831,24 +78907,23 @@ struct AttachKey { int type;  Token key; };
 **                       defined, then do no error processing.
 */
 #define YYCODETYPE unsigned char
-#define YYNOCODE 248
+#define YYNOCODE 249
 #define YYACTIONTYPE unsigned short int
 #define YYWILDCARD 59
 #define sqlite3ParserTOKENTYPE Token
 typedef union {
   sqlite3ParserTOKENTYPE yy0;
-  int yy46;
-  struct LikeOp yy72;
-  Expr* yy172;
-  ExprList* yy174;
-  Select* yy219;
-  struct LimitVal yy234;
-  TriggerStep* yy243;
-  struct TrigEvent yy370;
-  SrcList* yy373;
-  struct {int value; int mask;} yy405;
-  Token yy410;
-  IdList* yy432;
+  Select* yy43;
+  TriggerStep* yy75;
+  struct LimitVal yy84;
+  struct LikeOp yy86;
+  struct {int value; int mask;} yy207;
+  ExprList* yy242;
+  int yy316;
+  IdList* yy352;
+  struct TrigEvent yy354;
+  SrcList* yy419;
+  Expr* yy450;
 } YYMINORTYPE;
 #ifndef YYSTACKDEPTH
 #define YYSTACKDEPTH 100
@@ -70857,14 +78932,22 @@ typedef union {
 #define sqlite3ParserARG_PDECL ,Parse *pParse
 #define sqlite3ParserARG_FETCH Parse *pParse = yypParser->pParse
 #define sqlite3ParserARG_STORE yypParser->pParse = pParse
-#define YYNSTATE 588
-#define YYNRULE 312
+#define YYNSTATE 598
+#define YYNRULE 315
 #define YYFALLBACK 1
 #define YY_NO_ACTION      (YYNSTATE+YYNRULE+2)
 #define YY_ACCEPT_ACTION  (YYNSTATE+YYNRULE+1)
 #define YY_ERROR_ACTION   (YYNSTATE+YYNRULE)
 
-/* Next are that tables used to determine what action to take based on the
+/* The yyzerominor constant is used to initialize instances of
+** YYMINORTYPE objects to zero. */
+#if 0
+static YYMINORTYPE yyzerominor;
+#else
+static const YYMINORTYPE yyzerominor;
+#endif
+
+/* Next are the tables used to determine what action to take based on the
 ** current state and lookahead token.  These tables are used to implement
 ** functions that take a state number and lookahead value and return an
 ** action integer.  
@@ -70912,416 +78995,420 @@ typedef union {
 **  yy_default[]       Default action for each state.
 */
 static const YYACTIONTYPE yy_action[] = {
- /*     0 */   292,  901,  124,  587,  409,  172,    2,  418,   61,   61,
- /*    10 */    61,   61,  519,   63,   63,   63,   63,   64,   64,   65,
- /*    20 */    65,   65,   66,  210,  447,  212,  425,  431,   68,   63,
- /*    30 */    63,   63,   63,   64,   64,   65,   65,   65,   66,  210,
- /*    40 */   391,  388,  396,  451,   60,   59,  297,  435,  436,  432,
- /*    50 */   432,   62,   62,   61,   61,   61,   61,  263,   63,   63,
- /*    60 */    63,   63,   64,   64,   65,   65,   65,   66,  210,  292,
- /*    70 */   493,  494,  418,  489,  208,   82,   67,  420,   69,  154,
- /*    80 */    63,   63,   63,   63,   64,   64,   65,   65,   65,   66,
- /*    90 */   210,   67,  462,   69,  154,  425,  431,  573,  264,   58,
- /*   100 */    64,   64,   65,   65,   65,   66,  210,  397,  398,  422,
- /*   110 */   422,  422,  292,   60,   59,  297,  435,  436,  432,  432,
- /*   120 */    62,   62,   61,   61,   61,   61,  317,   63,   63,   63,
- /*   130 */    63,   64,   64,   65,   65,   65,   66,  210,  425,  431,
- /*   140 */    94,   65,   65,   65,   66,  210,  396,  210,  414,   34,
- /*   150 */    56,  298,  442,  443,  410,  488,   60,   59,  297,  435,
- /*   160 */   436,  432,  432,   62,   62,   61,   61,   61,   61,  490,
- /*   170 */    63,   63,   63,   63,   64,   64,   65,   65,   65,   66,
- /*   180 */   210,  292,  257,  524,  295,  571,  113,  408,  522,  451,
- /*   190 */   331,  317,  407,   20,  418,  340,  519,  396,  532,  531,
- /*   200 */   505,  447,  212,  570,  569,  208,  530,  425,  431,  149,
- /*   210 */   150,  397,  398,  414,   41,  211,  151,  533,  372,  489,
- /*   220 */   261,  568,  259,  420,  292,   60,   59,  297,  435,  436,
- /*   230 */   432,  432,   62,   62,   61,   61,   61,   61,  317,   63,
- /*   240 */    63,   63,   63,   64,   64,   65,   65,   65,   66,  210,
- /*   250 */   425,  431,  447,  333,  215,  422,  422,  422,  363,  418,
- /*   260 */   414,   41,  397,  398,  366,  567,  211,  292,   60,   59,
- /*   270 */   297,  435,  436,  432,  432,   62,   62,   61,   61,   61,
- /*   280 */    61,  396,   63,   63,   63,   63,   64,   64,   65,   65,
- /*   290 */    65,   66,  210,  425,  431,  491,  300,  524,  474,   66,
- /*   300 */   210,  214,  474,  229,  411,  286,  534,   20,  449,  523,
- /*   310 */   168,   60,   59,  297,  435,  436,  432,  432,   62,   62,
- /*   320 */    61,   61,   61,   61,  474,   63,   63,   63,   63,   64,
- /*   330 */    64,   65,   65,   65,   66,  210,  209,  480,  317,   77,
- /*   340 */   292,  239,  300,   55,  484,  230,  397,  398,  181,  547,
- /*   350 */   494,  345,  348,  349,   67,  152,   69,  154,  339,  524,
- /*   360 */   414,   35,  350,  241,  221,  370,  425,  431,  578,   20,
- /*   370 */   164,  118,  243,  343,  248,  344,  176,  322,  442,  443,
- /*   380 */   414,    3,   80,  252,   60,   59,  297,  435,  436,  432,
- /*   390 */   432,   62,   62,   61,   61,   61,   61,  174,   63,   63,
- /*   400 */    63,   63,   64,   64,   65,   65,   65,   66,  210,  292,
- /*   410 */   221,  550,  236,  487,  510,  353,  317,  118,  243,  343,
- /*   420 */   248,  344,  176,  181,  317,  525,  345,  348,  349,  252,
- /*   430 */   223,  415,  155,  464,  511,  425,  431,  350,  414,   34,
- /*   440 */   465,  211,  177,  175,  160,  237,  414,   34,  338,  549,
- /*   450 */   449,  323,  168,   60,   59,  297,  435,  436,  432,  432,
- /*   460 */    62,   62,   61,   61,   61,   61,  415,   63,   63,   63,
- /*   470 */    63,   64,   64,   65,   65,   65,   66,  210,  292,  542,
- /*   480 */   335,  517,  504,  541,  456,  571,  302,   19,  331,  144,
- /*   490 */   317,  390,  317,  330,    2,  362,  457,  294,  483,  373,
- /*   500 */   269,  268,  252,  570,  425,  431,  588,  391,  388,  458,
- /*   510 */   208,  495,  414,   49,  414,   49,  303,  585,  892,  159,
- /*   520 */   892,  496,   60,   59,  297,  435,  436,  432,  432,   62,
- /*   530 */    62,   61,   61,   61,   61,  201,   63,   63,   63,   63,
- /*   540 */    64,   64,   65,   65,   65,   66,  210,  292,  317,  181,
- /*   550 */   439,  255,  345,  348,  349,  370,  153,  582,  308,  251,
- /*   560 */   309,  452,   76,  350,   78,  382,  211,  426,  427,  415,
- /*   570 */   414,   27,  319,  425,  431,  440,    1,   22,  585,  891,
- /*   580 */   396,  891,  544,  478,  320,  263,  438,  438,  429,  430,
- /*   590 */   415,   60,   59,  297,  435,  436,  432,  432,   62,   62,
- /*   600 */    61,   61,   61,   61,  328,   63,   63,   63,   63,   64,
- /*   610 */    64,   65,   65,   65,   66,  210,  292,  428,  582,  374,
- /*   620 */   224,   93,  517,    9,  336,  396,  557,  396,  456,   67,
- /*   630 */   396,   69,  154,  399,  400,  401,  320,  238,  438,  438,
- /*   640 */   457,  318,  425,  431,  299,  397,  398,  320,  433,  438,
- /*   650 */   438,  581,  291,  458,  225,  327,    5,  222,  546,  292,
- /*   660 */    60,   59,  297,  435,  436,  432,  432,   62,   62,   61,
- /*   670 */    61,   61,   61,  395,   63,   63,   63,   63,   64,   64,
- /*   680 */    65,   65,   65,   66,  210,  425,  431,  482,  313,  392,
- /*   690 */   397,  398,  397,  398,  207,  397,  398,  824,  273,  517,
- /*   700 */   251,  200,  292,   60,   59,  297,  435,  436,  432,  432,
- /*   710 */    62,   62,   61,   61,   61,   61,  470,   63,   63,   63,
- /*   720 */    63,   64,   64,   65,   65,   65,   66,  210,  425,  431,
- /*   730 */   171,  160,  263,  263,  304,  415,  276,  119,  274,  263,
- /*   740 */   517,  517,  263,  517,  192,  292,   60,   70,  297,  435,
- /*   750 */   436,  432,  432,   62,   62,   61,   61,   61,   61,  379,
- /*   760 */    63,   63,   63,   63,   64,   64,   65,   65,   65,   66,
- /*   770 */   210,  425,  431,  384,  559,  305,  306,  251,  415,  320,
- /*   780 */   560,  438,  438,  561,  540,  360,  540,  387,  292,  196,
- /*   790 */    59,  297,  435,  436,  432,  432,   62,   62,   61,   61,
- /*   800 */    61,   61,  371,   63,   63,   63,   63,   64,   64,   65,
- /*   810 */    65,   65,   66,  210,  425,  431,  396,  275,  251,  251,
- /*   820 */   172,  250,  418,  415,  386,  367,  178,  179,  180,  469,
- /*   830 */   311,  123,  156,  128,  297,  435,  436,  432,  432,   62,
- /*   840 */    62,   61,   61,   61,   61,  317,   63,   63,   63,   63,
- /*   850 */    64,   64,   65,   65,   65,   66,  210,   72,  324,  177,
- /*   860 */     4,  317,  263,  317,  296,  263,  415,  414,   28,  317,
- /*   870 */   263,  317,  321,   72,  324,  317,    4,  421,  445,  445,
- /*   880 */   296,  397,  398,  414,   23,  414,   32,  418,  321,  326,
- /*   890 */   329,  414,   53,  414,   52,  317,  158,  414,   98,  451,
- /*   900 */   317,  194,  317,  277,  317,  326,  378,  471,  502,  317,
- /*   910 */   478,  279,  478,  165,  294,  451,  317,  414,   96,   75,
- /*   920 */    74,  469,  414,  101,  414,  102,  414,  112,   73,  315,
- /*   930 */   316,  414,  114,  420,  448,   75,   74,  481,  414,   16,
- /*   940 */   381,  317,  183,  467,   73,  315,  316,   72,  324,  420,
- /*   950 */     4,  208,  317,  186,  296,  317,  499,  500,  476,  208,
- /*   960 */   173,  341,  321,  414,   99,  422,  422,  422,  423,  424,
- /*   970 */    11,  361,  380,  307,  414,   33,  415,  414,   97,  326,
- /*   980 */   460,  422,  422,  422,  423,  424,   11,  415,  413,  451,
- /*   990 */   413,  162,  412,  317,  412,  468,  226,  227,  228,  104,
- /*  1000 */    84,  473,  317,  509,  508,  317,  622,  477,  317,   75,
- /*  1010 */    74,  249,  205,   21,  281,  414,   24,  418,   73,  315,
- /*  1020 */   316,  282,  317,  420,  414,   54,  507,  414,  115,  317,
- /*  1030 */   414,  116,  506,  203,  147,  549,  244,  512,  526,  202,
- /*  1040 */   317,  513,  204,  317,  414,  117,  317,  245,  317,   18,
- /*  1050 */   317,  414,   25,  317,  256,  422,  422,  422,  423,  424,
- /*  1060 */    11,  258,  414,   36,  260,  414,   37,  317,  414,   26,
- /*  1070 */   414,   38,  414,   39,  262,  414,   40,  317,  514,  317,
- /*  1080 */   128,  317,  418,  317,  189,  377,  278,  268,  267,  414,
- /*  1090 */    42,  293,  317,  254,  317,  128,  208,  365,    8,  414,
- /*  1100 */    43,  414,   44,  414,   29,  414,   30,  352,  368,  128,
- /*  1110 */   317,  545,  317,  128,  414,   45,  414,   46,  317,  583,
- /*  1120 */   383,  553,  317,  173,  554,  317,   91,  317,  564,  369,
- /*  1130 */    91,  357,  414,   47,  414,   48,  580,  270,  290,  271,
- /*  1140 */   414,   31,  272,  556,  414,   10,  566,  414,   50,  414,
- /*  1150 */    51,  280,  283,  284,  577,  146,  463,  405,  584,  231,
- /*  1160 */   325,  419,  444,  466,  446,  246,  505,  552,  563,  515,
- /*  1170 */   516,  520,  163,  518,  394,  347,    7,  402,  403,  404,
- /*  1180 */   314,   84,  232,  334,  332,   83,   79,  416,  170,   57,
- /*  1190 */   213,  461,  125,   85,  337,  342,  492,  301,  233,  498,
- /*  1200 */   497,  105,  502,  219,  354,  247,  521,  234,  501,  235,
- /*  1210 */   287,  417,  503,  218,  527,  528,  529,  358,  240,  535,
- /*  1220 */   475,  242,  288,  479,  356,  184,  185,  121,  187,  132,
- /*  1230 */   188,  548,  537,   88,  190,  193,  364,  142,  375,  376,
- /*  1240 */   555,  133,  220,  562,  134,  310,  135,  138,  136,  574,
- /*  1250 */   575,  141,  576,  265,  579,  100,  538,  217,  393,   92,
- /*  1260 */   103,   95,  406,  623,  624,  166,  434,  167,  437,   71,
- /*  1270 */   453,  441,  450,   17,  143,  157,  169,    6,  111,   13,
- /*  1280 */   454,  455,  459,  472,  126,   81,   12,  127,  161,  485,
- /*  1290 */   486,  216,   86,  122,  106,  182,  253,  346,  312,  107,
- /*  1300 */   120,   87,  351,  108,  245,  355,  145,  536,  359,  129,
- /*  1310 */   173,  266,  191,  109,  289,  551,  130,  539,  195,  543,
- /*  1320 */   131,   14,  197,  199,  198,  558,  137,  139,  140,  110,
- /*  1330 */    15,  285,  572,  206,  389,  565,  385,  148,  586,  902,
- /*  1340 */   902,  902,  902,  902,  902,   89,   90,
+ /*     0 */   296,  914,  120,  597,    2,  172,  425,  425,   62,   62,
+ /*    10 */    62,   62,  210,   64,   64,   64,   64,   65,   65,   66,
+ /*    20 */    66,   66,   67,  212,  398,  395,  432,  438,   69,   64,
+ /*    30 */    64,   64,   64,   65,   65,   66,   66,   66,   67,  212,
+ /*    40 */   458,  456,  327,  168,   61,   60,  301,  442,  443,  439,
+ /*    50 */   439,   63,   63,   62,   62,   62,   62,  256,   64,   64,
+ /*    60 */    64,   64,   65,   65,   66,   66,   66,   67,  212,  296,
+ /*    70 */   498,  425,  425,  212,  427,   83,   68,  469,   70,  154,
+ /*    80 */    64,   64,   64,   64,   65,   65,   66,   66,   66,   67,
+ /*    90 */   212,   68,  307,   70,  154,  432,  438,  454,  214,   59,
+ /*   100 */    65,   65,   66,   66,   66,   67,  212,  429,  429,  429,
+ /*   110 */   497,  583,  296,   61,   60,  301,  442,  443,  439,  439,
+ /*   120 */    63,   63,   62,   62,   62,   62,  321,   64,   64,   64,
+ /*   130 */    64,   65,   65,   66,   66,   66,   67,  212,  432,  438,
+ /*   140 */    95,   66,   66,   66,   67,  212,  403,  256,  421,   35,
+ /*   150 */    57,   67,  212,  175,  417,  499,   61,   60,  301,  442,
+ /*   160 */   443,  439,  439,   63,   63,   62,   62,   62,   62,   19,
+ /*   170 */    64,   64,   64,   64,   65,   65,   66,   66,   66,   67,
+ /*   180 */   212,  296,  225,  532,  299,  581,  109,  422,  242,  458,
+ /*   190 */   416,  335,  414,   21,  502,  503,  346,  403,  527,  176,
+ /*   200 */   160,  454,  214,  580,  579,  344,  500,  432,  438,  149,
+ /*   210 */   150,  404,  405,  539,  514,  418,  151,  541,    8,  498,
+ /*   220 */   538,  577,  578,  427,  296,   61,   60,  301,  442,  443,
+ /*   230 */   439,  439,   63,   63,   62,   62,   62,   62,  196,   64,
+ /*   240 */    64,   64,   64,   65,   65,   66,   66,   66,   67,  212,
+ /*   250 */   432,  438,  454,  598,  398,  395,  429,  429,  429,  369,
+ /*   260 */   558,  481,  404,  405,  372,  576,  213,  296,   61,   60,
+ /*   270 */   301,  442,  443,  439,  439,   63,   63,   62,   62,   62,
+ /*   280 */    62,  321,   64,   64,   64,   64,   65,   65,   66,   66,
+ /*   290 */    66,   67,  212,  432,  438,  555,  503,  304,  557,  532,
+ /*   300 */   218,  557,  552,  421,   36,  234,  397,    2,  542,   21,
+ /*   310 */   540,   61,   60,  301,  442,  443,  439,  439,   63,   63,
+ /*   320 */    62,   62,   62,   62,  388,   64,   64,   64,   64,   65,
+ /*   330 */    65,   66,   66,   66,   67,  212,  415,  530,   85,  381,
+ /*   340 */    78,  323,  296,  210,  304,  527,  493,  492,  379,  274,
+ /*   350 */   273,  379,  274,  273,  347,  463,  241,  387,  268,  210,
+ /*   360 */   533,  581,  210,  403,   20,  224,  144,  464,  432,  438,
+ /*   370 */   485,  164,  114,  248,  349,  253,  350,  177,  554,  580,
+ /*   380 */   465,  420,  331,   81,  257,  419,   61,   60,  301,  442,
+ /*   390 */   443,  439,  439,   63,   63,   62,   62,   62,   62,  391,
+ /*   400 */    64,   64,   64,   64,   65,   65,   66,   66,   66,   67,
+ /*   410 */   212,  296,  224,  203,  249,  496,  403,  440,  837,  114,
+ /*   420 */   248,  349,  253,  350,  177,  250,  321,  152,  404,  405,
+ /*   430 */   321,  257,  303,  324,  155,  445,  445,  432,  438,  317,
+ /*   440 */   400,  389,  213,   68,  209,   70,  154,  422,  421,   35,
+ /*   450 */   393,  202,  421,   42,  481,   61,   60,  301,  442,  443,
+ /*   460 */   439,  439,   63,   63,   62,   62,   62,   62,  422,   64,
+ /*   470 */    64,   64,   64,   65,   65,   66,   66,   66,   67,  212,
+ /*   480 */   296,  404,  405,  183,  513,  422,  351,  354,  355,  403,
+ /*   490 */    77,  335,   79,  489,  216,  183,  334,  356,  351,  354,
+ /*   500 */   355,  433,  434,  406,  407,  408,  432,  438,  235,  356,
+ /*   510 */   386,   68,  291,   70,  154,  456,  531,  168,  198,  302,
+ /*   520 */   449,  450,  436,  437,   61,   60,  301,  442,  443,  439,
+ /*   530 */   439,   63,   63,   62,   62,   62,   62,  394,   64,   64,
+ /*   540 */    64,   64,   65,   65,   66,   66,   66,   67,  212,  296,
+ /*   550 */   321,  435,  422,  260,  404,  405,  321,  183,  153,  321,
+ /*   560 */   351,  354,  355,  446,  332,  321,  595,  905,  321,  905,
+ /*   570 */     1,  356,  421,   28,  403,  432,  438,  376,  421,   42,
+ /*   580 */   477,  421,   35,  213,  548,  366,  548,  421,   50,  159,
+ /*   590 */   421,   50,  422,   61,   60,  301,  442,  443,  439,  439,
+ /*   600 */    63,   63,   62,   62,   62,   62,  592,   64,   64,   64,
+ /*   610 */    64,   65,   65,   66,   66,   66,   67,  212,  296,  337,
+ /*   620 */   217,  463,  256,   94,  339,  326,  449,  450,  172,  340,
+ /*   630 */   425,  345,  532,  464,  312,  595,  904,  313,  904,  404,
+ /*   640 */   405,  588,   21,  226,  432,  438,  465,  243,  504,  324,
+ /*   650 */   322,  445,  445,  421,    3,  459,  230,  308,  505,  194,
+ /*   660 */   278,  296,   61,   60,  301,  442,  443,  439,  439,   63,
+ /*   670 */    63,   62,   62,   62,   62,  592,   64,   64,   64,   64,
+ /*   680 */    65,   65,   66,   66,   66,   67,  212,  432,  438,  213,
+ /*   690 */   179,  180,  181,  422,  324,  425,  445,  445,  281,  262,
+ /*   700 */   279,  402,  194,  481,  296,   61,   60,  301,  442,  443,
+ /*   710 */   439,  439,   63,   63,   62,   62,   62,   62,  377,   64,
+ /*   720 */    64,   64,   64,   65,   65,   66,   66,   66,   67,  212,
+ /*   730 */   432,  438,  591,  295,  115,  268,  422,  266,  211,  264,
+ /*   740 */   373,  324,  246,  445,  445,   56,  256,  296,   61,   71,
+ /*   750 */   301,  442,  443,  439,  439,   63,   63,   62,   62,   62,
+ /*   760 */    62,  377,   64,   64,   64,   64,   65,   65,   66,   66,
+ /*   770 */    66,   67,  212,  432,  438,  550,  269,  474,   18,  549,
+ /*   780 */   280,  309,  343,  380,  171,  160,  256,  268,    5,  268,
+ /*   790 */   296,  368,   60,  301,  442,  443,  439,  439,   63,   63,
+ /*   800 */    62,   62,   62,   62,  321,   64,   64,   64,   64,   65,
+ /*   810 */    65,   66,   66,   66,   67,  212,  432,  438,  403,   10,
+ /*   820 */   403,  310,  268,  403,  268,  485,  421,   29,  566,   22,
+ /*   830 */   568,  420,  428,  425,  376,  419,  301,  442,  443,  439,
+ /*   840 */   439,   63,   63,   62,   62,   62,   62,  321,   64,   64,
+ /*   850 */    64,   64,   65,   65,   66,   66,   66,   67,  212,   73,
+ /*   860 */   328,  485,    4,  569,  268,  570,  300,  268,  147,  421,
+ /*   870 */    24,  321,  359,  321,  325,   73,  328,  491,    4,  455,
+ /*   880 */   321,  342,  300,  404,  405,  404,  405,  367,  404,  405,
+ /*   890 */   325,  330,  321,  421,   33,  421,   54,  321,  425,  178,
+ /*   900 */   229,  458,  421,   53,  321,  227,  321,  330,  228,  478,
+ /*   910 */   165,  321,  315,  119,  421,   99,  333,  458,  321,  421,
+ /*   920 */    97,   76,   75,  311,  268,  519,  421,  102,  421,  103,
+ /*   930 */    74,  319,  320,  421,  108,  427,  467,   76,   75,  490,
+ /*   940 */   421,  110,  452,  452,  321,  520,   74,  319,  320,   73,
+ /*   950 */   328,  427,    4,  210,  298,  321,  300,  321,  156,  257,
+ /*   960 */   321,  210,  185,  182,  325,  284,  421,   17,  429,  429,
+ /*   970 */   429,  430,  431,   12,  593,  378,  188,  421,  100,  421,
+ /*   980 */    34,  330,  421,   98,  429,  429,  429,  430,  431,   12,
+ /*   990 */   475,  458,  422,  162,  480,  321,  422,  306,  231,  232,
+ /*  1000 */   233,  105,  484,  632,  476,  321,  486,  447,  321,   23,
+ /*  1010 */   422,   76,   75,  594,  207,  178,  286,  421,   25,  254,
+ /*  1020 */    74,  319,  320,  287,  321,  427,  321,  421,   55,  321,
+ /*  1030 */   421,  111,  321,  471,  321,  205,  515,  557,  511,  363,
+ /*  1040 */   472,  204,  321,  516,  206,  321,  421,  112,  421,  113,
+ /*  1050 */   321,  421,   26,  321,  421,   37,  421,   38,  429,  429,
+ /*  1060 */   429,  430,  431,   12,  421,   27,  521,  421,   39,  321,
+ /*  1070 */   298,  158,  421,   40,  255,  421,   41,  321,  483,  321,
+ /*  1080 */   173,  523,  321,  182,  321,  522,  321,  384,  283,  273,
+ /*  1090 */   321,  421,   43,  297,  534,  321,  476,  321,  210,  421,
+ /*  1100 */    44,  421,   45,  321,  421,   30,  421,   31,  421,   46,
+ /*  1110 */   508,  509,  421,   47,  259,  321,  182,  421,   48,  421,
+ /*  1120 */    49,  321,  358,  390,  182,  421,   32,  321,  261,  518,
+ /*  1130 */   517,  553,  561,  182,  173,  412,  191,  421,   11,  562,
+ /*  1140 */   573,   92,   92,  421,   51,  590,  263,  294,  265,  421,
+ /*  1150 */    52,  267,  272,  371,  146,  374,  375,  275,  276,  277,
+ /*  1160 */   565,  575,  285,  288,  289,  587,  470,  451,  236,  453,
+ /*  1170 */   329,  244,  473,  514,  251,  524,  560,  163,  401,  572,
+ /*  1180 */   426,  525,  282,  528,  409,    7,  410,  411,  385,  318,
+ /*  1190 */    85,  237,  338,  526,   84,  336,  353,   58,   80,  215,
+ /*  1200 */   170,  468,  121,   86,  341,  348,  305,  501,  506,  124,
+ /*  1210 */   511,  222,  360,  423,  252,  186,  512,  510,  221,  223,
+ /*  1220 */   238,  507,  239,  535,  240,  292,  424,  529,  536,  537,
+ /*  1230 */   293,  543,  187,  189,  245,  362,  482,  488,  247,  190,
+ /*  1240 */   364,   89,  545,  192,  117,  370,  132,  556,  563,  195,
+ /*  1250 */   382,  383,  314,  133,  134,  571,  138,  135,  136,  584,
+ /*  1260 */   589,  585,  142,  399,  101,  413,  220,  586,  270,  104,
+ /*  1270 */   141,  633,  634,  166,  167,  441,  444,   72,  460,  448,
+ /*  1280 */   457,  546,  143,  157,    6,  461,   14,  479,  169,  462,
+ /*  1290 */    93,  466,   82,  122,   13,  174,  487,   96,  123,  161,
+ /*  1300 */   494,  495,   87,  125,  126,  116,  258,   88,  127,  184,
+ /*  1310 */   250,  361,  219,  107,  544,  145,  128,  193,  365,  118,
+ /*  1320 */   352,  357,  173,  271,  130,    9,  316,  559,  197,   90,
+ /*  1330 */   547,  131,  129,   15,  199,  551,  564,  200,  567,  201,
+ /*  1340 */   139,  137,  582,   91,   16,  106,  140,  208,  574,  392,
+ /*  1350 */   396,  290,  148,  596,
 };
 static const YYCODETYPE yy_lookahead[] = {
- /*     0 */    16,  139,  140,  141,  168,   21,  144,   23,   69,   70,
- /*    10 */    71,   72,  176,   74,   75,   76,   77,   78,   79,   80,
- /*    20 */    81,   82,   83,   84,   78,   79,   42,   43,   73,   74,
+ /*     0 */    16,  140,  141,  142,  143,   21,   23,   23,   69,   70,
+ /*    10 */    71,   72,  110,   74,   75,   76,   77,   78,   79,   80,
+ /*    20 */    81,   82,   83,   84,    1,    2,   42,   43,   73,   74,
  /*    30 */    75,   76,   77,   78,   79,   80,   81,   82,   83,   84,
- /*    40 */     1,    2,   23,   58,   60,   61,   62,   63,   64,   65,
- /*    50 */    66,   67,   68,   69,   70,   71,   72,  147,   74,   75,
+ /*    40 */    58,  162,  163,  164,   60,   61,   62,   63,   64,   65,
+ /*    50 */    66,   67,   68,   69,   70,   71,   72,  148,   74,   75,
  /*    60 */    76,   77,   78,   79,   80,   81,   82,   83,   84,   16,
- /*    70 */   185,  186,   88,   88,  110,   22,  217,   92,  219,  220,
+ /*    70 */    88,   88,   88,   84,   92,   22,  219,  220,  221,  222,
  /*    80 */    74,   75,   76,   77,   78,   79,   80,   81,   82,   83,
- /*    90 */    84,  217,  218,  219,  220,   42,   43,  238,  188,   46,
- /*   100 */    78,   79,   80,   81,   82,   83,   84,   88,   89,  124,
- /*   110 */   125,  126,   16,   60,   61,   62,   63,   64,   65,   66,
- /*   120 */    67,   68,   69,   70,   71,   72,  147,   74,   75,   76,
+ /*    90 */    84,  219,  183,  221,  222,   42,   43,   78,   79,   46,
+ /*   100 */    78,   79,   80,   81,   82,   83,   84,  125,  126,  127,
+ /*   110 */   170,  239,   16,   60,   61,   62,   63,   64,   65,   66,
+ /*   120 */    67,   68,   69,   70,   71,   72,  148,   74,   75,   76,
  /*   130 */    77,   78,   79,   80,   81,   82,   83,   84,   42,   43,
- /*   140 */    44,   80,   81,   82,   83,   84,   23,   84,  169,  170,
- /*   150 */    19,  164,  165,  166,   23,  169,   60,   61,   62,   63,
- /*   160 */    64,   65,   66,   67,   68,   69,   70,   71,   72,  169,
+ /*   140 */    44,   80,   81,   82,   83,   84,   23,  148,  170,  171,
+ /*   150 */    19,   83,   84,  156,   23,  170,   60,   61,   62,   63,
+ /*   160 */    64,   65,   66,   67,   68,   69,   70,   71,   72,   19,
  /*   170 */    74,   75,   76,   77,   78,   79,   80,   81,   82,   83,
- /*   180 */    84,   16,   14,  147,  150,  147,   21,  167,  168,   58,
- /*   190 */   211,  147,  156,  157,   23,  216,  176,   23,  181,  176,
- /*   200 */   177,   78,   79,  165,  166,  110,  183,   42,   43,   78,
- /*   210 */    79,   88,   89,  169,  170,  228,  180,  181,  123,   88,
- /*   220 */    52,   98,   54,   92,   16,   60,   61,   62,   63,   64,
- /*   230 */    65,   66,   67,   68,   69,   70,   71,   72,  147,   74,
+ /*   180 */    84,   16,  183,  148,  151,  148,   21,  190,  148,   58,
+ /*   190 */   169,  213,  157,  158,  186,  187,  218,   23,  177,  202,
+ /*   200 */   203,   78,   79,  166,  167,  208,  161,   42,   43,   78,
+ /*   210 */    79,   88,   89,  177,  178,  170,  181,  182,   68,   88,
+ /*   220 */   184,   98,   99,   92,   16,   60,   61,   62,   63,   64,
+ /*   230 */    65,   66,   67,   68,   69,   70,   71,   72,   22,   74,
  /*   240 */    75,   76,   77,   78,   79,   80,   81,   82,   83,   84,
- /*   250 */    42,   43,   78,  209,  210,  124,  125,  126,  224,   88,
- /*   260 */   169,  170,   88,   89,  230,  227,  228,   16,   60,   61,
+ /*   250 */    42,   43,   78,    0,    1,    2,  125,  126,  127,  226,
+ /*   260 */    11,  162,   88,   89,  231,  228,  229,   16,   60,   61,
  /*   270 */    62,   63,   64,   65,   66,   67,   68,   69,   70,   71,
- /*   280 */    72,   23,   74,   75,   76,   77,   78,   79,   80,   81,
- /*   290 */    82,   83,   84,   42,   43,  160,   16,  147,  161,   83,
- /*   300 */    84,  210,  161,  153,  169,  158,  156,  157,  161,  162,
- /*   310 */   163,   60,   61,   62,   63,   64,   65,   66,   67,   68,
- /*   320 */    69,   70,   71,   72,  161,   74,   75,   76,   77,   78,
- /*   330 */    79,   80,   81,   82,   83,   84,  192,  200,  147,  131,
- /*   340 */    16,  200,   16,  199,   20,  190,   88,   89,   90,  185,
- /*   350 */   186,   93,   94,   95,  217,   22,  219,  220,  147,  147,
- /*   360 */   169,  170,  104,  200,   84,  147,   42,   43,  156,  157,
- /*   370 */    90,   91,   92,   93,   94,   95,   96,  164,  165,  166,
- /*   380 */   169,  170,  131,  103,   60,   61,   62,   63,   64,   65,
- /*   390 */    66,   67,   68,   69,   70,   71,   72,  155,   74,   75,
- /*   400 */    76,   77,   78,   79,   80,   81,   82,   83,   84,   16,
- /*   410 */    84,   11,  221,   20,   30,   16,  147,   91,   92,   93,
- /*   420 */    94,   95,   96,   90,  147,  181,   93,   94,   95,  103,
- /*   430 */   212,  189,  155,   27,   50,   42,   43,  104,  169,  170,
- /*   440 */    34,  228,   43,  201,  202,  147,  169,  170,  206,   49,
- /*   450 */   161,  162,  163,   60,   61,   62,   63,   64,   65,   66,
- /*   460 */    67,   68,   69,   70,   71,   72,  189,   74,   75,   76,
- /*   470 */    77,   78,   79,   80,   81,   82,   83,   84,   16,   25,
- /*   480 */   211,  147,   20,   29,   12,  147,  102,   19,  211,   21,
- /*   490 */   147,  141,  147,  216,  144,   41,   24,   98,   20,   99,
- /*   500 */   100,  101,  103,  165,   42,   43,    0,    1,    2,   37,
- /*   510 */   110,   39,  169,  170,  169,  170,  182,   19,   20,  147,
- /*   520 */    22,   49,   60,   61,   62,   63,   64,   65,   66,   67,
- /*   530 */    68,   69,   70,   71,   72,  155,   74,   75,   76,   77,
- /*   540 */    78,   79,   80,   81,   82,   83,   84,   16,  147,   90,
- /*   550 */    20,   20,   93,   94,   95,  147,  155,   59,  215,  225,
- /*   560 */   215,   20,  130,  104,  132,  227,  228,   42,   43,  189,
- /*   570 */   169,  170,   16,   42,   43,   20,   19,   22,   19,   20,
- /*   580 */    23,   22,   18,  147,  106,  147,  108,  109,   63,   64,
- /*   590 */   189,   60,   61,   62,   63,   64,   65,   66,   67,   68,
- /*   600 */    69,   70,   71,   72,  186,   74,   75,   76,   77,   78,
- /*   610 */    79,   80,   81,   82,   83,   84,   16,   92,   59,   55,
- /*   620 */   212,   21,  147,   19,  147,   23,  188,   23,   12,  217,
- /*   630 */    23,  219,  220,    7,    8,    9,  106,  147,  108,  109,
- /*   640 */    24,  147,   42,   43,  208,   88,   89,  106,   92,  108,
- /*   650 */   109,  244,  245,   37,  145,   39,  191,  182,   94,   16,
- /*   660 */    60,   61,   62,   63,   64,   65,   66,   67,   68,   69,
- /*   670 */    70,   71,   72,  147,   74,   75,   76,   77,   78,   79,
- /*   680 */    80,   81,   82,   83,   84,   42,   43,   80,  142,  143,
- /*   690 */    88,   89,   88,   89,  148,   88,   89,  133,   14,  147,
- /*   700 */   225,  155,   16,   60,   61,   62,   63,   64,   65,   66,
- /*   710 */    67,   68,   69,   70,   71,   72,  114,   74,   75,   76,
- /*   720 */    77,   78,   79,   80,   81,   82,   83,   84,   42,   43,
- /*   730 */   201,  202,  147,  147,  182,  189,   52,  147,   54,  147,
- /*   740 */   147,  147,  147,  147,  155,   16,   60,   61,   62,   63,
- /*   750 */    64,   65,   66,   67,   68,   69,   70,   71,   72,  213,
- /*   760 */    74,   75,   76,   77,   78,   79,   80,   81,   82,   83,
- /*   770 */    84,   42,   43,  188,  188,  182,  182,  225,  189,  106,
- /*   780 */   188,  108,  109,  188,   99,  100,  101,  241,   16,  155,
- /*   790 */    61,   62,   63,   64,   65,   66,   67,   68,   69,   70,
- /*   800 */    71,   72,  213,   74,   75,   76,   77,   78,   79,   80,
- /*   810 */    81,   82,   83,   84,   42,   43,   23,  133,  225,  225,
- /*   820 */    21,  225,   23,  189,  239,  236,   99,  100,  101,   22,
- /*   830 */   242,  243,  155,   22,   62,   63,   64,   65,   66,   67,
- /*   840 */    68,   69,   70,   71,   72,  147,   74,   75,   76,   77,
- /*   850 */    78,   79,   80,   81,   82,   83,   84,   16,   17,   43,
- /*   860 */    19,  147,  147,  147,   23,  147,  189,  169,  170,  147,
- /*   870 */   147,  147,   31,   16,   17,  147,   19,  147,  124,  125,
- /*   880 */    23,   88,   89,  169,  170,  169,  170,   88,   31,   48,
- /*   890 */   147,  169,  170,  169,  170,  147,   89,  169,  170,   58,
- /*   900 */   147,   22,  147,  188,  147,   48,  188,  114,   97,  147,
- /*   910 */   147,  188,  147,   19,   98,   58,  147,  169,  170,   78,
- /*   920 */    79,  114,  169,  170,  169,  170,  169,  170,   87,   88,
- /*   930 */    89,  169,  170,   92,  161,   78,   79,   80,  169,  170,
- /*   940 */    91,  147,  155,   22,   87,   88,   89,   16,   17,   92,
- /*   950 */    19,  110,  147,  155,   23,  147,    7,    8,   20,  110,
- /*   960 */    22,   80,   31,  169,  170,  124,  125,  126,  127,  128,
- /*   970 */   129,  208,  123,  208,  169,  170,  189,  169,  170,   48,
- /*   980 */   147,  124,  125,  126,  127,  128,  129,  189,  107,   58,
- /*   990 */   107,    5,  111,  147,  111,  203,   10,   11,   12,   13,
- /*  1000 */   121,  147,  147,   91,   92,  147,  112,  147,  147,   78,
- /*  1010 */    79,  147,   26,   19,   28,  169,  170,   23,   87,   88,
- /*  1020 */    89,   35,  147,   92,  169,  170,  178,  169,  170,  147,
- /*  1030 */   169,  170,  147,   47,  113,   49,   92,  178,  147,   53,
- /*  1040 */   147,  178,   56,  147,  169,  170,  147,  103,  147,   19,
- /*  1050 */   147,  169,  170,  147,  147,  124,  125,  126,  127,  128,
- /*  1060 */   129,  147,  169,  170,  147,  169,  170,  147,  169,  170,
- /*  1070 */   169,  170,  169,  170,  147,  169,  170,  147,   20,  147,
- /*  1080 */    22,  147,   88,  147,  232,   99,  100,  101,  147,  169,
- /*  1090 */   170,  105,  147,   20,  147,   22,  110,  147,   68,  169,
- /*  1100 */   170,  169,  170,  169,  170,  169,  170,   20,  147,   22,
- /*  1110 */   147,   20,  147,   22,  169,  170,  169,  170,  147,   20,
- /*  1120 */   134,   20,  147,   22,   20,  147,   22,  147,   20,  147,
- /*  1130 */    22,  233,  169,  170,  169,  170,   20,  147,   22,  147,
- /*  1140 */   169,  170,  147,  147,  169,  170,  147,  169,  170,  169,
- /*  1150 */   170,  147,  147,  147,  147,  191,  172,  149,   59,  193,
- /*  1160 */   223,  161,  229,  172,  229,  172,  177,  194,  194,  172,
- /*  1170 */   161,  161,    6,  172,  146,  173,   22,  146,  146,  146,
- /*  1180 */   154,  121,  194,  118,  116,  119,  130,  189,  112,  120,
- /*  1190 */   222,  152,  152,   98,  115,   98,  171,   40,  195,  179,
- /*  1200 */   171,   19,   97,   84,   15,  171,  179,  196,  173,  197,
- /*  1210 */   174,  198,  171,  226,  171,  171,  171,   38,  204,  152,
- /*  1220 */   205,  204,  174,  205,  152,  151,  151,   60,  151,   19,
- /*  1230 */   152,  184,  152,  130,  151,  184,  152,  214,  152,   15,
- /*  1240 */   194,  187,  226,  194,  187,  152,  187,  184,  187,   33,
- /*  1250 */   152,  214,  152,  234,  137,  159,  235,  175,    1,  237,
- /*  1260 */   175,  237,   20,  112,  112,  112,   92,  112,  107,   19,
- /*  1270 */    11,   20,   20,  231,   19,   19,   22,  117,  240,  117,
- /*  1280 */    20,   20,   20,  114,   19,   22,   22,   20,  112,   20,
- /*  1290 */    20,   44,   19,  243,   19,   96,   20,   44,  246,   19,
- /*  1300 */    32,   19,   44,   19,  103,   16,   21,   17,   36,   98,
- /*  1310 */    22,  133,   98,   19,    5,    1,   45,   51,  122,   45,
- /*  1320 */   102,   19,  113,  115,   14,   17,  113,  102,  122,   14,
- /*  1330 */    19,  136,   20,  135,    3,  123,   57,   19,    4,  247,
- /*  1340 */   247,  247,  247,  247,  247,   68,   68,
+ /*   280 */    72,  148,   74,   75,   76,   77,   78,   79,   80,   81,
+ /*   290 */    82,   83,   84,   42,   43,  186,  187,   16,   49,  148,
+ /*   300 */   201,   49,   18,  170,  171,  154,  142,  143,  157,  158,
+ /*   310 */   182,   60,   61,   62,   63,   64,   65,   66,   67,   68,
+ /*   320 */    69,   70,   71,   72,   91,   74,   75,   76,   77,   78,
+ /*   330 */    79,   80,   81,   82,   83,   84,  168,  169,  122,   55,
+ /*   340 */   132,   16,   16,  110,   16,  177,   20,   20,   99,  100,
+ /*   350 */   101,   99,  100,  101,   80,   12,  223,  124,  148,  110,
+ /*   360 */   182,  148,  110,   23,   19,   84,   21,   24,   42,   43,
+ /*   370 */   148,   90,   91,   92,   93,   94,   95,   96,   94,  166,
+ /*   380 */    37,  107,   39,  132,  103,  111,   60,   61,   62,   63,
+ /*   390 */    64,   65,   66,   67,   68,   69,   70,   71,   72,  189,
+ /*   400 */    74,   75,   76,   77,   78,   79,   80,   81,   82,   83,
+ /*   410 */    84,   16,   84,  156,   92,   20,   23,   92,  134,   91,
+ /*   420 */    92,   93,   94,   95,   96,  103,  148,   22,   88,   89,
+ /*   430 */   148,  103,  210,  106,  156,  108,  109,   42,   43,  144,
+ /*   440 */   145,  228,  229,  219,  149,  221,  222,  190,  170,  171,
+ /*   450 */   240,  156,  170,  171,  162,   60,   61,   62,   63,   64,
+ /*   460 */    65,   66,   67,   68,   69,   70,   71,   72,  190,   74,
+ /*   470 */    75,   76,   77,   78,   79,   80,   81,   82,   83,   84,
+ /*   480 */    16,   88,   89,   90,   20,  190,   93,   94,   95,   23,
+ /*   490 */   131,  213,  133,  201,  212,   90,  218,  104,   93,   94,
+ /*   500 */    95,   42,   43,    7,    8,    9,   42,   43,  191,  104,
+ /*   510 */   215,  219,  159,  221,  222,  162,  163,  164,  156,  165,
+ /*   520 */   166,  167,   63,   64,   60,   61,   62,   63,   64,   65,
+ /*   530 */    66,   67,   68,   69,   70,   71,   72,  242,   74,   75,
+ /*   540 */    76,   77,   78,   79,   80,   81,   82,   83,   84,   16,
+ /*   550 */   148,   92,  190,   20,   88,   89,  148,   90,  156,  148,
+ /*   560 */    93,   94,   95,   20,  187,  148,   19,   20,  148,   22,
+ /*   570 */    19,  104,  170,  171,   23,   42,   43,  148,  170,  171,
+ /*   580 */   114,  170,  171,  229,   99,  100,  101,  170,  171,  148,
+ /*   590 */   170,  171,  190,   60,   61,   62,   63,   64,   65,   66,
+ /*   600 */    67,   68,   69,   70,   71,   72,   59,   74,   75,   76,
+ /*   610 */    77,   78,   79,   80,   81,   82,   83,   84,   16,  211,
+ /*   620 */   212,   12,  148,   21,  213,  165,  166,  167,   21,  148,
+ /*   630 */    23,  148,  148,   24,  217,   19,   20,  217,   22,   88,
+ /*   640 */    89,  157,  158,  214,   42,   43,   37,  148,   39,  106,
+ /*   650 */   148,  108,  109,  170,  171,   20,  146,  183,   49,  156,
+ /*   660 */    14,   16,   60,   61,   62,   63,   64,   65,   66,   67,
+ /*   670 */    68,   69,   70,   71,   72,   59,   74,   75,   76,   77,
+ /*   680 */    78,   79,   80,   81,   82,   83,   84,   42,   43,  229,
+ /*   690 */    99,  100,  101,  190,  106,   88,  108,  109,   52,   14,
+ /*   700 */    54,  148,  156,  162,   16,   60,   61,   62,   63,   64,
+ /*   710 */    65,   66,   67,   68,   69,   70,   71,   72,  215,   74,
+ /*   720 */    75,   76,   77,   78,   79,   80,   81,   82,   83,   84,
+ /*   730 */    42,   43,  245,  246,  148,  148,  190,   52,  193,   54,
+ /*   740 */   237,  106,  201,  108,  109,  200,  148,   16,   60,   61,
+ /*   750 */    62,   63,   64,   65,   66,   67,   68,   69,   70,   71,
+ /*   760 */    72,  215,   74,   75,   76,   77,   78,   79,   80,   81,
+ /*   770 */    82,   83,   84,   42,   43,   25,  189,   22,  232,   29,
+ /*   780 */   134,  183,   16,  237,  202,  203,  148,  148,  192,  148,
+ /*   790 */    16,   41,   61,   62,   63,   64,   65,   66,   67,   68,
+ /*   800 */    69,   70,   71,   72,  148,   74,   75,   76,   77,   78,
+ /*   810 */    79,   80,   81,   82,   83,   84,   42,   43,   23,   19,
+ /*   820 */    23,  183,  148,   23,  148,  148,  170,  171,  189,   19,
+ /*   830 */   189,  107,  148,   23,  148,  111,   62,   63,   64,   65,
+ /*   840 */    66,   67,   68,   69,   70,   71,   72,  148,   74,   75,
+ /*   850 */    76,   77,   78,   79,   80,   81,   82,   83,   84,   16,
+ /*   860 */    17,  148,   19,  189,  148,  189,   23,  148,  113,  170,
+ /*   870 */   171,  148,   16,  148,   31,   16,   17,   80,   19,  162,
+ /*   880 */   148,  115,   23,   88,   89,   88,   89,  210,   88,   89,
+ /*   890 */    31,   48,  148,  170,  171,  170,  171,  148,   88,   43,
+ /*   900 */   214,   58,  170,  171,  148,  189,  148,   48,  189,  114,
+ /*   910 */    19,  148,  243,  244,  170,  171,  148,   58,  148,  170,
+ /*   920 */   171,   78,   79,  210,  148,   30,  170,  171,  170,  171,
+ /*   930 */    87,   88,   89,  170,  171,   92,  148,   78,   79,   80,
+ /*   940 */   170,  171,  125,  126,  148,   50,   87,   88,   89,   16,
+ /*   950 */    17,   92,   19,  110,   98,  148,   23,  148,  156,  103,
+ /*   960 */   148,  110,  156,   22,   31,  189,  170,  171,  125,  126,
+ /*   970 */   127,  128,  129,  130,   20,  124,  156,  170,  171,  170,
+ /*   980 */   171,   48,  170,  171,  125,  126,  127,  128,  129,  130,
+ /*   990 */   204,   58,  190,    5,  148,  148,  190,  102,   10,   11,
+ /*  1000 */    12,   13,  148,  112,   22,  148,  148,   20,  148,   22,
+ /*  1010 */   190,   78,   79,   59,   26,   43,   28,  170,  171,  148,
+ /*  1020 */    87,   88,   89,   35,  148,   92,  148,  170,  171,  148,
+ /*  1030 */   170,  171,  148,   27,  148,   47,  148,   49,   97,  234,
+ /*  1040 */    34,   53,  148,  179,   56,  148,  170,  171,  170,  171,
+ /*  1050 */   148,  170,  171,  148,  170,  171,  170,  171,  125,  126,
+ /*  1060 */   127,  128,  129,  130,  170,  171,  179,  170,  171,  148,
+ /*  1070 */    98,   89,  170,  171,  148,  170,  171,  148,   20,  148,
+ /*  1080 */    22,   20,  148,   22,  148,  179,  148,   99,  100,  101,
+ /*  1090 */   148,  170,  171,  105,  148,  148,  114,  148,  110,  170,
+ /*  1100 */   171,  170,  171,  148,  170,  171,  170,  171,  170,  171,
+ /*  1110 */     7,    8,  170,  171,   20,  148,   22,  170,  171,  170,
+ /*  1120 */   171,  148,   20,  135,   22,  170,  171,  148,  148,   91,
+ /*  1130 */    92,   20,   20,   22,   22,  150,  233,  170,  171,   20,
+ /*  1140 */    20,   22,   22,  170,  171,   20,  148,   22,  148,  170,
+ /*  1150 */   171,  148,  148,  148,  192,  148,  148,  148,  148,  148,
+ /*  1160 */   148,  148,  148,  148,  148,  148,  173,  230,  194,  230,
+ /*  1170 */   225,  205,  173,  178,  173,  173,  195,    6,  147,  195,
+ /*  1180 */   162,  162,  205,  162,  147,   22,  147,  147,  205,  155,
+ /*  1190 */   122,  195,  119,  173,  120,  118,  174,  121,  131,  224,
+ /*  1200 */   112,  153,  153,   98,  117,   98,   40,  172,  172,   19,
+ /*  1210 */    97,   84,   15,  190,  172,  152,  172,  174,  227,  227,
+ /*  1220 */   196,  180,  197,  172,  198,  175,  199,  180,  172,  172,
+ /*  1230 */   175,  153,  152,  152,  206,  153,  207,  207,  206,  153,
+ /*  1240 */    38,  131,  153,  152,   60,  153,   19,  185,  195,  185,
+ /*  1250 */   153,   15,  153,  188,  188,  195,  185,  188,  188,   33,
+ /*  1260 */   138,  153,  216,    1,  160,   20,  176,  153,  235,  176,
+ /*  1270 */   216,  112,  112,  112,  112,   92,  107,   19,   11,   20,
+ /*  1280 */    20,  236,   19,   19,  116,   20,  116,  114,   22,   20,
+ /*  1290 */   238,   20,   22,   19,   22,  116,  115,  238,   20,  112,
+ /*  1300 */    20,   20,   19,   19,   19,   32,   20,   19,   19,   96,
+ /*  1310 */   103,   16,   44,  241,   17,   21,   98,   98,   36,  244,
+ /*  1320 */    44,   44,   22,  134,   19,    5,  247,    1,  123,   68,
+ /*  1330 */    51,  102,   45,   19,  113,   45,    1,   14,   17,  117,
+ /*  1340 */   102,  113,   20,   68,   19,   14,  123,  136,  124,   57,
+ /*  1350 */     3,  137,   19,    4,
 };
-#define YY_SHIFT_USE_DFLT (-62)
-#define YY_SHIFT_MAX 389
+#define YY_SHIFT_USE_DFLT (-99)
+#define YY_SHIFT_MAX 396
 static const short yy_shift_ofst[] = {
- /*     0 */    39,  841,  986,  -16,  841,  931,  931,  258,  123,  -36,
- /*    10 */    96,  931,  931,  931,  931,  931,  -45,  400,  174,   19,
- /*    20 */   171,  -54,  -54,   53,  165,  208,  251,  324,  393,  462,
- /*    30 */   531,  600,  643,  686,  643,  643,  643,  643,  643,  643,
- /*    40 */   643,  643,  643,  643,  643,  643,  643,  643,  643,  643,
- /*    50 */   643,  643,  729,  772,  772,  857,  931,  931,  931,  931,
- /*    60 */   931,  931,  931,  931,  931,  931,  931,  931,  931,  931,
- /*    70 */   931,  931,  931,  931,  931,  931,  931,  931,  931,  931,
- /*    80 */   931,  931,  931,  931,  931,  931,  931,  931,  931,  931,
- /*    90 */   931,  931,  931,  931,  931,  931,  -61,  -61,    6,    6,
- /*   100 */   280,   22,   61,  399,  564,   19,   19,   19,   19,   19,
- /*   110 */    19,   19,  216,  171,   63,  -62,  -62,  -62,  131,  326,
- /*   120 */   472,  472,  498,  559,  506,  799,   19,  799,   19,   19,
- /*   130 */    19,   19,   19,   19,   19,   19,   19,   19,   19,   19,
- /*   140 */    19,  849,   95,  -36,  -36,  -36,  -62,  -62,  -62,  -15,
- /*   150 */   -15,  333,  459,  478,  557,  530,  541,  616,  602,  793,
- /*   160 */   604,  607,  626,   19,   19,  881,   19,   19,  994,   19,
- /*   170 */    19,  807,   19,   19,  673,  807,   19,   19,  384,  384,
- /*   180 */   384,   19,   19,  673,   19,   19,  673,   19,  454,  685,
- /*   190 */    19,   19,  673,   19,   19,   19,  673,   19,   19,   19,
- /*   200 */   673,  673,   19,   19,   19,   19,   19,  468,  883,  921,
- /*   210 */   171,  754,  754,  432,  406,  406,  406,  816,  406,  171,
- /*   220 */   406,  171,  811,  879,  879, 1166, 1166, 1166, 1166, 1154,
- /*   230 */   -36, 1060, 1065, 1066, 1068, 1069, 1056, 1076, 1076, 1095,
- /*   240 */  1079, 1095, 1079, 1097, 1097, 1157, 1097, 1105, 1097, 1182,
- /*   250 */  1119, 1119, 1157, 1097, 1097, 1097, 1182, 1189, 1076, 1189,
- /*   260 */  1076, 1189, 1076, 1076, 1179, 1103, 1189, 1076, 1167, 1167,
- /*   270 */  1210, 1060, 1076, 1224, 1224, 1224, 1224, 1060, 1167, 1210,
- /*   280 */  1076, 1216, 1216, 1076, 1076, 1117,  -62,  -62,  -62,  -62,
- /*   290 */   -62,  -62,  525,  684,  727,  168,  894,  556,  555,  938,
- /*   300 */   944,  949,  912, 1058, 1073, 1087, 1091, 1101, 1104, 1108,
- /*   310 */  1030, 1116, 1099, 1257, 1242, 1151, 1152, 1153, 1155, 1174,
- /*   320 */  1161, 1250, 1251, 1252, 1255, 1259, 1256, 1260, 1254, 1261,
- /*   330 */  1262, 1263, 1160, 1264, 1162, 1263, 1169, 1265, 1267, 1176,
- /*   340 */  1269, 1270, 1268, 1247, 1273, 1253, 1275, 1276, 1280, 1282,
- /*   350 */  1258, 1284, 1199, 1201, 1289, 1290, 1285, 1211, 1272, 1266,
- /*   360 */  1271, 1288, 1274, 1178, 1214, 1294, 1309, 1314, 1218, 1277,
- /*   370 */  1278, 1196, 1302, 1209, 1310, 1208, 1308, 1213, 1225, 1206,
- /*   380 */  1311, 1212, 1312, 1315, 1279, 1198, 1195, 1318, 1331, 1334,
+ /*     0 */    23,  843,  988,  -16,  843,  933,  933,  393,  123,  252,
+ /*    10 */   -98,   96,  933,  933,  933,  933,  933,  -45,  249,  174,
+ /*    20 */   340,  -17,   19,   19,   53,  165,  208,  251,  326,  395,
+ /*    30 */   464,  533,  602,  645,  688,  645,  645,  645,  645,  645,
+ /*    40 */   645,  645,  645,  645,  645,  645,  645,  645,  645,  645,
+ /*    50 */   645,  645,  645,  731,  774,  774,  859,  933,  933,  933,
+ /*    60 */   933,  933,  933,  933,  933,  933,  933,  933,  933,  933,
+ /*    70 */   933,  933,  933,  933,  933,  933,  933,  933,  933,  933,
+ /*    80 */   933,  933,  933,  933,  933,  933,  933,  933,  933,  933,
+ /*    90 */   933,  933,  933,  933,  933,  933,  933,  -61,  -61,    6,
+ /*   100 */     6,  281,   22,   61,  856,  284,  340,  340,   68,  -17,
+ /*   110 */   -11,  -99,  -99,  -99,  131,  328,  609,  609,  547,  616,
+ /*   120 */   253,  607,  340,  607,  340,  340,  340,  340,  340,  340,
+ /*   130 */   340,  340,  340,  340,  340,  340,  340,  340,  340,  340,
+ /*   140 */   340,  233,  851,  -98,  -98,  -98,  -99,  -99,  -99,  -18,
+ /*   150 */   -18,  405,  467,  327,  551,  543,  635,  343,  466,  795,
+ /*   160 */   800,  797,  496,  340,  340,  274,  340,  340,  810,  340,
+ /*   170 */   340,  982,  340,  340,  340,  588,  982,  340,  340,  895,
+ /*   180 */   895,  895,  340,  340,  340,  588,  340,  340,  588,  340,
+ /*   190 */   750,  485,  340,  340,  588,  340,  340,  340,  588,  340,
+ /*   200 */   340,  340,  588,  588,  340,  340,  340,  340,  340,  345,
+ /*   210 */   724,  755,  -17,  817,  817,  359, 1006, 1006,  766, 1006,
+ /*   220 */   972, 1006,  -17, 1006,  -17,  941,  216,  766,  766,  216,
+ /*   230 */  1171, 1171, 1171, 1171, 1163,  -98, 1068, 1073, 1074, 1077,
+ /*   240 */  1076, 1067, 1088, 1088, 1105, 1087, 1105, 1087, 1107, 1107,
+ /*   250 */  1166, 1107, 1113, 1107, 1190, 1127, 1127, 1166, 1107, 1107,
+ /*   260 */  1107, 1190, 1197, 1088, 1197, 1088, 1197, 1088, 1088, 1202,
+ /*   270 */  1110, 1197, 1088, 1184, 1184, 1227, 1068, 1088, 1236, 1236,
+ /*   280 */  1236, 1236, 1068, 1184, 1227, 1088, 1226, 1226, 1088, 1088,
+ /*   290 */  1122,  -99,  -99,  -99,  -99,  -99,  459,  646,  591,  685,
+ /*   300 */   891,  325,  987, 1058,  322, 1103, 1038, 1061, 1094, 1102,
+ /*   310 */  1111, 1112, 1119, 1120,  150, 1125,  954, 1262, 1245, 1159,
+ /*   320 */  1160, 1161, 1162, 1183, 1169, 1258, 1259, 1260, 1263, 1267,
+ /*   330 */  1264, 1265, 1266, 1269, 1271, 1270, 1168, 1272, 1170, 1270,
+ /*   340 */  1173, 1274, 1179, 1181, 1278, 1187, 1280, 1281, 1273, 1268,
+ /*   350 */  1283, 1276, 1284, 1286, 1285, 1288, 1277, 1289, 1213, 1207,
+ /*   360 */  1295, 1297, 1294, 1218, 1282, 1279, 1287, 1300, 1290, 1189,
+ /*   370 */  1219, 1305, 1320, 1326, 1229, 1261, 1275, 1205, 1314, 1221,
+ /*   380 */  1335, 1323, 1222, 1321, 1228, 1238, 1223, 1325, 1224, 1322,
+ /*   390 */  1331, 1292, 1211, 1214, 1333, 1347, 1349,
 };
-#define YY_REDUCE_USE_DFLT (-165)
-#define YY_REDUCE_MAX 291
+#define YY_REDUCE_USE_DFLT (-144)
+#define YY_REDUCE_MAX 295
 static const short yy_reduce_ofst[] = {
- /*     0 */  -138,  277,  546,  137,  401,  -21,   44,   36,   38,  242,
- /*    10 */  -141,  191,   91,  269,  343,  345, -126,  589,  338,  150,
- /*    20 */   147,  -13,  213,  412,  412,  412,  412,  412,  412,  412,
- /*    30 */   412,  412,  412,  412,  412,  412,  412,  412,  412,  412,
- /*    40 */   412,  412,  412,  412,  412,  412,  412,  412,  412,  412,
- /*    50 */   412,  412,  412,  412,  412,  211,  698,  714,  716,  722,
- /*    60 */   724,  728,  748,  753,  755,  757,  762,  769,  794,  805,
- /*    70 */   808,  846,  855,  858,  861,  875,  882,  893,  896,  899,
- /*    80 */   901,  903,  906,  920,  930,  932,  934,  936,  945,  947,
- /*    90 */   963,  965,  971,  975,  978,  980,  412,  412,  412,  412,
- /*   100 */    20,  412,  412,   23,   34,  334,  475,  552,  593,  594,
- /*   110 */   585,  212,  412,  289,  412,  412,  412,  412,  135, -164,
- /*   120 */  -115,  164,  407,  407,  350,  141,  436,  163,  596,  -90,
- /*   130 */   763,  218,  765,  438,  586,  592,  595,  715,  718,  408,
- /*   140 */   723,  380,  634,  677,  787,  798,  144,  529,  588,  -14,
- /*   150 */     0,   17,  244,  155,  298,  155,  155,  418,  372,  477,
- /*   160 */   490,  494,  509,  526,  590,  465,  494,  730,  773,  743,
- /*   170 */   833,  792,  854,  860,  155,  792,  864,  885,  848,  859,
- /*   180 */   863,  891,  907,  155,  914,  917,  155,  927,  852,  898,
- /*   190 */   941,  950,  155,  961,  982,  990,  155,  992,  995,  996,
- /*   200 */   155,  155,  999, 1004, 1005, 1006, 1007, 1008,  964,  966,
- /*   210 */  1000,  933,  935,  937,  984,  991,  993,  989,  997, 1009,
- /*   220 */  1001, 1010, 1002,  973,  974, 1028, 1031, 1032, 1033, 1026,
- /*   230 */   998,  988, 1003, 1011, 1012, 1013,  968, 1039, 1040, 1014,
- /*   240 */  1015, 1017, 1018, 1025, 1029, 1020, 1034, 1035, 1041, 1036,
- /*   250 */   987, 1016, 1027, 1043, 1044, 1045, 1048, 1074, 1067, 1075,
- /*   260 */  1072, 1077, 1078, 1080, 1019, 1021, 1083, 1084, 1047, 1051,
- /*   270 */  1023, 1046, 1086, 1054, 1057, 1059, 1061, 1049, 1063, 1037,
- /*   280 */  1093, 1022, 1024, 1098, 1100, 1038, 1096, 1082, 1085, 1042,
- /*   290 */  1050, 1052,
+ /*     0 */  -139,  278,  295,  292,  402,  -22,  408,   35,   37,  546,
+ /*    10 */    -3, -128,  133,  282,  411,  417,  420, -143,  503,  213,
+ /*    20 */   151,  353,  354,  460,  224,  224,  224,  224,  224,  224,
+ /*    30 */   224,  224,  224,  224,  224,  224,  224,  224,  224,  224,
+ /*    40 */   224,  224,  224,  224,  224,  224,  224,  224,  224,  224,
+ /*    50 */   224,  224,  224,  224,  224,  224,  483,  656,  699,  723,
+ /*    60 */   725,  732,  744,  749,  756,  758,  763,  770,  796,  807,
+ /*    70 */   809,  812,  847,  857,  860,  876,  878,  881,  884,  886,
+ /*    80 */   894,  897,  902,  905,  921,  929,  931,  934,  936,  938,
+ /*    90 */   942,  947,  949,  955,  967,  973,  979,  224,  224,  224,
+ /*   100 */   224,  168,  224,  224,   36,   33,  210,  484,  224, -121,
+ /*   110 */   224,  224,  224,  224,   45,   21,    8,  109,  487,  487,
+ /*   120 */   164,   99,  222,  541,  -91,   -1,  474,  598,  587,  677,
+ /*   130 */   638,  429,  713,  639,  641,  674,  676,  716,  719,  686,
+ /*   140 */   776,  257,  362,  802,  806,  820,  545,  582,  669,  -60,
+ /*   150 */   -15,  128,  178,  317,   40,  317,  317,  377,  441,  481,
+ /*   160 */   499,  502,  510,  553,  586,  596,  502,  684,  717,  768,
+ /*   170 */   788,  786,  846,  854,  858,  317,  786,  871,  888,  864,
+ /*   180 */   887,  906,  926,  946,  980,  317,  998, 1000,  317, 1003,
+ /*   190 */   903,  805, 1004, 1005,  317, 1007, 1008, 1009,  317, 1010,
+ /*   200 */  1011, 1012,  317,  317, 1013, 1014, 1015, 1016, 1017,  985,
+ /*   210 */   962,  974, 1018,  937,  939,  945,  993,  999,  966, 1001,
+ /*   220 */   995, 1002, 1019, 1020, 1021, 1022,  981,  977,  983,  984,
+ /*   230 */  1031, 1037, 1039, 1040, 1034, 1023,  996, 1024, 1025, 1026,
+ /*   240 */  1027,  975, 1048, 1049, 1028, 1029, 1032, 1030, 1035, 1036,
+ /*   250 */  1041, 1042, 1043, 1044, 1050,  991,  992, 1047, 1051, 1056,
+ /*   260 */  1057, 1055, 1063, 1078, 1080, 1082, 1081, 1086, 1089, 1033,
+ /*   270 */  1045, 1091, 1092, 1062, 1064, 1046, 1053, 1097, 1065, 1066,
+ /*   280 */  1069, 1070, 1060, 1071, 1054, 1099, 1052, 1059, 1108, 1114,
+ /*   290 */  1072, 1104, 1090, 1093, 1075, 1079,
 };
 static const YYACTIONTYPE yy_default[] = {
- /*     0 */   594,  819,  900,  709,  900,  819,  900,  900,  846,  713,
- /*    10 */   875,  817,  900,  900,  900,  900,  791,  900,  846,  900,
- /*    20 */   625,  846,  846,  742,  900,  900,  900,  900,  900,  900,
- /*    30 */   900,  900,  743,  900,  821,  816,  812,  814,  813,  820,
- /*    40 */   744,  733,  740,  747,  725,  859,  749,  750,  756,  757,
- /*    50 */   876,  874,  779,  778,  797,  900,  900,  900,  900,  900,
- /*    60 */   900,  900,  900,  900,  900,  900,  900,  900,  900,  900,
- /*    70 */   900,  900,  900,  900,  900,  900,  900,  900,  900,  900,
- /*    80 */   900,  900,  900,  900,  900,  900,  900,  900,  900,  900,
- /*    90 */   900,  900,  900,  900,  900,  900,  781,  803,  780,  790,
- /*   100 */   618,  782,  783,  678,  613,  900,  900,  900,  900,  900,
- /*   110 */   900,  900,  784,  900,  785,  798,  799,  800,  900,  900,
- /*   120 */   900,  900,  900,  900,  594,  709,  900,  709,  900,  900,
- /*   130 */   900,  900,  900,  900,  900,  900,  900,  900,  900,  900,
- /*   140 */   900,  900,  900,  900,  900,  900,  703,  713,  893,  900,
- /*   150 */   900,  669,  900,  900,  900,  900,  900,  900,  900,  900,
- /*   160 */   900,  900,  601,  599,  900,  701,  900,  900,  627,  900,
- /*   170 */   900,  711,  900,  900,  716,  717,  900,  900,  900,  900,
- /*   180 */   900,  900,  900,  615,  900,  900,  690,  900,  852,  900,
- /*   190 */   900,  900,  866,  900,  900,  900,  864,  900,  900,  900,
- /*   200 */   692,  752,  833,  900,  879,  881,  900,  900,  701,  710,
- /*   210 */   900,  900,  900,  815,  736,  736,  736,  648,  736,  900,
- /*   220 */   736,  900,  651,  746,  746,  598,  598,  598,  598,  668,
- /*   230 */   900,  746,  737,  739,  729,  741,  900,  718,  718,  726,
- /*   240 */   728,  726,  728,  680,  680,  665,  680,  651,  680,  825,
- /*   250 */   830,  830,  665,  680,  680,  680,  825,  610,  718,  610,
- /*   260 */   718,  610,  718,  718,  856,  858,  610,  718,  682,  682,
- /*   270 */   758,  746,  718,  689,  689,  689,  689,  746,  682,  758,
- /*   280 */   718,  878,  878,  718,  718,  886,  635,  653,  653,  861,
- /*   290 */   893,  898,  900,  900,  900,  900,  765,  900,  900,  900,
- /*   300 */   900,  900,  900,  900,  900,  900,  900,  900,  900,  900,
- /*   310 */   839,  900,  900,  900,  900,  770,  766,  900,  767,  900,
- /*   320 */   695,  900,  900,  900,  900,  900,  900,  900,  900,  900,
- /*   330 */   900,  818,  900,  730,  900,  738,  900,  900,  900,  900,
- /*   340 */   900,  900,  900,  900,  900,  900,  900,  900,  900,  900,
- /*   350 */   900,  900,  900,  900,  900,  900,  900,  900,  900,  900,
- /*   360 */   854,  855,  900,  900,  900,  900,  900,  900,  900,  900,
- /*   370 */   900,  900,  900,  900,  900,  900,  900,  900,  900,  900,
- /*   380 */   900,  900,  900,  900,  885,  900,  900,  888,  595,  900,
- /*   390 */   589,  592,  591,  593,  597,  600,  622,  623,  624,  602,
- /*   400 */   603,  604,  605,  606,  607,  608,  614,  616,  634,  636,
- /*   410 */   620,  638,  699,  700,  762,  693,  694,  698,  621,  773,
- /*   420 */   764,  768,  769,  771,  772,  786,  787,  789,  795,  802,
- /*   430 */   805,  788,  793,  794,  796,  801,  804,  696,  697,  808,
- /*   440 */   628,  629,  632,  633,  842,  844,  843,  845,  631,  630,
- /*   450 */   774,  777,  810,  811,  867,  868,  869,  870,  871,  806,
- /*   460 */   719,  809,  792,  731,  734,  735,  732,  702,  712,  721,
- /*   470 */   722,  723,  724,  707,  708,  714,  727,  760,  761,  715,
- /*   480 */   704,  705,  706,  807,  763,  775,  776,  639,  640,  770,
- /*   490 */   641,  642,  643,  681,  684,  685,  686,  644,  663,  666,
- /*   500 */   667,  645,  652,  646,  647,  654,  655,  656,  659,  660,
- /*   510 */   661,  662,  657,  658,  826,  827,  831,  829,  828,  649,
- /*   520 */   650,  664,  637,  626,  619,  670,  673,  674,  675,  676,
- /*   530 */   677,  679,  671,  672,  617,  609,  611,  720,  848,  857,
- /*   540 */   853,  849,  850,  851,  612,  822,  823,  683,  754,  755,
- /*   550 */   847,  860,  862,  759,  863,  865,  890,  687,  688,  691,
- /*   560 */   832,  872,  745,  748,  751,  753,  834,  835,  836,  837,
- /*   570 */   840,  841,  838,  873,  877,  880,  882,  883,  884,  887,
- /*   580 */   889,  894,  895,  896,  899,  897,  596,  590,
+ /*     0 */   603,  832,  913,  719,  913,  832,  913,  913,  859,  913,
+ /*    10 */   723,  888,  830,  913,  913,  913,  913,  804,  913,  859,
+ /*    20 */   913,  635,  859,  859,  755,  913,  913,  913,  913,  913,
+ /*    30 */   913,  913,  913,  756,  913,  834,  829,  825,  827,  826,
+ /*    40 */   833,  757,  746,  753,  760,  735,  872,  762,  763,  769,
+ /*    50 */   770,  889,  887,  792,  791,  810,  913,  913,  913,  913,
+ /*    60 */   913,  913,  913,  913,  913,  913,  913,  913,  913,  913,
+ /*    70 */   913,  913,  913,  913,  913,  913,  913,  913,  913,  913,
+ /*    80 */   913,  913,  913,  913,  913,  913,  913,  913,  913,  913,
+ /*    90 */   913,  913,  913,  913,  913,  913,  913,  794,  816,  793,
+ /*   100 */   803,  628,  795,  796,  688,  623,  913,  913,  797,  913,
+ /*   110 */   798,  811,  812,  813,  913,  913,  913,  913,  913,  913,
+ /*   120 */   603,  719,  913,  719,  913,  913,  913,  913,  913,  913,
+ /*   130 */   913,  913,  913,  913,  913,  913,  913,  913,  913,  913,
+ /*   140 */   913,  913,  913,  913,  913,  913,  713,  723,  906,  913,
+ /*   150 */   913,  679,  913,  913,  913,  913,  913,  913,  913,  913,
+ /*   160 */   913,  913,  611,  609,  913,  711,  913,  913,  637,  913,
+ /*   170 */   913,  721,  913,  913,  913,  726,  727,  913,  913,  913,
+ /*   180 */   913,  913,  913,  913,  913,  625,  913,  913,  700,  913,
+ /*   190 */   865,  913,  913,  913,  879,  913,  913,  913,  877,  913,
+ /*   200 */   913,  913,  702,  765,  845,  913,  892,  894,  913,  913,
+ /*   210 */   711,  720,  913,  913,  913,  828,  749,  749,  737,  749,
+ /*   220 */   658,  749,  913,  749,  913,  661,  759,  737,  737,  759,
+ /*   230 */   608,  608,  608,  608,  678,  913,  759,  750,  752,  742,
+ /*   240 */   754,  913,  728,  728,  736,  741,  736,  741,  690,  690,
+ /*   250 */   675,  690,  661,  690,  838,  842,  842,  675,  690,  690,
+ /*   260 */   690,  838,  620,  728,  620,  728,  620,  728,  728,  869,
+ /*   270 */   871,  620,  728,  692,  692,  771,  759,  728,  699,  699,
+ /*   280 */   699,  699,  759,  692,  771,  728,  891,  891,  728,  728,
+ /*   290 */   899,  645,  663,  663,  906,  911,  913,  913,  913,  913,
+ /*   300 */   778,  913,  913,  913,  913,  913,  913,  913,  913,  913,
+ /*   310 */   913,  913,  913,  913,  852,  913,  913,  913,  913,  783,
+ /*   320 */   779,  913,  780,  913,  705,  913,  913,  913,  913,  913,
+ /*   330 */   913,  913,  913,  913,  913,  831,  913,  743,  913,  751,
+ /*   340 */   913,  913,  913,  913,  913,  913,  913,  913,  913,  913,
+ /*   350 */   913,  913,  913,  913,  913,  913,  913,  913,  913,  913,
+ /*   360 */   913,  913,  913,  913,  913,  913,  867,  868,  913,  913,
+ /*   370 */   913,  913,  913,  913,  913,  913,  913,  913,  913,  913,
+ /*   380 */   913,  913,  913,  913,  913,  913,  913,  913,  913,  913,
+ /*   390 */   913,  898,  913,  913,  901,  604,  913,  599,  601,  602,
+ /*   400 */   606,  607,  610,  632,  633,  634,  612,  613,  614,  615,
+ /*   410 */   616,  617,  618,  624,  626,  644,  646,  630,  648,  709,
+ /*   420 */   710,  775,  703,  704,  708,  631,  786,  777,  781,  782,
+ /*   430 */   784,  785,  799,  800,  802,  808,  815,  818,  801,  806,
+ /*   440 */   807,  809,  814,  817,  706,  707,  821,  638,  639,  642,
+ /*   450 */   643,  855,  857,  856,  858,  641,  640,  787,  790,  823,
+ /*   460 */   824,  880,  881,  882,  883,  884,  819,  729,  822,  805,
+ /*   470 */   744,  747,  748,  745,  712,  722,  731,  732,  733,  734,
+ /*   480 */   717,  718,  724,  740,  773,  774,  738,  739,  725,  714,
+ /*   490 */   715,  716,  820,  776,  788,  789,  649,  650,  783,  651,
+ /*   500 */   652,  653,  691,  694,  695,  696,  654,  673,  676,  677,
+ /*   510 */   655,  662,  656,  657,  664,  665,  666,  669,  670,  671,
+ /*   520 */   672,  667,  668,  839,  840,  843,  841,  659,  660,  674,
+ /*   530 */   647,  636,  629,  680,  683,  684,  685,  686,  687,  689,
+ /*   540 */   681,  682,  627,  619,  621,  730,  861,  870,  866,  862,
+ /*   550 */   863,  864,  622,  835,  836,  693,  767,  768,  860,  873,
+ /*   560 */   875,  772,  876,  878,  874,  903,  697,  698,  701,  844,
+ /*   570 */   885,  758,  761,  764,  766,  846,  847,  848,  849,  850,
+ /*   580 */   853,  854,  851,  886,  890,  893,  895,  896,  897,  900,
+ /*   590 */   902,  907,  908,  909,  912,  910,  605,  600,
 };
 #define YY_SZ_ACTTAB (int)(sizeof(yy_action)/sizeof(yy_action[0]))
 
@@ -71330,7 +79417,7 @@ static const YYACTIONTYPE yy_default[] = {
 ** 
 **      %fallback ID X Y Z.
 **
-** appears in the grammer, then ID becomes a fallback token for X, Y,
+** appears in the grammar, then ID becomes a fallback token for X, Y,
 ** and Z.  Whenever one of the tokens X, Y, or Z is input to the parser
 ** but it does not parse, the type of the token is changed to ID and
 ** the parse is retried before an error is thrown.
@@ -71452,9 +79539,10 @@ static const YYCODETYPE yyFallback[] = {
     0,  /*        DOT => nothing */
     0,  /*       FROM => nothing */
     0,  /*       JOIN => nothing */
+    0,  /*    INDEXED => nothing */
+    0,  /*         BY => nothing */
     0,  /*      USING => nothing */
     0,  /*      ORDER => nothing */
-    0,  /*         BY => nothing */
     0,  /*      GROUP => nothing */
     0,  /*     HAVING => nothing */
     0,  /*      LIMIT => nothing */
@@ -71491,11 +79579,11 @@ static const YYCODETYPE yyFallback[] = {
 **      It is sometimes called the "minor" token.
 */
 struct yyStackEntry {
-  int stateno;       /* The state-number */
-  int major;         /* The major token value.  This is the code
-                     ** number for the token at this stack level */
-  YYMINORTYPE minor; /* The user-supplied minor token value.  This
-                     ** is the value of the token  */
+  YYACTIONTYPE stateno;  /* The state-number */
+  YYCODETYPE major;      /* The major token value.  This is the code
+                         ** number for the token at this stack level */
+  YYMINORTYPE minor;     /* The user-supplied minor token value.  This
+                         ** is the value of the token  */
 };
 typedef struct yyStackEntry yyStackEntry;
 
@@ -71503,6 +79591,9 @@ typedef struct yyStackEntry yyStackEntry;
 ** the following structure */
 struct yyParser {
   int yyidx;                    /* Index of top element in stack */
+#ifdef YYTRACKMAXSTACKDEPTH
+  int yyidxMax;                 /* Maximum value of yyidx */
+#endif
   int yyerrcnt;                 /* Shifts left before out of the error */
   sqlite3ParserARG_SDECL                /* A place to hold %extra_argument */
 #if YYSTACKDEPTH<=0
@@ -71577,40 +79668,40 @@ static const char *const yyTokenName[] = {
   "UPDATE",        "INSERT",        "SET",           "DEFERRABLE",  
   "FOREIGN",       "DROP",          "UNION",         "ALL",         
   "EXCEPT",        "INTERSECT",     "SELECT",        "DISTINCT",    
-  "DOT",           "FROM",          "JOIN",          "USING",       
-  "ORDER",         "BY",            "GROUP",         "HAVING",      
-  "LIMIT",         "WHERE",         "INTO",          "VALUES",      
-  "INTEGER",       "FLOAT",         "BLOB",          "REGISTER",    
-  "VARIABLE",      "CASE",          "WHEN",          "THEN",        
-  "ELSE",          "INDEX",         "ALTER",         "TO",          
-  "ADD",           "COLUMNKW",      "error",         "input",       
-  "cmdlist",       "ecmd",          "cmdx",          "cmd",         
-  "explain",       "transtype",     "trans_opt",     "nm",          
-  "create_table",  "create_table_args",  "temp",          "ifnotexists", 
-  "dbnm",          "columnlist",    "conslist_opt",  "select",      
-  "column",        "columnid",      "type",          "carglist",    
-  "id",            "ids",           "typetoken",     "typename",    
-  "signed",        "plus_num",      "minus_num",     "carg",        
-  "ccons",         "term",          "expr",          "onconf",      
-  "sortorder",     "autoinc",       "idxlist_opt",   "refargs",     
-  "defer_subclause",  "refarg",        "refact",        "init_deferred_pred_opt",
-  "conslist",      "tcons",         "idxlist",       "defer_subclause_opt",
-  "orconf",        "resolvetype",   "raisetype",     "ifexists",    
-  "fullname",      "oneselect",     "multiselect_op",  "distinct",    
-  "selcollist",    "from",          "where_opt",     "groupby_opt", 
-  "having_opt",    "orderby_opt",   "limit_opt",     "sclp",        
-  "as",            "seltablist",    "stl_prefix",    "joinop",      
-  "on_opt",        "using_opt",     "seltablist_paren",  "joinop2",     
-  "inscollist",    "sortlist",      "sortitem",      "nexprlist",   
-  "setlist",       "insert_cmd",    "inscollist_opt",  "itemlist",    
-  "exprlist",      "likeop",        "escape",        "between_op",  
-  "in_op",         "case_operand",  "case_exprlist",  "case_else",   
-  "uniqueflag",    "idxitem",       "collate",       "nmnum",       
-  "plus_opt",      "number",        "trigger_decl",  "trigger_cmd_list",
-  "trigger_time",  "trigger_event",  "foreach_clause",  "when_clause", 
-  "trigger_cmd",   "database_kw_opt",  "key_opt",       "add_column_fullname",
-  "kwcolumn_opt",  "create_vtab",   "vtabarglist",   "vtabarg",     
-  "vtabargtoken",  "lp",            "anylist",     
+  "DOT",           "FROM",          "JOIN",          "INDEXED",     
+  "BY",            "USING",         "ORDER",         "GROUP",       
+  "HAVING",        "LIMIT",         "WHERE",         "INTO",        
+  "VALUES",        "INTEGER",       "FLOAT",         "BLOB",        
+  "REGISTER",      "VARIABLE",      "CASE",          "WHEN",        
+  "THEN",          "ELSE",          "INDEX",         "ALTER",       
+  "TO",            "ADD",           "COLUMNKW",      "error",       
+  "input",         "cmdlist",       "ecmd",          "explain",     
+  "cmdx",          "cmd",           "transtype",     "trans_opt",   
+  "nm",            "create_table",  "create_table_args",  "temp",        
+  "ifnotexists",   "dbnm",          "columnlist",    "conslist_opt",
+  "select",        "column",        "columnid",      "type",        
+  "carglist",      "id",            "ids",           "typetoken",   
+  "typename",      "signed",        "plus_num",      "minus_num",   
+  "carg",          "ccons",         "term",          "expr",        
+  "onconf",        "sortorder",     "autoinc",       "idxlist_opt", 
+  "refargs",       "defer_subclause",  "refarg",        "refact",      
+  "init_deferred_pred_opt",  "conslist",      "tcons",         "idxlist",     
+  "defer_subclause_opt",  "orconf",        "resolvetype",   "raisetype",   
+  "ifexists",      "fullname",      "oneselect",     "multiselect_op",
+  "distinct",      "selcollist",    "from",          "where_opt",   
+  "groupby_opt",   "having_opt",    "orderby_opt",   "limit_opt",   
+  "sclp",          "as",            "seltablist",    "stl_prefix",  
+  "joinop",        "indexed_opt",   "on_opt",        "using_opt",   
+  "seltablist_paren",  "joinop2",       "inscollist",    "sortlist",    
+  "sortitem",      "nexprlist",     "setlist",       "insert_cmd",  
+  "inscollist_opt",  "itemlist",      "exprlist",      "likeop",      
+  "escape",        "between_op",    "in_op",         "case_operand",
+  "case_exprlist",  "case_else",     "uniqueflag",    "collate",     
+  "nmnum",         "plus_opt",      "number",        "trigger_decl",
+  "trigger_cmd_list",  "trigger_time",  "trigger_event",  "foreach_clause",
+  "when_clause",   "trigger_cmd",   "database_kw_opt",  "key_opt",     
+  "add_column_fullname",  "kwcolumn_opt",  "create_vtab",   "vtabarglist", 
+  "vtabarg",       "vtabargtoken",  "lp",            "anylist",     
 };
 #endif /* NDEBUG */
 
@@ -71621,12 +79712,12 @@ static const char *const yyRuleName[] = {
  /*   0 */ "input ::= cmdlist",
  /*   1 */ "cmdlist ::= cmdlist ecmd",
  /*   2 */ "cmdlist ::= ecmd",
- /*   3 */ "cmdx ::= cmd",
- /*   4 */ "ecmd ::= SEMI",
- /*   5 */ "ecmd ::= explain cmdx SEMI",
- /*   6 */ "explain ::=",
- /*   7 */ "explain ::= EXPLAIN",
- /*   8 */ "explain ::= EXPLAIN QUERY PLAN",
+ /*   3 */ "ecmd ::= SEMI",
+ /*   4 */ "ecmd ::= explain cmdx SEMI",
+ /*   5 */ "explain ::=",
+ /*   6 */ "explain ::= EXPLAIN",
+ /*   7 */ "explain ::= EXPLAIN QUERY PLAN",
+ /*   8 */ "cmdx ::= cmd",
  /*   9 */ "cmd ::= BEGIN transtype trans_opt",
  /*  10 */ "trans_opt ::=",
  /*  11 */ "trans_opt ::= TRANSACTION",
@@ -71744,7 +79835,7 @@ static const char *const yyRuleName[] = {
  /* 123 */ "from ::= FROM seltablist",
  /* 124 */ "stl_prefix ::= seltablist joinop",
  /* 125 */ "stl_prefix ::=",
- /* 126 */ "seltablist ::= stl_prefix nm dbnm as on_opt using_opt",
+ /* 126 */ "seltablist ::= stl_prefix nm dbnm as indexed_opt on_opt using_opt",
  /* 127 */ "seltablist ::= stl_prefix LP seltablist_paren RP as on_opt using_opt",
  /* 128 */ "seltablist_paren ::= select",
  /* 129 */ "seltablist_paren ::= seltablist",
@@ -71757,179 +79848,182 @@ static const char *const yyRuleName[] = {
  /* 136 */ "joinop ::= JOIN_KW nm nm JOIN",
  /* 137 */ "on_opt ::= ON expr",
  /* 138 */ "on_opt ::=",
- /* 139 */ "using_opt ::= USING LP inscollist RP",
- /* 140 */ "using_opt ::=",
- /* 141 */ "orderby_opt ::=",
- /* 142 */ "orderby_opt ::= ORDER BY sortlist",
- /* 143 */ "sortlist ::= sortlist COMMA sortitem sortorder",
- /* 144 */ "sortlist ::= sortitem sortorder",
- /* 145 */ "sortitem ::= expr",
- /* 146 */ "sortorder ::= ASC",
- /* 147 */ "sortorder ::= DESC",
- /* 148 */ "sortorder ::=",
- /* 149 */ "groupby_opt ::=",
- /* 150 */ "groupby_opt ::= GROUP BY nexprlist",
- /* 151 */ "having_opt ::=",
- /* 152 */ "having_opt ::= HAVING expr",
- /* 153 */ "limit_opt ::=",
- /* 154 */ "limit_opt ::= LIMIT expr",
- /* 155 */ "limit_opt ::= LIMIT expr OFFSET expr",
- /* 156 */ "limit_opt ::= LIMIT expr COMMA expr",
- /* 157 */ "cmd ::= DELETE FROM fullname where_opt",
- /* 158 */ "where_opt ::=",
- /* 159 */ "where_opt ::= WHERE expr",
- /* 160 */ "cmd ::= UPDATE orconf fullname SET setlist where_opt",
- /* 161 */ "setlist ::= setlist COMMA nm EQ expr",
- /* 162 */ "setlist ::= nm EQ expr",
- /* 163 */ "cmd ::= insert_cmd INTO fullname inscollist_opt VALUES LP itemlist RP",
- /* 164 */ "cmd ::= insert_cmd INTO fullname inscollist_opt select",
- /* 165 */ "cmd ::= insert_cmd INTO fullname inscollist_opt DEFAULT VALUES",
- /* 166 */ "insert_cmd ::= INSERT orconf",
- /* 167 */ "insert_cmd ::= REPLACE",
- /* 168 */ "itemlist ::= itemlist COMMA expr",
- /* 169 */ "itemlist ::= expr",
- /* 170 */ "inscollist_opt ::=",
- /* 171 */ "inscollist_opt ::= LP inscollist RP",
- /* 172 */ "inscollist ::= inscollist COMMA nm",
- /* 173 */ "inscollist ::= nm",
- /* 174 */ "expr ::= term",
- /* 175 */ "expr ::= LP expr RP",
- /* 176 */ "term ::= NULL",
- /* 177 */ "expr ::= ID",
- /* 178 */ "expr ::= JOIN_KW",
- /* 179 */ "expr ::= nm DOT nm",
- /* 180 */ "expr ::= nm DOT nm DOT nm",
- /* 181 */ "term ::= INTEGER|FLOAT|BLOB",
- /* 182 */ "term ::= STRING",
- /* 183 */ "expr ::= REGISTER",
- /* 184 */ "expr ::= VARIABLE",
- /* 185 */ "expr ::= expr COLLATE ids",
- /* 186 */ "expr ::= CAST LP expr AS typetoken RP",
- /* 187 */ "expr ::= ID LP distinct exprlist RP",
- /* 188 */ "expr ::= ID LP STAR RP",
- /* 189 */ "term ::= CTIME_KW",
- /* 190 */ "expr ::= expr AND expr",
- /* 191 */ "expr ::= expr OR expr",
- /* 192 */ "expr ::= expr LT|GT|GE|LE expr",
- /* 193 */ "expr ::= expr EQ|NE expr",
- /* 194 */ "expr ::= expr BITAND|BITOR|LSHIFT|RSHIFT expr",
- /* 195 */ "expr ::= expr PLUS|MINUS expr",
- /* 196 */ "expr ::= expr STAR|SLASH|REM expr",
- /* 197 */ "expr ::= expr CONCAT expr",
- /* 198 */ "likeop ::= LIKE_KW",
- /* 199 */ "likeop ::= NOT LIKE_KW",
- /* 200 */ "likeop ::= MATCH",
- /* 201 */ "likeop ::= NOT MATCH",
- /* 202 */ "escape ::= ESCAPE expr",
- /* 203 */ "escape ::=",
- /* 204 */ "expr ::= expr likeop expr escape",
- /* 205 */ "expr ::= expr ISNULL|NOTNULL",
- /* 206 */ "expr ::= expr IS NULL",
- /* 207 */ "expr ::= expr NOT NULL",
- /* 208 */ "expr ::= expr IS NOT NULL",
- /* 209 */ "expr ::= NOT expr",
- /* 210 */ "expr ::= BITNOT expr",
- /* 211 */ "expr ::= MINUS expr",
- /* 212 */ "expr ::= PLUS expr",
- /* 213 */ "between_op ::= BETWEEN",
- /* 214 */ "between_op ::= NOT BETWEEN",
- /* 215 */ "expr ::= expr between_op expr AND expr",
- /* 216 */ "in_op ::= IN",
- /* 217 */ "in_op ::= NOT IN",
- /* 218 */ "expr ::= expr in_op LP exprlist RP",
- /* 219 */ "expr ::= LP select RP",
- /* 220 */ "expr ::= expr in_op LP select RP",
- /* 221 */ "expr ::= expr in_op nm dbnm",
- /* 222 */ "expr ::= EXISTS LP select RP",
- /* 223 */ "expr ::= CASE case_operand case_exprlist case_else END",
- /* 224 */ "case_exprlist ::= case_exprlist WHEN expr THEN expr",
- /* 225 */ "case_exprlist ::= WHEN expr THEN expr",
- /* 226 */ "case_else ::= ELSE expr",
- /* 227 */ "case_else ::=",
- /* 228 */ "case_operand ::= expr",
- /* 229 */ "case_operand ::=",
- /* 230 */ "exprlist ::= nexprlist",
- /* 231 */ "exprlist ::=",
- /* 232 */ "nexprlist ::= nexprlist COMMA expr",
- /* 233 */ "nexprlist ::= expr",
- /* 234 */ "cmd ::= CREATE uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP",
- /* 235 */ "uniqueflag ::= UNIQUE",
- /* 236 */ "uniqueflag ::=",
- /* 237 */ "idxlist_opt ::=",
- /* 238 */ "idxlist_opt ::= LP idxlist RP",
- /* 239 */ "idxlist ::= idxlist COMMA idxitem collate sortorder",
- /* 240 */ "idxlist ::= idxitem collate sortorder",
- /* 241 */ "idxitem ::= nm",
- /* 242 */ "collate ::=",
- /* 243 */ "collate ::= COLLATE ids",
- /* 244 */ "cmd ::= DROP INDEX ifexists fullname",
- /* 245 */ "cmd ::= VACUUM",
- /* 246 */ "cmd ::= VACUUM nm",
- /* 247 */ "cmd ::= PRAGMA nm dbnm EQ nmnum",
- /* 248 */ "cmd ::= PRAGMA nm dbnm EQ ON",
- /* 249 */ "cmd ::= PRAGMA nm dbnm EQ minus_num",
- /* 250 */ "cmd ::= PRAGMA nm dbnm LP nmnum RP",
- /* 251 */ "cmd ::= PRAGMA nm dbnm",
- /* 252 */ "nmnum ::= plus_num",
- /* 253 */ "nmnum ::= nm",
- /* 254 */ "plus_num ::= plus_opt number",
- /* 255 */ "minus_num ::= MINUS number",
- /* 256 */ "number ::= INTEGER|FLOAT",
- /* 257 */ "plus_opt ::= PLUS",
- /* 258 */ "plus_opt ::=",
- /* 259 */ "cmd ::= CREATE trigger_decl BEGIN trigger_cmd_list END",
- /* 260 */ "trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause",
- /* 261 */ "trigger_time ::= BEFORE",
- /* 262 */ "trigger_time ::= AFTER",
- /* 263 */ "trigger_time ::= INSTEAD OF",
- /* 264 */ "trigger_time ::=",
- /* 265 */ "trigger_event ::= DELETE|INSERT",
- /* 266 */ "trigger_event ::= UPDATE",
- /* 267 */ "trigger_event ::= UPDATE OF inscollist",
- /* 268 */ "foreach_clause ::=",
- /* 269 */ "foreach_clause ::= FOR EACH ROW",
- /* 270 */ "when_clause ::=",
- /* 271 */ "when_clause ::= WHEN expr",
- /* 272 */ "trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI",
- /* 273 */ "trigger_cmd_list ::=",
- /* 274 */ "trigger_cmd ::= UPDATE orconf nm SET setlist where_opt",
- /* 275 */ "trigger_cmd ::= insert_cmd INTO nm inscollist_opt VALUES LP itemlist RP",
- /* 276 */ "trigger_cmd ::= insert_cmd INTO nm inscollist_opt select",
- /* 277 */ "trigger_cmd ::= DELETE FROM nm where_opt",
- /* 278 */ "trigger_cmd ::= select",
- /* 279 */ "expr ::= RAISE LP IGNORE RP",
- /* 280 */ "expr ::= RAISE LP raisetype COMMA nm RP",
- /* 281 */ "raisetype ::= ROLLBACK",
- /* 282 */ "raisetype ::= ABORT",
- /* 283 */ "raisetype ::= FAIL",
- /* 284 */ "cmd ::= DROP TRIGGER ifexists fullname",
- /* 285 */ "cmd ::= ATTACH database_kw_opt expr AS expr key_opt",
- /* 286 */ "cmd ::= DETACH database_kw_opt expr",
- /* 287 */ "key_opt ::=",
- /* 288 */ "key_opt ::= KEY expr",
- /* 289 */ "database_kw_opt ::= DATABASE",
- /* 290 */ "database_kw_opt ::=",
- /* 291 */ "cmd ::= REINDEX",
- /* 292 */ "cmd ::= REINDEX nm dbnm",
- /* 293 */ "cmd ::= ANALYZE",
- /* 294 */ "cmd ::= ANALYZE nm dbnm",
- /* 295 */ "cmd ::= ALTER TABLE fullname RENAME TO nm",
- /* 296 */ "cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column",
- /* 297 */ "add_column_fullname ::= fullname",
- /* 298 */ "kwcolumn_opt ::=",
- /* 299 */ "kwcolumn_opt ::= COLUMNKW",
- /* 300 */ "cmd ::= create_vtab",
- /* 301 */ "cmd ::= create_vtab LP vtabarglist RP",
- /* 302 */ "create_vtab ::= CREATE VIRTUAL TABLE nm dbnm USING nm",
- /* 303 */ "vtabarglist ::= vtabarg",
- /* 304 */ "vtabarglist ::= vtabarglist COMMA vtabarg",
- /* 305 */ "vtabarg ::=",
- /* 306 */ "vtabarg ::= vtabarg vtabargtoken",
- /* 307 */ "vtabargtoken ::= ANY",
- /* 308 */ "vtabargtoken ::= lp anylist RP",
- /* 309 */ "lp ::= LP",
- /* 310 */ "anylist ::=",
- /* 311 */ "anylist ::= anylist ANY",
+ /* 139 */ "indexed_opt ::=",
+ /* 140 */ "indexed_opt ::= INDEXED BY nm",
+ /* 141 */ "indexed_opt ::= NOT INDEXED",
+ /* 142 */ "using_opt ::= USING LP inscollist RP",
+ /* 143 */ "using_opt ::=",
+ /* 144 */ "orderby_opt ::=",
+ /* 145 */ "orderby_opt ::= ORDER BY sortlist",
+ /* 146 */ "sortlist ::= sortlist COMMA sortitem sortorder",
+ /* 147 */ "sortlist ::= sortitem sortorder",
+ /* 148 */ "sortitem ::= expr",
+ /* 149 */ "sortorder ::= ASC",
+ /* 150 */ "sortorder ::= DESC",
+ /* 151 */ "sortorder ::=",
+ /* 152 */ "groupby_opt ::=",
+ /* 153 */ "groupby_opt ::= GROUP BY nexprlist",
+ /* 154 */ "having_opt ::=",
+ /* 155 */ "having_opt ::= HAVING expr",
+ /* 156 */ "limit_opt ::=",
+ /* 157 */ "limit_opt ::= LIMIT expr",
+ /* 158 */ "limit_opt ::= LIMIT expr OFFSET expr",
+ /* 159 */ "limit_opt ::= LIMIT expr COMMA expr",
+ /* 160 */ "cmd ::= DELETE FROM fullname indexed_opt where_opt",
+ /* 161 */ "where_opt ::=",
+ /* 162 */ "where_opt ::= WHERE expr",
+ /* 163 */ "cmd ::= UPDATE orconf fullname indexed_opt SET setlist where_opt",
+ /* 164 */ "setlist ::= setlist COMMA nm EQ expr",
+ /* 165 */ "setlist ::= nm EQ expr",
+ /* 166 */ "cmd ::= insert_cmd INTO fullname inscollist_opt VALUES LP itemlist RP",
+ /* 167 */ "cmd ::= insert_cmd INTO fullname inscollist_opt select",
+ /* 168 */ "cmd ::= insert_cmd INTO fullname inscollist_opt DEFAULT VALUES",
+ /* 169 */ "insert_cmd ::= INSERT orconf",
+ /* 170 */ "insert_cmd ::= REPLACE",
+ /* 171 */ "itemlist ::= itemlist COMMA expr",
+ /* 172 */ "itemlist ::= expr",
+ /* 173 */ "inscollist_opt ::=",
+ /* 174 */ "inscollist_opt ::= LP inscollist RP",
+ /* 175 */ "inscollist ::= inscollist COMMA nm",
+ /* 176 */ "inscollist ::= nm",
+ /* 177 */ "expr ::= term",
+ /* 178 */ "expr ::= LP expr RP",
+ /* 179 */ "term ::= NULL",
+ /* 180 */ "expr ::= ID",
+ /* 181 */ "expr ::= JOIN_KW",
+ /* 182 */ "expr ::= nm DOT nm",
+ /* 183 */ "expr ::= nm DOT nm DOT nm",
+ /* 184 */ "term ::= INTEGER|FLOAT|BLOB",
+ /* 185 */ "term ::= STRING",
+ /* 186 */ "expr ::= REGISTER",
+ /* 187 */ "expr ::= VARIABLE",
+ /* 188 */ "expr ::= expr COLLATE ids",
+ /* 189 */ "expr ::= CAST LP expr AS typetoken RP",
+ /* 190 */ "expr ::= ID LP distinct exprlist RP",
+ /* 191 */ "expr ::= ID LP STAR RP",
+ /* 192 */ "term ::= CTIME_KW",
+ /* 193 */ "expr ::= expr AND expr",
+ /* 194 */ "expr ::= expr OR expr",
+ /* 195 */ "expr ::= expr LT|GT|GE|LE expr",
+ /* 196 */ "expr ::= expr EQ|NE expr",
+ /* 197 */ "expr ::= expr BITAND|BITOR|LSHIFT|RSHIFT expr",
+ /* 198 */ "expr ::= expr PLUS|MINUS expr",
+ /* 199 */ "expr ::= expr STAR|SLASH|REM expr",
+ /* 200 */ "expr ::= expr CONCAT expr",
+ /* 201 */ "likeop ::= LIKE_KW",
+ /* 202 */ "likeop ::= NOT LIKE_KW",
+ /* 203 */ "likeop ::= MATCH",
+ /* 204 */ "likeop ::= NOT MATCH",
+ /* 205 */ "escape ::= ESCAPE expr",
+ /* 206 */ "escape ::=",
+ /* 207 */ "expr ::= expr likeop expr escape",
+ /* 208 */ "expr ::= expr ISNULL|NOTNULL",
+ /* 209 */ "expr ::= expr IS NULL",
+ /* 210 */ "expr ::= expr NOT NULL",
+ /* 211 */ "expr ::= expr IS NOT NULL",
+ /* 212 */ "expr ::= NOT expr",
+ /* 213 */ "expr ::= BITNOT expr",
+ /* 214 */ "expr ::= MINUS expr",
+ /* 215 */ "expr ::= PLUS expr",
+ /* 216 */ "between_op ::= BETWEEN",
+ /* 217 */ "between_op ::= NOT BETWEEN",
+ /* 218 */ "expr ::= expr between_op expr AND expr",
+ /* 219 */ "in_op ::= IN",
+ /* 220 */ "in_op ::= NOT IN",
+ /* 221 */ "expr ::= expr in_op LP exprlist RP",
+ /* 222 */ "expr ::= LP select RP",
+ /* 223 */ "expr ::= expr in_op LP select RP",
+ /* 224 */ "expr ::= expr in_op nm dbnm",
+ /* 225 */ "expr ::= EXISTS LP select RP",
+ /* 226 */ "expr ::= CASE case_operand case_exprlist case_else END",
+ /* 227 */ "case_exprlist ::= case_exprlist WHEN expr THEN expr",
+ /* 228 */ "case_exprlist ::= WHEN expr THEN expr",
+ /* 229 */ "case_else ::= ELSE expr",
+ /* 230 */ "case_else ::=",
+ /* 231 */ "case_operand ::= expr",
+ /* 232 */ "case_operand ::=",
+ /* 233 */ "exprlist ::= nexprlist",
+ /* 234 */ "exprlist ::=",
+ /* 235 */ "nexprlist ::= nexprlist COMMA expr",
+ /* 236 */ "nexprlist ::= expr",
+ /* 237 */ "cmd ::= CREATE uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP",
+ /* 238 */ "uniqueflag ::= UNIQUE",
+ /* 239 */ "uniqueflag ::=",
+ /* 240 */ "idxlist_opt ::=",
+ /* 241 */ "idxlist_opt ::= LP idxlist RP",
+ /* 242 */ "idxlist ::= idxlist COMMA nm collate sortorder",
+ /* 243 */ "idxlist ::= nm collate sortorder",
+ /* 244 */ "collate ::=",
+ /* 245 */ "collate ::= COLLATE ids",
+ /* 246 */ "cmd ::= DROP INDEX ifexists fullname",
+ /* 247 */ "cmd ::= VACUUM",
+ /* 248 */ "cmd ::= VACUUM nm",
+ /* 249 */ "cmd ::= PRAGMA nm dbnm EQ nmnum",
+ /* 250 */ "cmd ::= PRAGMA nm dbnm EQ ON",
+ /* 251 */ "cmd ::= PRAGMA nm dbnm EQ DELETE",
+ /* 252 */ "cmd ::= PRAGMA nm dbnm EQ minus_num",
+ /* 253 */ "cmd ::= PRAGMA nm dbnm LP nmnum RP",
+ /* 254 */ "cmd ::= PRAGMA nm dbnm",
+ /* 255 */ "nmnum ::= plus_num",
+ /* 256 */ "nmnum ::= nm",
+ /* 257 */ "plus_num ::= plus_opt number",
+ /* 258 */ "minus_num ::= MINUS number",
+ /* 259 */ "number ::= INTEGER|FLOAT",
+ /* 260 */ "plus_opt ::= PLUS",
+ /* 261 */ "plus_opt ::=",
+ /* 262 */ "cmd ::= CREATE trigger_decl BEGIN trigger_cmd_list END",
+ /* 263 */ "trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause",
+ /* 264 */ "trigger_time ::= BEFORE",
+ /* 265 */ "trigger_time ::= AFTER",
+ /* 266 */ "trigger_time ::= INSTEAD OF",
+ /* 267 */ "trigger_time ::=",
+ /* 268 */ "trigger_event ::= DELETE|INSERT",
+ /* 269 */ "trigger_event ::= UPDATE",
+ /* 270 */ "trigger_event ::= UPDATE OF inscollist",
+ /* 271 */ "foreach_clause ::=",
+ /* 272 */ "foreach_clause ::= FOR EACH ROW",
+ /* 273 */ "when_clause ::=",
+ /* 274 */ "when_clause ::= WHEN expr",
+ /* 275 */ "trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI",
+ /* 276 */ "trigger_cmd_list ::= trigger_cmd SEMI",
+ /* 277 */ "trigger_cmd ::= UPDATE orconf nm SET setlist where_opt",
+ /* 278 */ "trigger_cmd ::= insert_cmd INTO nm inscollist_opt VALUES LP itemlist RP",
+ /* 279 */ "trigger_cmd ::= insert_cmd INTO nm inscollist_opt select",
+ /* 280 */ "trigger_cmd ::= DELETE FROM nm where_opt",
+ /* 281 */ "trigger_cmd ::= select",
+ /* 282 */ "expr ::= RAISE LP IGNORE RP",
+ /* 283 */ "expr ::= RAISE LP raisetype COMMA nm RP",
+ /* 284 */ "raisetype ::= ROLLBACK",
+ /* 285 */ "raisetype ::= ABORT",
+ /* 286 */ "raisetype ::= FAIL",
+ /* 287 */ "cmd ::= DROP TRIGGER ifexists fullname",
+ /* 288 */ "cmd ::= ATTACH database_kw_opt expr AS expr key_opt",
+ /* 289 */ "cmd ::= DETACH database_kw_opt expr",
+ /* 290 */ "key_opt ::=",
+ /* 291 */ "key_opt ::= KEY expr",
+ /* 292 */ "database_kw_opt ::= DATABASE",
+ /* 293 */ "database_kw_opt ::=",
+ /* 294 */ "cmd ::= REINDEX",
+ /* 295 */ "cmd ::= REINDEX nm dbnm",
+ /* 296 */ "cmd ::= ANALYZE",
+ /* 297 */ "cmd ::= ANALYZE nm dbnm",
+ /* 298 */ "cmd ::= ALTER TABLE fullname RENAME TO nm",
+ /* 299 */ "cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column",
+ /* 300 */ "add_column_fullname ::= fullname",
+ /* 301 */ "kwcolumn_opt ::=",
+ /* 302 */ "kwcolumn_opt ::= COLUMNKW",
+ /* 303 */ "cmd ::= create_vtab",
+ /* 304 */ "cmd ::= create_vtab LP vtabarglist RP",
+ /* 305 */ "create_vtab ::= CREATE VIRTUAL TABLE nm dbnm USING nm",
+ /* 306 */ "vtabarglist ::= vtabarg",
+ /* 307 */ "vtabarglist ::= vtabarglist COMMA vtabarg",
+ /* 308 */ "vtabarg ::=",
+ /* 309 */ "vtabarg ::= vtabarg vtabargtoken",
+ /* 310 */ "vtabargtoken ::= ANY",
+ /* 311 */ "vtabargtoken ::= lp anylist RP",
+ /* 312 */ "lp ::= LP",
+ /* 313 */ "anylist ::=",
+ /* 314 */ "anylist ::= anylist ANY",
 };
 #endif /* NDEBUG */
 
@@ -71974,6 +80068,9 @@ SQLITE_PRIVATE void *sqlite3ParserAlloc(void *(*mallocProc)(size_t)){
   pParser = (yyParser*)(*mallocProc)( (size_t)sizeof(yyParser) );
   if( pParser ){
     pParser->yyidx = -1;
+#ifdef YYTRACKMAXSTACKDEPTH
+    pParser->yyidxMax = 0;
+#endif
 #if YYSTACKDEPTH<=0
     yyGrowStack(pParser);
 #endif
@@ -71986,7 +80083,12 @@ SQLITE_PRIVATE void *sqlite3ParserAlloc(void *(*mallocProc)(size_t)){
 ** "yymajor" is the symbol code, and "yypminor" is a pointer to
 ** the value.
 */
-static void yy_destructor(YYCODETYPE yymajor, YYMINORTYPE *yypminor){
+static void yy_destructor(
+  yyParser *yypParser,    /* The parser */
+  YYCODETYPE yymajor,     /* Type code for object to destroy */
+  YYMINORTYPE *yypminor   /* The object to be destroyed */
+){
+  sqlite3ParserARG_FETCH;
   switch( yymajor ){
     /* Here is inserted the actions which take place when a
     ** terminal or non-terminal is destroyed.  This can happen
@@ -71998,55 +80100,69 @@ static void yy_destructor(YYCODETYPE yymajor, YYMINORTYPE *yypminor){
     ** which appear on the RHS of the rule, but which are not used
     ** inside the C code.
     */
-    case 155: /* select */
-    case 189: /* oneselect */
-    case 206: /* seltablist_paren */
-{sqlite3SelectDelete((yypminor->yy219));}
+    case 156: /* select */
+    case 190: /* oneselect */
+    case 208: /* seltablist_paren */
+{
+sqlite3SelectDelete(pParse->db, (yypminor->yy43));
+}
       break;
-    case 169: /* term */
-    case 170: /* expr */
-    case 194: /* where_opt */
-    case 196: /* having_opt */
-    case 204: /* on_opt */
-    case 210: /* sortitem */
-    case 218: /* escape */
-    case 221: /* case_operand */
-    case 223: /* case_else */
-    case 235: /* when_clause */
-    case 238: /* key_opt */
-{sqlite3ExprDelete((yypminor->yy172));}
+    case 170: /* term */
+    case 171: /* expr */
+    case 195: /* where_opt */
+    case 197: /* having_opt */
+    case 206: /* on_opt */
+    case 212: /* sortitem */
+    case 220: /* escape */
+    case 223: /* case_operand */
+    case 225: /* case_else */
+    case 236: /* when_clause */
+    case 239: /* key_opt */
+{
+sqlite3ExprDelete(pParse->db, (yypminor->yy450));
+}
       break;
-    case 174: /* idxlist_opt */
-    case 182: /* idxlist */
-    case 192: /* selcollist */
-    case 195: /* groupby_opt */
-    case 197: /* orderby_opt */
-    case 199: /* sclp */
-    case 209: /* sortlist */
-    case 211: /* nexprlist */
-    case 212: /* setlist */
-    case 215: /* itemlist */
-    case 216: /* exprlist */
-    case 222: /* case_exprlist */
-{sqlite3ExprListDelete((yypminor->yy174));}
+    case 175: /* idxlist_opt */
+    case 183: /* idxlist */
+    case 193: /* selcollist */
+    case 196: /* groupby_opt */
+    case 198: /* orderby_opt */
+    case 200: /* sclp */
+    case 211: /* sortlist */
+    case 213: /* nexprlist */
+    case 214: /* setlist */
+    case 217: /* itemlist */
+    case 218: /* exprlist */
+    case 224: /* case_exprlist */
+{
+sqlite3ExprListDelete(pParse->db, (yypminor->yy242));
+}
       break;
-    case 188: /* fullname */
-    case 193: /* from */
-    case 201: /* seltablist */
-    case 202: /* stl_prefix */
-{sqlite3SrcListDelete((yypminor->yy373));}
+    case 189: /* fullname */
+    case 194: /* from */
+    case 202: /* seltablist */
+    case 203: /* stl_prefix */
+{
+sqlite3SrcListDelete(pParse->db, (yypminor->yy419));
+}
       break;
-    case 205: /* using_opt */
-    case 208: /* inscollist */
-    case 214: /* inscollist_opt */
-{sqlite3IdListDelete((yypminor->yy432));}
+    case 207: /* using_opt */
+    case 210: /* inscollist */
+    case 216: /* inscollist_opt */
+{
+sqlite3IdListDelete(pParse->db, (yypminor->yy352));
+}
       break;
-    case 231: /* trigger_cmd_list */
-    case 236: /* trigger_cmd */
-{sqlite3DeleteTriggerStep((yypminor->yy243));}
+    case 232: /* trigger_cmd_list */
+    case 237: /* trigger_cmd */
+{
+sqlite3DeleteTriggerStep(pParse->db, (yypminor->yy75));
+}
       break;
-    case 233: /* trigger_event */
-{sqlite3IdListDelete((yypminor->yy370).b);}
+    case 234: /* trigger_event */
+{
+sqlite3IdListDelete(pParse->db, (yypminor->yy354).b);
+}
       break;
     default:  break;   /* If no destructor action specified: do nothing */
   }
@@ -72073,7 +80189,7 @@ static int yy_pop_parser_stack(yyParser *pParser){
   }
 #endif
   yymajor = yytos->major;
-  yy_destructor( yymajor, &yytos->minor);
+  yy_destructor(pParser, yymajor, &yytos->minor);
   pParser->yyidx--;
   return yymajor;
 }
@@ -72104,6 +80220,16 @@ SQLITE_PRIVATE void sqlite3ParserFree(
 }
 
 /*
+** Return the peak depth of the stack for a parser.
+*/
+#ifdef YYTRACKMAXSTACKDEPTH
+SQLITE_PRIVATE int sqlite3ParserStackPeak(void *p){
+  yyParser *pParser = (yyParser*)p;
+  return pParser->yyidxMax;
+}
+#endif
+
+/*
 ** Find the appropriate action for a parser given the terminal
 ** look-ahead token iLookAhead.
 **
@@ -72172,13 +80298,25 @@ static int yy_find_reduce_action(
   YYCODETYPE iLookAhead     /* The look-ahead token */
 ){
   int i;
+#ifdef YYERRORSYMBOL
+  if( stateno>YY_REDUCE_MAX ){
+    return yy_default[stateno];
+  }
+#else
   assert( stateno<=YY_REDUCE_MAX );
+#endif
   i = yy_reduce_ofst[stateno];
   assert( i!=YY_REDUCE_USE_DFLT );
   assert( iLookAhead!=YYNOCODE );
   i += iLookAhead;
+#ifdef YYERRORSYMBOL
+  if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
+    return yy_default[stateno];
+  }
+#else
   assert( i>=0 && iyyidx++;
+#ifdef YYTRACKMAXSTACKDEPTH
+  if( yypParser->yyidx>yypParser->yyidxMax ){
+    yypParser->yyidxMax = yypParser->yyidx;
+  }
+#endif
 #if YYSTACKDEPTH>0 
   if( yypParser->yyidx>=YYSTACKDEPTH ){
     yyStackOverflow(yypParser, yypMinor);
@@ -72250,318 +80393,321 @@ static const struct {
   YYCODETYPE lhs;         /* Symbol on the left-hand side of the rule */
   unsigned char nrhs;     /* Number of right-hand side symbols in the rule */
 } yyRuleInfo[] = {
-  { 139, 1 },
-  { 140, 2 },
   { 140, 1 },
-  { 142, 1 },
+  { 141, 2 },
   { 141, 1 },
-  { 141, 3 },
-  { 144, 0 },
-  { 144, 1 },
-  { 144, 3 },
+  { 142, 1 },
+  { 142, 3 },
+  { 143, 0 },
+  { 143, 1 },
   { 143, 3 },
+  { 144, 1 },
+  { 145, 3 },
+  { 147, 0 },
+  { 147, 1 },
+  { 147, 2 },
   { 146, 0 },
   { 146, 1 },
-  { 146, 2 },
-  { 145, 0 },
-  { 145, 1 },
-  { 145, 1 },
-  { 145, 1 },
-  { 143, 2 },
-  { 143, 2 },
-  { 143, 2 },
-  { 143, 2 },
-  { 148, 6 },
+  { 146, 1 },
+  { 146, 1 },
+  { 145, 2 },
+  { 145, 2 },
+  { 145, 2 },
+  { 145, 2 },
+  { 149, 6 },
+  { 152, 0 },
+  { 152, 3 },
+  { 151, 1 },
   { 151, 0 },
-  { 151, 3 },
-  { 150, 1 },
-  { 150, 0 },
-  { 149, 4 },
-  { 149, 2 },
-  { 153, 3 },
-  { 153, 1 },
-  { 156, 3 },
-  { 157, 1 },
-  { 160, 1 },
-  { 161, 1 },
-  { 147, 1 },
-  { 147, 1 },
-  { 147, 1 },
-  { 158, 0 },
+  { 150, 4 },
+  { 150, 2 },
+  { 154, 3 },
+  { 154, 1 },
+  { 157, 3 },
   { 158, 1 },
+  { 161, 1 },
   { 162, 1 },
-  { 162, 4 },
-  { 162, 6 },
+  { 148, 1 },
+  { 148, 1 },
+  { 148, 1 },
+  { 159, 0 },
+  { 159, 1 },
   { 163, 1 },
-  { 163, 2 },
+  { 163, 4 },
+  { 163, 6 },
   { 164, 1 },
-  { 164, 1 },
-  { 159, 2 },
-  { 159, 0 },
-  { 167, 3 },
-  { 167, 1 },
-  { 168, 2 },
-  { 168, 4 },
-  { 168, 3 },
+  { 164, 2 },
+  { 165, 1 },
+  { 165, 1 },
+  { 160, 2 },
+  { 160, 0 },
   { 168, 3 },
-  { 168, 2 },
-  { 168, 2 },
-  { 168, 3 },
-  { 168, 5 },
-  { 168, 2 },
-  { 168, 4 },
-  { 168, 4 },
   { 168, 1 },
-  { 168, 2 },
-  { 173, 0 },
-  { 173, 1 },
-  { 175, 0 },
-  { 175, 2 },
-  { 177, 2 },
-  { 177, 3 },
-  { 177, 3 },
-  { 177, 3 },
-  { 178, 2 },
-  { 178, 2 },
-  { 178, 1 },
-  { 178, 1 },
-  { 176, 3 },
+  { 169, 2 },
+  { 169, 4 },
+  { 169, 3 },
+  { 169, 3 },
+  { 169, 2 },
+  { 169, 2 },
+  { 169, 3 },
+  { 169, 5 },
+  { 169, 2 },
+  { 169, 4 },
+  { 169, 4 },
+  { 169, 1 },
+  { 169, 2 },
+  { 174, 0 },
+  { 174, 1 },
+  { 176, 0 },
   { 176, 2 },
-  { 179, 0 },
+  { 178, 2 },
+  { 178, 3 },
+  { 178, 3 },
+  { 178, 3 },
   { 179, 2 },
   { 179, 2 },
-  { 154, 0 },
-  { 154, 2 },
-  { 180, 3 },
+  { 179, 1 },
+  { 179, 1 },
+  { 177, 3 },
+  { 177, 2 },
+  { 180, 0 },
   { 180, 2 },
-  { 180, 1 },
+  { 180, 2 },
+  { 155, 0 },
+  { 155, 2 },
+  { 181, 3 },
   { 181, 2 },
-  { 181, 7 },
-  { 181, 5 },
-  { 181, 5 },
-  { 181, 10 },
-  { 183, 0 },
-  { 183, 1 },
-  { 171, 0 },
-  { 171, 3 },
+  { 181, 1 },
+  { 182, 2 },
+  { 182, 7 },
+  { 182, 5 },
+  { 182, 5 },
+  { 182, 10 },
   { 184, 0 },
-  { 184, 2 },
-  { 185, 1 },
-  { 185, 1 },
-  { 185, 1 },
-  { 143, 4 },
-  { 187, 2 },
-  { 187, 0 },
-  { 143, 8 },
-  { 143, 4 },
-  { 143, 1 },
-  { 155, 1 },
-  { 155, 3 },
-  { 190, 1 },
-  { 190, 2 },
-  { 190, 1 },
-  { 189, 9 },
+  { 184, 1 },
+  { 172, 0 },
+  { 172, 3 },
+  { 185, 0 },
+  { 185, 2 },
+  { 186, 1 },
+  { 186, 1 },
+  { 186, 1 },
+  { 145, 4 },
+  { 188, 2 },
+  { 188, 0 },
+  { 145, 8 },
+  { 145, 4 },
+  { 145, 1 },
+  { 156, 1 },
+  { 156, 3 },
   { 191, 1 },
+  { 191, 2 },
   { 191, 1 },
-  { 191, 0 },
-  { 199, 2 },
-  { 199, 0 },
-  { 192, 3 },
-  { 192, 2 },
-  { 192, 4 },
+  { 190, 9 },
+  { 192, 1 },
+  { 192, 1 },
+  { 192, 0 },
   { 200, 2 },
-  { 200, 1 },
   { 200, 0 },
-  { 193, 0 },
+  { 193, 3 },
   { 193, 2 },
-  { 202, 2 },
-  { 202, 0 },
-  { 201, 6 },
-  { 201, 7 },
-  { 206, 1 },
-  { 206, 1 },
-  { 152, 0 },
-  { 152, 2 },
-  { 188, 2 },
-  { 203, 1 },
+  { 193, 4 },
+  { 201, 2 },
+  { 201, 1 },
+  { 201, 0 },
+  { 194, 0 },
+  { 194, 2 },
   { 203, 2 },
-  { 203, 3 },
-  { 203, 4 },
+  { 203, 0 },
+  { 202, 7 },
+  { 202, 7 },
+  { 208, 1 },
+  { 208, 1 },
+  { 153, 0 },
+  { 153, 2 },
+  { 189, 2 },
+  { 204, 1 },
   { 204, 2 },
-  { 204, 0 },
-  { 205, 4 },
+  { 204, 3 },
+  { 204, 4 },
+  { 206, 2 },
+  { 206, 0 },
   { 205, 0 },
+  { 205, 3 },
+  { 205, 2 },
+  { 207, 4 },
+  { 207, 0 },
+  { 198, 0 },
+  { 198, 3 },
+  { 211, 4 },
+  { 211, 2 },
+  { 212, 1 },
+  { 173, 1 },
+  { 173, 1 },
+  { 173, 0 },
+  { 196, 0 },
+  { 196, 3 },
   { 197, 0 },
-  { 197, 3 },
-  { 209, 4 },
-  { 209, 2 },
-  { 210, 1 },
-  { 172, 1 },
-  { 172, 1 },
-  { 172, 0 },
+  { 197, 2 },
+  { 199, 0 },
+  { 199, 2 },
+  { 199, 4 },
+  { 199, 4 },
+  { 145, 5 },
   { 195, 0 },
-  { 195, 3 },
-  { 196, 0 },
-  { 196, 2 },
-  { 198, 0 },
-  { 198, 2 },
-  { 198, 4 },
-  { 198, 4 },
-  { 143, 4 },
-  { 194, 0 },
-  { 194, 2 },
-  { 143, 6 },
-  { 212, 5 },
-  { 212, 3 },
-  { 143, 8 },
-  { 143, 5 },
-  { 143, 6 },
-  { 213, 2 },
-  { 213, 1 },
-  { 215, 3 },
-  { 215, 1 },
-  { 214, 0 },
+  { 195, 2 },
+  { 145, 7 },
+  { 214, 5 },
   { 214, 3 },
-  { 208, 3 },
-  { 208, 1 },
-  { 170, 1 },
-  { 170, 3 },
-  { 169, 1 },
+  { 145, 8 },
+  { 145, 5 },
+  { 145, 6 },
+  { 215, 2 },
+  { 215, 1 },
+  { 217, 3 },
+  { 217, 1 },
+  { 216, 0 },
+  { 216, 3 },
+  { 210, 3 },
+  { 210, 1 },
+  { 171, 1 },
+  { 171, 3 },
   { 170, 1 },
+  { 171, 1 },
+  { 171, 1 },
+  { 171, 3 },
+  { 171, 5 },
   { 170, 1 },
-  { 170, 3 },
-  { 170, 5 },
-  { 169, 1 },
-  { 169, 1 },
   { 170, 1 },
+  { 171, 1 },
+  { 171, 1 },
+  { 171, 3 },
+  { 171, 6 },
+  { 171, 5 },
+  { 171, 4 },
   { 170, 1 },
-  { 170, 3 },
-  { 170, 6 },
-  { 170, 5 },
-  { 170, 4 },
-  { 169, 1 },
-  { 170, 3 },
-  { 170, 3 },
-  { 170, 3 },
-  { 170, 3 },
-  { 170, 3 },
-  { 170, 3 },
-  { 170, 3 },
-  { 170, 3 },
-  { 217, 1 },
-  { 217, 2 },
-  { 217, 1 },
-  { 217, 2 },
-  { 218, 2 },
-  { 218, 0 },
-  { 170, 4 },
-  { 170, 2 },
-  { 170, 3 },
-  { 170, 3 },
-  { 170, 4 },
-  { 170, 2 },
-  { 170, 2 },
-  { 170, 2 },
-  { 170, 2 },
+  { 171, 3 },
+  { 171, 3 },
+  { 171, 3 },
+  { 171, 3 },
+  { 171, 3 },
+  { 171, 3 },
+  { 171, 3 },
+  { 171, 3 },
+  { 219, 1 },
+  { 219, 2 },
   { 219, 1 },
   { 219, 2 },
-  { 170, 5 },
-  { 220, 1 },
   { 220, 2 },
-  { 170, 5 },
-  { 170, 3 },
-  { 170, 5 },
-  { 170, 4 },
-  { 170, 4 },
-  { 170, 5 },
-  { 222, 5 },
-  { 222, 4 },
-  { 223, 2 },
-  { 223, 0 },
+  { 220, 0 },
+  { 171, 4 },
+  { 171, 2 },
+  { 171, 3 },
+  { 171, 3 },
+  { 171, 4 },
+  { 171, 2 },
+  { 171, 2 },
+  { 171, 2 },
+  { 171, 2 },
   { 221, 1 },
-  { 221, 0 },
-  { 216, 1 },
-  { 216, 0 },
-  { 211, 3 },
-  { 211, 1 },
-  { 143, 11 },
-  { 224, 1 },
-  { 224, 0 },
-  { 174, 0 },
-  { 174, 3 },
-  { 182, 5 },
-  { 182, 3 },
-  { 225, 1 },
+  { 221, 2 },
+  { 171, 5 },
+  { 222, 1 },
+  { 222, 2 },
+  { 171, 5 },
+  { 171, 3 },
+  { 171, 5 },
+  { 171, 4 },
+  { 171, 4 },
+  { 171, 5 },
+  { 224, 5 },
+  { 224, 4 },
+  { 225, 2 },
+  { 225, 0 },
+  { 223, 1 },
+  { 223, 0 },
+  { 218, 1 },
+  { 218, 0 },
+  { 213, 3 },
+  { 213, 1 },
+  { 145, 11 },
+  { 226, 1 },
   { 226, 0 },
-  { 226, 2 },
-  { 143, 4 },
-  { 143, 1 },
-  { 143, 2 },
-  { 143, 5 },
-  { 143, 5 },
-  { 143, 5 },
-  { 143, 6 },
-  { 143, 3 },
-  { 227, 1 },
-  { 227, 1 },
-  { 165, 2 },
+  { 175, 0 },
+  { 175, 3 },
+  { 183, 5 },
+  { 183, 3 },
+  { 227, 0 },
+  { 227, 2 },
+  { 145, 4 },
+  { 145, 1 },
+  { 145, 2 },
+  { 145, 5 },
+  { 145, 5 },
+  { 145, 5 },
+  { 145, 5 },
+  { 145, 6 },
+  { 145, 3 },
+  { 228, 1 },
+  { 228, 1 },
   { 166, 2 },
+  { 167, 2 },
+  { 230, 1 },
   { 229, 1 },
-  { 228, 1 },
-  { 228, 0 },
-  { 143, 5 },
-  { 230, 11 },
-  { 232, 1 },
-  { 232, 1 },
-  { 232, 2 },
-  { 232, 0 },
+  { 229, 0 },
+  { 145, 5 },
+  { 231, 11 },
   { 233, 1 },
   { 233, 1 },
-  { 233, 3 },
-  { 234, 0 },
+  { 233, 2 },
+  { 233, 0 },
+  { 234, 1 },
+  { 234, 1 },
   { 234, 3 },
   { 235, 0 },
-  { 235, 2 },
-  { 231, 3 },
-  { 231, 0 },
-  { 236, 6 },
-  { 236, 8 },
-  { 236, 5 },
-  { 236, 4 },
-  { 236, 1 },
-  { 170, 4 },
-  { 170, 6 },
-  { 186, 1 },
-  { 186, 1 },
-  { 186, 1 },
-  { 143, 4 },
-  { 143, 6 },
-  { 143, 3 },
-  { 238, 0 },
-  { 238, 2 },
+  { 235, 3 },
+  { 236, 0 },
+  { 236, 2 },
+  { 232, 3 },
+  { 232, 2 },
+  { 237, 6 },
+  { 237, 8 },
+  { 237, 5 },
+  { 237, 4 },
   { 237, 1 },
-  { 237, 0 },
-  { 143, 1 },
-  { 143, 3 },
-  { 143, 1 },
-  { 143, 3 },
-  { 143, 6 },
-  { 143, 6 },
-  { 239, 1 },
-  { 240, 0 },
+  { 171, 4 },
+  { 171, 6 },
+  { 187, 1 },
+  { 187, 1 },
+  { 187, 1 },
+  { 145, 4 },
+  { 145, 6 },
+  { 145, 3 },
+  { 239, 0 },
+  { 239, 2 },
+  { 238, 1 },
+  { 238, 0 },
+  { 145, 1 },
+  { 145, 3 },
+  { 145, 1 },
+  { 145, 3 },
+  { 145, 6 },
+  { 145, 6 },
   { 240, 1 },
-  { 143, 1 },
-  { 143, 4 },
-  { 241, 7 },
-  { 242, 1 },
-  { 242, 3 },
-  { 243, 0 },
-  { 243, 2 },
-  { 244, 1 },
-  { 244, 3 },
+  { 241, 0 },
+  { 241, 1 },
+  { 145, 1 },
+  { 145, 4 },
+  { 242, 7 },
+  { 243, 1 },
+  { 243, 3 },
+  { 244, 0 },
+  { 244, 2 },
   { 245, 1 },
-  { 246, 0 },
-  { 246, 2 },
+  { 245, 3 },
+  { 246, 1 },
+  { 247, 0 },
+  { 247, 2 },
 };
 
 static void yy_accept(yyParser*);  /* Forward Declaration */
@@ -72603,7 +80749,8 @@ static void yy_reduce(
   ** from wireshark this week.  Clearly they are stressing Lemon in ways
   ** that it has not been previously stressed...  (SQLite ticket #2172)
   */
-  memset(&yygotominor, 0, sizeof(yygotominor));
+  /*memset(&yygotominor, 0, sizeof(yygotominor));*/
+  yygotominor = yyzerominor;
 
 
   switch( yyruleno ){
@@ -72618,8 +80765,8 @@ static void yy_reduce(
       case 0: /* input ::= cmdlist */
       case 1: /* cmdlist ::= cmdlist ecmd */
       case 2: /* cmdlist ::= ecmd */
-      case 4: /* ecmd ::= SEMI */
-      case 5: /* ecmd ::= explain cmdx SEMI */
+      case 3: /* ecmd ::= SEMI */
+      case 4: /* ecmd ::= explain cmdx SEMI */
       case 10: /* trans_opt ::= */
       case 11: /* trans_opt ::= TRANSACTION */
       case 12: /* trans_opt ::= TRANSACTION nm */
@@ -72638,45 +80785,45 @@ static void yy_reduce(
       case 83: /* conslist ::= conslist tcons */
       case 84: /* conslist ::= tcons */
       case 85: /* tcons ::= CONSTRAINT nm */
-      case 257: /* plus_opt ::= PLUS */
-      case 258: /* plus_opt ::= */
-      case 268: /* foreach_clause ::= */
-      case 269: /* foreach_clause ::= FOR EACH ROW */
-      case 289: /* database_kw_opt ::= DATABASE */
-      case 290: /* database_kw_opt ::= */
-      case 298: /* kwcolumn_opt ::= */
-      case 299: /* kwcolumn_opt ::= COLUMNKW */
-      case 303: /* vtabarglist ::= vtabarg */
-      case 304: /* vtabarglist ::= vtabarglist COMMA vtabarg */
-      case 306: /* vtabarg ::= vtabarg vtabargtoken */
-      case 310: /* anylist ::= */
+      case 260: /* plus_opt ::= PLUS */
+      case 261: /* plus_opt ::= */
+      case 271: /* foreach_clause ::= */
+      case 272: /* foreach_clause ::= FOR EACH ROW */
+      case 292: /* database_kw_opt ::= DATABASE */
+      case 293: /* database_kw_opt ::= */
+      case 301: /* kwcolumn_opt ::= */
+      case 302: /* kwcolumn_opt ::= COLUMNKW */
+      case 306: /* vtabarglist ::= vtabarg */
+      case 307: /* vtabarglist ::= vtabarglist COMMA vtabarg */
+      case 309: /* vtabarg ::= vtabarg vtabargtoken */
+      case 313: /* anylist ::= */
 {
 }
         break;
-      case 3: /* cmdx ::= cmd */
-{ sqlite3FinishCoding(pParse); }
-        break;
-      case 6: /* explain ::= */
+      case 5: /* explain ::= */
 { sqlite3BeginParse(pParse, 0); }
         break;
-      case 7: /* explain ::= EXPLAIN */
+      case 6: /* explain ::= EXPLAIN */
 { sqlite3BeginParse(pParse, 1); }
         break;
-      case 8: /* explain ::= EXPLAIN QUERY PLAN */
+      case 7: /* explain ::= EXPLAIN QUERY PLAN */
 { sqlite3BeginParse(pParse, 2); }
         break;
+      case 8: /* cmdx ::= cmd */
+{ sqlite3FinishCoding(pParse); }
+        break;
       case 9: /* cmd ::= BEGIN transtype trans_opt */
-{sqlite3BeginTransaction(pParse, yymsp[-1].minor.yy46);}
+{sqlite3BeginTransaction(pParse, yymsp[-1].minor.yy316);}
         break;
       case 13: /* transtype ::= */
-{yygotominor.yy46 = TK_DEFERRED;}
+{yygotominor.yy316 = TK_DEFERRED;}
         break;
       case 14: /* transtype ::= DEFERRED */
       case 15: /* transtype ::= IMMEDIATE */
       case 16: /* transtype ::= EXCLUSIVE */
       case 107: /* multiselect_op ::= UNION */
       case 109: /* multiselect_op ::= EXCEPT|INTERSECT */
-{yygotominor.yy46 = yymsp[0].major;}
+{yygotominor.yy316 = yymsp[0].major;}
         break;
       case 17: /* cmd ::= COMMIT trans_opt */
       case 18: /* cmd ::= END trans_opt */
@@ -72687,7 +80834,7 @@ static void yy_reduce(
         break;
       case 21: /* create_table ::= CREATE temp TABLE ifnotexists nm dbnm */
 {
-   sqlite3StartTable(pParse,&yymsp[-1].minor.yy410,&yymsp[0].minor.yy410,yymsp[-4].minor.yy46,0,0,yymsp[-2].minor.yy46);
+   sqlite3StartTable(pParse,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0,yymsp[-4].minor.yy316,0,0,yymsp[-2].minor.yy316);
 }
         break;
       case 22: /* ifnotexists ::= */
@@ -72699,9 +80846,9 @@ static void yy_reduce(
       case 101: /* ifexists ::= */
       case 112: /* distinct ::= ALL */
       case 113: /* distinct ::= */
-      case 213: /* between_op ::= BETWEEN */
-      case 216: /* in_op ::= IN */
-{yygotominor.yy46 = 0;}
+      case 216: /* between_op ::= BETWEEN */
+      case 219: /* in_op ::= IN */
+{yygotominor.yy316 = 0;}
         break;
       case 23: /* ifnotexists ::= IF NOT EXISTS */
       case 24: /* temp ::= TEMP */
@@ -72709,31 +80856,31 @@ static void yy_reduce(
       case 78: /* init_deferred_pred_opt ::= INITIALLY DEFERRED */
       case 100: /* ifexists ::= IF EXISTS */
       case 111: /* distinct ::= DISTINCT */
-      case 214: /* between_op ::= NOT BETWEEN */
-      case 217: /* in_op ::= NOT IN */
-{yygotominor.yy46 = 1;}
+      case 217: /* between_op ::= NOT BETWEEN */
+      case 220: /* in_op ::= NOT IN */
+{yygotominor.yy316 = 1;}
         break;
       case 26: /* create_table_args ::= LP columnlist conslist_opt RP */
 {
-  sqlite3EndTable(pParse,&yymsp[-1].minor.yy410,&yymsp[0].minor.yy0,0);
+  sqlite3EndTable(pParse,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0,0);
 }
         break;
       case 27: /* create_table_args ::= AS select */
 {
-  sqlite3EndTable(pParse,0,0,yymsp[0].minor.yy219);
-  sqlite3SelectDelete(yymsp[0].minor.yy219);
+  sqlite3EndTable(pParse,0,0,yymsp[0].minor.yy43);
+  sqlite3SelectDelete(pParse->db, yymsp[0].minor.yy43);
 }
         break;
       case 30: /* column ::= columnid type carglist */
 {
-  yygotominor.yy410.z = yymsp[-2].minor.yy410.z;
-  yygotominor.yy410.n = (pParse->sLastToken.z-yymsp[-2].minor.yy410.z) + pParse->sLastToken.n;
+  yygotominor.yy0.z = yymsp[-2].minor.yy0.z;
+  yygotominor.yy0.n = (pParse->sLastToken.z-yymsp[-2].minor.yy0.z) + pParse->sLastToken.n;
 }
         break;
       case 31: /* columnid ::= nm */
 {
-  sqlite3AddColumn(pParse,&yymsp[0].minor.yy410);
-  yygotominor.yy410 = yymsp[0].minor.yy410;
+  sqlite3AddColumn(pParse,&yymsp[0].minor.yy0);
+  yygotominor.yy0 = yymsp[0].minor.yy0;
 }
         break;
       case 32: /* id ::= ID */
@@ -72741,109 +80888,107 @@ static void yy_reduce(
       case 34: /* nm ::= ID */
       case 35: /* nm ::= STRING */
       case 36: /* nm ::= JOIN_KW */
-      case 256: /* number ::= INTEGER|FLOAT */
-{yygotominor.yy410 = yymsp[0].minor.yy0;}
-        break;
-      case 38: /* type ::= typetoken */
-{sqlite3AddColumnType(pParse,&yymsp[0].minor.yy410);}
-        break;
       case 39: /* typetoken ::= typename */
       case 42: /* typename ::= ids */
       case 119: /* as ::= AS nm */
       case 120: /* as ::= ids */
       case 131: /* dbnm ::= DOT nm */
-      case 241: /* idxitem ::= nm */
-      case 243: /* collate ::= COLLATE ids */
-      case 252: /* nmnum ::= plus_num */
-      case 253: /* nmnum ::= nm */
-      case 254: /* plus_num ::= plus_opt number */
-      case 255: /* minus_num ::= MINUS number */
-{yygotominor.yy410 = yymsp[0].minor.yy410;}
+      case 140: /* indexed_opt ::= INDEXED BY nm */
+      case 245: /* collate ::= COLLATE ids */
+      case 255: /* nmnum ::= plus_num */
+      case 256: /* nmnum ::= nm */
+      case 257: /* plus_num ::= plus_opt number */
+      case 258: /* minus_num ::= MINUS number */
+      case 259: /* number ::= INTEGER|FLOAT */
+{yygotominor.yy0 = yymsp[0].minor.yy0;}
+        break;
+      case 38: /* type ::= typetoken */
+{sqlite3AddColumnType(pParse,&yymsp[0].minor.yy0);}
         break;
       case 40: /* typetoken ::= typename LP signed RP */
 {
-  yygotominor.yy410.z = yymsp[-3].minor.yy410.z;
-  yygotominor.yy410.n = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n] - yymsp[-3].minor.yy410.z;
+  yygotominor.yy0.z = yymsp[-3].minor.yy0.z;
+  yygotominor.yy0.n = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n] - yymsp[-3].minor.yy0.z;
 }
         break;
       case 41: /* typetoken ::= typename LP signed COMMA signed RP */
 {
-  yygotominor.yy410.z = yymsp[-5].minor.yy410.z;
-  yygotominor.yy410.n = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n] - yymsp[-5].minor.yy410.z;
+  yygotominor.yy0.z = yymsp[-5].minor.yy0.z;
+  yygotominor.yy0.n = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n] - yymsp[-5].minor.yy0.z;
 }
         break;
       case 43: /* typename ::= typename ids */
-{yygotominor.yy410.z=yymsp[-1].minor.yy410.z; yygotominor.yy410.n=yymsp[0].minor.yy410.n+(yymsp[0].minor.yy410.z-yymsp[-1].minor.yy410.z);}
+{yygotominor.yy0.z=yymsp[-1].minor.yy0.z; yygotominor.yy0.n=yymsp[0].minor.yy0.n+(yymsp[0].minor.yy0.z-yymsp[-1].minor.yy0.z);}
         break;
       case 50: /* ccons ::= DEFAULT term */
       case 52: /* ccons ::= DEFAULT PLUS term */
-{sqlite3AddDefaultValue(pParse,yymsp[0].minor.yy172);}
+{sqlite3AddDefaultValue(pParse,yymsp[0].minor.yy450);}
         break;
       case 51: /* ccons ::= DEFAULT LP expr RP */
-{sqlite3AddDefaultValue(pParse,yymsp[-1].minor.yy172);}
+{sqlite3AddDefaultValue(pParse,yymsp[-1].minor.yy450);}
         break;
       case 53: /* ccons ::= DEFAULT MINUS term */
 {
-  Expr *p = sqlite3PExpr(pParse, TK_UMINUS, yymsp[0].minor.yy172, 0, 0);
+  Expr *p = sqlite3PExpr(pParse, TK_UMINUS, yymsp[0].minor.yy450, 0, 0);
   sqlite3AddDefaultValue(pParse,p);
 }
         break;
       case 54: /* ccons ::= DEFAULT id */
 {
-  Expr *p = sqlite3PExpr(pParse, TK_STRING, 0, 0, &yymsp[0].minor.yy410);
+  Expr *p = sqlite3PExpr(pParse, TK_STRING, 0, 0, &yymsp[0].minor.yy0);
   sqlite3AddDefaultValue(pParse,p);
 }
         break;
       case 56: /* ccons ::= NOT NULL onconf */
-{sqlite3AddNotNull(pParse, yymsp[0].minor.yy46);}
+{sqlite3AddNotNull(pParse, yymsp[0].minor.yy316);}
         break;
       case 57: /* ccons ::= PRIMARY KEY sortorder onconf autoinc */
-{sqlite3AddPrimaryKey(pParse,0,yymsp[-1].minor.yy46,yymsp[0].minor.yy46,yymsp[-2].minor.yy46);}
+{sqlite3AddPrimaryKey(pParse,0,yymsp[-1].minor.yy316,yymsp[0].minor.yy316,yymsp[-2].minor.yy316);}
         break;
       case 58: /* ccons ::= UNIQUE onconf */
-{sqlite3CreateIndex(pParse,0,0,0,0,yymsp[0].minor.yy46,0,0,0,0);}
+{sqlite3CreateIndex(pParse,0,0,0,0,yymsp[0].minor.yy316,0,0,0,0);}
         break;
       case 59: /* ccons ::= CHECK LP expr RP */
-{sqlite3AddCheckConstraint(pParse,yymsp[-1].minor.yy172);}
+{sqlite3AddCheckConstraint(pParse,yymsp[-1].minor.yy450);}
         break;
       case 60: /* ccons ::= REFERENCES nm idxlist_opt refargs */
-{sqlite3CreateForeignKey(pParse,0,&yymsp[-2].minor.yy410,yymsp[-1].minor.yy174,yymsp[0].minor.yy46);}
+{sqlite3CreateForeignKey(pParse,0,&yymsp[-2].minor.yy0,yymsp[-1].minor.yy242,yymsp[0].minor.yy316);}
         break;
       case 61: /* ccons ::= defer_subclause */
-{sqlite3DeferForeignKey(pParse,yymsp[0].minor.yy46);}
+{sqlite3DeferForeignKey(pParse,yymsp[0].minor.yy316);}
         break;
       case 62: /* ccons ::= COLLATE ids */
-{sqlite3AddCollateType(pParse, &yymsp[0].minor.yy410);}
+{sqlite3AddCollateType(pParse, &yymsp[0].minor.yy0);}
         break;
       case 65: /* refargs ::= */
-{ yygotominor.yy46 = OE_Restrict * 0x010101; }
+{ yygotominor.yy316 = OE_Restrict * 0x010101; }
         break;
       case 66: /* refargs ::= refargs refarg */
-{ yygotominor.yy46 = (yymsp[-1].minor.yy46 & yymsp[0].minor.yy405.mask) | yymsp[0].minor.yy405.value; }
+{ yygotominor.yy316 = (yymsp[-1].minor.yy316 & ~yymsp[0].minor.yy207.mask) | yymsp[0].minor.yy207.value; }
         break;
       case 67: /* refarg ::= MATCH nm */
-{ yygotominor.yy405.value = 0;     yygotominor.yy405.mask = 0x000000; }
+{ yygotominor.yy207.value = 0;     yygotominor.yy207.mask = 0x000000; }
         break;
       case 68: /* refarg ::= ON DELETE refact */
-{ yygotominor.yy405.value = yymsp[0].minor.yy46;     yygotominor.yy405.mask = 0x0000ff; }
+{ yygotominor.yy207.value = yymsp[0].minor.yy316;     yygotominor.yy207.mask = 0x0000ff; }
         break;
       case 69: /* refarg ::= ON UPDATE refact */
-{ yygotominor.yy405.value = yymsp[0].minor.yy46<<8;  yygotominor.yy405.mask = 0x00ff00; }
+{ yygotominor.yy207.value = yymsp[0].minor.yy316<<8;  yygotominor.yy207.mask = 0x00ff00; }
         break;
       case 70: /* refarg ::= ON INSERT refact */
-{ yygotominor.yy405.value = yymsp[0].minor.yy46<<16; yygotominor.yy405.mask = 0xff0000; }
+{ yygotominor.yy207.value = yymsp[0].minor.yy316<<16; yygotominor.yy207.mask = 0xff0000; }
         break;
       case 71: /* refact ::= SET NULL */
-{ yygotominor.yy46 = OE_SetNull; }
+{ yygotominor.yy316 = OE_SetNull; }
         break;
       case 72: /* refact ::= SET DEFAULT */
-{ yygotominor.yy46 = OE_SetDflt; }
+{ yygotominor.yy316 = OE_SetDflt; }
         break;
       case 73: /* refact ::= CASCADE */
-{ yygotominor.yy46 = OE_Cascade; }
+{ yygotominor.yy316 = OE_Cascade; }
         break;
       case 74: /* refact ::= RESTRICT */
-{ yygotominor.yy46 = OE_Restrict; }
+{ yygotominor.yy316 = OE_Restrict; }
         break;
       case 75: /* defer_subclause ::= NOT DEFERRABLE init_deferred_pred_opt */
       case 76: /* defer_subclause ::= DEFERRABLE init_deferred_pred_opt */
@@ -72851,743 +80996,760 @@ static void yy_reduce(
       case 93: /* onconf ::= ON CONFLICT resolvetype */
       case 95: /* orconf ::= OR resolvetype */
       case 96: /* resolvetype ::= raisetype */
-      case 166: /* insert_cmd ::= INSERT orconf */
-{yygotominor.yy46 = yymsp[0].minor.yy46;}
+      case 169: /* insert_cmd ::= INSERT orconf */
+{yygotominor.yy316 = yymsp[0].minor.yy316;}
         break;
       case 80: /* conslist_opt ::= */
-{yygotominor.yy410.n = 0; yygotominor.yy410.z = 0;}
+{yygotominor.yy0.n = 0; yygotominor.yy0.z = 0;}
         break;
       case 81: /* conslist_opt ::= COMMA conslist */
-{yygotominor.yy410 = yymsp[-1].minor.yy0;}
+{yygotominor.yy0 = yymsp[-1].minor.yy0;}
         break;
       case 86: /* tcons ::= PRIMARY KEY LP idxlist autoinc RP onconf */
-{sqlite3AddPrimaryKey(pParse,yymsp[-3].minor.yy174,yymsp[0].minor.yy46,yymsp[-2].minor.yy46,0);}
+{sqlite3AddPrimaryKey(pParse,yymsp[-3].minor.yy242,yymsp[0].minor.yy316,yymsp[-2].minor.yy316,0);}
         break;
       case 87: /* tcons ::= UNIQUE LP idxlist RP onconf */
-{sqlite3CreateIndex(pParse,0,0,0,yymsp[-2].minor.yy174,yymsp[0].minor.yy46,0,0,0,0);}
+{sqlite3CreateIndex(pParse,0,0,0,yymsp[-2].minor.yy242,yymsp[0].minor.yy316,0,0,0,0);}
         break;
       case 88: /* tcons ::= CHECK LP expr RP onconf */
-{sqlite3AddCheckConstraint(pParse,yymsp[-2].minor.yy172);}
+{sqlite3AddCheckConstraint(pParse,yymsp[-2].minor.yy450);}
         break;
       case 89: /* tcons ::= FOREIGN KEY LP idxlist RP REFERENCES nm idxlist_opt refargs defer_subclause_opt */
 {
-    sqlite3CreateForeignKey(pParse, yymsp[-6].minor.yy174, &yymsp[-3].minor.yy410, yymsp[-2].minor.yy174, yymsp[-1].minor.yy46);
-    sqlite3DeferForeignKey(pParse, yymsp[0].minor.yy46);
+    sqlite3CreateForeignKey(pParse, yymsp[-6].minor.yy242, &yymsp[-3].minor.yy0, yymsp[-2].minor.yy242, yymsp[-1].minor.yy316);
+    sqlite3DeferForeignKey(pParse, yymsp[0].minor.yy316);
 }
         break;
       case 92: /* onconf ::= */
       case 94: /* orconf ::= */
-{yygotominor.yy46 = OE_Default;}
+{yygotominor.yy316 = OE_Default;}
         break;
       case 97: /* resolvetype ::= IGNORE */
-{yygotominor.yy46 = OE_Ignore;}
+{yygotominor.yy316 = OE_Ignore;}
         break;
       case 98: /* resolvetype ::= REPLACE */
-      case 167: /* insert_cmd ::= REPLACE */
-{yygotominor.yy46 = OE_Replace;}
+      case 170: /* insert_cmd ::= REPLACE */
+{yygotominor.yy316 = OE_Replace;}
         break;
       case 99: /* cmd ::= DROP TABLE ifexists fullname */
 {
-  sqlite3DropTable(pParse, yymsp[0].minor.yy373, 0, yymsp[-1].minor.yy46);
+  sqlite3DropTable(pParse, yymsp[0].minor.yy419, 0, yymsp[-1].minor.yy316);
 }
         break;
       case 102: /* cmd ::= CREATE temp VIEW ifnotexists nm dbnm AS select */
 {
-  sqlite3CreateView(pParse, &yymsp[-7].minor.yy0, &yymsp[-3].minor.yy410, &yymsp[-2].minor.yy410, yymsp[0].minor.yy219, yymsp[-6].minor.yy46, yymsp[-4].minor.yy46);
+  sqlite3CreateView(pParse, &yymsp[-7].minor.yy0, &yymsp[-3].minor.yy0, &yymsp[-2].minor.yy0, yymsp[0].minor.yy43, yymsp[-6].minor.yy316, yymsp[-4].minor.yy316);
 }
         break;
       case 103: /* cmd ::= DROP VIEW ifexists fullname */
 {
-  sqlite3DropTable(pParse, yymsp[0].minor.yy373, 1, yymsp[-1].minor.yy46);
+  sqlite3DropTable(pParse, yymsp[0].minor.yy419, 1, yymsp[-1].minor.yy316);
 }
         break;
       case 104: /* cmd ::= select */
 {
-  SelectDest dest = {SRT_Callback, 0, 0};
-  sqlite3Select(pParse, yymsp[0].minor.yy219, &dest, 0, 0, 0, 0);
-  sqlite3SelectDelete(yymsp[0].minor.yy219);
+  SelectDest dest = {SRT_Output, 0, 0, 0, 0};
+  sqlite3Select(pParse, yymsp[0].minor.yy43, &dest);
+  sqlite3SelectDelete(pParse->db, yymsp[0].minor.yy43);
 }
         break;
       case 105: /* select ::= oneselect */
       case 128: /* seltablist_paren ::= select */
-{yygotominor.yy219 = yymsp[0].minor.yy219;}
+{yygotominor.yy43 = yymsp[0].minor.yy43;}
         break;
       case 106: /* select ::= select multiselect_op oneselect */
 {
-  if( yymsp[0].minor.yy219 ){
-    yymsp[0].minor.yy219->op = yymsp[-1].minor.yy46;
-    yymsp[0].minor.yy219->pPrior = yymsp[-2].minor.yy219;
+  if( yymsp[0].minor.yy43 ){
+    yymsp[0].minor.yy43->op = yymsp[-1].minor.yy316;
+    yymsp[0].minor.yy43->pPrior = yymsp[-2].minor.yy43;
   }else{
-    sqlite3SelectDelete(yymsp[-2].minor.yy219);
+    sqlite3SelectDelete(pParse->db, yymsp[-2].minor.yy43);
   }
-  yygotominor.yy219 = yymsp[0].minor.yy219;
+  yygotominor.yy43 = yymsp[0].minor.yy43;
 }
         break;
       case 108: /* multiselect_op ::= UNION ALL */
-{yygotominor.yy46 = TK_ALL;}
+{yygotominor.yy316 = TK_ALL;}
         break;
       case 110: /* oneselect ::= SELECT distinct selcollist from where_opt groupby_opt having_opt orderby_opt limit_opt */
 {
-  yygotominor.yy219 = sqlite3SelectNew(pParse,yymsp[-6].minor.yy174,yymsp[-5].minor.yy373,yymsp[-4].minor.yy172,yymsp[-3].minor.yy174,yymsp[-2].minor.yy172,yymsp[-1].minor.yy174,yymsp[-7].minor.yy46,yymsp[0].minor.yy234.pLimit,yymsp[0].minor.yy234.pOffset);
+  yygotominor.yy43 = sqlite3SelectNew(pParse,yymsp[-6].minor.yy242,yymsp[-5].minor.yy419,yymsp[-4].minor.yy450,yymsp[-3].minor.yy242,yymsp[-2].minor.yy450,yymsp[-1].minor.yy242,yymsp[-7].minor.yy316,yymsp[0].minor.yy84.pLimit,yymsp[0].minor.yy84.pOffset);
 }
         break;
       case 114: /* sclp ::= selcollist COMMA */
-      case 238: /* idxlist_opt ::= LP idxlist RP */
-{yygotominor.yy174 = yymsp[-1].minor.yy174;}
+      case 241: /* idxlist_opt ::= LP idxlist RP */
+{yygotominor.yy242 = yymsp[-1].minor.yy242;}
         break;
       case 115: /* sclp ::= */
-      case 141: /* orderby_opt ::= */
-      case 149: /* groupby_opt ::= */
-      case 231: /* exprlist ::= */
-      case 237: /* idxlist_opt ::= */
-{yygotominor.yy174 = 0;}
+      case 144: /* orderby_opt ::= */
+      case 152: /* groupby_opt ::= */
+      case 234: /* exprlist ::= */
+      case 240: /* idxlist_opt ::= */
+{yygotominor.yy242 = 0;}
         break;
       case 116: /* selcollist ::= sclp expr as */
 {
-   yygotominor.yy174 = sqlite3ExprListAppend(pParse,yymsp[-2].minor.yy174,yymsp[-1].minor.yy172,yymsp[0].minor.yy410.n?&yymsp[0].minor.yy410:0);
+   yygotominor.yy242 = sqlite3ExprListAppend(pParse,yymsp[-2].minor.yy242,yymsp[-1].minor.yy450,yymsp[0].minor.yy0.n?&yymsp[0].minor.yy0:0);
 }
         break;
       case 117: /* selcollist ::= sclp STAR */
 {
   Expr *p = sqlite3PExpr(pParse, TK_ALL, 0, 0, 0);
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse, yymsp[-1].minor.yy174, p, 0);
+  yygotominor.yy242 = sqlite3ExprListAppend(pParse, yymsp[-1].minor.yy242, p, 0);
 }
         break;
       case 118: /* selcollist ::= sclp nm DOT STAR */
 {
-  Expr *pRight = sqlite3PExpr(pParse, TK_ALL, 0, 0, 0);
-  Expr *pLeft = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy410);
+  Expr *pRight = sqlite3PExpr(pParse, TK_ALL, 0, 0, &yymsp[0].minor.yy0);
+  Expr *pLeft = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy0);
   Expr *pDot = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight, 0);
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy174, pDot, 0);
+  yygotominor.yy242 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy242, pDot, 0);
 }
         break;
       case 121: /* as ::= */
-{yygotominor.yy410.n = 0;}
+{yygotominor.yy0.n = 0;}
         break;
       case 122: /* from ::= */
-{yygotominor.yy373 = sqlite3DbMallocZero(pParse->db, sizeof(*yygotominor.yy373));}
+{yygotominor.yy419 = sqlite3DbMallocZero(pParse->db, sizeof(*yygotominor.yy419));}
         break;
       case 123: /* from ::= FROM seltablist */
 {
-  yygotominor.yy373 = yymsp[0].minor.yy373;
-  sqlite3SrcListShiftJoinType(yygotominor.yy373);
+  yygotominor.yy419 = yymsp[0].minor.yy419;
+  sqlite3SrcListShiftJoinType(yygotominor.yy419);
 }
         break;
       case 124: /* stl_prefix ::= seltablist joinop */
 {
-   yygotominor.yy373 = yymsp[-1].minor.yy373;
-   if( yygotominor.yy373 && yygotominor.yy373->nSrc>0 ) yygotominor.yy373->a[yygotominor.yy373->nSrc-1].jointype = yymsp[0].minor.yy46;
+   yygotominor.yy419 = yymsp[-1].minor.yy419;
+   if( yygotominor.yy419 && yygotominor.yy419->nSrc>0 ) yygotominor.yy419->a[yygotominor.yy419->nSrc-1].jointype = yymsp[0].minor.yy316;
 }
         break;
       case 125: /* stl_prefix ::= */
-{yygotominor.yy373 = 0;}
+{yygotominor.yy419 = 0;}
         break;
-      case 126: /* seltablist ::= stl_prefix nm dbnm as on_opt using_opt */
+      case 126: /* seltablist ::= stl_prefix nm dbnm as indexed_opt on_opt using_opt */
 {
-  yygotominor.yy373 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-5].minor.yy373,&yymsp[-4].minor.yy410,&yymsp[-3].minor.yy410,&yymsp[-2].minor.yy410,0,yymsp[-1].minor.yy172,yymsp[0].minor.yy432);
+  yygotominor.yy419 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy419,&yymsp[-5].minor.yy0,&yymsp[-4].minor.yy0,&yymsp[-3].minor.yy0,0,yymsp[-1].minor.yy450,yymsp[0].minor.yy352);
+  sqlite3SrcListIndexedBy(pParse, yygotominor.yy419, &yymsp[-2].minor.yy0);
 }
         break;
       case 127: /* seltablist ::= stl_prefix LP seltablist_paren RP as on_opt using_opt */
 {
-    yygotominor.yy373 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy373,0,0,&yymsp[-2].minor.yy410,yymsp[-4].minor.yy219,yymsp[-1].minor.yy172,yymsp[0].minor.yy432);
+    yygotominor.yy419 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy419,0,0,&yymsp[-2].minor.yy0,yymsp[-4].minor.yy43,yymsp[-1].minor.yy450,yymsp[0].minor.yy352);
   }
         break;
       case 129: /* seltablist_paren ::= seltablist */
 {
-     sqlite3SrcListShiftJoinType(yymsp[0].minor.yy373);
-     yygotominor.yy219 = sqlite3SelectNew(pParse,0,yymsp[0].minor.yy373,0,0,0,0,0,0,0);
+     sqlite3SrcListShiftJoinType(yymsp[0].minor.yy419);
+     yygotominor.yy43 = sqlite3SelectNew(pParse,0,yymsp[0].minor.yy419,0,0,0,0,0,0,0);
   }
         break;
       case 130: /* dbnm ::= */
-{yygotominor.yy410.z=0; yygotominor.yy410.n=0;}
+      case 139: /* indexed_opt ::= */
+{yygotominor.yy0.z=0; yygotominor.yy0.n=0;}
         break;
       case 132: /* fullname ::= nm dbnm */
-{yygotominor.yy373 = sqlite3SrcListAppend(pParse->db,0,&yymsp[-1].minor.yy410,&yymsp[0].minor.yy410);}
+{yygotominor.yy419 = sqlite3SrcListAppend(pParse->db,0,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0);}
         break;
       case 133: /* joinop ::= COMMA|JOIN */
-{ yygotominor.yy46 = JT_INNER; }
+{ yygotominor.yy316 = JT_INNER; }
         break;
       case 134: /* joinop ::= JOIN_KW JOIN */
-{ yygotominor.yy46 = sqlite3JoinType(pParse,&yymsp[-1].minor.yy0,0,0); }
+{ yygotominor.yy316 = sqlite3JoinType(pParse,&yymsp[-1].minor.yy0,0,0); }
         break;
       case 135: /* joinop ::= JOIN_KW nm JOIN */
-{ yygotominor.yy46 = sqlite3JoinType(pParse,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy410,0); }
+{ yygotominor.yy316 = sqlite3JoinType(pParse,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy0,0); }
         break;
       case 136: /* joinop ::= JOIN_KW nm nm JOIN */
-{ yygotominor.yy46 = sqlite3JoinType(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy410,&yymsp[-1].minor.yy410); }
+{ yygotominor.yy316 = sqlite3JoinType(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy0); }
         break;
       case 137: /* on_opt ::= ON expr */
-      case 145: /* sortitem ::= expr */
-      case 152: /* having_opt ::= HAVING expr */
-      case 159: /* where_opt ::= WHERE expr */
-      case 174: /* expr ::= term */
-      case 202: /* escape ::= ESCAPE expr */
-      case 226: /* case_else ::= ELSE expr */
-      case 228: /* case_operand ::= expr */
-{yygotominor.yy172 = yymsp[0].minor.yy172;}
+      case 148: /* sortitem ::= expr */
+      case 155: /* having_opt ::= HAVING expr */
+      case 162: /* where_opt ::= WHERE expr */
+      case 177: /* expr ::= term */
+      case 205: /* escape ::= ESCAPE expr */
+      case 229: /* case_else ::= ELSE expr */
+      case 231: /* case_operand ::= expr */
+{yygotominor.yy450 = yymsp[0].minor.yy450;}
         break;
       case 138: /* on_opt ::= */
-      case 151: /* having_opt ::= */
-      case 158: /* where_opt ::= */
-      case 203: /* escape ::= */
-      case 227: /* case_else ::= */
-      case 229: /* case_operand ::= */
-{yygotominor.yy172 = 0;}
+      case 154: /* having_opt ::= */
+      case 161: /* where_opt ::= */
+      case 206: /* escape ::= */
+      case 230: /* case_else ::= */
+      case 232: /* case_operand ::= */
+{yygotominor.yy450 = 0;}
+        break;
+      case 141: /* indexed_opt ::= NOT INDEXED */
+{yygotominor.yy0.z=0; yygotominor.yy0.n=1;}
         break;
-      case 139: /* using_opt ::= USING LP inscollist RP */
-      case 171: /* inscollist_opt ::= LP inscollist RP */
-{yygotominor.yy432 = yymsp[-1].minor.yy432;}
+      case 142: /* using_opt ::= USING LP inscollist RP */
+      case 174: /* inscollist_opt ::= LP inscollist RP */
+{yygotominor.yy352 = yymsp[-1].minor.yy352;}
         break;
-      case 140: /* using_opt ::= */
-      case 170: /* inscollist_opt ::= */
-{yygotominor.yy432 = 0;}
+      case 143: /* using_opt ::= */
+      case 173: /* inscollist_opt ::= */
+{yygotominor.yy352 = 0;}
         break;
-      case 142: /* orderby_opt ::= ORDER BY sortlist */
-      case 150: /* groupby_opt ::= GROUP BY nexprlist */
-      case 230: /* exprlist ::= nexprlist */
-{yygotominor.yy174 = yymsp[0].minor.yy174;}
+      case 145: /* orderby_opt ::= ORDER BY sortlist */
+      case 153: /* groupby_opt ::= GROUP BY nexprlist */
+      case 233: /* exprlist ::= nexprlist */
+{yygotominor.yy242 = yymsp[0].minor.yy242;}
         break;
-      case 143: /* sortlist ::= sortlist COMMA sortitem sortorder */
+      case 146: /* sortlist ::= sortlist COMMA sortitem sortorder */
 {
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy174,yymsp[-1].minor.yy172,0);
-  if( yygotominor.yy174 ) yygotominor.yy174->a[yygotominor.yy174->nExpr-1].sortOrder = yymsp[0].minor.yy46;
+  yygotominor.yy242 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy242,yymsp[-1].minor.yy450,0);
+  if( yygotominor.yy242 ) yygotominor.yy242->a[yygotominor.yy242->nExpr-1].sortOrder = yymsp[0].minor.yy316;
 }
         break;
-      case 144: /* sortlist ::= sortitem sortorder */
+      case 147: /* sortlist ::= sortitem sortorder */
 {
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,0,yymsp[-1].minor.yy172,0);
-  if( yygotominor.yy174 && yygotominor.yy174->a ) yygotominor.yy174->a[0].sortOrder = yymsp[0].minor.yy46;
+  yygotominor.yy242 = sqlite3ExprListAppend(pParse,0,yymsp[-1].minor.yy450,0);
+  if( yygotominor.yy242 && yygotominor.yy242->a ) yygotominor.yy242->a[0].sortOrder = yymsp[0].minor.yy316;
 }
         break;
-      case 146: /* sortorder ::= ASC */
-      case 148: /* sortorder ::= */
-{yygotominor.yy46 = SQLITE_SO_ASC;}
+      case 149: /* sortorder ::= ASC */
+      case 151: /* sortorder ::= */
+{yygotominor.yy316 = SQLITE_SO_ASC;}
         break;
-      case 147: /* sortorder ::= DESC */
-{yygotominor.yy46 = SQLITE_SO_DESC;}
+      case 150: /* sortorder ::= DESC */
+{yygotominor.yy316 = SQLITE_SO_DESC;}
         break;
-      case 153: /* limit_opt ::= */
-{yygotominor.yy234.pLimit = 0; yygotominor.yy234.pOffset = 0;}
+      case 156: /* limit_opt ::= */
+{yygotominor.yy84.pLimit = 0; yygotominor.yy84.pOffset = 0;}
         break;
-      case 154: /* limit_opt ::= LIMIT expr */
-{yygotominor.yy234.pLimit = yymsp[0].minor.yy172; yygotominor.yy234.pOffset = 0;}
+      case 157: /* limit_opt ::= LIMIT expr */
+{yygotominor.yy84.pLimit = yymsp[0].minor.yy450; yygotominor.yy84.pOffset = 0;}
         break;
-      case 155: /* limit_opt ::= LIMIT expr OFFSET expr */
-{yygotominor.yy234.pLimit = yymsp[-2].minor.yy172; yygotominor.yy234.pOffset = yymsp[0].minor.yy172;}
+      case 158: /* limit_opt ::= LIMIT expr OFFSET expr */
+{yygotominor.yy84.pLimit = yymsp[-2].minor.yy450; yygotominor.yy84.pOffset = yymsp[0].minor.yy450;}
         break;
-      case 156: /* limit_opt ::= LIMIT expr COMMA expr */
-{yygotominor.yy234.pOffset = yymsp[-2].minor.yy172; yygotominor.yy234.pLimit = yymsp[0].minor.yy172;}
+      case 159: /* limit_opt ::= LIMIT expr COMMA expr */
+{yygotominor.yy84.pOffset = yymsp[-2].minor.yy450; yygotominor.yy84.pLimit = yymsp[0].minor.yy450;}
         break;
-      case 157: /* cmd ::= DELETE FROM fullname where_opt */
-{sqlite3DeleteFrom(pParse,yymsp[-1].minor.yy373,yymsp[0].minor.yy172);}
+      case 160: /* cmd ::= DELETE FROM fullname indexed_opt where_opt */
+{
+  sqlite3SrcListIndexedBy(pParse, yymsp[-2].minor.yy419, &yymsp[-1].minor.yy0);
+  sqlite3DeleteFrom(pParse,yymsp[-2].minor.yy419,yymsp[0].minor.yy450);
+}
         break;
-      case 160: /* cmd ::= UPDATE orconf fullname SET setlist where_opt */
+      case 163: /* cmd ::= UPDATE orconf fullname indexed_opt SET setlist where_opt */
 {
-  sqlite3ExprListCheckLength(pParse,yymsp[-1].minor.yy174,SQLITE_MAX_COLUMN,"set list"); 
-  sqlite3Update(pParse,yymsp[-3].minor.yy373,yymsp[-1].minor.yy174,yymsp[0].minor.yy172,yymsp[-4].minor.yy46);
+  sqlite3SrcListIndexedBy(pParse, yymsp[-4].minor.yy419, &yymsp[-3].minor.yy0);
+  sqlite3ExprListCheckLength(pParse,yymsp[-1].minor.yy242,"set list"); 
+  sqlite3Update(pParse,yymsp[-4].minor.yy419,yymsp[-1].minor.yy242,yymsp[0].minor.yy450,yymsp[-5].minor.yy316);
 }
         break;
-      case 161: /* setlist ::= setlist COMMA nm EQ expr */
-{yygotominor.yy174 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy174,yymsp[0].minor.yy172,&yymsp[-2].minor.yy410);}
+      case 164: /* setlist ::= setlist COMMA nm EQ expr */
+{yygotominor.yy242 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy242,yymsp[0].minor.yy450,&yymsp[-2].minor.yy0);}
         break;
-      case 162: /* setlist ::= nm EQ expr */
-{yygotominor.yy174 = sqlite3ExprListAppend(pParse,0,yymsp[0].minor.yy172,&yymsp[-2].minor.yy410);}
+      case 165: /* setlist ::= nm EQ expr */
+{yygotominor.yy242 = sqlite3ExprListAppend(pParse,0,yymsp[0].minor.yy450,&yymsp[-2].minor.yy0);}
         break;
-      case 163: /* cmd ::= insert_cmd INTO fullname inscollist_opt VALUES LP itemlist RP */
-{sqlite3Insert(pParse, yymsp[-5].minor.yy373, yymsp[-1].minor.yy174, 0, yymsp[-4].minor.yy432, yymsp[-7].minor.yy46);}
+      case 166: /* cmd ::= insert_cmd INTO fullname inscollist_opt VALUES LP itemlist RP */
+{sqlite3Insert(pParse, yymsp[-5].minor.yy419, yymsp[-1].minor.yy242, 0, yymsp[-4].minor.yy352, yymsp[-7].minor.yy316);}
         break;
-      case 164: /* cmd ::= insert_cmd INTO fullname inscollist_opt select */
-{sqlite3Insert(pParse, yymsp[-2].minor.yy373, 0, yymsp[0].minor.yy219, yymsp[-1].minor.yy432, yymsp[-4].minor.yy46);}
+      case 167: /* cmd ::= insert_cmd INTO fullname inscollist_opt select */
+{sqlite3Insert(pParse, yymsp[-2].minor.yy419, 0, yymsp[0].minor.yy43, yymsp[-1].minor.yy352, yymsp[-4].minor.yy316);}
         break;
-      case 165: /* cmd ::= insert_cmd INTO fullname inscollist_opt DEFAULT VALUES */
-{sqlite3Insert(pParse, yymsp[-3].minor.yy373, 0, 0, yymsp[-2].minor.yy432, yymsp[-5].minor.yy46);}
+      case 168: /* cmd ::= insert_cmd INTO fullname inscollist_opt DEFAULT VALUES */
+{sqlite3Insert(pParse, yymsp[-3].minor.yy419, 0, 0, yymsp[-2].minor.yy352, yymsp[-5].minor.yy316);}
         break;
-      case 168: /* itemlist ::= itemlist COMMA expr */
-      case 232: /* nexprlist ::= nexprlist COMMA expr */
-{yygotominor.yy174 = sqlite3ExprListAppend(pParse,yymsp[-2].minor.yy174,yymsp[0].minor.yy172,0);}
+      case 171: /* itemlist ::= itemlist COMMA expr */
+      case 235: /* nexprlist ::= nexprlist COMMA expr */
+{yygotominor.yy242 = sqlite3ExprListAppend(pParse,yymsp[-2].minor.yy242,yymsp[0].minor.yy450,0);}
         break;
-      case 169: /* itemlist ::= expr */
-      case 233: /* nexprlist ::= expr */
-{yygotominor.yy174 = sqlite3ExprListAppend(pParse,0,yymsp[0].minor.yy172,0);}
+      case 172: /* itemlist ::= expr */
+      case 236: /* nexprlist ::= expr */
+{yygotominor.yy242 = sqlite3ExprListAppend(pParse,0,yymsp[0].minor.yy450,0);}
         break;
-      case 172: /* inscollist ::= inscollist COMMA nm */
-{yygotominor.yy432 = sqlite3IdListAppend(pParse->db,yymsp[-2].minor.yy432,&yymsp[0].minor.yy410);}
+      case 175: /* inscollist ::= inscollist COMMA nm */
+{yygotominor.yy352 = sqlite3IdListAppend(pParse->db,yymsp[-2].minor.yy352,&yymsp[0].minor.yy0);}
         break;
-      case 173: /* inscollist ::= nm */
-{yygotominor.yy432 = sqlite3IdListAppend(pParse->db,0,&yymsp[0].minor.yy410);}
+      case 176: /* inscollist ::= nm */
+{yygotominor.yy352 = sqlite3IdListAppend(pParse->db,0,&yymsp[0].minor.yy0);}
         break;
-      case 175: /* expr ::= LP expr RP */
-{yygotominor.yy172 = yymsp[-1].minor.yy172; sqlite3ExprSpan(yygotominor.yy172,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0); }
+      case 178: /* expr ::= LP expr RP */
+{yygotominor.yy450 = yymsp[-1].minor.yy450; sqlite3ExprSpan(yygotominor.yy450,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0); }
         break;
-      case 176: /* term ::= NULL */
-      case 181: /* term ::= INTEGER|FLOAT|BLOB */
-      case 182: /* term ::= STRING */
-{yygotominor.yy172 = sqlite3PExpr(pParse, yymsp[0].major, 0, 0, &yymsp[0].minor.yy0);}
+      case 179: /* term ::= NULL */
+      case 184: /* term ::= INTEGER|FLOAT|BLOB */
+      case 185: /* term ::= STRING */
+{yygotominor.yy450 = sqlite3PExpr(pParse, yymsp[0].major, 0, 0, &yymsp[0].minor.yy0);}
         break;
-      case 177: /* expr ::= ID */
-      case 178: /* expr ::= JOIN_KW */
-{yygotominor.yy172 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy0);}
+      case 180: /* expr ::= ID */
+      case 181: /* expr ::= JOIN_KW */
+{yygotominor.yy450 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy0);}
         break;
-      case 179: /* expr ::= nm DOT nm */
+      case 182: /* expr ::= nm DOT nm */
 {
-  Expr *temp1 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy410);
-  Expr *temp2 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy410);
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_DOT, temp1, temp2, 0);
+  Expr *temp1 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy0);
+  Expr *temp2 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy0);
+  yygotominor.yy450 = sqlite3PExpr(pParse, TK_DOT, temp1, temp2, 0);
 }
         break;
-      case 180: /* expr ::= nm DOT nm DOT nm */
+      case 183: /* expr ::= nm DOT nm DOT nm */
 {
-  Expr *temp1 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-4].minor.yy410);
-  Expr *temp2 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy410);
-  Expr *temp3 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy410);
+  Expr *temp1 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-4].minor.yy0);
+  Expr *temp2 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy0);
+  Expr *temp3 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy0);
   Expr *temp4 = sqlite3PExpr(pParse, TK_DOT, temp2, temp3, 0);
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_DOT, temp1, temp4, 0);
+  yygotominor.yy450 = sqlite3PExpr(pParse, TK_DOT, temp1, temp4, 0);
 }
         break;
-      case 183: /* expr ::= REGISTER */
-{yygotominor.yy172 = sqlite3RegisterExpr(pParse, &yymsp[0].minor.yy0);}
+      case 186: /* expr ::= REGISTER */
+{yygotominor.yy450 = sqlite3RegisterExpr(pParse, &yymsp[0].minor.yy0);}
         break;
-      case 184: /* expr ::= VARIABLE */
+      case 187: /* expr ::= VARIABLE */
 {
   Token *pToken = &yymsp[0].minor.yy0;
-  Expr *pExpr = yygotominor.yy172 = sqlite3PExpr(pParse, TK_VARIABLE, 0, 0, pToken);
+  Expr *pExpr = yygotominor.yy450 = sqlite3PExpr(pParse, TK_VARIABLE, 0, 0, pToken);
   sqlite3ExprAssignVarNumber(pParse, pExpr);
 }
         break;
-      case 185: /* expr ::= expr COLLATE ids */
+      case 188: /* expr ::= expr COLLATE ids */
 {
-  yygotominor.yy172 = sqlite3ExprSetColl(pParse, yymsp[-2].minor.yy172, &yymsp[0].minor.yy410);
+  yygotominor.yy450 = sqlite3ExprSetColl(pParse, yymsp[-2].minor.yy450, &yymsp[0].minor.yy0);
 }
         break;
-      case 186: /* expr ::= CAST LP expr AS typetoken RP */
+      case 189: /* expr ::= CAST LP expr AS typetoken RP */
 {
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_CAST, yymsp[-3].minor.yy172, 0, &yymsp[-1].minor.yy410);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-5].minor.yy0,&yymsp[0].minor.yy0);
+  yygotominor.yy450 = sqlite3PExpr(pParse, TK_CAST, yymsp[-3].minor.yy450, 0, &yymsp[-1].minor.yy0);
+  sqlite3ExprSpan(yygotominor.yy450,&yymsp[-5].minor.yy0,&yymsp[0].minor.yy0);
 }
         break;
-      case 187: /* expr ::= ID LP distinct exprlist RP */
+      case 190: /* expr ::= ID LP distinct exprlist RP */
 {
-  if( yymsp[-1].minor.yy174 && yymsp[-1].minor.yy174->nExpr>SQLITE_MAX_FUNCTION_ARG ){
+  if( yymsp[-1].minor.yy242 && yymsp[-1].minor.yy242->nExpr>SQLITE_MAX_FUNCTION_ARG ){
     sqlite3ErrorMsg(pParse, "too many arguments on function %T", &yymsp[-4].minor.yy0);
   }
-  yygotominor.yy172 = sqlite3ExprFunction(pParse, yymsp[-1].minor.yy174, &yymsp[-4].minor.yy0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-4].minor.yy0,&yymsp[0].minor.yy0);
-  if( yymsp[-2].minor.yy46 && yygotominor.yy172 ){
-    yygotominor.yy172->flags |= EP_Distinct;
+  yygotominor.yy450 = sqlite3ExprFunction(pParse, yymsp[-1].minor.yy242, &yymsp[-4].minor.yy0);
+  sqlite3ExprSpan(yygotominor.yy450,&yymsp[-4].minor.yy0,&yymsp[0].minor.yy0);
+  if( yymsp[-2].minor.yy316 && yygotominor.yy450 ){
+    yygotominor.yy450->flags |= EP_Distinct;
   }
 }
         break;
-      case 188: /* expr ::= ID LP STAR RP */
+      case 191: /* expr ::= ID LP STAR RP */
 {
-  yygotominor.yy172 = sqlite3ExprFunction(pParse, 0, &yymsp[-3].minor.yy0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-3].minor.yy0,&yymsp[0].minor.yy0);
+  yygotominor.yy450 = sqlite3ExprFunction(pParse, 0, &yymsp[-3].minor.yy0);
+  sqlite3ExprSpan(yygotominor.yy450,&yymsp[-3].minor.yy0,&yymsp[0].minor.yy0);
 }
         break;
-      case 189: /* term ::= CTIME_KW */
+      case 192: /* term ::= CTIME_KW */
 {
   /* The CURRENT_TIME, CURRENT_DATE, and CURRENT_TIMESTAMP values are
   ** treated as functions that return constants */
-  yygotominor.yy172 = sqlite3ExprFunction(pParse, 0,&yymsp[0].minor.yy0);
-  if( yygotominor.yy172 ){
-    yygotominor.yy172->op = TK_CONST_FUNC;  
-    yygotominor.yy172->span = yymsp[0].minor.yy0;
+  yygotominor.yy450 = sqlite3ExprFunction(pParse, 0,&yymsp[0].minor.yy0);
+  if( yygotominor.yy450 ){
+    yygotominor.yy450->op = TK_CONST_FUNC;  
+    yygotominor.yy450->span = yymsp[0].minor.yy0;
   }
 }
         break;
-      case 190: /* expr ::= expr AND expr */
-      case 191: /* expr ::= expr OR expr */
-      case 192: /* expr ::= expr LT|GT|GE|LE expr */
-      case 193: /* expr ::= expr EQ|NE expr */
-      case 194: /* expr ::= expr BITAND|BITOR|LSHIFT|RSHIFT expr */
-      case 195: /* expr ::= expr PLUS|MINUS expr */
-      case 196: /* expr ::= expr STAR|SLASH|REM expr */
-      case 197: /* expr ::= expr CONCAT expr */
-{yygotominor.yy172 = sqlite3PExpr(pParse,yymsp[-1].major,yymsp[-2].minor.yy172,yymsp[0].minor.yy172,0);}
+      case 193: /* expr ::= expr AND expr */
+      case 194: /* expr ::= expr OR expr */
+      case 195: /* expr ::= expr LT|GT|GE|LE expr */
+      case 196: /* expr ::= expr EQ|NE expr */
+      case 197: /* expr ::= expr BITAND|BITOR|LSHIFT|RSHIFT expr */
+      case 198: /* expr ::= expr PLUS|MINUS expr */
+      case 199: /* expr ::= expr STAR|SLASH|REM expr */
+      case 200: /* expr ::= expr CONCAT expr */
+{yygotominor.yy450 = sqlite3PExpr(pParse,yymsp[-1].major,yymsp[-2].minor.yy450,yymsp[0].minor.yy450,0);}
         break;
-      case 198: /* likeop ::= LIKE_KW */
-      case 200: /* likeop ::= MATCH */
-{yygotominor.yy72.eOperator = yymsp[0].minor.yy0; yygotominor.yy72.not = 0;}
+      case 201: /* likeop ::= LIKE_KW */
+      case 203: /* likeop ::= MATCH */
+{yygotominor.yy86.eOperator = yymsp[0].minor.yy0; yygotominor.yy86.not = 0;}
         break;
-      case 199: /* likeop ::= NOT LIKE_KW */
-      case 201: /* likeop ::= NOT MATCH */
-{yygotominor.yy72.eOperator = yymsp[0].minor.yy0; yygotominor.yy72.not = 1;}
+      case 202: /* likeop ::= NOT LIKE_KW */
+      case 204: /* likeop ::= NOT MATCH */
+{yygotominor.yy86.eOperator = yymsp[0].minor.yy0; yygotominor.yy86.not = 1;}
         break;
-      case 204: /* expr ::= expr likeop expr escape */
+      case 207: /* expr ::= expr likeop expr escape */
 {
   ExprList *pList;
-  pList = sqlite3ExprListAppend(pParse,0, yymsp[-1].minor.yy172, 0);
-  pList = sqlite3ExprListAppend(pParse,pList, yymsp[-3].minor.yy172, 0);
-  if( yymsp[0].minor.yy172 ){
-    pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy172, 0);
+  pList = sqlite3ExprListAppend(pParse,0, yymsp[-1].minor.yy450, 0);
+  pList = sqlite3ExprListAppend(pParse,pList, yymsp[-3].minor.yy450, 0);
+  if( yymsp[0].minor.yy450 ){
+    pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy450, 0);
   }
-  yygotominor.yy172 = sqlite3ExprFunction(pParse, pList, &yymsp[-2].minor.yy72.eOperator);
-  if( yymsp[-2].minor.yy72.not ) yygotominor.yy172 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172, &yymsp[-3].minor.yy172->span, &yymsp[-1].minor.yy172->span);
-  if( yygotominor.yy172 ) yygotominor.yy172->flags |= EP_InfixFunc;
+  yygotominor.yy450 = sqlite3ExprFunction(pParse, pList, &yymsp[-2].minor.yy86.eOperator);
+  if( yymsp[-2].minor.yy86.not ) yygotominor.yy450 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy450, 0, 0);
+  sqlite3ExprSpan(yygotominor.yy450, &yymsp[-3].minor.yy450->span, &yymsp[-1].minor.yy450->span);
+  if( yygotominor.yy450 ) yygotominor.yy450->flags |= EP_InfixFunc;
 }
         break;
-      case 205: /* expr ::= expr ISNULL|NOTNULL */
+      case 208: /* expr ::= expr ISNULL|NOTNULL */
 {
-  yygotominor.yy172 = sqlite3PExpr(pParse, yymsp[0].major, yymsp[-1].minor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-1].minor.yy172->span,&yymsp[0].minor.yy0);
+  yygotominor.yy450 = sqlite3PExpr(pParse, yymsp[0].major, yymsp[-1].minor.yy450, 0, 0);
+  sqlite3ExprSpan(yygotominor.yy450,&yymsp[-1].minor.yy450->span,&yymsp[0].minor.yy0);
 }
         break;
-      case 206: /* expr ::= expr IS NULL */
+      case 209: /* expr ::= expr IS NULL */
 {
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_ISNULL, yymsp[-2].minor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-2].minor.yy172->span,&yymsp[0].minor.yy0);
+  yygotominor.yy450 = sqlite3PExpr(pParse, TK_ISNULL, yymsp[-2].minor.yy450, 0, 0);
+  sqlite3ExprSpan(yygotominor.yy450,&yymsp[-2].minor.yy450->span,&yymsp[0].minor.yy0);
 }
         break;
-      case 207: /* expr ::= expr NOT NULL */
+      case 210: /* expr ::= expr NOT NULL */
 {
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_NOTNULL, yymsp[-2].minor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-2].minor.yy172->span,&yymsp[0].minor.yy0);
+  yygotominor.yy450 = sqlite3PExpr(pParse, TK_NOTNULL, yymsp[-2].minor.yy450, 0, 0);
+  sqlite3ExprSpan(yygotominor.yy450,&yymsp[-2].minor.yy450->span,&yymsp[0].minor.yy0);
 }
         break;
-      case 208: /* expr ::= expr IS NOT NULL */
+      case 211: /* expr ::= expr IS NOT NULL */
 {
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_NOTNULL, yymsp[-3].minor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-3].minor.yy172->span,&yymsp[0].minor.yy0);
+  yygotominor.yy450 = sqlite3PExpr(pParse, TK_NOTNULL, yymsp[-3].minor.yy450, 0, 0);
+  sqlite3ExprSpan(yygotominor.yy450,&yymsp[-3].minor.yy450->span,&yymsp[0].minor.yy0);
 }
         break;
-      case 209: /* expr ::= NOT expr */
-      case 210: /* expr ::= BITNOT expr */
+      case 212: /* expr ::= NOT expr */
+      case 213: /* expr ::= BITNOT expr */
 {
-  yygotominor.yy172 = sqlite3PExpr(pParse, yymsp[-1].major, yymsp[0].minor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy172->span);
+  yygotominor.yy450 = sqlite3PExpr(pParse, yymsp[-1].major, yymsp[0].minor.yy450, 0, 0);
+  sqlite3ExprSpan(yygotominor.yy450,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy450->span);
 }
         break;
-      case 211: /* expr ::= MINUS expr */
+      case 214: /* expr ::= MINUS expr */
 {
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_UMINUS, yymsp[0].minor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy172->span);
+  yygotominor.yy450 = sqlite3PExpr(pParse, TK_UMINUS, yymsp[0].minor.yy450, 0, 0);
+  sqlite3ExprSpan(yygotominor.yy450,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy450->span);
 }
         break;
-      case 212: /* expr ::= PLUS expr */
+      case 215: /* expr ::= PLUS expr */
 {
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_UPLUS, yymsp[0].minor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy172->span);
+  yygotominor.yy450 = sqlite3PExpr(pParse, TK_UPLUS, yymsp[0].minor.yy450, 0, 0);
+  sqlite3ExprSpan(yygotominor.yy450,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy450->span);
 }
         break;
-      case 215: /* expr ::= expr between_op expr AND expr */
+      case 218: /* expr ::= expr between_op expr AND expr */
 {
-  ExprList *pList = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy172, 0);
-  pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy172, 0);
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_BETWEEN, yymsp[-4].minor.yy172, 0, 0);
-  if( yygotominor.yy172 ){
-    yygotominor.yy172->pList = pList;
+  ExprList *pList = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy450, 0);
+  pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy450, 0);
+  yygotominor.yy450 = sqlite3PExpr(pParse, TK_BETWEEN, yymsp[-4].minor.yy450, 0, 0);
+  if( yygotominor.yy450 ){
+    yygotominor.yy450->pList = pList;
   }else{
-    sqlite3ExprListDelete(pList);
+    sqlite3ExprListDelete(pParse->db, pList);
   } 
-  if( yymsp[-3].minor.yy46 ) yygotominor.yy172 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy172, 0, 0);
-  sqlite3ExprSpan(yygotominor.yy172,&yymsp[-4].minor.yy172->span,&yymsp[0].minor.yy172->span);
+  if( yymsp[-3].minor.yy316 ) yygotominor.yy450 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy450, 0, 0);
+  sqlite3ExprSpan(yygotominor.yy450,&yymsp[-4].minor.yy450->span,&yymsp[0].minor.yy450->span);
 }
         break;
-      case 218: /* expr ::= expr in_op LP exprlist RP */
+      case 221: /* expr ::= expr in_op LP exprlist RP */
 {
-    yygotominor.yy172 = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy172, 0, 0);
-    if( yygotominor.yy172 ){
-      yygotominor.yy172->pList = yymsp[-1].minor.yy174;
-      sqlite3ExprSetHeight(yygotominor.yy172);
+    yygotominor.yy450 = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy450, 0, 0);
+    if( yygotominor.yy450 ){
+      yygotominor.yy450->pList = yymsp[-1].minor.yy242;
+      sqlite3ExprSetHeight(pParse, yygotominor.yy450);
     }else{
-      sqlite3ExprListDelete(yymsp[-1].minor.yy174);
+      sqlite3ExprListDelete(pParse->db, yymsp[-1].minor.yy242);
     }
-    if( yymsp[-3].minor.yy46 ) yygotominor.yy172 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy172, 0, 0);
-    sqlite3ExprSpan(yygotominor.yy172,&yymsp[-4].minor.yy172->span,&yymsp[0].minor.yy0);
+    if( yymsp[-3].minor.yy316 ) yygotominor.yy450 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy450, 0, 0);
+    sqlite3ExprSpan(yygotominor.yy450,&yymsp[-4].minor.yy450->span,&yymsp[0].minor.yy0);
   }
         break;
-      case 219: /* expr ::= LP select RP */
+      case 222: /* expr ::= LP select RP */
 {
-    yygotominor.yy172 = sqlite3PExpr(pParse, TK_SELECT, 0, 0, 0);
-    if( yygotominor.yy172 ){
-      yygotominor.yy172->pSelect = yymsp[-1].minor.yy219;
-      sqlite3ExprSetHeight(yygotominor.yy172);
+    yygotominor.yy450 = sqlite3PExpr(pParse, TK_SELECT, 0, 0, 0);
+    if( yygotominor.yy450 ){
+      yygotominor.yy450->pSelect = yymsp[-1].minor.yy43;
+      sqlite3ExprSetHeight(pParse, yygotominor.yy450);
     }else{
-      sqlite3SelectDelete(yymsp[-1].minor.yy219);
+      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy43);
     }
-    sqlite3ExprSpan(yygotominor.yy172,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0);
+    sqlite3ExprSpan(yygotominor.yy450,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0);
   }
         break;
-      case 220: /* expr ::= expr in_op LP select RP */
+      case 223: /* expr ::= expr in_op LP select RP */
 {
-    yygotominor.yy172 = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy172, 0, 0);
-    if( yygotominor.yy172 ){
-      yygotominor.yy172->pSelect = yymsp[-1].minor.yy219;
-      sqlite3ExprSetHeight(yygotominor.yy172);
+    yygotominor.yy450 = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy450, 0, 0);
+    if( yygotominor.yy450 ){
+      yygotominor.yy450->pSelect = yymsp[-1].minor.yy43;
+      sqlite3ExprSetHeight(pParse, yygotominor.yy450);
     }else{
-      sqlite3SelectDelete(yymsp[-1].minor.yy219);
+      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy43);
     }
-    if( yymsp[-3].minor.yy46 ) yygotominor.yy172 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy172, 0, 0);
-    sqlite3ExprSpan(yygotominor.yy172,&yymsp[-4].minor.yy172->span,&yymsp[0].minor.yy0);
+    if( yymsp[-3].minor.yy316 ) yygotominor.yy450 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy450, 0, 0);
+    sqlite3ExprSpan(yygotominor.yy450,&yymsp[-4].minor.yy450->span,&yymsp[0].minor.yy0);
   }
         break;
-      case 221: /* expr ::= expr in_op nm dbnm */
+      case 224: /* expr ::= expr in_op nm dbnm */
 {
-    SrcList *pSrc = sqlite3SrcListAppend(pParse->db, 0,&yymsp[-1].minor.yy410,&yymsp[0].minor.yy410);
-    yygotominor.yy172 = sqlite3PExpr(pParse, TK_IN, yymsp[-3].minor.yy172, 0, 0);
-    if( yygotominor.yy172 ){
-      yygotominor.yy172->pSelect = sqlite3SelectNew(pParse, 0,pSrc,0,0,0,0,0,0,0);
-      sqlite3ExprSetHeight(yygotominor.yy172);
+    SrcList *pSrc = sqlite3SrcListAppend(pParse->db, 0,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0);
+    yygotominor.yy450 = sqlite3PExpr(pParse, TK_IN, yymsp[-3].minor.yy450, 0, 0);
+    if( yygotominor.yy450 ){
+      yygotominor.yy450->pSelect = sqlite3SelectNew(pParse, 0,pSrc,0,0,0,0,0,0,0);
+      sqlite3ExprSetHeight(pParse, yygotominor.yy450);
     }else{
-      sqlite3SrcListDelete(pSrc);
+      sqlite3SrcListDelete(pParse->db, pSrc);
     }
-    if( yymsp[-2].minor.yy46 ) yygotominor.yy172 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy172, 0, 0);
-    sqlite3ExprSpan(yygotominor.yy172,&yymsp[-3].minor.yy172->span,yymsp[0].minor.yy410.z?&yymsp[0].minor.yy410:&yymsp[-1].minor.yy410);
+    if( yymsp[-2].minor.yy316 ) yygotominor.yy450 = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy450, 0, 0);
+    sqlite3ExprSpan(yygotominor.yy450,&yymsp[-3].minor.yy450->span,yymsp[0].minor.yy0.z?&yymsp[0].minor.yy0:&yymsp[-1].minor.yy0);
   }
         break;
-      case 222: /* expr ::= EXISTS LP select RP */
+      case 225: /* expr ::= EXISTS LP select RP */
 {
-    Expr *p = yygotominor.yy172 = sqlite3PExpr(pParse, TK_EXISTS, 0, 0, 0);
+    Expr *p = yygotominor.yy450 = sqlite3PExpr(pParse, TK_EXISTS, 0, 0, 0);
     if( p ){
-      p->pSelect = yymsp[-1].minor.yy219;
+      p->pSelect = yymsp[-1].minor.yy43;
       sqlite3ExprSpan(p,&yymsp[-3].minor.yy0,&yymsp[0].minor.yy0);
-      sqlite3ExprSetHeight(yygotominor.yy172);
+      sqlite3ExprSetHeight(pParse, yygotominor.yy450);
     }else{
-      sqlite3SelectDelete(yymsp[-1].minor.yy219);
+      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy43);
     }
   }
         break;
-      case 223: /* expr ::= CASE case_operand case_exprlist case_else END */
+      case 226: /* expr ::= CASE case_operand case_exprlist case_else END */
 {
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_CASE, yymsp[-3].minor.yy172, yymsp[-1].minor.yy172, 0);
-  if( yygotominor.yy172 ){
-    yygotominor.yy172->pList = yymsp[-2].minor.yy174;
-    sqlite3ExprSetHeight(yygotominor.yy172);
+  yygotominor.yy450 = sqlite3PExpr(pParse, TK_CASE, yymsp[-3].minor.yy450, yymsp[-1].minor.yy450, 0);
+  if( yygotominor.yy450 ){
+    yygotominor.yy450->pList = yymsp[-2].minor.yy242;
+    sqlite3ExprSetHeight(pParse, yygotominor.yy450);
   }else{
-    sqlite3ExprListDelete(yymsp[-2].minor.yy174);
+    sqlite3ExprListDelete(pParse->db, yymsp[-2].minor.yy242);
   }
-  sqlite3ExprSpan(yygotominor.yy172, &yymsp[-4].minor.yy0, &yymsp[0].minor.yy0);
+  sqlite3ExprSpan(yygotominor.yy450, &yymsp[-4].minor.yy0, &yymsp[0].minor.yy0);
 }
         break;
-      case 224: /* case_exprlist ::= case_exprlist WHEN expr THEN expr */
+      case 227: /* case_exprlist ::= case_exprlist WHEN expr THEN expr */
 {
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy174, yymsp[-2].minor.yy172, 0);
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,yygotominor.yy174, yymsp[0].minor.yy172, 0);
+  yygotominor.yy242 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy242, yymsp[-2].minor.yy450, 0);
+  yygotominor.yy242 = sqlite3ExprListAppend(pParse,yygotominor.yy242, yymsp[0].minor.yy450, 0);
 }
         break;
-      case 225: /* case_exprlist ::= WHEN expr THEN expr */
+      case 228: /* case_exprlist ::= WHEN expr THEN expr */
 {
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy172, 0);
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,yygotominor.yy174, yymsp[0].minor.yy172, 0);
+  yygotominor.yy242 = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy450, 0);
+  yygotominor.yy242 = sqlite3ExprListAppend(pParse,yygotominor.yy242, yymsp[0].minor.yy450, 0);
 }
         break;
-      case 234: /* cmd ::= CREATE uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP */
+      case 237: /* cmd ::= CREATE uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP */
 {
-  sqlite3CreateIndex(pParse, &yymsp[-6].minor.yy410, &yymsp[-5].minor.yy410, 
-                     sqlite3SrcListAppend(pParse->db,0,&yymsp[-3].minor.yy410,0), yymsp[-1].minor.yy174, yymsp[-9].minor.yy46,
-                      &yymsp[-10].minor.yy0, &yymsp[0].minor.yy0, SQLITE_SO_ASC, yymsp[-7].minor.yy46);
+  sqlite3CreateIndex(pParse, &yymsp[-6].minor.yy0, &yymsp[-5].minor.yy0, 
+                     sqlite3SrcListAppend(pParse->db,0,&yymsp[-3].minor.yy0,0), yymsp[-1].minor.yy242, yymsp[-9].minor.yy316,
+                      &yymsp[-10].minor.yy0, &yymsp[0].minor.yy0, SQLITE_SO_ASC, yymsp[-7].minor.yy316);
 }
         break;
-      case 235: /* uniqueflag ::= UNIQUE */
-      case 282: /* raisetype ::= ABORT */
-{yygotominor.yy46 = OE_Abort;}
+      case 238: /* uniqueflag ::= UNIQUE */
+      case 285: /* raisetype ::= ABORT */
+{yygotominor.yy316 = OE_Abort;}
         break;
-      case 236: /* uniqueflag ::= */
-{yygotominor.yy46 = OE_None;}
+      case 239: /* uniqueflag ::= */
+{yygotominor.yy316 = OE_None;}
         break;
-      case 239: /* idxlist ::= idxlist COMMA idxitem collate sortorder */
+      case 242: /* idxlist ::= idxlist COMMA nm collate sortorder */
 {
   Expr *p = 0;
-  if( yymsp[-1].minor.yy410.n>0 ){
+  if( yymsp[-1].minor.yy0.n>0 ){
     p = sqlite3PExpr(pParse, TK_COLUMN, 0, 0, 0);
-    sqlite3ExprSetColl(pParse, p, &yymsp[-1].minor.yy410);
+    sqlite3ExprSetColl(pParse, p, &yymsp[-1].minor.yy0);
   }
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy174, p, &yymsp[-2].minor.yy410);
-  sqlite3ExprListCheckLength(pParse, yygotominor.yy174, SQLITE_MAX_COLUMN, "index");
-  if( yygotominor.yy174 ) yygotominor.yy174->a[yygotominor.yy174->nExpr-1].sortOrder = yymsp[0].minor.yy46;
+  yygotominor.yy242 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy242, p, &yymsp[-2].minor.yy0);
+  sqlite3ExprListCheckLength(pParse, yygotominor.yy242, "index");
+  if( yygotominor.yy242 ) yygotominor.yy242->a[yygotominor.yy242->nExpr-1].sortOrder = yymsp[0].minor.yy316;
 }
         break;
-      case 240: /* idxlist ::= idxitem collate sortorder */
+      case 243: /* idxlist ::= nm collate sortorder */
 {
   Expr *p = 0;
-  if( yymsp[-1].minor.yy410.n>0 ){
+  if( yymsp[-1].minor.yy0.n>0 ){
     p = sqlite3PExpr(pParse, TK_COLUMN, 0, 0, 0);
-    sqlite3ExprSetColl(pParse, p, &yymsp[-1].minor.yy410);
+    sqlite3ExprSetColl(pParse, p, &yymsp[-1].minor.yy0);
   }
-  yygotominor.yy174 = sqlite3ExprListAppend(pParse,0, p, &yymsp[-2].minor.yy410);
-  sqlite3ExprListCheckLength(pParse, yygotominor.yy174, SQLITE_MAX_COLUMN, "index");
-  if( yygotominor.yy174 ) yygotominor.yy174->a[yygotominor.yy174->nExpr-1].sortOrder = yymsp[0].minor.yy46;
+  yygotominor.yy242 = sqlite3ExprListAppend(pParse,0, p, &yymsp[-2].minor.yy0);
+  sqlite3ExprListCheckLength(pParse, yygotominor.yy242, "index");
+  if( yygotominor.yy242 ) yygotominor.yy242->a[yygotominor.yy242->nExpr-1].sortOrder = yymsp[0].minor.yy316;
 }
         break;
-      case 242: /* collate ::= */
-{yygotominor.yy410.z = 0; yygotominor.yy410.n = 0;}
+      case 244: /* collate ::= */
+{yygotominor.yy0.z = 0; yygotominor.yy0.n = 0;}
         break;
-      case 244: /* cmd ::= DROP INDEX ifexists fullname */
-{sqlite3DropIndex(pParse, yymsp[0].minor.yy373, yymsp[-1].minor.yy46);}
+      case 246: /* cmd ::= DROP INDEX ifexists fullname */
+{sqlite3DropIndex(pParse, yymsp[0].minor.yy419, yymsp[-1].minor.yy316);}
         break;
-      case 245: /* cmd ::= VACUUM */
-      case 246: /* cmd ::= VACUUM nm */
+      case 247: /* cmd ::= VACUUM */
+      case 248: /* cmd ::= VACUUM nm */
 {sqlite3Vacuum(pParse);}
         break;
-      case 247: /* cmd ::= PRAGMA nm dbnm EQ nmnum */
-{sqlite3Pragma(pParse,&yymsp[-3].minor.yy410,&yymsp[-2].minor.yy410,&yymsp[0].minor.yy410,0);}
-        break;
-      case 248: /* cmd ::= PRAGMA nm dbnm EQ ON */
-{sqlite3Pragma(pParse,&yymsp[-3].minor.yy410,&yymsp[-2].minor.yy410,&yymsp[0].minor.yy0,0);}
+      case 249: /* cmd ::= PRAGMA nm dbnm EQ nmnum */
+      case 250: /* cmd ::= PRAGMA nm dbnm EQ ON */
+      case 251: /* cmd ::= PRAGMA nm dbnm EQ DELETE */
+{sqlite3Pragma(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0,0);}
         break;
-      case 249: /* cmd ::= PRAGMA nm dbnm EQ minus_num */
+      case 252: /* cmd ::= PRAGMA nm dbnm EQ minus_num */
 {
-  sqlite3Pragma(pParse,&yymsp[-3].minor.yy410,&yymsp[-2].minor.yy410,&yymsp[0].minor.yy410,1);
+  sqlite3Pragma(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0,1);
 }
         break;
-      case 250: /* cmd ::= PRAGMA nm dbnm LP nmnum RP */
-{sqlite3Pragma(pParse,&yymsp[-4].minor.yy410,&yymsp[-3].minor.yy410,&yymsp[-1].minor.yy410,0);}
+      case 253: /* cmd ::= PRAGMA nm dbnm LP nmnum RP */
+{sqlite3Pragma(pParse,&yymsp[-4].minor.yy0,&yymsp[-3].minor.yy0,&yymsp[-1].minor.yy0,0);}
         break;
-      case 251: /* cmd ::= PRAGMA nm dbnm */
-{sqlite3Pragma(pParse,&yymsp[-1].minor.yy410,&yymsp[0].minor.yy410,0,0);}
+      case 254: /* cmd ::= PRAGMA nm dbnm */
+{sqlite3Pragma(pParse,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0,0,0);}
         break;
-      case 259: /* cmd ::= CREATE trigger_decl BEGIN trigger_cmd_list END */
+      case 262: /* cmd ::= CREATE trigger_decl BEGIN trigger_cmd_list END */
 {
   Token all;
-  all.z = yymsp[-3].minor.yy410.z;
-  all.n = (yymsp[0].minor.yy0.z - yymsp[-3].minor.yy410.z) + yymsp[0].minor.yy0.n;
-  sqlite3FinishTrigger(pParse, yymsp[-1].minor.yy243, &all);
+  all.z = yymsp[-3].minor.yy0.z;
+  all.n = (yymsp[0].minor.yy0.z - yymsp[-3].minor.yy0.z) + yymsp[0].minor.yy0.n;
+  sqlite3FinishTrigger(pParse, yymsp[-1].minor.yy75, &all);
 }
         break;
-      case 260: /* trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause */
+      case 263: /* trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause */
 {
-  sqlite3BeginTrigger(pParse, &yymsp[-7].minor.yy410, &yymsp[-6].minor.yy410, yymsp[-5].minor.yy46, yymsp[-4].minor.yy370.a, yymsp[-4].minor.yy370.b, yymsp[-2].minor.yy373, yymsp[0].minor.yy172, yymsp[-10].minor.yy46, yymsp[-8].minor.yy46);
-  yygotominor.yy410 = (yymsp[-6].minor.yy410.n==0?yymsp[-7].minor.yy410:yymsp[-6].minor.yy410);
+  sqlite3BeginTrigger(pParse, &yymsp[-7].minor.yy0, &yymsp[-6].minor.yy0, yymsp[-5].minor.yy316, yymsp[-4].minor.yy354.a, yymsp[-4].minor.yy354.b, yymsp[-2].minor.yy419, yymsp[0].minor.yy450, yymsp[-10].minor.yy316, yymsp[-8].minor.yy316);
+  yygotominor.yy0 = (yymsp[-6].minor.yy0.n==0?yymsp[-7].minor.yy0:yymsp[-6].minor.yy0);
 }
         break;
-      case 261: /* trigger_time ::= BEFORE */
-      case 264: /* trigger_time ::= */
-{ yygotominor.yy46 = TK_BEFORE; }
+      case 264: /* trigger_time ::= BEFORE */
+      case 267: /* trigger_time ::= */
+{ yygotominor.yy316 = TK_BEFORE; }
         break;
-      case 262: /* trigger_time ::= AFTER */
-{ yygotominor.yy46 = TK_AFTER;  }
+      case 265: /* trigger_time ::= AFTER */
+{ yygotominor.yy316 = TK_AFTER;  }
         break;
-      case 263: /* trigger_time ::= INSTEAD OF */
-{ yygotominor.yy46 = TK_INSTEAD;}
+      case 266: /* trigger_time ::= INSTEAD OF */
+{ yygotominor.yy316 = TK_INSTEAD;}
         break;
-      case 265: /* trigger_event ::= DELETE|INSERT */
-      case 266: /* trigger_event ::= UPDATE */
-{yygotominor.yy370.a = yymsp[0].major; yygotominor.yy370.b = 0;}
+      case 268: /* trigger_event ::= DELETE|INSERT */
+      case 269: /* trigger_event ::= UPDATE */
+{yygotominor.yy354.a = yymsp[0].major; yygotominor.yy354.b = 0;}
         break;
-      case 267: /* trigger_event ::= UPDATE OF inscollist */
-{yygotominor.yy370.a = TK_UPDATE; yygotominor.yy370.b = yymsp[0].minor.yy432;}
+      case 270: /* trigger_event ::= UPDATE OF inscollist */
+{yygotominor.yy354.a = TK_UPDATE; yygotominor.yy354.b = yymsp[0].minor.yy352;}
         break;
-      case 270: /* when_clause ::= */
-      case 287: /* key_opt ::= */
-{ yygotominor.yy172 = 0; }
+      case 273: /* when_clause ::= */
+      case 290: /* key_opt ::= */
+{ yygotominor.yy450 = 0; }
         break;
-      case 271: /* when_clause ::= WHEN expr */
-      case 288: /* key_opt ::= KEY expr */
-{ yygotominor.yy172 = yymsp[0].minor.yy172; }
+      case 274: /* when_clause ::= WHEN expr */
+      case 291: /* key_opt ::= KEY expr */
+{ yygotominor.yy450 = yymsp[0].minor.yy450; }
         break;
-      case 272: /* trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI */
+      case 275: /* trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI */
 {
-  if( yymsp[-2].minor.yy243 ){
-    yymsp[-2].minor.yy243->pLast->pNext = yymsp[-1].minor.yy243;
+/*
+  if( yymsp[-2].minor.yy75 ){
+    yymsp[-2].minor.yy75->pLast->pNext = yymsp[-1].minor.yy75;
   }else{
-    yymsp[-2].minor.yy243 = yymsp[-1].minor.yy243;
+    yymsp[-2].minor.yy75 = yymsp[-1].minor.yy75;
   }
-  yymsp[-2].minor.yy243->pLast = yymsp[-1].minor.yy243;
-  yygotominor.yy243 = yymsp[-2].minor.yy243;
+*/
+  assert( yymsp[-2].minor.yy75!=0 );
+  yymsp[-2].minor.yy75->pLast->pNext = yymsp[-1].minor.yy75;
+  yymsp[-2].minor.yy75->pLast = yymsp[-1].minor.yy75;
+  yygotominor.yy75 = yymsp[-2].minor.yy75;
 }
         break;
-      case 273: /* trigger_cmd_list ::= */
-{ yygotominor.yy243 = 0; }
+      case 276: /* trigger_cmd_list ::= trigger_cmd SEMI */
+{ 
+  /* if( yymsp[-1].minor.yy75 ) */
+  assert( yymsp[-1].minor.yy75!=0 );
+  yymsp[-1].minor.yy75->pLast = yymsp[-1].minor.yy75;
+  yygotominor.yy75 = yymsp[-1].minor.yy75;
+}
         break;
-      case 274: /* trigger_cmd ::= UPDATE orconf nm SET setlist where_opt */
-{ yygotominor.yy243 = sqlite3TriggerUpdateStep(pParse->db, &yymsp[-3].minor.yy410, yymsp[-1].minor.yy174, yymsp[0].minor.yy172, yymsp[-4].minor.yy46); }
+      case 277: /* trigger_cmd ::= UPDATE orconf nm SET setlist where_opt */
+{ yygotominor.yy75 = sqlite3TriggerUpdateStep(pParse->db, &yymsp[-3].minor.yy0, yymsp[-1].minor.yy242, yymsp[0].minor.yy450, yymsp[-4].minor.yy316); }
         break;
-      case 275: /* trigger_cmd ::= insert_cmd INTO nm inscollist_opt VALUES LP itemlist RP */
-{yygotominor.yy243 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-5].minor.yy410, yymsp[-4].minor.yy432, yymsp[-1].minor.yy174, 0, yymsp[-7].minor.yy46);}
+      case 278: /* trigger_cmd ::= insert_cmd INTO nm inscollist_opt VALUES LP itemlist RP */
+{yygotominor.yy75 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-5].minor.yy0, yymsp[-4].minor.yy352, yymsp[-1].minor.yy242, 0, yymsp[-7].minor.yy316);}
         break;
-      case 276: /* trigger_cmd ::= insert_cmd INTO nm inscollist_opt select */
-{yygotominor.yy243 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-2].minor.yy410, yymsp[-1].minor.yy432, 0, yymsp[0].minor.yy219, yymsp[-4].minor.yy46);}
+      case 279: /* trigger_cmd ::= insert_cmd INTO nm inscollist_opt select */
+{yygotominor.yy75 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-2].minor.yy0, yymsp[-1].minor.yy352, 0, yymsp[0].minor.yy43, yymsp[-4].minor.yy316);}
         break;
-      case 277: /* trigger_cmd ::= DELETE FROM nm where_opt */
-{yygotominor.yy243 = sqlite3TriggerDeleteStep(pParse->db, &yymsp[-1].minor.yy410, yymsp[0].minor.yy172);}
+      case 280: /* trigger_cmd ::= DELETE FROM nm where_opt */
+{yygotominor.yy75 = sqlite3TriggerDeleteStep(pParse->db, &yymsp[-1].minor.yy0, yymsp[0].minor.yy450);}
         break;
-      case 278: /* trigger_cmd ::= select */
-{yygotominor.yy243 = sqlite3TriggerSelectStep(pParse->db, yymsp[0].minor.yy219); }
+      case 281: /* trigger_cmd ::= select */
+{yygotominor.yy75 = sqlite3TriggerSelectStep(pParse->db, yymsp[0].minor.yy43); }
         break;
-      case 279: /* expr ::= RAISE LP IGNORE RP */
+      case 282: /* expr ::= RAISE LP IGNORE RP */
 {
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_RAISE, 0, 0, 0); 
-  if( yygotominor.yy172 ){
-    yygotominor.yy172->iColumn = OE_Ignore;
-    sqlite3ExprSpan(yygotominor.yy172, &yymsp[-3].minor.yy0, &yymsp[0].minor.yy0);
+  yygotominor.yy450 = sqlite3PExpr(pParse, TK_RAISE, 0, 0, 0); 
+  if( yygotominor.yy450 ){
+    yygotominor.yy450->iColumn = OE_Ignore;
+    sqlite3ExprSpan(yygotominor.yy450, &yymsp[-3].minor.yy0, &yymsp[0].minor.yy0);
   }
 }
         break;
-      case 280: /* expr ::= RAISE LP raisetype COMMA nm RP */
+      case 283: /* expr ::= RAISE LP raisetype COMMA nm RP */
 {
-  yygotominor.yy172 = sqlite3PExpr(pParse, TK_RAISE, 0, 0, &yymsp[-1].minor.yy410); 
-  if( yygotominor.yy172 ) {
-    yygotominor.yy172->iColumn = yymsp[-3].minor.yy46;
-    sqlite3ExprSpan(yygotominor.yy172, &yymsp[-5].minor.yy0, &yymsp[0].minor.yy0);
+  yygotominor.yy450 = sqlite3PExpr(pParse, TK_RAISE, 0, 0, &yymsp[-1].minor.yy0); 
+  if( yygotominor.yy450 ) {
+    yygotominor.yy450->iColumn = yymsp[-3].minor.yy316;
+    sqlite3ExprSpan(yygotominor.yy450, &yymsp[-5].minor.yy0, &yymsp[0].minor.yy0);
   }
 }
         break;
-      case 281: /* raisetype ::= ROLLBACK */
-{yygotominor.yy46 = OE_Rollback;}
+      case 284: /* raisetype ::= ROLLBACK */
+{yygotominor.yy316 = OE_Rollback;}
         break;
-      case 283: /* raisetype ::= FAIL */
-{yygotominor.yy46 = OE_Fail;}
+      case 286: /* raisetype ::= FAIL */
+{yygotominor.yy316 = OE_Fail;}
         break;
-      case 284: /* cmd ::= DROP TRIGGER ifexists fullname */
+      case 287: /* cmd ::= DROP TRIGGER ifexists fullname */
 {
-  sqlite3DropTrigger(pParse,yymsp[0].minor.yy373,yymsp[-1].minor.yy46);
+  sqlite3DropTrigger(pParse,yymsp[0].minor.yy419,yymsp[-1].minor.yy316);
 }
         break;
-      case 285: /* cmd ::= ATTACH database_kw_opt expr AS expr key_opt */
+      case 288: /* cmd ::= ATTACH database_kw_opt expr AS expr key_opt */
 {
-  sqlite3Attach(pParse, yymsp[-3].minor.yy172, yymsp[-1].minor.yy172, yymsp[0].minor.yy172);
+  sqlite3Attach(pParse, yymsp[-3].minor.yy450, yymsp[-1].minor.yy450, yymsp[0].minor.yy450);
 }
         break;
-      case 286: /* cmd ::= DETACH database_kw_opt expr */
+      case 289: /* cmd ::= DETACH database_kw_opt expr */
 {
-  sqlite3Detach(pParse, yymsp[0].minor.yy172);
+  sqlite3Detach(pParse, yymsp[0].minor.yy450);
 }
         break;
-      case 291: /* cmd ::= REINDEX */
+      case 294: /* cmd ::= REINDEX */
 {sqlite3Reindex(pParse, 0, 0);}
         break;
-      case 292: /* cmd ::= REINDEX nm dbnm */
-{sqlite3Reindex(pParse, &yymsp[-1].minor.yy410, &yymsp[0].minor.yy410);}
+      case 295: /* cmd ::= REINDEX nm dbnm */
+{sqlite3Reindex(pParse, &yymsp[-1].minor.yy0, &yymsp[0].minor.yy0);}
         break;
-      case 293: /* cmd ::= ANALYZE */
+      case 296: /* cmd ::= ANALYZE */
 {sqlite3Analyze(pParse, 0, 0);}
         break;
-      case 294: /* cmd ::= ANALYZE nm dbnm */
-{sqlite3Analyze(pParse, &yymsp[-1].minor.yy410, &yymsp[0].minor.yy410);}
+      case 297: /* cmd ::= ANALYZE nm dbnm */
+{sqlite3Analyze(pParse, &yymsp[-1].minor.yy0, &yymsp[0].minor.yy0);}
         break;
-      case 295: /* cmd ::= ALTER TABLE fullname RENAME TO nm */
+      case 298: /* cmd ::= ALTER TABLE fullname RENAME TO nm */
 {
-  sqlite3AlterRenameTable(pParse,yymsp[-3].minor.yy373,&yymsp[0].minor.yy410);
+  sqlite3AlterRenameTable(pParse,yymsp[-3].minor.yy419,&yymsp[0].minor.yy0);
 }
         break;
-      case 296: /* cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column */
+      case 299: /* cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column */
 {
-  sqlite3AlterFinishAddColumn(pParse, &yymsp[0].minor.yy410);
+  sqlite3AlterFinishAddColumn(pParse, &yymsp[0].minor.yy0);
 }
         break;
-      case 297: /* add_column_fullname ::= fullname */
+      case 300: /* add_column_fullname ::= fullname */
 {
-  sqlite3AlterBeginAddColumn(pParse, yymsp[0].minor.yy373);
+  sqlite3AlterBeginAddColumn(pParse, yymsp[0].minor.yy419);
 }
         break;
-      case 300: /* cmd ::= create_vtab */
+      case 303: /* cmd ::= create_vtab */
 {sqlite3VtabFinishParse(pParse,0);}
         break;
-      case 301: /* cmd ::= create_vtab LP vtabarglist RP */
+      case 304: /* cmd ::= create_vtab LP vtabarglist RP */
 {sqlite3VtabFinishParse(pParse,&yymsp[0].minor.yy0);}
         break;
-      case 302: /* create_vtab ::= CREATE VIRTUAL TABLE nm dbnm USING nm */
+      case 305: /* create_vtab ::= CREATE VIRTUAL TABLE nm dbnm USING nm */
 {
-    sqlite3VtabBeginParse(pParse, &yymsp[-3].minor.yy410, &yymsp[-2].minor.yy410, &yymsp[0].minor.yy410);
+    sqlite3VtabBeginParse(pParse, &yymsp[-3].minor.yy0, &yymsp[-2].minor.yy0, &yymsp[0].minor.yy0);
 }
         break;
-      case 305: /* vtabarg ::= */
+      case 308: /* vtabarg ::= */
 {sqlite3VtabArgInit(pParse);}
         break;
-      case 307: /* vtabargtoken ::= ANY */
-      case 308: /* vtabargtoken ::= lp anylist RP */
-      case 309: /* lp ::= LP */
-      case 311: /* anylist ::= anylist ANY */
+      case 310: /* vtabargtoken ::= ANY */
+      case 311: /* vtabargtoken ::= lp anylist RP */
+      case 312: /* lp ::= LP */
+      case 314: /* anylist ::= anylist ANY */
 {sqlite3VtabArgExtend(pParse,&yymsp[0].minor.yy0);}
         break;
   };
@@ -73709,7 +81871,8 @@ SQLITE_PRIVATE void sqlite3Parser(
   if( yypParser->yyidx<0 ){
 #if YYSTACKDEPTH<=0
     if( yypParser->yystksz <=0 ){
-      memset(&yyminorunion, 0, sizeof(yyminorunion));
+      /*memset(&yyminorunion, 0, sizeof(yyminorunion));*/
+      yyminorunion = yyzerominor;
       yyStackOverflow(yypParser, &yyminorunion);
       return;
     }
@@ -73779,7 +81942,7 @@ SQLITE_PRIVATE void sqlite3Parser(
              yyTracePrompt,yyTokenName[yymajor]);
         }
 #endif
-        yy_destructor(yymajor,&yyminorunion);
+        yy_destructor(yypParser, yymajor,&yyminorunion);
         yymajor = YYNOCODE;
       }else{
          while(
@@ -73792,7 +81955,7 @@ SQLITE_PRIVATE void sqlite3Parser(
           yy_pop_parser_stack(yypParser);
         }
         if( yypParser->yyidx < 0 || yymajor==0 ){
-          yy_destructor(yymajor,&yyminorunion);
+          yy_destructor(yypParser,yymajor,&yyminorunion);
           yy_parse_failed(yypParser);
           yymajor = YYNOCODE;
         }else if( yymx!=YYERRORSYMBOL ){
@@ -73817,7 +81980,7 @@ SQLITE_PRIVATE void sqlite3Parser(
         yy_syntax_error(yypParser,yymajor,yyminorunion);
       }
       yypParser->yyerrcnt = 3;
-      yy_destructor(yymajor,&yyminorunion);
+      yy_destructor(yypParser,yymajor,&yyminorunion);
       if( yyendofinput ){
         yy_parse_failed(yypParser);
       }
@@ -73847,7 +82010,7 @@ SQLITE_PRIVATE void sqlite3Parser(
 ** individual tokens and sends those tokens one-by-one over to the
 ** parser for analysis.
 **
-** $Id: tokenize.c,v 1.138 2008/01/22 23:37:10 drh Exp $
+** $Id: tokenize.c,v 1.152 2008/09/01 15:52:11 drh Exp $
 */
 
 /*
@@ -73900,7 +82063,7 @@ const unsigned char ebcdicToAscii[] = {
 **
 ** The code in this file has been automatically generated by
 **
-**     $Header: /sqlite/sqlite/tool/mkkeywordhash.c,v 1.31 2007/07/30 18:26:20 rse Exp $
+**     $Header: /sqlite/sqlite/tool/mkkeywordhash.c,v 1.32 2008/10/06 05:32:19 danielk1977 Exp $
 **
 ** The code in this file implements a function that determines whether
 ** or not a given identifier is really an SQL keyword.  The same thing
@@ -73909,89 +82072,89 @@ const unsigned char ebcdicToAscii[] = {
 ** is substantially reduced.  This is important for embedded applications
 ** on platforms with limited memory.
 */
-/* Hash score: 165 */
+/* Hash score: 167 */
 static int keywordCode(const char *z, int n){
-  /* zText[] encodes 775 bytes of keywords in 526 bytes */
-  static const char zText[526] =
-    "BEFOREIGNOREGEXPLAINSTEADDESCAPEACHECKEYCONSTRAINTERSECTABLEFT"
-    "HENDATABASELECTRANSACTIONATURALTERAISELSEXCEPTRIGGEREFERENCES"
-    "UNIQUERYATTACHAVINGROUPDATEMPORARYBEGINNEREINDEXCLUSIVEXISTSBETWEEN"
-    "OTNULLIKECASCADEFERRABLECASECOLLATECREATECURRENT_DATEDELETEDETACH"
-    "IMMEDIATEJOINSERTMATCHPLANALYZEPRAGMABORTVALUESVIRTUALIMITWHEN"
-    "WHERENAMEAFTEREPLACEANDEFAULTAUTOINCREMENTCASTCOLUMNCOMMITCONFLICT"
-    "CROSSCURRENT_TIMESTAMPRIMARYDEFERREDISTINCTDROPFAILFROMFULLGLOB"
-    "YIFINTOFFSETISNULLORDERESTRICTOUTERIGHTROLLBACKROWUNIONUSINGVACUUM"
+  /* zText[] encodes 783 bytes of keywords in 528 bytes */
+  static const char zText[528] =
+    "REINDEXEDESCAPEACHECKEYBEFOREIGNOREGEXPLAINSTEADDATABASELECTABLE"
+    "FTHENDEFERRABLELSEXCEPTRANSACTIONATURALTERAISEXCLUSIVEXISTSCONSTRAINT"
+    "ERSECTRIGGEREFERENCESUNIQUERYATTACHAVINGROUPDATEMPORARYBEGINNER"
+    "ENAMEBETWEENOTNULLIKECASCADELETECASECOLLATECREATECURRENT_DATE"
+    "DETACHIMMEDIATEJOINSERTMATCHPLANALYZEPRAGMABORTVALUESVIRTUALIMIT"
+    "WHENWHEREPLACEAFTERESTRICTANDEFAULTAUTOINCREMENTCASTCOLUMNCOMMIT"
+    "CONFLICTCROSSCURRENT_TIMESTAMPRIMARYDEFERREDISTINCTDROPFAILFROM"
+    "FULLGLOBYIFINTOFFSETISNULLORDERIGHTOUTEROLLBACKROWUNIONUSINGVACUUM"
     "VIEWINITIALLY";
   static const unsigned char aHash[127] = {
-      63,  92, 109,  61,   0,  38,   0,   0,  69,   0,  64,   0,   0,
-     102,   4,  65,   7,   0, 108,  72, 103,  99,   0,  22,   0,   0,
-     113,   0, 111, 106,   0,  18,  80,   0,   1,   0,   0,  56,  57,
-       0,  55,  11,   0,  33,  77,  89,   0, 110,  88,   0,   0,  45,
-       0,  90,  54,   0,  20,   0, 114,  34,  19,   0,  10,  97,  28,
-      83,   0,   0, 116,  93,  47, 115,  41,  12,  44,   0,  78,   0,
-      87,  29,   0,  86,   0,   0,   0,  82,  79,  84,  75,  96,   6,
-      14,  95,   0,  68,   0,  21,  76,  98,  27,   0, 112,  67, 104,
-      49,  40,  71,   0,   0,  81, 100,   0, 107,   0,  15,   0,   0,
-      24,   0,  73,  42,  50,   0,  16,  48,   0,  37,
+      65,  94, 110,  63,   0,  44,   0,   0,  71,   0,  66,   0,   0,
+     104,  12,  67,  15,   0, 108,  74, 105, 101,   0,  19,   0,   0,
+     114,   0, 112,  78,   0,  22,  82,   0,   9,   0,   0,  59,  60,
+       0,  58,   6,   0,  39,  79,  91,   0, 111,  90,   0,   0,  45,
+       0,  92,  24,   0,  17,   0, 115,  40,  23,   0,   5,  99,  25,
+      85,   0,   0, 117,  95,  50, 116,  47,   7,  42,   0,  80,   0,
+      89,  26,   0,  88,   0,   0,   0,  84,  81,  86,  77,  98,  14,
+      34,  97,   0,  70,   0,  18,  76, 100,  31,   0, 113,  69, 106,
+      52,  46,  73,   0,   0,  83, 102,   0, 109,   0,  35,   0,   0,
+      28,   0,  75,  48,  53,   0,  20,  51,   0,  43,
   };
-  static const unsigned char aNext[116] = {
-       0,   0,   0,   0,   0,   0,   0,   0,   0,   9,   0,   0,   0,
-       0,   0,   0,   0,   5,   0,   0,   0,   0,   0,   0,   0,   0,
-       0,   0,   0,   0,   0,   0,   0,   0,   0,   0,  32,   0,   0,
-      17,   0,   0,   0,  36,  39,   0,   0,  25,   0,   0,  31,   0,
-       0,   0,  43,  52,   0,   0,   0,  53,   0,   0,   0,   0,   0,
-       0,   0,   0,   0,  51,   0,   0,   0,   0,  26,   0,   8,  46,
-       2,   0,   0,   0,   0,   0,   0,   0,   3,  58,  66,   0,  13,
-       0,  91,  85,   0,  94,   0,  74,   0,   0,  62,   0,  35, 101,
-       0,   0, 105,  23,  30,  60,  70,   0,   0,  59,   0,   0,
+  static const unsigned char aNext[117] = {
+       0,   0,   0,   0,   4,   0,   0,   0,   0,   0,   0,   0,   0,
+       0,   2,   0,   0,   0,   0,   0,   0,  13,   0,   0,   0,   0,
+       0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+       0,   0,   3,  38,   0,  32,  21,   0,   0,   0,   0,  29,   0,
+       0,  37,   0,   0,   0,   1,  55,   0,   0,  56,   0,   0,   0,
+       0,   0,   0,   0,   0,   0,  54,   0,   0,   0,   0,  30,   0,
+      16,  33,  10,   0,   0,   0,   0,   0,   0,   0,  11,  61,  68,
+       0,   8,   0,  93,  87,   0,  96,   0,  49,   0,   0,  64,   0,
+      41, 103,   0,  27, 107,  36,  62,  72,   0,   0,  57,   0,   0,
   };
-  static const unsigned char aLen[116] = {
-       6,   7,   3,   6,   6,   7,   7,   3,   4,   6,   4,   5,   3,
-      10,   9,   5,   4,   4,   3,   8,   2,   6,  11,   2,   7,   5,
-       5,   4,   6,   7,  10,   6,   5,   6,   6,   5,   6,   4,   9,
-       2,   5,   5,   7,   5,   9,   6,   7,   7,   3,   4,   4,   7,
-       3,  10,   4,   7,   6,  12,   6,   6,   9,   4,   6,   5,   4,
-       7,   6,   5,   6,   7,   5,   4,   5,   6,   5,   7,   3,   7,
-      13,   2,   2,   4,   6,   6,   8,   5,  17,  12,   7,   8,   8,
-       2,   4,   4,   4,   4,   4,   2,   2,   4,   6,   2,   3,   6,
-       5,   8,   5,   5,   8,   3,   5,   5,   6,   4,   9,   3,
+  static const unsigned char aLen[117] = {
+       7,   7,   5,   4,   6,   4,   5,   3,   6,   7,   3,   6,   6,
+       7,   7,   3,   8,   2,   6,   5,   4,   4,   3,  10,   4,   6,
+      11,   2,   7,   5,   5,   9,   6,  10,   9,   7,  10,   6,   5,
+       6,   6,   5,   6,   4,   9,   2,   5,   5,   6,   7,   7,   3,
+       4,   4,   7,   3,   6,   4,   7,   6,  12,   6,   9,   4,   6,
+       5,   4,   7,   6,   5,   6,   7,   5,   4,   5,   7,   5,   8,
+       3,   7,  13,   2,   2,   4,   6,   6,   8,   5,  17,  12,   7,
+       8,   8,   2,   4,   4,   4,   4,   4,   2,   2,   4,   6,   2,
+       3,   6,   5,   5,   5,   8,   3,   5,   5,   6,   4,   9,   3,
   };
-  static const unsigned short int aOffset[116] = {
-       0,   2,   2,   6,  10,  13,  18,  23,  25,  26,  31,  33,  37,
-      40,  47,  55,  58,  61,  63,  65,  70,  71,  76,  85,  86,  91,
-      95,  99, 102, 107, 113, 123, 126, 131, 136, 141, 144, 148, 148,
-     152, 157, 160, 164, 166, 169, 177, 183, 189, 189, 192, 195, 199,
-     200, 204, 214, 218, 225, 231, 243, 249, 255, 264, 266, 272, 277,
-     279, 286, 291, 296, 302, 308, 313, 317, 320, 326, 330, 337, 339,
-     346, 348, 350, 359, 363, 369, 375, 383, 388, 388, 404, 411, 418,
-     419, 426, 430, 434, 438, 442, 445, 447, 449, 452, 452, 455, 458,
-     464, 468, 476, 480, 485, 493, 496, 501, 506, 512, 516, 521,
+  static const unsigned short int aOffset[117] = {
+       0,   2,   2,   8,   9,  14,  16,  20,  23,  25,  25,  29,  33,
+      36,  41,  46,  48,  53,  54,  59,  62,  65,  67,  69,  78,  81,
+      86,  95,  96, 101, 105, 109, 117, 123, 130, 138, 144, 154, 157,
+     162, 167, 172, 175, 179, 179, 183, 188, 191, 195, 201, 207, 207,
+     210, 213, 217, 218, 222, 228, 232, 239, 245, 257, 263, 272, 274,
+     280, 285, 287, 294, 299, 304, 310, 316, 321, 325, 328, 335, 339,
+     347, 349, 356, 358, 360, 369, 373, 379, 385, 393, 398, 398, 414,
+     421, 428, 429, 436, 440, 444, 448, 452, 455, 457, 459, 462, 462,
+     465, 468, 474, 478, 483, 487, 495, 498, 503, 508, 514, 518, 523,
   };
-  static const unsigned char aCode[116] = {
-    TK_BEFORE,     TK_FOREIGN,    TK_FOR,        TK_IGNORE,     TK_LIKE_KW,    
-    TK_EXPLAIN,    TK_INSTEAD,    TK_ADD,        TK_DESC,       TK_ESCAPE,     
-    TK_EACH,       TK_CHECK,      TK_KEY,        TK_CONSTRAINT, TK_INTERSECT,  
-    TK_TABLE,      TK_JOIN_KW,    TK_THEN,       TK_END,        TK_DATABASE,   
-    TK_AS,         TK_SELECT,     TK_TRANSACTION,TK_ON,         TK_JOIN_KW,    
-    TK_ALTER,      TK_RAISE,      TK_ELSE,       TK_EXCEPT,     TK_TRIGGER,    
-    TK_REFERENCES, TK_UNIQUE,     TK_QUERY,      TK_ATTACH,     TK_HAVING,     
-    TK_GROUP,      TK_UPDATE,     TK_TEMP,       TK_TEMP,       TK_OR,         
-    TK_BEGIN,      TK_JOIN_KW,    TK_REINDEX,    TK_INDEX,      TK_EXCLUSIVE,  
-    TK_EXISTS,     TK_BETWEEN,    TK_NOTNULL,    TK_NOT,        TK_NULL,       
-    TK_LIKE_KW,    TK_CASCADE,    TK_ASC,        TK_DEFERRABLE, TK_CASE,       
-    TK_COLLATE,    TK_CREATE,     TK_CTIME_KW,   TK_DELETE,     TK_DETACH,     
-    TK_IMMEDIATE,  TK_JOIN,       TK_INSERT,     TK_MATCH,      TK_PLAN,       
-    TK_ANALYZE,    TK_PRAGMA,     TK_ABORT,      TK_VALUES,     TK_VIRTUAL,    
-    TK_LIMIT,      TK_WHEN,       TK_WHERE,      TK_RENAME,     TK_AFTER,      
-    TK_REPLACE,    TK_AND,        TK_DEFAULT,    TK_AUTOINCR,   TK_TO,         
-    TK_IN,         TK_CAST,       TK_COLUMNKW,   TK_COMMIT,     TK_CONFLICT,   
-    TK_JOIN_KW,    TK_CTIME_KW,   TK_CTIME_KW,   TK_PRIMARY,    TK_DEFERRED,   
-    TK_DISTINCT,   TK_IS,         TK_DROP,       TK_FAIL,       TK_FROM,       
-    TK_JOIN_KW,    TK_LIKE_KW,    TK_BY,         TK_IF,         TK_INTO,       
-    TK_OFFSET,     TK_OF,         TK_SET,        TK_ISNULL,     TK_ORDER,      
-    TK_RESTRICT,   TK_JOIN_KW,    TK_JOIN_KW,    TK_ROLLBACK,   TK_ROW,        
-    TK_UNION,      TK_USING,      TK_VACUUM,     TK_VIEW,       TK_INITIALLY,  
-    TK_ALL,        
+  static const unsigned char aCode[117] = {
+    TK_REINDEX,    TK_INDEXED,    TK_INDEX,      TK_DESC,       TK_ESCAPE,     
+    TK_EACH,       TK_CHECK,      TK_KEY,        TK_BEFORE,     TK_FOREIGN,    
+    TK_FOR,        TK_IGNORE,     TK_LIKE_KW,    TK_EXPLAIN,    TK_INSTEAD,    
+    TK_ADD,        TK_DATABASE,   TK_AS,         TK_SELECT,     TK_TABLE,      
+    TK_JOIN_KW,    TK_THEN,       TK_END,        TK_DEFERRABLE, TK_ELSE,       
+    TK_EXCEPT,     TK_TRANSACTION,TK_ON,         TK_JOIN_KW,    TK_ALTER,      
+    TK_RAISE,      TK_EXCLUSIVE,  TK_EXISTS,     TK_CONSTRAINT, TK_INTERSECT,  
+    TK_TRIGGER,    TK_REFERENCES, TK_UNIQUE,     TK_QUERY,      TK_ATTACH,     
+    TK_HAVING,     TK_GROUP,      TK_UPDATE,     TK_TEMP,       TK_TEMP,       
+    TK_OR,         TK_BEGIN,      TK_JOIN_KW,    TK_RENAME,     TK_BETWEEN,    
+    TK_NOTNULL,    TK_NOT,        TK_NULL,       TK_LIKE_KW,    TK_CASCADE,    
+    TK_ASC,        TK_DELETE,     TK_CASE,       TK_COLLATE,    TK_CREATE,     
+    TK_CTIME_KW,   TK_DETACH,     TK_IMMEDIATE,  TK_JOIN,       TK_INSERT,     
+    TK_MATCH,      TK_PLAN,       TK_ANALYZE,    TK_PRAGMA,     TK_ABORT,      
+    TK_VALUES,     TK_VIRTUAL,    TK_LIMIT,      TK_WHEN,       TK_WHERE,      
+    TK_REPLACE,    TK_AFTER,      TK_RESTRICT,   TK_AND,        TK_DEFAULT,    
+    TK_AUTOINCR,   TK_TO,         TK_IN,         TK_CAST,       TK_COLUMNKW,   
+    TK_COMMIT,     TK_CONFLICT,   TK_JOIN_KW,    TK_CTIME_KW,   TK_CTIME_KW,   
+    TK_PRIMARY,    TK_DEFERRED,   TK_DISTINCT,   TK_IS,         TK_DROP,       
+    TK_FAIL,       TK_FROM,       TK_JOIN_KW,    TK_LIKE_KW,    TK_BY,         
+    TK_IF,         TK_INTO,       TK_OFFSET,     TK_OF,         TK_SET,        
+    TK_ISNULL,     TK_ORDER,      TK_JOIN_KW,    TK_JOIN_KW,    TK_ROLLBACK,   
+    TK_ROW,        TK_UNION,      TK_USING,      TK_VACUUM,     TK_VIEW,       
+    TK_INITIALLY,  TK_ALL,        
   };
   int h, i;
   if( n<2 ) return TK_ID;
@@ -74065,7 +82228,7 @@ SQLITE_PRIVATE const char sqlite3IsEbcdicIdChar[] = {
 ** Return the length of the token that begins at z[0]. 
 ** Store the token type in *tokenType before returning.
 */
-static int getToken(const unsigned char *z, int *tokenType){
+SQLITE_PRIVATE int sqlite3GetToken(const unsigned char *z, int *tokenType){
   int i, c;
   switch( *z ){
     case ' ': case '\t': case '\n': case '\f': case '\r': {
@@ -74076,7 +82239,7 @@ static int getToken(const unsigned char *z, int *tokenType){
     case '-': {
       if( z[1]=='-' ){
         for(i=2; (c=z[i])!=0 && c!='\n'; i++){}
-        *tokenType = TK_COMMENT;
+        *tokenType = TK_SPACE;
         return i;
       }
       *tokenType = TK_MINUS;
@@ -74109,7 +82272,7 @@ static int getToken(const unsigned char *z, int *tokenType){
       }
       for(i=3, c=z[2]; (c!='*' || z[i]!='/') && (c=z[i])!=0; i++){}
       if( c ) i++;
-      *tokenType = TK_COMMENT;
+      *tokenType = TK_SPACE;
       return i;
     }
     case '%': {
@@ -74190,9 +82353,12 @@ static int getToken(const unsigned char *z, int *tokenType){
           }
         }
       }
-      if( c ){
+      if( c=='\'' ){
         *tokenType = TK_STRING;
         return i+1;
+      }else if( c!=0 ){
+        *tokenType = TK_ID;
+        return i+1;
       }else{
         *tokenType = TK_ILLEGAL;
         return i;
@@ -74315,16 +82481,13 @@ static int getToken(const unsigned char *z, int *tokenType){
   *tokenType = TK_ILLEGAL;
   return 1;
 }
-SQLITE_PRIVATE int sqlite3GetToken(const unsigned char *z, int *tokenType){
-  return getToken(z, tokenType);
-}
 
 /*
 ** Run the parser on the given SQL string.  The parser structure is
 ** passed in.  An SQLITE_ status code is returned.  If an error occurs
-** and pzErrMsg!=NULL then an error message might be written into 
-** memory obtained from sqlite3_malloc() and *pzErrMsg made to point to that
-** error message.  Or maybe not.
+** then an and attempt is made to write an error message into 
+** memory obtained from sqlite3_malloc() and to make *pzErrMsg point to that
+** error message.
 */
 SQLITE_PRIVATE int sqlite3RunParser(Parse *pParse, const char *zSql, char **pzErrMsg){
   int nErr = 0;
@@ -74333,13 +82496,16 @@ SQLITE_PRIVATE int sqlite3RunParser(Parse *pParse, const char *zSql, char **pzEr
   int tokenType;
   int lastTokenParsed = -1;
   sqlite3 *db = pParse->db;
+  int mxSqlLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
 
   if( db->activeVdbeCnt==0 ){
     db->u1.isInterrupted = 0;
   }
   pParse->rc = SQLITE_OK;
+  pParse->zTail = pParse->zSql = zSql;
   i = 0;
-  pEngine = sqlite3ParserAlloc((void*(*)(size_t))sqlite3_malloc);
+  assert( pzErrMsg!=0 );
+  pEngine = sqlite3ParserAlloc((void*(*)(size_t))sqlite3Malloc);
   if( pEngine==0 ){
     db->mallocFailed = 1;
     return SQLITE_NOMEM;
@@ -74351,33 +82517,29 @@ SQLITE_PRIVATE int sqlite3RunParser(Parse *pParse, const char *zSql, char **pzEr
   assert( pParse->nVarExpr==0 );
   assert( pParse->nVarExprAlloc==0 );
   assert( pParse->apVarExpr==0 );
-  pParse->zTail = pParse->zSql = zSql;
   while( !db->mallocFailed && zSql[i]!=0 ){
     assert( i>=0 );
     pParse->sLastToken.z = (u8*)&zSql[i];
     assert( pParse->sLastToken.dyn==0 );
-    pParse->sLastToken.n = getToken((unsigned char*)&zSql[i],&tokenType);
+    pParse->sLastToken.n = sqlite3GetToken((unsigned char*)&zSql[i],&tokenType);
     i += pParse->sLastToken.n;
-    if( SQLITE_MAX_SQL_LENGTH>0 && i>SQLITE_MAX_SQL_LENGTH ){
+    if( i>mxSqlLen ){
       pParse->rc = SQLITE_TOOBIG;
       break;
     }
     switch( tokenType ){
-      case TK_SPACE:
-      case TK_COMMENT: {
+      case TK_SPACE: {
         if( db->u1.isInterrupted ){
           pParse->rc = SQLITE_INTERRUPT;
-          sqlite3SetString(pzErrMsg, "interrupt", (char*)0);
+          sqlite3SetString(pzErrMsg, db, "interrupt");
           goto abort_parse;
         }
         break;
       }
       case TK_ILLEGAL: {
-        if( pzErrMsg ){
-          sqlite3_free(*pzErrMsg);
-          *pzErrMsg = sqlite3MPrintf(db, "unrecognized token: \"%T\"",
-                          &pParse->sLastToken);
-        }
+        sqlite3DbFree(db, *pzErrMsg);
+        *pzErrMsg = sqlite3MPrintf(db, "unrecognized token: \"%T\"",
+                        &pParse->sLastToken);
         nErr++;
         goto abort_parse;
       }
@@ -74403,18 +82565,23 @@ abort_parse:
     }
     sqlite3Parser(pEngine, 0, pParse->sLastToken, pParse);
   }
+#ifdef YYTRACKMAXSTACKDEPTH
+  sqlite3StatusSet(SQLITE_STATUS_PARSER_STACK,
+      sqlite3ParserStackPeak(pEngine)
+  );
+#endif /* YYDEBUG */
   sqlite3ParserFree(pEngine, sqlite3_free);
   if( db->mallocFailed ){
     pParse->rc = SQLITE_NOMEM;
   }
   if( pParse->rc!=SQLITE_OK && pParse->rc!=SQLITE_DONE && pParse->zErrMsg==0 ){
-    sqlite3SetString(&pParse->zErrMsg, sqlite3ErrStr(pParse->rc), (char*)0);
+    sqlite3SetString(&pParse->zErrMsg, db, "%s", sqlite3ErrStr(pParse->rc));
   }
   if( pParse->zErrMsg ){
-    if( pzErrMsg && *pzErrMsg==0 ){
+    if( *pzErrMsg==0 ){
       *pzErrMsg = pParse->zErrMsg;
     }else{
-      sqlite3_free(pParse->zErrMsg);
+      sqlite3DbFree(db, pParse->zErrMsg);
     }
     pParse->zErrMsg = 0;
     nErr++;
@@ -74425,11 +82592,14 @@ abort_parse:
   }
 #ifndef SQLITE_OMIT_SHARED_CACHE
   if( pParse->nested==0 ){
-    sqlite3_free(pParse->aTableLock);
+    sqlite3DbFree(db, pParse->aTableLock);
     pParse->aTableLock = 0;
     pParse->nTableLock = 0;
   }
 #endif
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  sqlite3DbFree(db, pParse->apVtabLock);
+#endif
 
   if( !IN_DECLARE_VTAB ){
     /* If the pParse->declareVtab flag is set, do not delete any table 
@@ -74439,8 +82609,14 @@ abort_parse:
     sqlite3DeleteTable(pParse->pNewTable);
   }
 
-  sqlite3DeleteTrigger(pParse->pNewTrigger);
-  sqlite3_free(pParse->apVarExpr);
+  sqlite3DeleteTrigger(db, pParse->pNewTrigger);
+  sqlite3DbFree(db, pParse->apVarExpr);
+  sqlite3DbFree(db, pParse->aAlias);
+  while( pParse->pZombieTab ){
+    Table *p = pParse->pZombieTab;
+    pParse->pZombieTab = p->pNextZombie;
+    sqlite3DeleteTable(p);
+  }
   if( nErr>0 && (pParse->rc==SQLITE_OK || pParse->rc==SQLITE_DONE) ){
     pParse->rc = SQLITE_ERROR;
   }
@@ -74467,7 +82643,7 @@ abort_parse:
 ** separating it out, the code will be automatically omitted from
 ** static links that do not use it.
 **
-** $Id: complete.c,v 1.6 2007/08/27 23:26:59 drh Exp $
+** $Id: complete.c,v 1.7 2008/06/13 18:24:27 drh Exp $
 */
 #ifndef SQLITE_OMIT_COMPLETE
 
@@ -74708,11 +82884,17 @@ SQLITE_API int sqlite3_complete16(const void *zSql){
   char const *zSql8;
   int rc = SQLITE_NOMEM;
 
+#ifndef SQLITE_OMIT_AUTOINIT
+  rc = sqlite3_initialize();
+  if( rc ) return rc;
+#endif
   pVal = sqlite3ValueNew(0);
   sqlite3ValueSetStr(pVal, -1, zSql, SQLITE_UTF16NATIVE, SQLITE_STATIC);
   zSql8 = sqlite3ValueText(pVal, SQLITE_UTF8);
   if( zSql8 ){
     rc = sqlite3_complete(zSql8);
+  }else{
+    rc = SQLITE_NOMEM;
   }
   sqlite3ValueFree(pVal);
   return sqlite3ApiExit(0, rc);
@@ -74738,8 +82920,9 @@ SQLITE_API int sqlite3_complete16(const void *zSql){
 ** other files are for internal use by SQLite and should not be
 ** accessed by users of the library.
 **
-** $Id: main.c,v 1.421 2008/03/07 21:37:19 drh Exp $
+** $Id: main.c,v 1.508 2008/10/12 00:27:53 shane Exp $
 */
+
 #ifdef SQLITE_ENABLE_FTS3
 /************** Include fts3.h in the middle of main.c ***********************/
 /************** Begin file fts3.h ********************************************/
@@ -74772,6 +82955,71 @@ SQLITE_PRIVATE int sqlite3Fts3Init(sqlite3 *db);
 /************** End of fts3.h ************************************************/
 /************** Continuing where we left off in main.c ***********************/
 #endif
+#ifdef SQLITE_ENABLE_RTREE
+/************** Include rtree.h in the middle of main.c **********************/
+/************** Begin file rtree.h *******************************************/
+/*
+** 2008 May 26
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This header file is used by programs that want to link against the
+** RTREE library.  All it does is declare the sqlite3RtreeInit() interface.
+*/
+
+#if 0
+extern "C" {
+#endif  /* __cplusplus */
+
+SQLITE_PRIVATE int sqlite3RtreeInit(sqlite3 *db);
+
+#if 0
+}  /* extern "C" */
+#endif  /* __cplusplus */
+
+/************** End of rtree.h ***********************************************/
+/************** Continuing where we left off in main.c ***********************/
+#endif
+#ifdef SQLITE_ENABLE_ICU
+/************** Include sqliteicu.h in the middle of main.c ******************/
+/************** Begin file sqliteicu.h ***************************************/
+/*
+** 2008 May 26
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This header file is used by programs that want to link against the
+** ICU extension.  All it does is declare the sqlite3IcuInit() interface.
+*/
+
+#if 0
+extern "C" {
+#endif  /* __cplusplus */
+
+SQLITE_PRIVATE int sqlite3IcuInit(sqlite3 *db);
+
+#if 0
+}  /* extern "C" */
+#endif  /* __cplusplus */
+
+
+/************** End of sqliteicu.h *******************************************/
+/************** Continuing where we left off in main.c ***********************/
+#endif
 
 /*
 ** The version of the library
@@ -74781,6 +83029,7 @@ SQLITE_API const char *sqlite3_libversion(void){ return sqlite3_version; }
 SQLITE_API int sqlite3_libversion_number(void){ return SQLITE_VERSION_NUMBER; }
 SQLITE_API int sqlite3_threadsafe(void){ return SQLITE_THREADSAFE; }
 
+#if !defined(SQLITE_OMIT_TRACE) && defined(SQLITE_ENABLE_IOTRACE)
 /*
 ** If the following function pointer is not NULL and if
 ** SQLITE_ENABLE_IOTRACE is enabled, then messages describing
@@ -74788,6 +83037,7 @@ SQLITE_API int sqlite3_threadsafe(void){ return SQLITE_THREADSAFE; }
 ** are intended for debugging activity only.
 */
 SQLITE_PRIVATE void (*sqlite3IoTrace)(const char*, ...) = 0;
+#endif
 
 /*
 ** If the following global variable points to a string which is the
@@ -74798,12 +83048,405 @@ SQLITE_PRIVATE void (*sqlite3IoTrace)(const char*, ...) = 0;
 */
 SQLITE_API char *sqlite3_temp_directory = 0;
 
+/*
+** Initialize SQLite.  
+**
+** This routine must be called to initialize the memory allocation,
+** VFS, and mutex subsystems prior to doing any serious work with
+** SQLite.  But as long as you do not compile with SQLITE_OMIT_AUTOINIT
+** this routine will be called automatically by key routines such as
+** sqlite3_open().  
+**
+** This routine is a no-op except on its very first call for the process,
+** or for the first call after a call to sqlite3_shutdown.
+**
+** The first thread to call this routine runs the initialization to
+** completion.  If subsequent threads call this routine before the first
+** thread has finished the initialization process, then the subsequent
+** threads must block until the first thread finishes with the initialization.
+**
+** The first thread might call this routine recursively.  Recursive
+** calls to this routine should not block, of course.  Otherwise the
+** initialization process would never complete.
+**
+** Let X be the first thread to enter this routine.  Let Y be some other
+** thread.  Then while the initial invocation of this routine by X is
+** incomplete, it is required that:
+**
+**    *  Calls to this routine from Y must block until the outer-most
+**       call by X completes.
+**
+**    *  Recursive calls to this routine from thread X return immediately
+**       without blocking.
+*/
+SQLITE_API int sqlite3_initialize(void){
+  sqlite3_mutex *pMaster;                      /* The main static mutex */
+  int rc;                                      /* Result code */
+
+#ifdef SQLITE_OMIT_WSD
+  rc = sqlite3_wsd_init(4096, 24);
+  if( rc!=SQLITE_OK ){
+    return rc;
+  }
+#endif
+
+  /* If SQLite is already completely initialized, then this call
+  ** to sqlite3_initialize() should be a no-op.  But the initialization
+  ** must be complete.  So isInit must not be set until the very end
+  ** of this routine.
+  */
+  if( sqlite3GlobalConfig.isInit ) return SQLITE_OK;
+
+  /* Make sure the mutex subsystem is initialized.  If unable to 
+  ** initialize the mutex subsystem, return early with the error.
+  ** If the system is so sick that we are unable to allocate a mutex,
+  ** there is not much SQLite is going to be able to do.
+  **
+  ** The mutex subsystem must take care of serializing its own
+  ** initialization.
+  */
+  rc = sqlite3MutexInit();
+  if( rc ) return rc;
+
+  /* Initialize the malloc() system and the recursive pInitMutex mutex.
+  ** This operation is protected by the STATIC_MASTER mutex.  Note that
+  ** MutexAlloc() is called for a static mutex prior to initializing the
+  ** malloc subsystem - this implies that the allocation of a static
+  ** mutex must not require support from the malloc subsystem.
+  */
+  pMaster = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+  sqlite3_mutex_enter(pMaster);
+  if( !sqlite3GlobalConfig.isMallocInit ){
+    rc = sqlite3MallocInit();
+  }
+  if( rc==SQLITE_OK ){
+    sqlite3GlobalConfig.isMallocInit = 1;
+    if( !sqlite3GlobalConfig.pInitMutex ){
+      sqlite3GlobalConfig.pInitMutex = sqlite3MutexAlloc(SQLITE_MUTEX_RECURSIVE);
+      if( sqlite3GlobalConfig.bCoreMutex && !sqlite3GlobalConfig.pInitMutex ){
+        rc = SQLITE_NOMEM;
+      }
+    }
+  }
+  if( rc==SQLITE_OK ){
+    sqlite3GlobalConfig.nRefInitMutex++;
+  }
+  sqlite3_mutex_leave(pMaster);
+
+  /* If unable to initialize the malloc subsystem, then return early.
+  ** There is little hope of getting SQLite to run if the malloc
+  ** subsystem cannot be initialized.
+  */
+  if( rc!=SQLITE_OK ){
+    return rc;
+  }
+
+  /* Do the rest of the initialization under the recursive mutex so
+  ** that we will be able to handle recursive calls into
+  ** sqlite3_initialize().  The recursive calls normally come through
+  ** sqlite3_os_init() when it invokes sqlite3_vfs_register(), but other
+  ** recursive calls might also be possible.
+  */
+  sqlite3_mutex_enter(sqlite3GlobalConfig.pInitMutex);
+  if( sqlite3GlobalConfig.isInit==0 && sqlite3GlobalConfig.inProgress==0 ){
+    FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
+    sqlite3GlobalConfig.inProgress = 1;
+    memset(pHash, 0, sizeof(sqlite3GlobalFunctions));
+    sqlite3RegisterGlobalFunctions();
+    rc = sqlite3_os_init();
+    if( rc==SQLITE_OK ){
+      rc = sqlite3PcacheInitialize();
+      sqlite3PCacheBufferSetup( sqlite3GlobalConfig.pPage, 
+          sqlite3GlobalConfig.szPage, sqlite3GlobalConfig.nPage);
+    }
+    sqlite3GlobalConfig.inProgress = 0;
+    sqlite3GlobalConfig.isInit = (rc==SQLITE_OK ? 1 : 0);
+  }
+  sqlite3_mutex_leave(sqlite3GlobalConfig.pInitMutex);
+
+  /* Go back under the static mutex and clean up the recursive
+  ** mutex to prevent a resource leak.
+  */
+  sqlite3_mutex_enter(pMaster);
+  sqlite3GlobalConfig.nRefInitMutex--;
+  if( sqlite3GlobalConfig.nRefInitMutex<=0 ){
+    assert( sqlite3GlobalConfig.nRefInitMutex==0 );
+    sqlite3_mutex_free(sqlite3GlobalConfig.pInitMutex);
+    sqlite3GlobalConfig.pInitMutex = 0;
+  }
+  sqlite3_mutex_leave(pMaster);
+
+  /* The following is just a sanity check to make sure SQLite has
+  ** been compiled correctly.  It is important to run this code, but
+  ** we don't want to run it too often and soak up CPU cycles for no
+  ** reason.  So we run it once during initialization.
+  */
+#ifndef NDEBUG
+  /* This section of code's only "output" is via assert() statements. */
+  if ( rc==SQLITE_OK ){
+    u64 x = (((u64)1)<<63)-1;
+    double y;
+    assert(sizeof(x)==8);
+    assert(sizeof(x)==sizeof(y));
+    memcpy(&y, &x, 8);
+    assert( sqlite3IsNaN(y) );
+  }
+#endif
+
+  return rc;
+}
+
+/*
+** Undo the effects of sqlite3_initialize().  Must not be called while
+** there are outstanding database connections or memory allocations or
+** while any part of SQLite is otherwise in use in any thread.  This
+** routine is not threadsafe.  Not by a long shot.
+*/
+SQLITE_API int sqlite3_shutdown(void){
+  sqlite3GlobalConfig.isMallocInit = 0;
+  sqlite3PcacheShutdown();
+  if( sqlite3GlobalConfig.isInit ){
+    sqlite3_os_end();
+  }
+  sqlite3MallocEnd();
+  sqlite3MutexEnd();
+  sqlite3GlobalConfig.isInit = 0;
+  return SQLITE_OK;
+}
+
+/*
+** This API allows applications to modify the global configuration of
+** the SQLite library at run-time.
+**
+** This routine should only be called when there are no outstanding
+** database connections or memory allocations.  This routine is not
+** threadsafe.  Failure to heed these warnings can lead to unpredictable
+** behavior.
+*/
+SQLITE_API int sqlite3_config(int op, ...){
+  va_list ap;
+  int rc = SQLITE_OK;
+
+  /* sqlite3_config() shall return SQLITE_MISUSE if it is invoked while
+  ** the SQLite library is in use. */
+  if( sqlite3GlobalConfig.isInit ) return SQLITE_MISUSE;
+
+  va_start(ap, op);
+  switch( op ){
+
+    /* Mutex configuration options are only available in a threadsafe
+    ** compile. 
+    */
+#if SQLITE_THREADSAFE
+    case SQLITE_CONFIG_SINGLETHREAD: {
+      /* Disable all mutexing */
+      sqlite3GlobalConfig.bCoreMutex = 0;
+      sqlite3GlobalConfig.bFullMutex = 0;
+      break;
+    }
+    case SQLITE_CONFIG_MULTITHREAD: {
+      /* Disable mutexing of database connections */
+      /* Enable mutexing of core data structures */
+      sqlite3GlobalConfig.bCoreMutex = 1;
+      sqlite3GlobalConfig.bFullMutex = 0;
+      break;
+    }
+    case SQLITE_CONFIG_SERIALIZED: {
+      /* Enable all mutexing */
+      sqlite3GlobalConfig.bCoreMutex = 1;
+      sqlite3GlobalConfig.bFullMutex = 1;
+      break;
+    }
+    case SQLITE_CONFIG_MUTEX: {
+      /* Specify an alternative mutex implementation */
+      sqlite3GlobalConfig.mutex = *va_arg(ap, sqlite3_mutex_methods*);
+      break;
+    }
+    case SQLITE_CONFIG_GETMUTEX: {
+      /* Retrieve the current mutex implementation */
+      *va_arg(ap, sqlite3_mutex_methods*) = sqlite3GlobalConfig.mutex;
+      break;
+    }
+#endif
+
+
+    case SQLITE_CONFIG_MALLOC: {
+      /* Specify an alternative malloc implementation */
+      sqlite3GlobalConfig.m = *va_arg(ap, sqlite3_mem_methods*);
+      break;
+    }
+    case SQLITE_CONFIG_GETMALLOC: {
+      /* Retrieve the current malloc() implementation */
+      if( sqlite3GlobalConfig.m.xMalloc==0 ) sqlite3MemSetDefault();
+      *va_arg(ap, sqlite3_mem_methods*) = sqlite3GlobalConfig.m;
+      break;
+    }
+    case SQLITE_CONFIG_MEMSTATUS: {
+      /* Enable or disable the malloc status collection */
+      sqlite3GlobalConfig.bMemstat = va_arg(ap, int);
+      break;
+    }
+    case SQLITE_CONFIG_SCRATCH: {
+      /* Designate a buffer for scratch memory space */
+      sqlite3GlobalConfig.pScratch = va_arg(ap, void*);
+      sqlite3GlobalConfig.szScratch = va_arg(ap, int);
+      sqlite3GlobalConfig.nScratch = va_arg(ap, int);
+      break;
+    }
+    case SQLITE_CONFIG_PAGECACHE: {
+      /* Designate a buffer for scratch memory space */
+      sqlite3GlobalConfig.pPage = va_arg(ap, void*);
+      sqlite3GlobalConfig.szPage = va_arg(ap, int);
+      sqlite3GlobalConfig.nPage = va_arg(ap, int);
+      break;
+    }
+
+#if defined(SQLITE_ENABLE_MEMSYS3) || defined(SQLITE_ENABLE_MEMSYS5)
+    case SQLITE_CONFIG_HEAP: {
+      /* Designate a buffer for heap memory space */
+      sqlite3GlobalConfig.pHeap = va_arg(ap, void*);
+      sqlite3GlobalConfig.nHeap = va_arg(ap, int);
+      sqlite3GlobalConfig.mnReq = va_arg(ap, int);
+
+      if( sqlite3GlobalConfig.pHeap==0 ){
+        /* If the heap pointer is NULL, then restore the malloc implementation
+        ** back to NULL pointers too.  This will cause the malloc to go
+        ** back to its default implementation when sqlite3_initialize() is
+        ** run.
+        */
+        memset(&sqlite3GlobalConfig.m, 0, sizeof(sqlite3GlobalConfig.m));
+      }else{
+        /* The heap pointer is not NULL, then install one of the
+        ** mem5.c/mem3.c methods. If neither ENABLE_MEMSYS3 nor
+        ** ENABLE_MEMSYS5 is defined, return an error.
+        ** the default case and return an error.
+        */
+#ifdef SQLITE_ENABLE_MEMSYS3
+        sqlite3GlobalConfig.m = *sqlite3MemGetMemsys3();
+#endif
+#ifdef SQLITE_ENABLE_MEMSYS5
+        sqlite3GlobalConfig.m = *sqlite3MemGetMemsys5();
+#endif
+      }
+      break;
+    }
+#endif
+
+#if defined(SQLITE_ENABLE_MEMSYS6)
+    case SQLITE_CONFIG_CHUNKALLOC: {
+      sqlite3GlobalConfig.nSmall = va_arg(ap, int);
+      sqlite3GlobalConfig.m = *sqlite3MemGetMemsys6();
+      break;
+    }
+#endif
+
+    case SQLITE_CONFIG_LOOKASIDE: {
+      sqlite3GlobalConfig.szLookaside = va_arg(ap, int);
+      sqlite3GlobalConfig.nLookaside = va_arg(ap, int);
+      break;
+    }
+
+    default: {
+      rc = SQLITE_ERROR;
+      break;
+    }
+  }
+  va_end(ap);
+  return rc;
+}
+
+/*
+** Set up the lookaside buffers for a database connection.
+** Return SQLITE_OK on success.  
+** If lookaside is already active, return SQLITE_BUSY.
+**
+** The sz parameter is the number of bytes in each lookaside slot.
+** The cnt parameter is the number of slots.  If pStart is NULL the
+** space for the lookaside memory is obtained from sqlite3_malloc().
+** If pStart is not NULL then it is sz*cnt bytes of memory to use for
+** the lookaside memory.
+*/
+static int setupLookaside(sqlite3 *db, void *pBuf, int sz, int cnt){
+  void *pStart;
+  if( db->lookaside.nOut ){
+    return SQLITE_BUSY;
+  }
+  if( sz<0 ) sz = 0;
+  if( cnt<0 ) cnt = 0;
+  if( pBuf==0 ){
+    sz = (sz + 7)&~7;
+    sqlite3BeginBenignMalloc();
+    pStart = sqlite3Malloc( sz*cnt );
+    sqlite3EndBenignMalloc();
+  }else{
+    sz = sz&~7;
+    pStart = pBuf;
+  }
+  if( db->lookaside.bMalloced ){
+    sqlite3_free(db->lookaside.pStart);
+  }
+  db->lookaside.pStart = pStart;
+  db->lookaside.pFree = 0;
+  db->lookaside.sz = sz;
+  db->lookaside.bMalloced = pBuf==0;
+  if( pStart ){
+    int i;
+    LookasideSlot *p;
+    p = (LookasideSlot*)pStart;
+    for(i=cnt-1; i>=0; i--){
+      p->pNext = db->lookaside.pFree;
+      db->lookaside.pFree = p;
+      p = (LookasideSlot*)&((u8*)p)[sz];
+    }
+    db->lookaside.pEnd = p;
+    db->lookaside.bEnabled = 1;
+  }else{
+    db->lookaside.pEnd = 0;
+    db->lookaside.bEnabled = 0;
+  }
+  return SQLITE_OK;
+}
+
+/*
+** Configuration settings for an individual database connection
+*/
+SQLITE_API int sqlite3_db_config(sqlite3 *db, int op, ...){
+  va_list ap;
+  int rc;
+  va_start(ap, op);
+  switch( op ){
+    case SQLITE_DBCONFIG_LOOKASIDE: {
+      void *pBuf = va_arg(ap, void*);
+      int sz = va_arg(ap, int);
+      int cnt = va_arg(ap, int);
+      rc = setupLookaside(db, pBuf, sz, cnt);
+      break;
+    }
+    default: {
+      rc = SQLITE_ERROR;
+      break;
+    }
+  }
+  va_end(ap);
+  return rc;
+}
+
+/*
+** Routine needed to support the testcase() macro.
+*/
+#ifdef SQLITE_COVERAGE_TEST
+SQLITE_PRIVATE void sqlite3Coverage(int x){
+  static int dummy = 0;
+  dummy += x;
+}
+#endif
+
 
 /*
 ** Return true if the buffer z[0..n-1] contains all spaces.
 */
 static int allSpaces(const char *z, int n){
-  while( n>0 && z[--n]==' ' ){}
+  while( n>0 && z[n-1]==' ' ){ n--; }
   return n==0;
 }
 
@@ -74933,14 +83576,17 @@ SQLITE_API int sqlite3_close(sqlite3 *db){
   sqlite3ResetInternalSchema(db, 0);
   assert( db->nDb<=2 );
   assert( db->aDb==db->aDbStatic );
-  for(i=sqliteHashFirst(&db->aFunc); i; i=sqliteHashNext(i)){
-    FuncDef *pFunc, *pNext;
-    for(pFunc = (FuncDef*)sqliteHashData(i); pFunc; pFunc=pNext){
-      pNext = pFunc->pNext;
-      sqlite3_free(pFunc);
+  for(j=0; jaFunc.a); j++){
+    FuncDef *pNext, *pHash, *p;
+    for(p=db->aFunc.a[j]; p; p=pHash){
+      pHash = p->pHash;
+      while( p ){
+        pNext = p->pNext;
+        sqlite3DbFree(db, p);
+        p = pNext;
+      }
     }
   }
-
   for(i=sqliteHashFirst(&db->aCollSeq); i; i=sqliteHashNext(i)){
     CollSeq *pColl = (CollSeq *)sqliteHashData(i);
     /* Invoke any destructors registered for collation sequence user data. */
@@ -74949,7 +83595,7 @@ SQLITE_API int sqlite3_close(sqlite3 *db){
         pColl[j].xDel(pColl[j].pUser);
       }
     }
-    sqlite3_free(pColl);
+    sqlite3DbFree(db, pColl);
   }
   sqlite3HashClear(&db->aCollSeq);
 #ifndef SQLITE_OMIT_VIRTUALTABLE
@@ -74958,12 +83604,11 @@ SQLITE_API int sqlite3_close(sqlite3 *db){
     if( pMod->xDestroy ){
       pMod->xDestroy(pMod->pAux);
     }
-    sqlite3_free(pMod);
+    sqlite3DbFree(db, pMod);
   }
   sqlite3HashClear(&db->aModule);
 #endif
 
-  sqlite3HashClear(&db->aFunc);
   sqlite3Error(db, SQLITE_OK, 0); /* Deallocates any cached error strings. */
   if( db->pErr ){
     sqlite3ValueFree(db->pErr);
@@ -74978,10 +83623,14 @@ SQLITE_API int sqlite3_close(sqlite3 *db){
   ** the same sqliteMalloc() as the one that allocates the database 
   ** structure?
   */
-  sqlite3_free(db->aDb[1].pSchema);
+  sqlite3DbFree(db, db->aDb[1].pSchema);
   sqlite3_mutex_leave(db->mutex);
   db->magic = SQLITE_MAGIC_CLOSED;
   sqlite3_mutex_free(db->mutex);
+  assert( db->lookaside.nOut==0 );  /* Fails on a lookaside memory leak */
+  if( db->lookaside.bMalloced ){
+    sqlite3_free(db->lookaside.pStart);
+  }
   sqlite3_free(db);
   return SQLITE_OK;
 }
@@ -74993,7 +83642,7 @@ SQLITE_PRIVATE void sqlite3RollbackAll(sqlite3 *db){
   int i;
   int inTrans = 0;
   assert( sqlite3_mutex_held(db->mutex) );
-  sqlite3FaultBenign(SQLITE_FAULTINJECTOR_MALLOC, 1);
+  sqlite3BeginBenignMalloc();
   for(i=0; inDb; i++){
     if( db->aDb[i].pBt ){
       if( sqlite3BtreeIsInTrans(db->aDb[i].pBt) ){
@@ -75004,7 +83653,7 @@ SQLITE_PRIVATE void sqlite3RollbackAll(sqlite3 *db){
     }
   }
   sqlite3VtabRollback(db);
-  sqlite3FaultBenign(SQLITE_FAULTINJECTOR_MALLOC, 0);
+  sqlite3EndBenignMalloc();
 
   if( db->flags&SQLITE_InternChanges ){
     sqlite3ExpirePreparedStatements(db);
@@ -75045,7 +83694,7 @@ SQLITE_PRIVATE const char *sqlite3ErrStr(int rc){
     case SQLITE_CONSTRAINT: z = "constraint failed";                     break;
     case SQLITE_MISMATCH:   z = "datatype mismatch";                     break;
     case SQLITE_MISUSE:     z = "library routine called out of sequence";break;
-    case SQLITE_NOLFS:      z = "kernel lacks large file support";       break;
+    case SQLITE_NOLFS:      z = "large file support is disabled";        break;
     case SQLITE_AUTH:       z = "authorization denied";                  break;
     case SQLITE_FORMAT:     z = "auxiliary database format error";       break;
     case SQLITE_RANGE:      z = "bind or column index out of range";     break;
@@ -75065,7 +83714,7 @@ static int sqliteDefaultBusyCallback(
  void *ptr,               /* Database connection */
  int count                /* Number of times table has been busy */
 ){
-#if OS_WIN || (defined(HAVE_USLEEP) && HAVE_USLEEP)
+#if SQLITE_OS_WIN || (defined(HAVE_USLEEP) && HAVE_USLEEP)
   static const u8 delays[] =
      { 1, 2, 5, 10, 15, 20, 25, 25,  25,  50,  50, 100 };
   static const u8 totals[] =
@@ -75109,7 +83758,7 @@ static int sqliteDefaultBusyCallback(
 */
 SQLITE_PRIVATE int sqlite3InvokeBusyHandler(BusyHandler *p){
   int rc;
-  if( p==0 || p->xFunc==0 || p->nBusy<0 ) return 0;
+  if( NEVER(p==0) || p->xFunc==0 || p->nBusy<0 ) return 0;
   rc = p->xFunc(p->pArg, p->nBusy);
   if( rc==0 ){
     p->nBusy = -1;
@@ -75148,19 +83797,17 @@ SQLITE_API void sqlite3_progress_handler(
   int (*xProgress)(void*), 
   void *pArg
 ){
-  if( sqlite3SafetyCheckOk(db) ){
-    sqlite3_mutex_enter(db->mutex);
-    if( nOps>0 ){
-      db->xProgress = xProgress;
-      db->nProgressOps = nOps;
-      db->pProgressArg = pArg;
-    }else{
-      db->xProgress = 0;
-      db->nProgressOps = 0;
-      db->pProgressArg = 0;
-    }
-    sqlite3_mutex_leave(db->mutex);
+  sqlite3_mutex_enter(db->mutex);
+  if( nOps>0 ){
+    db->xProgress = xProgress;
+    db->nProgressOps = nOps;
+    db->pProgressArg = pArg;
+  }else{
+    db->xProgress = 0;
+    db->nProgressOps = 0;
+    db->pProgressArg = 0;
   }
+  sqlite3_mutex_leave(db->mutex);
 }
 #endif
 
@@ -75183,9 +83830,7 @@ SQLITE_API int sqlite3_busy_timeout(sqlite3 *db, int ms){
 ** Cause any pending operation to stop at its earliest opportunity.
 */
 SQLITE_API void sqlite3_interrupt(sqlite3 *db){
-  if( sqlite3SafetyCheckOk(db) ){
-    db->u1.isInterrupted = 1;
-  }
+  db->u1.isInterrupted = 1;
 }
 
 
@@ -75213,8 +83858,8 @@ SQLITE_PRIVATE int sqlite3CreateFunc(
       (xFunc && (xFinal || xStep)) || 
       (!xFunc && (xFinal && !xStep)) ||
       (!xFunc && (!xFinal && xStep)) ||
-      (nArg<-1 || nArg>127) ||
-      (255<(nName = strlen(zFunctionName))) ){
+      (nArg<-1 || nArg>SQLITE_MAX_FUNCTION_ARG) ||
+      (255<(nName = sqlite3Strlen(db, zFunctionName))) ){
     sqlite3Error(db, SQLITE_ERROR, "bad parameters");
     return SQLITE_ERROR;
   }
@@ -75292,7 +83937,6 @@ SQLITE_API int sqlite3_create_function(
 ){
   int rc;
   sqlite3_mutex_enter(db->mutex);
-  assert( !db->mallocFailed );
   rc = sqlite3CreateFunc(db, zFunctionName, nArg, enc, p, xFunc, xStep, xFinal);
   rc = sqlite3ApiExit(db, rc);
   sqlite3_mutex_leave(db->mutex);
@@ -75316,7 +83960,7 @@ SQLITE_API int sqlite3_create_function16(
   assert( !db->mallocFailed );
   zFunc8 = sqlite3Utf16to8(db, zFunctionName, -1);
   rc = sqlite3CreateFunc(db, zFunc8, nArg, eTextRep, p, xFunc, xStep, xFinal);
-  sqlite3_free(zFunc8);
+  sqlite3DbFree(db, zFunc8);
   rc = sqlite3ApiExit(db, rc);
   sqlite3_mutex_leave(db->mutex);
   return rc;
@@ -75341,7 +83985,7 @@ SQLITE_API int sqlite3_overload_function(
   const char *zName,
   int nArg
 ){
-  int nName = strlen(zName);
+  int nName = sqlite3Strlen(db, zName);
   int rc;
   sqlite3_mutex_enter(db->mutex);
   if( sqlite3FindFunction(db, zName, nName, nArg, SQLITE_UTF8, 0)==0 ){
@@ -75461,19 +84105,19 @@ SQLITE_API void *sqlite3_rollback_hook(
 **
 ** A virtual database can be either a disk file (that is automatically
 ** deleted when the file is closed) or it an be held entirely in memory,
-** depending on the values of the TEMP_STORE compile-time macro and the
+** depending on the values of the SQLITE_TEMP_STORE compile-time macro and the
 ** db->temp_store variable, according to the following chart:
 **
-**       TEMP_STORE     db->temp_store     Location of temporary database
-**       ----------     --------------     ------------------------------
-**           0               any             file
-**           1                1              file
-**           1                2              memory
-**           1                0              file
-**           2                1              file
-**           2                2              memory
-**           2                0              memory
-**           3               any             memory
+**   SQLITE_TEMP_STORE     db->temp_store     Location of temporary database
+**   -----------------     --------------     ------------------------------
+**   0                     any                file
+**   1                     1                  file
+**   1                     2                  memory
+**   1                     0                  file
+**   2                     1                  file
+**   2                     2                  memory
+**   2                     0                  memory
+**   3                     any                memory
 */
 SQLITE_PRIVATE int sqlite3BtreeFactory(
   const sqlite3 *db,        /* Main database when opening aux otherwise 0 */
@@ -75495,17 +84139,17 @@ SQLITE_PRIVATE int sqlite3BtreeFactory(
     btFlags |= BTREE_NO_READLOCK;
   }
   if( zFilename==0 ){
-#if TEMP_STORE==0
+#if SQLITE_TEMP_STORE==0
     /* Do nothing */
 #endif
 #ifndef SQLITE_OMIT_MEMORYDB
-#if TEMP_STORE==1
+#if SQLITE_TEMP_STORE==1
     if( db->temp_store==2 ) zFilename = ":memory:";
 #endif
-#if TEMP_STORE==2
+#if SQLITE_TEMP_STORE==2
     if( db->temp_store!=1 ) zFilename = ":memory:";
 #endif
-#if TEMP_STORE==3
+#if SQLITE_TEMP_STORE==3
     zFilename = ":memory:";
 #endif
 #endif /* SQLITE_OMIT_MEMORYDB */
@@ -75515,7 +84159,13 @@ SQLITE_PRIVATE int sqlite3BtreeFactory(
     vfsFlags = (vfsFlags & ~SQLITE_OPEN_MAIN_DB) | SQLITE_OPEN_TEMP_DB;
   }
   rc = sqlite3BtreeOpen(zFilename, (sqlite3 *)db, ppBtree, btFlags, vfsFlags);
-  if( rc==SQLITE_OK ){
+
+  /* If the B-Tree was successfully opened, set the pager-cache size to the
+  ** default value. Except, if the call to BtreeOpen() returned a handle
+  ** open on an existing shared pager-cache, do not change the pager-cache 
+  ** size.
+  */
+  if( rc==SQLITE_OK && 0==sqlite3BtreeSchema(*ppBtree, 0, 0) ){
     sqlite3BtreeSetCacheSize(*ppBtree, nCache);
   }
   return rc;
@@ -75530,12 +84180,13 @@ SQLITE_API const char *sqlite3_errmsg(sqlite3 *db){
   if( !db ){
     return sqlite3ErrStr(SQLITE_NOMEM);
   }
-  if( !sqlite3SafetyCheckSickOrOk(db) || db->errCode==SQLITE_MISUSE ){
+  if( !sqlite3SafetyCheckSickOrOk(db) ){
     return sqlite3ErrStr(SQLITE_MISUSE);
   }
   sqlite3_mutex_enter(db->mutex);
   assert( !db->mallocFailed );
   z = (char*)sqlite3_value_text(db->pErr);
+  assert( !db->mallocFailed );
   if( z==0 ){
     z = sqlite3ErrStr(db->errCode);
   }
@@ -75572,7 +84223,7 @@ SQLITE_API const void *sqlite3_errmsg16(sqlite3 *db){
   if( !db ){
     return (void *)(&outOfMemBe[SQLITE_UTF16NATIVE==SQLITE_UTF16LE?1:0]);
   }
-  if( !sqlite3SafetyCheckSickOrOk(db) || db->errCode==SQLITE_MISUSE ){
+  if( !sqlite3SafetyCheckSickOrOk(db) ){
     return (void *)(&misuseBe[SQLITE_UTF16NATIVE==SQLITE_UTF16LE?1:0]);
   }
   sqlite3_mutex_enter(db->mutex);
@@ -75583,7 +84234,12 @@ SQLITE_API const void *sqlite3_errmsg16(sqlite3 *db){
          SQLITE_UTF8, SQLITE_STATIC);
     z = sqlite3_value_text16(db->pErr);
   }
-  sqlite3ApiExit(0, 0);
+  /* A malloc() may have failed within the call to sqlite3_value_text16()
+  ** above. If this is the case, then the db->mallocFailed flag needs to
+  ** be cleared before returning. Do this directly, instead of via
+  ** sqlite3ApiExit(), to avoid setting the database handle error message.
+  */
+  db->mallocFailed = 0;
   sqlite3_mutex_leave(db->mutex);
   return z;
 }
@@ -75617,6 +84273,7 @@ static int createCollation(
 ){
   CollSeq *pColl;
   int enc2;
+  int nName;
   
   assert( sqlite3_mutex_held(db->mutex) );
 
@@ -75628,17 +84285,16 @@ static int createCollation(
   if( enc2==SQLITE_UTF16 ){
     enc2 = SQLITE_UTF16NATIVE;
   }
-
   if( (enc2&~3)!=0 ){
-    sqlite3Error(db, SQLITE_ERROR, "unknown encoding");
-    return SQLITE_ERROR;
+    return SQLITE_MISUSE;
   }
 
   /* Check if this call is removing or replacing an existing collation 
   ** sequence. If so, and there are active VMs, return busy. If there
   ** are no active VMs, invalidate any pre-compiled statements.
   */
-  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, strlen(zName), 0);
+  nName = sqlite3Strlen(db, zName);
+  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, nName, 0);
   if( pColl && pColl->xCmp ){
     if( db->activeVdbeCnt ){
       sqlite3Error(db, SQLITE_BUSY, 
@@ -75654,7 +84310,7 @@ static int createCollation(
     ** to be called.
     */ 
     if( (pColl->enc & ~SQLITE_UTF16_ALIGNED)==enc2 ){
-      CollSeq *aColl = sqlite3HashFind(&db->aCollSeq, zName, strlen(zName));
+      CollSeq *aColl = sqlite3HashFind(&db->aCollSeq, zName, nName);
       int j;
       for(j=0; j<3; j++){
         CollSeq *p = &aColl[j];
@@ -75668,7 +84324,7 @@ static int createCollation(
     }
   }
 
-  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, strlen(zName), 1);
+  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, nName, 1);
   if( pColl ){
     pColl->xCmp = xCompare;
     pColl->pUser = pCtx;
@@ -75681,6 +84337,84 @@ static int createCollation(
 
 
 /*
+** This array defines hard upper bounds on limit values.  The
+** initializer must be kept in sync with the SQLITE_LIMIT_*
+** #defines in sqlite3.h.
+*/
+static const int aHardLimit[] = {
+  SQLITE_MAX_LENGTH,
+  SQLITE_MAX_SQL_LENGTH,
+  SQLITE_MAX_COLUMN,
+  SQLITE_MAX_EXPR_DEPTH,
+  SQLITE_MAX_COMPOUND_SELECT,
+  SQLITE_MAX_VDBE_OP,
+  SQLITE_MAX_FUNCTION_ARG,
+  SQLITE_MAX_ATTACHED,
+  SQLITE_MAX_LIKE_PATTERN_LENGTH,
+  SQLITE_MAX_VARIABLE_NUMBER,
+};
+
+/*
+** Make sure the hard limits are set to reasonable values
+*/
+#if SQLITE_MAX_LENGTH<100
+# error SQLITE_MAX_LENGTH must be at least 100
+#endif
+#if SQLITE_MAX_SQL_LENGTH<100
+# error SQLITE_MAX_SQL_LENGTH must be at least 100
+#endif
+#if SQLITE_MAX_SQL_LENGTH>SQLITE_MAX_LENGTH
+# error SQLITE_MAX_SQL_LENGTH must not be greater than SQLITE_MAX_LENGTH
+#endif
+#if SQLITE_MAX_COMPOUND_SELECT<2
+# error SQLITE_MAX_COMPOUND_SELECT must be at least 2
+#endif
+#if SQLITE_MAX_VDBE_OP<40
+# error SQLITE_MAX_VDBE_OP must be at least 40
+#endif
+#if SQLITE_MAX_FUNCTION_ARG<0 || SQLITE_MAX_FUNCTION_ARG>1000
+# error SQLITE_MAX_FUNCTION_ARG must be between 0 and 1000
+#endif
+#if SQLITE_MAX_ATTACHED<0 || SQLITE_MAX_ATTACHED>30
+# error SQLITE_MAX_ATTACHED must be between 0 and 30
+#endif
+#if SQLITE_MAX_LIKE_PATTERN_LENGTH<1
+# error SQLITE_MAX_LIKE_PATTERN_LENGTH must be at least 1
+#endif
+#if SQLITE_MAX_VARIABLE_NUMBER<1
+# error SQLITE_MAX_VARIABLE_NUMBER must be at least 1
+#endif
+#if SQLITE_MAX_COLUMN>32767
+# error SQLITE_MAX_COLUMN must not exceed 32767
+#endif
+
+
+/*
+** Change the value of a limit.  Report the old value.
+** If an invalid limit index is supplied, report -1.
+** Make no changes but still report the old value if the
+** new limit is negative.
+**
+** A new lower limit does not shrink existing constructs.
+** It merely prevents new constructs that exceed the limit
+** from forming.
+*/
+SQLITE_API int sqlite3_limit(sqlite3 *db, int limitId, int newLimit){
+  int oldLimit;
+  if( limitId<0 || limitId>=SQLITE_N_LIMIT ){
+    return -1;
+  }
+  oldLimit = db->aLimit[limitId];
+  if( newLimit>=0 ){
+    if( newLimit>aHardLimit[limitId] ){
+      newLimit = aHardLimit[limitId];
+    }
+    db->aLimit[limitId] = newLimit;
+  }
+  return oldLimit;
+}
+
+/*
 ** This routine does the work of opening a database on behalf of
 ** sqlite3_open() and sqlite3_open16(). The database filename "zFilename"  
 ** is UTF-8 encoded.
@@ -75694,6 +84428,22 @@ static int openDatabase(
   sqlite3 *db;
   int rc;
   CollSeq *pColl;
+  int isThreadsafe;
+
+#ifndef SQLITE_OMIT_AUTOINIT
+  rc = sqlite3_initialize();
+  if( rc ) return rc;
+#endif
+
+  if( sqlite3GlobalConfig.bCoreMutex==0 ){
+    isThreadsafe = 0;
+  }else if( flags & SQLITE_OPEN_NOMUTEX ){
+    isThreadsafe = 0;
+  }else if( flags & SQLITE_OPEN_FULLMUTEX ){
+    isThreadsafe = 1;
+  }else{
+    isThreadsafe = sqlite3GlobalConfig.bFullMutex;
+  }
 
   /* Remove harmful bits from the flags parameter */
   flags &=  ~( SQLITE_OPEN_DELETEONCLOSE |
@@ -75703,17 +84453,21 @@ static int openDatabase(
                SQLITE_OPEN_MAIN_JOURNAL | 
                SQLITE_OPEN_TEMP_JOURNAL | 
                SQLITE_OPEN_SUBJOURNAL | 
-               SQLITE_OPEN_MASTER_JOURNAL
+               SQLITE_OPEN_MASTER_JOURNAL |
+               SQLITE_OPEN_NOMUTEX |
+               SQLITE_OPEN_FULLMUTEX
              );
 
   /* Allocate the sqlite data structure */
   db = sqlite3MallocZero( sizeof(sqlite3) );
   if( db==0 ) goto opendb_out;
-  db->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_RECURSIVE);
-  if( db->mutex==0 ){
-    sqlite3_free(db);
-    db = 0;
-    goto opendb_out;
+  if( isThreadsafe ){
+    db->mutex = sqlite3MutexAlloc(SQLITE_MUTEX_RECURSIVE);
+    if( db->mutex==0 ){
+      sqlite3_free(db);
+      db = 0;
+      goto opendb_out;
+    }
   }
   sqlite3_mutex_enter(db->mutex);
   db->errMask = 0xff;
@@ -75721,8 +84475,12 @@ static int openDatabase(
   db->nDb = 2;
   db->magic = SQLITE_MAGIC_BUSY;
   db->aDb = db->aDbStatic;
+
+  assert( sizeof(db->aLimit)==sizeof(aHardLimit) );
+  memcpy(db->aLimit, aHardLimit, sizeof(db->aLimit));
   db->autoCommit = 1;
   db->nextAutovac = -1;
+  db->nextPagesize = 0;
   db->flags |= SQLITE_ShortColNames
 #if SQLITE_DEFAULT_FILE_FORMAT<4
                  | SQLITE_LegacyFileFmt
@@ -75731,16 +84489,14 @@ static int openDatabase(
                  | SQLITE_LoadExtension
 #endif
       ;
-  sqlite3HashInit(&db->aFunc, SQLITE_HASH_STRING, 0);
-  sqlite3HashInit(&db->aCollSeq, SQLITE_HASH_STRING, 0);
+  sqlite3HashInit(&db->aCollSeq, 0);
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-  sqlite3HashInit(&db->aModule, SQLITE_HASH_STRING, 0);
+  sqlite3HashInit(&db->aModule, 0);
 #endif
 
   db->pVfs = sqlite3_vfs_find(zVfs);
   if( !db->pVfs ){
     rc = SQLITE_ERROR;
-    db->magic = SQLITE_MAGIC_SICK;
     sqlite3Error(db, rc, "no such vfs: %s", zVfs);
     goto opendb_out;
   }
@@ -75753,13 +84509,11 @@ static int openDatabase(
   createCollation(db, "BINARY", SQLITE_UTF16BE, 0, binCollFunc, 0);
   createCollation(db, "BINARY", SQLITE_UTF16LE, 0, binCollFunc, 0);
   createCollation(db, "RTRIM", SQLITE_UTF8, (void*)1, binCollFunc, 0);
-  if( db->mallocFailed ||
-      (db->pDfltColl = sqlite3FindCollSeq(db, SQLITE_UTF8, "BINARY", 6, 0))==0 
-  ){
-    assert( db->mallocFailed );
-    db->magic = SQLITE_MAGIC_SICK;
+  if( db->mallocFailed ){
     goto opendb_out;
   }
+  db->pDfltColl = sqlite3FindCollSeq(db, SQLITE_UTF8, "BINARY", 6, 0);
+  assert( db->pDfltColl!=0 );
 
   /* Also add a UTF-8 case-insensitive collation sequence. */
   createCollation(db, "NOCASE", SQLITE_UTF8, 0, nocaseCollatingFunc, 0);
@@ -75777,8 +84531,10 @@ static int openDatabase(
                            flags | SQLITE_OPEN_MAIN_DB,
                            &db->aDb[0].pBt);
   if( rc!=SQLITE_OK ){
+    if( rc==SQLITE_IOERR_NOMEM ){
+      rc = SQLITE_NOMEM;
+    }
     sqlite3Error(db, rc, 0);
-    db->magic = SQLITE_MAGIC_SICK;
     goto opendb_out;
   }
   db->aDb[0].pSchema = sqlite3SchemaGet(db, db->aDb[0].pBt);
@@ -75837,10 +84593,16 @@ static int openDatabase(
 
 #ifdef SQLITE_ENABLE_ICU
   if( !db->mallocFailed && rc==SQLITE_OK ){
-    extern int sqlite3IcuInit(sqlite3*);
     rc = sqlite3IcuInit(db);
   }
 #endif
+
+#ifdef SQLITE_ENABLE_RTREE
+  if( !db->mallocFailed && rc==SQLITE_OK){
+    rc = sqlite3RtreeInit(db);
+  }
+#endif
+
   sqlite3Error(db, rc, 0);
 
   /* -DSQLITE_DEFAULT_LOCKING_MODE=1 makes EXCLUSIVE the default locking
@@ -75853,14 +84615,21 @@ static int openDatabase(
                           SQLITE_DEFAULT_LOCKING_MODE);
 #endif
 
+  /* Enable the lookaside-malloc subsystem */
+  setupLookaside(db, 0, sqlite3GlobalConfig.szLookaside,
+                        sqlite3GlobalConfig.nLookaside);
+
 opendb_out:
   if( db ){
-    assert( db->mutex!=0 );
+    assert( db->mutex!=0 || isThreadsafe==0 || sqlite3GlobalConfig.bFullMutex==0 );
     sqlite3_mutex_leave(db->mutex);
   }
-  if( SQLITE_NOMEM==(rc = sqlite3_errcode(db)) ){
+  rc = sqlite3_errcode(db);
+  if( rc==SQLITE_NOMEM ){
     sqlite3_close(db);
     db = 0;
+  }else if( rc!=SQLITE_OK ){
+    db->magic = SQLITE_MAGIC_SICK;
   }
   *ppDb = db;
   return sqlite3ApiExit(0, rc);
@@ -75895,11 +84664,15 @@ SQLITE_API int sqlite3_open16(
 ){
   char const *zFilename8;   /* zFilename encoded in UTF-8 instead of UTF-16 */
   sqlite3_value *pVal;
-  int rc = SQLITE_NOMEM;
+  int rc;
 
   assert( zFilename );
   assert( ppDb );
   *ppDb = 0;
+#ifndef SQLITE_OMIT_AUTOINIT
+  rc = sqlite3_initialize();
+  if( rc ) return rc;
+#endif
   pVal = sqlite3ValueNew(0);
   sqlite3ValueSetStr(pVal, -1, zFilename, SQLITE_UTF16NATIVE, SQLITE_STATIC);
   zFilename8 = sqlite3ValueText(pVal, SQLITE_UTF8);
@@ -75907,13 +84680,11 @@ SQLITE_API int sqlite3_open16(
     rc = openDatabase(zFilename8, ppDb,
                       SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, 0);
     assert( *ppDb || rc==SQLITE_NOMEM );
-    if( rc==SQLITE_OK ){
-      rc = sqlite3_exec(*ppDb, "PRAGMA encoding = 'UTF-16'", 0, 0, 0);
-      if( rc!=SQLITE_OK ){
-        sqlite3_close(*ppDb);
-        *ppDb = 0;
-      }
+    if( rc==SQLITE_OK && !DbHasProperty(*ppDb, 0, DB_SchemaLoaded) ){
+      ENC(*ppDb) = SQLITE_UTF16NATIVE;
     }
+  }else{
+    rc = SQLITE_NOMEM;
   }
   sqlite3ValueFree(pVal);
 
@@ -75966,7 +84737,7 @@ SQLITE_API int sqlite3_create_collation_v2(
 */
 SQLITE_API int sqlite3_create_collation16(
   sqlite3* db, 
-  const char *zName, 
+  const void *zName,
   int enc, 
   void* pCtx,
   int(*xCompare)(void*,int,const void*,int,const void*)
@@ -75978,7 +84749,7 @@ SQLITE_API int sqlite3_create_collation16(
   zName8 = sqlite3Utf16to8(db, zName, -1);
   if( zName8 ){
     rc = createCollation(db, zName8, enc, pCtx, xCompare, 0);
-    sqlite3_free(zName8);
+    sqlite3DbFree(db, zName8);
   }
   rc = sqlite3ApiExit(db, rc);
   sqlite3_mutex_leave(db->mutex);
@@ -76023,6 +84794,7 @@ SQLITE_API int sqlite3_collation_needed16(
 #endif /* SQLITE_OMIT_UTF16 */
 
 #ifndef SQLITE_OMIT_GLOBALRECOVER
+#ifndef SQLITE_OMIT_DEPRECATED
 /*
 ** This function is now an anachronism. It used to be used to recover from a
 ** malloc() failure, but SQLite now does this automatically.
@@ -76031,6 +84803,7 @@ SQLITE_API int sqlite3_global_recover(void){
   return SQLITE_OK;
 }
 #endif
+#endif
 
 /*
 ** Test to see whether or not the database connection is in autocommit
@@ -76055,6 +84828,7 @@ SQLITE_PRIVATE int sqlite3Corrupt(void){
 }
 #endif
 
+#ifndef SQLITE_OMIT_DEPRECATED
 /*
 ** This is a convenience routine that makes sure that all thread-specific
 ** data for this thread has been deallocated.
@@ -76064,6 +84838,7 @@ SQLITE_PRIVATE int sqlite3Corrupt(void){
 */
 SQLITE_API void sqlite3_thread_cleanup(void){
 }
+#endif
 
 /*
 ** Return meta information about a specific column of a database table.
@@ -76079,7 +84854,7 @@ SQLITE_API int sqlite3_table_column_metadata(
   char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
   int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
   int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
-  int *pAutoinc               /* OUTPUT: True if colums is auto-increment */
+  int *pAutoinc               /* OUTPUT: True if column is auto-increment */
 ){
   int rc;
   char *zErrMsg = 0;
@@ -76094,8 +84869,8 @@ SQLITE_API int sqlite3_table_column_metadata(
   int autoinc = 0;
 
   /* Ensure the database schema has been loaded */
-  (void)sqlite3SafetyOn(db);
   sqlite3_mutex_enter(db->mutex);
+  (void)sqlite3SafetyOn(db);
   sqlite3BtreeEnterAll(db);
   rc = sqlite3Init(db, &zErrMsg);
   sqlite3BtreeLeaveAll(db);
@@ -76142,9 +84917,9 @@ SQLITE_API int sqlite3_table_column_metadata(
   if( pCol ){
     zDataType = pCol->zType;
     zCollSeq = pCol->zColl;
-    notnull = (pCol->notNull?1:0);
-    primarykey  = (pCol->isPrimKey?1:0);
-    autoinc = ((pTab->iPKey==iCol && pTab->autoInc)?1:0);
+    notnull = pCol->notNull!=0;
+    primarykey  = pCol->isPrimKey!=0;
+    autoinc = pTab->iPKey==iCol && (pTab->tabFlags & TF_Autoincrement)!=0;
   }else{
     zDataType = "INTEGER";
     primarykey = 1;
@@ -76167,12 +84942,13 @@ error_out:
   if( pAutoinc ) *pAutoinc = autoinc;
 
   if( SQLITE_OK==rc && !pTab ){
-    sqlite3SetString(&zErrMsg, "no such table column: ", zTableName, ".", 
-        zColumnName, 0);
+    sqlite3DbFree(db, zErrMsg);
+    zErrMsg = sqlite3MPrintf(db, "no such table column: %s.%s", zTableName,
+        zColumnName);
     rc = SQLITE_ERROR;
   }
   sqlite3Error(db, rc, (zErrMsg?"%s":0), zErrMsg);
-  sqlite3_free(zErrMsg);
+  sqlite3DbFree(db, zErrMsg);
   rc = sqlite3ApiExit(db, rc);
   sqlite3_mutex_leave(db->mutex);
   return rc;
@@ -76186,6 +84962,7 @@ SQLITE_API int sqlite3_sleep(int ms){
   sqlite3_vfs *pVfs;
   int rc;
   pVfs = sqlite3_vfs_find(0);
+  if( pVfs==0 ) return 0;
 
   /* This function works in milliseconds, but the underlying OsSleep() 
   ** API uses microseconds. Hence the 1000's.
@@ -76242,36 +85019,73 @@ SQLITE_API int sqlite3_file_control(sqlite3 *db, const char *zDbName, int op, vo
 ** Interface to the testing logic.
 */
 SQLITE_API int sqlite3_test_control(int op, ...){
-  va_list ap;
   int rc = 0;
+#ifndef SQLITE_OMIT_BUILTIN_TEST
+  va_list ap;
   va_start(ap, op);
   switch( op ){
-#ifndef SQLITE_OMIT_FAULTINJECTOR
-    case SQLITE_TESTCTRL_FAULT_CONFIG: {
-      int id = va_arg(ap, int);
-      int nDelay = va_arg(ap, int);
-      int nRepeat = va_arg(ap, int);
-      sqlite3FaultConfig(id, nDelay, nRepeat);
+
+    /*
+    ** Save the current state of the PRNG.
+    */
+    case SQLITE_TESTCTRL_PRNG_SAVE: {
+      sqlite3PrngSaveState();
+      break;
+    }
+
+    /*
+    ** Restore the state of the PRNG to the last state saved using
+    ** PRNG_SAVE.  If PRNG_SAVE has never before been called, then
+    ** this verb acts like PRNG_RESET.
+    */
+    case SQLITE_TESTCTRL_PRNG_RESTORE: {
+      sqlite3PrngRestoreState();
       break;
     }
-    case SQLITE_TESTCTRL_FAULT_FAILURES: {
-      int id = va_arg(ap, int);
-      rc = sqlite3FaultFailures(id);
+
+    /*
+    ** Reset the PRNG back to its uninitialized state.  The next call
+    ** to sqlite3_randomness() will reseed the PRNG using a single call
+    ** to the xRandomness method of the default VFS.
+    */
+    case SQLITE_TESTCTRL_PRNG_RESET: {
+      sqlite3PrngResetState();
       break;
     }
-    case SQLITE_TESTCTRL_FAULT_BENIGN_FAILURES: {
-      int id = va_arg(ap, int);
-      rc = sqlite3FaultBenignFailures(id);
+
+    /*
+    **  sqlite3_test_control(BITVEC_TEST, size, program)
+    **
+    ** Run a test against a Bitvec object of size.  The program argument
+    ** is an array of integers that defines the test.  Return -1 on a
+    ** memory allocation error, 0 on success, or non-zero for an error.
+    ** See the sqlite3BitvecBuiltinTest() for additional information.
+    */
+    case SQLITE_TESTCTRL_BITVEC_TEST: {
+      int sz = va_arg(ap, int);
+      int *aProg = va_arg(ap, int*);
+      rc = sqlite3BitvecBuiltinTest(sz, aProg);
       break;
     }
-    case SQLITE_TESTCTRL_FAULT_PENDING: {
-      int id = va_arg(ap, int);
-      rc = sqlite3FaultPending(id);
+
+    /*
+    **  sqlite3_test_control(BENIGN_MALLOC_HOOKS, xBegin, xEnd)
+    **
+    ** Register hooks to call to indicate which malloc() failures 
+    ** are benign.
+    */
+    case SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS: {
+      typedef void (*void_function)(void);
+      void_function xBenignBegin;
+      void_function xBenignEnd;
+      xBenignBegin = va_arg(ap, void_function);
+      xBenignEnd = va_arg(ap, void_function);
+      sqlite3BenignMallocHooks(xBenignBegin, xBenignEnd);
       break;
     }
-#endif /* SQLITE_OMIT_FAULTINJECTOR */
   }
   va_end(ap);
+#endif /* SQLITE_OMIT_BUILTIN_TEST */
   return rc;
 }
 
@@ -76551,7406 +85365,11663 @@ SQLITE_API int sqlite3_test_control(int op, ...){
 ** into a single segment.
 */
 
-#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
-
-#if defined(SQLITE_ENABLE_FTS3) && !defined(SQLITE_CORE)
-# define SQLITE_CORE 1
-#endif
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
+
+#if defined(SQLITE_ENABLE_FTS3) && !defined(SQLITE_CORE)
+# define SQLITE_CORE 1
+#endif
+
+
+/************** Include fts3_hash.h in the middle of fts3.c ******************/
+/************** Begin file fts3_hash.h ***************************************/
+/*
+** 2001 September 22
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This is the header file for the generic hash-table implemenation
+** used in SQLite.  We've modified it slightly to serve as a standalone
+** hash table implementation for the full-text indexing module.
+**
+*/
+#ifndef _FTS3_HASH_H_
+#define _FTS3_HASH_H_
+
+/* Forward declarations of structures. */
+typedef struct fts3Hash fts3Hash;
+typedef struct fts3HashElem fts3HashElem;
+
+/* A complete hash table is an instance of the following structure.
+** The internals of this structure are intended to be opaque -- client
+** code should not attempt to access or modify the fields of this structure
+** directly.  Change this structure only by using the routines below.
+** However, many of the "procedures" and "functions" for modifying and
+** accessing this structure are really macros, so we can't really make
+** this structure opaque.
+*/
+struct fts3Hash {
+  char keyClass;          /* HASH_INT, _POINTER, _STRING, _BINARY */
+  char copyKey;           /* True if copy of key made on insert */
+  int count;              /* Number of entries in this table */
+  fts3HashElem *first;    /* The first element of the array */
+  int htsize;             /* Number of buckets in the hash table */
+  struct _fts3ht {        /* the hash table */
+    int count;               /* Number of entries with this hash */
+    fts3HashElem *chain;     /* Pointer to first entry with this hash */
+  } *ht;
+};
+
+/* Each element in the hash table is an instance of the following 
+** structure.  All elements are stored on a single doubly-linked list.
+**
+** Again, this structure is intended to be opaque, but it can't really
+** be opaque because it is used by macros.
+*/
+struct fts3HashElem {
+  fts3HashElem *next, *prev; /* Next and previous elements in the table */
+  void *data;                /* Data associated with this element */
+  void *pKey; int nKey;      /* Key associated with this element */
+};
+
+/*
+** There are 2 different modes of operation for a hash table:
+**
+**   FTS3_HASH_STRING        pKey points to a string that is nKey bytes long
+**                           (including the null-terminator, if any).  Case
+**                           is respected in comparisons.
+**
+**   FTS3_HASH_BINARY        pKey points to binary data nKey bytes long. 
+**                           memcmp() is used to compare keys.
+**
+** A copy of the key is made if the copyKey parameter to fts3HashInit is 1.  
+*/
+#define FTS3_HASH_STRING    1
+#define FTS3_HASH_BINARY    2
+
+/*
+** Access routines.  To delete, insert a NULL pointer.
+*/
+SQLITE_PRIVATE void sqlite3Fts3HashInit(fts3Hash*, int keytype, int copyKey);
+SQLITE_PRIVATE void *sqlite3Fts3HashInsert(fts3Hash*, const void *pKey, int nKey, void *pData);
+SQLITE_PRIVATE void *sqlite3Fts3HashFind(const fts3Hash*, const void *pKey, int nKey);
+SQLITE_PRIVATE void sqlite3Fts3HashClear(fts3Hash*);
+
+/*
+** Shorthand for the functions above
+*/
+#define fts3HashInit   sqlite3Fts3HashInit
+#define fts3HashInsert sqlite3Fts3HashInsert
+#define fts3HashFind   sqlite3Fts3HashFind
+#define fts3HashClear  sqlite3Fts3HashClear
+
+/*
+** Macros for looping over all elements of a hash table.  The idiom is
+** like this:
+**
+**   fts3Hash h;
+**   fts3HashElem *p;
+**   ...
+**   for(p=fts3HashFirst(&h); p; p=fts3HashNext(p)){
+**     SomeStructure *pData = fts3HashData(p);
+**     // do something with pData
+**   }
+*/
+#define fts3HashFirst(H)  ((H)->first)
+#define fts3HashNext(E)   ((E)->next)
+#define fts3HashData(E)   ((E)->data)
+#define fts3HashKey(E)    ((E)->pKey)
+#define fts3HashKeysize(E) ((E)->nKey)
+
+/*
+** Number of entries in a hash table
+*/
+#define fts3HashCount(H)  ((H)->count)
+
+#endif /* _FTS3_HASH_H_ */
+
+/************** End of fts3_hash.h *******************************************/
+/************** Continuing where we left off in fts3.c ***********************/
+/************** Include fts3_tokenizer.h in the middle of fts3.c *************/
+/************** Begin file fts3_tokenizer.h **********************************/
+/*
+** 2006 July 10
+**
+** The author disclaims copyright to this source code.
+**
+*************************************************************************
+** Defines the interface to tokenizers used by fulltext-search.  There
+** are three basic components:
+**
+** sqlite3_tokenizer_module is a singleton defining the tokenizer
+** interface functions.  This is essentially the class structure for
+** tokenizers.
+**
+** sqlite3_tokenizer is used to define a particular tokenizer, perhaps
+** including customization information defined at creation time.
+**
+** sqlite3_tokenizer_cursor is generated by a tokenizer to generate
+** tokens from a particular input.
+*/
+#ifndef _FTS3_TOKENIZER_H_
+#define _FTS3_TOKENIZER_H_
+
+/* TODO(shess) Only used for SQLITE_OK and SQLITE_DONE at this time.
+** If tokenizers are to be allowed to call sqlite3_*() functions, then
+** we will need a way to register the API consistently.
+*/
+
+/*
+** Structures used by the tokenizer interface. When a new tokenizer
+** implementation is registered, the caller provides a pointer to
+** an sqlite3_tokenizer_module containing pointers to the callback
+** functions that make up an implementation.
+**
+** When an fts3 table is created, it passes any arguments passed to
+** the tokenizer clause of the CREATE VIRTUAL TABLE statement to the
+** sqlite3_tokenizer_module.xCreate() function of the requested tokenizer
+** implementation. The xCreate() function in turn returns an 
+** sqlite3_tokenizer structure representing the specific tokenizer to
+** be used for the fts3 table (customized by the tokenizer clause arguments).
+**
+** To tokenize an input buffer, the sqlite3_tokenizer_module.xOpen()
+** method is called. It returns an sqlite3_tokenizer_cursor object
+** that may be used to tokenize a specific input buffer based on
+** the tokenization rules supplied by a specific sqlite3_tokenizer
+** object.
+*/
+typedef struct sqlite3_tokenizer_module sqlite3_tokenizer_module;
+typedef struct sqlite3_tokenizer sqlite3_tokenizer;
+typedef struct sqlite3_tokenizer_cursor sqlite3_tokenizer_cursor;
+
+struct sqlite3_tokenizer_module {
+
+  /*
+  ** Structure version. Should always be set to 0.
+  */
+  int iVersion;
+
+  /*
+  ** Create a new tokenizer. The values in the argv[] array are the
+  ** arguments passed to the "tokenizer" clause of the CREATE VIRTUAL
+  ** TABLE statement that created the fts3 table. For example, if
+  ** the following SQL is executed:
+  **
+  **   CREATE .. USING fts3( ... , tokenizer  arg1 arg2)
+  **
+  ** then argc is set to 2, and the argv[] array contains pointers
+  ** to the strings "arg1" and "arg2".
+  **
+  ** This method should return either SQLITE_OK (0), or an SQLite error 
+  ** code. If SQLITE_OK is returned, then *ppTokenizer should be set
+  ** to point at the newly created tokenizer structure. The generic
+  ** sqlite3_tokenizer.pModule variable should not be initialised by
+  ** this callback. The caller will do so.
+  */
+  int (*xCreate)(
+    int argc,                           /* Size of argv array */
+    const char *const*argv,             /* Tokenizer argument strings */
+    sqlite3_tokenizer **ppTokenizer     /* OUT: Created tokenizer */
+  );
+
+  /*
+  ** Destroy an existing tokenizer. The fts3 module calls this method
+  ** exactly once for each successful call to xCreate().
+  */
+  int (*xDestroy)(sqlite3_tokenizer *pTokenizer);
+
+  /*
+  ** Create a tokenizer cursor to tokenize an input buffer. The caller
+  ** is responsible for ensuring that the input buffer remains valid
+  ** until the cursor is closed (using the xClose() method). 
+  */
+  int (*xOpen)(
+    sqlite3_tokenizer *pTokenizer,       /* Tokenizer object */
+    const char *pInput, int nBytes,      /* Input buffer */
+    sqlite3_tokenizer_cursor **ppCursor  /* OUT: Created tokenizer cursor */
+  );
+
+  /*
+  ** Destroy an existing tokenizer cursor. The fts3 module calls this 
+  ** method exactly once for each successful call to xOpen().
+  */
+  int (*xClose)(sqlite3_tokenizer_cursor *pCursor);
+
+  /*
+  ** Retrieve the next token from the tokenizer cursor pCursor. This
+  ** method should either return SQLITE_OK and set the values of the
+  ** "OUT" variables identified below, or SQLITE_DONE to indicate that
+  ** the end of the buffer has been reached, or an SQLite error code.
+  **
+  ** *ppToken should be set to point at a buffer containing the 
+  ** normalized version of the token (i.e. after any case-folding and/or
+  ** stemming has been performed). *pnBytes should be set to the length
+  ** of this buffer in bytes. The input text that generated the token is
+  ** identified by the byte offsets returned in *piStartOffset and
+  ** *piEndOffset.
+  **
+  ** The buffer *ppToken is set to point at is managed by the tokenizer
+  ** implementation. It is only required to be valid until the next call
+  ** to xNext() or xClose(). 
+  */
+  /* TODO(shess) current implementation requires pInput to be
+  ** nul-terminated.  This should either be fixed, or pInput/nBytes
+  ** should be converted to zInput.
+  */
+  int (*xNext)(
+    sqlite3_tokenizer_cursor *pCursor,   /* Tokenizer cursor */
+    const char **ppToken, int *pnBytes,  /* OUT: Normalized text for token */
+    int *piStartOffset,  /* OUT: Byte offset of token in input buffer */
+    int *piEndOffset,    /* OUT: Byte offset of end of token in input buffer */
+    int *piPosition      /* OUT: Number of tokens returned before this one */
+  );
+};
+
+struct sqlite3_tokenizer {
+  const sqlite3_tokenizer_module *pModule;  /* The module for this tokenizer */
+  /* Tokenizer implementations will typically add additional fields */
+};
+
+struct sqlite3_tokenizer_cursor {
+  sqlite3_tokenizer *pTokenizer;       /* Tokenizer for this cursor. */
+  /* Tokenizer implementations will typically add additional fields */
+};
+
+#endif /* _FTS3_TOKENIZER_H_ */
+
+/************** End of fts3_tokenizer.h **************************************/
+/************** Continuing where we left off in fts3.c ***********************/
+#ifndef SQLITE_CORE 
+  SQLITE_EXTENSION_INIT1
+#endif
+
+
+/* TODO(shess) MAN, this thing needs some refactoring.  At minimum, it
+** would be nice to order the file better, perhaps something along the
+** lines of:
+**
+**  - utility functions
+**  - table setup functions
+**  - table update functions
+**  - table query functions
+**
+** Put the query functions last because they're likely to reference
+** typedefs or functions from the table update section.
+*/
+
+#if 0
+# define FTSTRACE(A)  printf A; fflush(stdout)
+#else
+# define FTSTRACE(A)
+#endif
+
+/*
+** Default span for NEAR operators.
+*/
+#define SQLITE_FTS3_DEFAULT_NEAR_PARAM 10
+
+/* It is not safe to call isspace(), tolower(), or isalnum() on
+** hi-bit-set characters.  This is the same solution used in the
+** tokenizer.
+*/
+/* TODO(shess) The snippet-generation code should be using the
+** tokenizer-generated tokens rather than doing its own local
+** tokenization.
+*/
+/* TODO(shess) Is __isascii() a portable version of (c&0x80)==0? */
+static int safe_isspace(char c){
+  return (c&0x80)==0 ? isspace(c) : 0;
+}
+static int safe_tolower(char c){
+  return (c&0x80)==0 ? tolower(c) : c;
+}
+static int safe_isalnum(char c){
+  return (c&0x80)==0 ? isalnum(c) : 0;
+}
+
+typedef enum DocListType {
+  DL_DOCIDS,              /* docids only */
+  DL_POSITIONS,           /* docids + positions */
+  DL_POSITIONS_OFFSETS    /* docids + positions + offsets */
+} DocListType;
+
+/*
+** By default, only positions and not offsets are stored in the doclists.
+** To change this so that offsets are stored too, compile with
+**
+**          -DDL_DEFAULT=DL_POSITIONS_OFFSETS
+**
+** If DL_DEFAULT is set to DL_DOCIDS, your table can only be inserted
+** into (no deletes or updates).
+*/
+#ifndef DL_DEFAULT
+# define DL_DEFAULT DL_POSITIONS
+#endif
+
+enum {
+  POS_END = 0,        /* end of this position list */
+  POS_COLUMN,         /* followed by new column number */
+  POS_BASE
+};
+
+/* MERGE_COUNT controls how often we merge segments (see comment at
+** top of file).
+*/
+#define MERGE_COUNT 16
+
+/* utility functions */
+
+/* CLEAR() and SCRAMBLE() abstract memset() on a pointer to a single
+** record to prevent errors of the form:
+**
+** my_function(SomeType *b){
+**   memset(b, '\0', sizeof(b));  // sizeof(b)!=sizeof(*b)
+** }
+*/
+/* TODO(shess) Obvious candidates for a header file. */
+#define CLEAR(b) memset(b, '\0', sizeof(*(b)))
+
+#ifndef NDEBUG
+#  define SCRAMBLE(b) memset(b, 0x55, sizeof(*(b)))
+#else
+#  define SCRAMBLE(b)
+#endif
+
+/* We may need up to VARINT_MAX bytes to store an encoded 64-bit integer. */
+#define VARINT_MAX 10
+
+/* Write a 64-bit variable-length integer to memory starting at p[0].
+ * The length of data written will be between 1 and VARINT_MAX bytes.
+ * The number of bytes written is returned. */
+static int fts3PutVarint(char *p, sqlite_int64 v){
+  unsigned char *q = (unsigned char *) p;
+  sqlite_uint64 vu = v;
+  do{
+    *q++ = (unsigned char) ((vu & 0x7f) | 0x80);
+    vu >>= 7;
+  }while( vu!=0 );
+  q[-1] &= 0x7f;  /* turn off high bit in final byte */
+  assert( q - (unsigned char *)p <= VARINT_MAX );
+  return (int) (q - (unsigned char *)p);
+}
+
+/* Read a 64-bit variable-length integer from memory starting at p[0].
+ * Return the number of bytes read, or 0 on error.
+ * The value is stored in *v. */
+static int fts3GetVarint(const char *p, sqlite_int64 *v){
+  const unsigned char *q = (const unsigned char *) p;
+  sqlite_uint64 x = 0, y = 1;
+  while( (*q & 0x80) == 0x80 ){
+    x += y * (*q++ & 0x7f);
+    y <<= 7;
+    if( q - (unsigned char *)p >= VARINT_MAX ){  /* bad data */
+      assert( 0 );
+      return 0;
+    }
+  }
+  x += y * (*q++);
+  *v = (sqlite_int64) x;
+  return (int) (q - (unsigned char *)p);
+}
+
+static int fts3GetVarint32(const char *p, int *pi){
+ sqlite_int64 i;
+ int ret = fts3GetVarint(p, &i);
+ *pi = (int) i;
+ assert( *pi==i );
+ return ret;
+}
+
+/*******************************************************************/
+/* DataBuffer is used to collect data into a buffer in piecemeal
+** fashion.  It implements the usual distinction between amount of
+** data currently stored (nData) and buffer capacity (nCapacity).
+**
+** dataBufferInit - create a buffer with given initial capacity.
+** dataBufferReset - forget buffer's data, retaining capacity.
+** dataBufferDestroy - free buffer's data.
+** dataBufferSwap - swap contents of two buffers.
+** dataBufferExpand - expand capacity without adding data.
+** dataBufferAppend - append data.
+** dataBufferAppend2 - append two pieces of data at once.
+** dataBufferReplace - replace buffer's data.
+*/
+typedef struct DataBuffer {
+  char *pData;          /* Pointer to malloc'ed buffer. */
+  int nCapacity;        /* Size of pData buffer. */
+  int nData;            /* End of data loaded into pData. */
+} DataBuffer;
+
+static void dataBufferInit(DataBuffer *pBuffer, int nCapacity){
+  assert( nCapacity>=0 );
+  pBuffer->nData = 0;
+  pBuffer->nCapacity = nCapacity;
+  pBuffer->pData = nCapacity==0 ? NULL : sqlite3_malloc(nCapacity);
+}
+static void dataBufferReset(DataBuffer *pBuffer){
+  pBuffer->nData = 0;
+}
+static void dataBufferDestroy(DataBuffer *pBuffer){
+  if( pBuffer->pData!=NULL ) sqlite3_free(pBuffer->pData);
+  SCRAMBLE(pBuffer);
+}
+static void dataBufferSwap(DataBuffer *pBuffer1, DataBuffer *pBuffer2){
+  DataBuffer tmp = *pBuffer1;
+  *pBuffer1 = *pBuffer2;
+  *pBuffer2 = tmp;
+}
+static void dataBufferExpand(DataBuffer *pBuffer, int nAddCapacity){
+  assert( nAddCapacity>0 );
+  /* TODO(shess) Consider expanding more aggressively.  Note that the
+  ** underlying malloc implementation may take care of such things for
+  ** us already.
+  */
+  if( pBuffer->nData+nAddCapacity>pBuffer->nCapacity ){
+    pBuffer->nCapacity = pBuffer->nData+nAddCapacity;
+    pBuffer->pData = sqlite3_realloc(pBuffer->pData, pBuffer->nCapacity);
+  }
+}
+static void dataBufferAppend(DataBuffer *pBuffer,
+                             const char *pSource, int nSource){
+  assert( nSource>0 && pSource!=NULL );
+  dataBufferExpand(pBuffer, nSource);
+  memcpy(pBuffer->pData+pBuffer->nData, pSource, nSource);
+  pBuffer->nData += nSource;
+}
+static void dataBufferAppend2(DataBuffer *pBuffer,
+                              const char *pSource1, int nSource1,
+                              const char *pSource2, int nSource2){
+  assert( nSource1>0 && pSource1!=NULL );
+  assert( nSource2>0 && pSource2!=NULL );
+  dataBufferExpand(pBuffer, nSource1+nSource2);
+  memcpy(pBuffer->pData+pBuffer->nData, pSource1, nSource1);
+  memcpy(pBuffer->pData+pBuffer->nData+nSource1, pSource2, nSource2);
+  pBuffer->nData += nSource1+nSource2;
+}
+static void dataBufferReplace(DataBuffer *pBuffer,
+                              const char *pSource, int nSource){
+  dataBufferReset(pBuffer);
+  dataBufferAppend(pBuffer, pSource, nSource);
+}
+
+/* StringBuffer is a null-terminated version of DataBuffer. */
+typedef struct StringBuffer {
+  DataBuffer b;            /* Includes null terminator. */
+} StringBuffer;
+
+static void initStringBuffer(StringBuffer *sb){
+  dataBufferInit(&sb->b, 100);
+  dataBufferReplace(&sb->b, "", 1);
+}
+static int stringBufferLength(StringBuffer *sb){
+  return sb->b.nData-1;
+}
+static char *stringBufferData(StringBuffer *sb){
+  return sb->b.pData;
+}
+static void stringBufferDestroy(StringBuffer *sb){
+  dataBufferDestroy(&sb->b);
+}
+
+static void nappend(StringBuffer *sb, const char *zFrom, int nFrom){
+  assert( sb->b.nData>0 );
+  if( nFrom>0 ){
+    sb->b.nData--;
+    dataBufferAppend2(&sb->b, zFrom, nFrom, "", 1);
+  }
+}
+static void append(StringBuffer *sb, const char *zFrom){
+  nappend(sb, zFrom, strlen(zFrom));
+}
+
+/* Append a list of strings separated by commas. */
+static void appendList(StringBuffer *sb, int nString, char **azString){
+  int i;
+  for(i=0; i0 ) append(sb, ", ");
+    append(sb, azString[i]);
+  }
+}
+
+static int endsInWhiteSpace(StringBuffer *p){
+  return stringBufferLength(p)>0 &&
+    safe_isspace(stringBufferData(p)[stringBufferLength(p)-1]);
+}
+
+/* If the StringBuffer ends in something other than white space, add a
+** single space character to the end.
+*/
+static void appendWhiteSpace(StringBuffer *p){
+  if( stringBufferLength(p)==0 ) return;
+  if( !endsInWhiteSpace(p) ) append(p, " ");
+}
+
+/* Remove white space from the end of the StringBuffer */
+static void trimWhiteSpace(StringBuffer *p){
+  while( endsInWhiteSpace(p) ){
+    p->b.pData[--p->b.nData-1] = '\0';
+  }
+}
+
+/*******************************************************************/
+/* DLReader is used to read document elements from a doclist.  The
+** current docid is cached, so dlrDocid() is fast.  DLReader does not
+** own the doclist buffer.
+**
+** dlrAtEnd - true if there's no more data to read.
+** dlrDocid - docid of current document.
+** dlrDocData - doclist data for current document (including docid).
+** dlrDocDataBytes - length of same.
+** dlrAllDataBytes - length of all remaining data.
+** dlrPosData - position data for current document.
+** dlrPosDataLen - length of pos data for current document (incl POS_END).
+** dlrStep - step to current document.
+** dlrInit - initial for doclist of given type against given data.
+** dlrDestroy - clean up.
+**
+** Expected usage is something like:
+**
+**   DLReader reader;
+**   dlrInit(&reader, pData, nData);
+**   while( !dlrAtEnd(&reader) ){
+**     // calls to dlrDocid() and kin.
+**     dlrStep(&reader);
+**   }
+**   dlrDestroy(&reader);
+*/
+typedef struct DLReader {
+  DocListType iType;
+  const char *pData;
+  int nData;
+
+  sqlite_int64 iDocid;
+  int nElement;
+} DLReader;
+
+static int dlrAtEnd(DLReader *pReader){
+  assert( pReader->nData>=0 );
+  return pReader->nData==0;
+}
+static sqlite_int64 dlrDocid(DLReader *pReader){
+  assert( !dlrAtEnd(pReader) );
+  return pReader->iDocid;
+}
+static const char *dlrDocData(DLReader *pReader){
+  assert( !dlrAtEnd(pReader) );
+  return pReader->pData;
+}
+static int dlrDocDataBytes(DLReader *pReader){
+  assert( !dlrAtEnd(pReader) );
+  return pReader->nElement;
+}
+static int dlrAllDataBytes(DLReader *pReader){
+  assert( !dlrAtEnd(pReader) );
+  return pReader->nData;
+}
+/* TODO(shess) Consider adding a field to track iDocid varint length
+** to make these two functions faster.  This might matter (a tiny bit)
+** for queries.
+*/
+static const char *dlrPosData(DLReader *pReader){
+  sqlite_int64 iDummy;
+  int n = fts3GetVarint(pReader->pData, &iDummy);
+  assert( !dlrAtEnd(pReader) );
+  return pReader->pData+n;
+}
+static int dlrPosDataLen(DLReader *pReader){
+  sqlite_int64 iDummy;
+  int n = fts3GetVarint(pReader->pData, &iDummy);
+  assert( !dlrAtEnd(pReader) );
+  return pReader->nElement-n;
+}
+static void dlrStep(DLReader *pReader){
+  assert( !dlrAtEnd(pReader) );
+
+  /* Skip past current doclist element. */
+  assert( pReader->nElement<=pReader->nData );
+  pReader->pData += pReader->nElement;
+  pReader->nData -= pReader->nElement;
+
+  /* If there is more data, read the next doclist element. */
+  if( pReader->nData!=0 ){
+    sqlite_int64 iDocidDelta;
+    int iDummy, n = fts3GetVarint(pReader->pData, &iDocidDelta);
+    pReader->iDocid += iDocidDelta;
+    if( pReader->iType>=DL_POSITIONS ){
+      assert( nnData );
+      while( 1 ){
+        n += fts3GetVarint32(pReader->pData+n, &iDummy);
+        assert( n<=pReader->nData );
+        if( iDummy==POS_END ) break;
+        if( iDummy==POS_COLUMN ){
+          n += fts3GetVarint32(pReader->pData+n, &iDummy);
+          assert( nnData );
+        }else if( pReader->iType==DL_POSITIONS_OFFSETS ){
+          n += fts3GetVarint32(pReader->pData+n, &iDummy);
+          n += fts3GetVarint32(pReader->pData+n, &iDummy);
+          assert( nnData );
+        }
+      }
+    }
+    pReader->nElement = n;
+    assert( pReader->nElement<=pReader->nData );
+  }
+}
+static void dlrInit(DLReader *pReader, DocListType iType,
+                    const char *pData, int nData){
+  assert( pData!=NULL && nData!=0 );
+  pReader->iType = iType;
+  pReader->pData = pData;
+  pReader->nData = nData;
+  pReader->nElement = 0;
+  pReader->iDocid = 0;
+
+  /* Load the first element's data.  There must be a first element. */
+  dlrStep(pReader);
+}
+static void dlrDestroy(DLReader *pReader){
+  SCRAMBLE(pReader);
+}
+
+#ifndef NDEBUG
+/* Verify that the doclist can be validly decoded.  Also returns the
+** last docid found because it is convenient in other assertions for
+** DLWriter.
+*/
+static void docListValidate(DocListType iType, const char *pData, int nData,
+                            sqlite_int64 *pLastDocid){
+  sqlite_int64 iPrevDocid = 0;
+  assert( nData>0 );
+  assert( pData!=0 );
+  assert( pData+nData>pData );
+  while( nData!=0 ){
+    sqlite_int64 iDocidDelta;
+    int n = fts3GetVarint(pData, &iDocidDelta);
+    iPrevDocid += iDocidDelta;
+    if( iType>DL_DOCIDS ){
+      int iDummy;
+      while( 1 ){
+        n += fts3GetVarint32(pData+n, &iDummy);
+        if( iDummy==POS_END ) break;
+        if( iDummy==POS_COLUMN ){
+          n += fts3GetVarint32(pData+n, &iDummy);
+        }else if( iType>DL_POSITIONS ){
+          n += fts3GetVarint32(pData+n, &iDummy);
+          n += fts3GetVarint32(pData+n, &iDummy);
+        }
+        assert( n<=nData );
+      }
+    }
+    assert( n<=nData );
+    pData += n;
+    nData -= n;
+  }
+  if( pLastDocid ) *pLastDocid = iPrevDocid;
+}
+#define ASSERT_VALID_DOCLIST(i, p, n, o) docListValidate(i, p, n, o)
+#else
+#define ASSERT_VALID_DOCLIST(i, p, n, o) assert( 1 )
+#endif
+
+/*******************************************************************/
+/* DLWriter is used to write doclist data to a DataBuffer.  DLWriter
+** always appends to the buffer and does not own it.
+**
+** dlwInit - initialize to write a given type doclistto a buffer.
+** dlwDestroy - clear the writer's memory.  Does not free buffer.
+** dlwAppend - append raw doclist data to buffer.
+** dlwCopy - copy next doclist from reader to writer.
+** dlwAdd - construct doclist element and append to buffer.
+**    Only apply dlwAdd() to DL_DOCIDS doclists (else use PLWriter).
+*/
+typedef struct DLWriter {
+  DocListType iType;
+  DataBuffer *b;
+  sqlite_int64 iPrevDocid;
+#ifndef NDEBUG
+  int has_iPrevDocid;
+#endif
+} DLWriter;
+
+static void dlwInit(DLWriter *pWriter, DocListType iType, DataBuffer *b){
+  pWriter->b = b;
+  pWriter->iType = iType;
+  pWriter->iPrevDocid = 0;
+#ifndef NDEBUG
+  pWriter->has_iPrevDocid = 0;
+#endif
+}
+static void dlwDestroy(DLWriter *pWriter){
+  SCRAMBLE(pWriter);
+}
+/* iFirstDocid is the first docid in the doclist in pData.  It is
+** needed because pData may point within a larger doclist, in which
+** case the first item would be delta-encoded.
+**
+** iLastDocid is the final docid in the doclist in pData.  It is
+** needed to create the new iPrevDocid for future delta-encoding.  The
+** code could decode the passed doclist to recreate iLastDocid, but
+** the only current user (docListMerge) already has decoded this
+** information.
+*/
+/* TODO(shess) This has become just a helper for docListMerge.
+** Consider a refactor to make this cleaner.
+*/
+static void dlwAppend(DLWriter *pWriter,
+                      const char *pData, int nData,
+                      sqlite_int64 iFirstDocid, sqlite_int64 iLastDocid){
+  sqlite_int64 iDocid = 0;
+  char c[VARINT_MAX];
+  int nFirstOld, nFirstNew;     /* Old and new varint len of first docid. */
+#ifndef NDEBUG
+  sqlite_int64 iLastDocidDelta;
+#endif
+
+  /* Recode the initial docid as delta from iPrevDocid. */
+  nFirstOld = fts3GetVarint(pData, &iDocid);
+  assert( nFirstOldiType==DL_DOCIDS) );
+  nFirstNew = fts3PutVarint(c, iFirstDocid-pWriter->iPrevDocid);
+
+  /* Verify that the incoming doclist is valid AND that it ends with
+  ** the expected docid.  This is essential because we'll trust this
+  ** docid in future delta-encoding.
+  */
+  ASSERT_VALID_DOCLIST(pWriter->iType, pData, nData, &iLastDocidDelta);
+  assert( iLastDocid==iFirstDocid-iDocid+iLastDocidDelta );
+
+  /* Append recoded initial docid and everything else.  Rest of docids
+  ** should have been delta-encoded from previous initial docid.
+  */
+  if( nFirstOldb, c, nFirstNew,
+                      pData+nFirstOld, nData-nFirstOld);
+  }else{
+    dataBufferAppend(pWriter->b, c, nFirstNew);
+  }
+  pWriter->iPrevDocid = iLastDocid;
+}
+static void dlwCopy(DLWriter *pWriter, DLReader *pReader){
+  dlwAppend(pWriter, dlrDocData(pReader), dlrDocDataBytes(pReader),
+            dlrDocid(pReader), dlrDocid(pReader));
+}
+static void dlwAdd(DLWriter *pWriter, sqlite_int64 iDocid){
+  char c[VARINT_MAX];
+  int n = fts3PutVarint(c, iDocid-pWriter->iPrevDocid);
+
+  /* Docids must ascend. */
+  assert( !pWriter->has_iPrevDocid || iDocid>pWriter->iPrevDocid );
+  assert( pWriter->iType==DL_DOCIDS );
+
+  dataBufferAppend(pWriter->b, c, n);
+  pWriter->iPrevDocid = iDocid;
+#ifndef NDEBUG
+  pWriter->has_iPrevDocid = 1;
+#endif
+}
+
+/*******************************************************************/
+/* PLReader is used to read data from a document's position list.  As
+** the caller steps through the list, data is cached so that varints
+** only need to be decoded once.
+**
+** plrInit, plrDestroy - create/destroy a reader.
+** plrColumn, plrPosition, plrStartOffset, plrEndOffset - accessors
+** plrAtEnd - at end of stream, only call plrDestroy once true.
+** plrStep - step to the next element.
+*/
+typedef struct PLReader {
+  /* These refer to the next position's data.  nData will reach 0 when
+  ** reading the last position, so plrStep() signals EOF by setting
+  ** pData to NULL.
+  */
+  const char *pData;
+  int nData;
+
+  DocListType iType;
+  int iColumn;         /* the last column read */
+  int iPosition;       /* the last position read */
+  int iStartOffset;    /* the last start offset read */
+  int iEndOffset;      /* the last end offset read */
+} PLReader;
+
+static int plrAtEnd(PLReader *pReader){
+  return pReader->pData==NULL;
+}
+static int plrColumn(PLReader *pReader){
+  assert( !plrAtEnd(pReader) );
+  return pReader->iColumn;
+}
+static int plrPosition(PLReader *pReader){
+  assert( !plrAtEnd(pReader) );
+  return pReader->iPosition;
+}
+static int plrStartOffset(PLReader *pReader){
+  assert( !plrAtEnd(pReader) );
+  return pReader->iStartOffset;
+}
+static int plrEndOffset(PLReader *pReader){
+  assert( !plrAtEnd(pReader) );
+  return pReader->iEndOffset;
+}
+static void plrStep(PLReader *pReader){
+  int i, n;
+
+  assert( !plrAtEnd(pReader) );
+
+  if( pReader->nData==0 ){
+    pReader->pData = NULL;
+    return;
+  }
+
+  n = fts3GetVarint32(pReader->pData, &i);
+  if( i==POS_COLUMN ){
+    n += fts3GetVarint32(pReader->pData+n, &pReader->iColumn);
+    pReader->iPosition = 0;
+    pReader->iStartOffset = 0;
+    n += fts3GetVarint32(pReader->pData+n, &i);
+  }
+  /* Should never see adjacent column changes. */
+  assert( i!=POS_COLUMN );
+
+  if( i==POS_END ){
+    pReader->nData = 0;
+    pReader->pData = NULL;
+    return;
+  }
+
+  pReader->iPosition += i-POS_BASE;
+  if( pReader->iType==DL_POSITIONS_OFFSETS ){
+    n += fts3GetVarint32(pReader->pData+n, &i);
+    pReader->iStartOffset += i;
+    n += fts3GetVarint32(pReader->pData+n, &i);
+    pReader->iEndOffset = pReader->iStartOffset+i;
+  }
+  assert( n<=pReader->nData );
+  pReader->pData += n;
+  pReader->nData -= n;
+}
+
+static void plrInit(PLReader *pReader, DLReader *pDLReader){
+  pReader->pData = dlrPosData(pDLReader);
+  pReader->nData = dlrPosDataLen(pDLReader);
+  pReader->iType = pDLReader->iType;
+  pReader->iColumn = 0;
+  pReader->iPosition = 0;
+  pReader->iStartOffset = 0;
+  pReader->iEndOffset = 0;
+  plrStep(pReader);
+}
+static void plrDestroy(PLReader *pReader){
+  SCRAMBLE(pReader);
+}
+
+/*******************************************************************/
+/* PLWriter is used in constructing a document's position list.  As a
+** convenience, if iType is DL_DOCIDS, PLWriter becomes a no-op.
+** PLWriter writes to the associated DLWriter's buffer.
+**
+** plwInit - init for writing a document's poslist.
+** plwDestroy - clear a writer.
+** plwAdd - append position and offset information.
+** plwCopy - copy next position's data from reader to writer.
+** plwTerminate - add any necessary doclist terminator.
+**
+** Calling plwAdd() after plwTerminate() may result in a corrupt
+** doclist.
+*/
+/* TODO(shess) Until we've written the second item, we can cache the
+** first item's information.  Then we'd have three states:
+**
+** - initialized with docid, no positions.
+** - docid and one position.
+** - docid and multiple positions.
+**
+** Only the last state needs to actually write to dlw->b, which would
+** be an improvement in the DLCollector case.
+*/
+typedef struct PLWriter {
+  DLWriter *dlw;
+
+  int iColumn;    /* the last column written */
+  int iPos;       /* the last position written */
+  int iOffset;    /* the last start offset written */
+} PLWriter;
+
+/* TODO(shess) In the case where the parent is reading these values
+** from a PLReader, we could optimize to a copy if that PLReader has
+** the same type as pWriter.
+*/
+static void plwAdd(PLWriter *pWriter, int iColumn, int iPos,
+                   int iStartOffset, int iEndOffset){
+  /* Worst-case space for POS_COLUMN, iColumn, iPosDelta,
+  ** iStartOffsetDelta, and iEndOffsetDelta.
+  */
+  char c[5*VARINT_MAX];
+  int n = 0;
+
+  /* Ban plwAdd() after plwTerminate(). */
+  assert( pWriter->iPos!=-1 );
+
+  if( pWriter->dlw->iType==DL_DOCIDS ) return;
+
+  if( iColumn!=pWriter->iColumn ){
+    n += fts3PutVarint(c+n, POS_COLUMN);
+    n += fts3PutVarint(c+n, iColumn);
+    pWriter->iColumn = iColumn;
+    pWriter->iPos = 0;
+    pWriter->iOffset = 0;
+  }
+  assert( iPos>=pWriter->iPos );
+  n += fts3PutVarint(c+n, POS_BASE+(iPos-pWriter->iPos));
+  pWriter->iPos = iPos;
+  if( pWriter->dlw->iType==DL_POSITIONS_OFFSETS ){
+    assert( iStartOffset>=pWriter->iOffset );
+    n += fts3PutVarint(c+n, iStartOffset-pWriter->iOffset);
+    pWriter->iOffset = iStartOffset;
+    assert( iEndOffset>=iStartOffset );
+    n += fts3PutVarint(c+n, iEndOffset-iStartOffset);
+  }
+  dataBufferAppend(pWriter->dlw->b, c, n);
+}
+static void plwCopy(PLWriter *pWriter, PLReader *pReader){
+  plwAdd(pWriter, plrColumn(pReader), plrPosition(pReader),
+         plrStartOffset(pReader), plrEndOffset(pReader));
+}
+static void plwInit(PLWriter *pWriter, DLWriter *dlw, sqlite_int64 iDocid){
+  char c[VARINT_MAX];
+  int n;
+
+  pWriter->dlw = dlw;
+
+  /* Docids must ascend. */
+  assert( !pWriter->dlw->has_iPrevDocid || iDocid>pWriter->dlw->iPrevDocid );
+  n = fts3PutVarint(c, iDocid-pWriter->dlw->iPrevDocid);
+  dataBufferAppend(pWriter->dlw->b, c, n);
+  pWriter->dlw->iPrevDocid = iDocid;
+#ifndef NDEBUG
+  pWriter->dlw->has_iPrevDocid = 1;
+#endif
+
+  pWriter->iColumn = 0;
+  pWriter->iPos = 0;
+  pWriter->iOffset = 0;
+}
+/* TODO(shess) Should plwDestroy() also terminate the doclist?  But
+** then plwDestroy() would no longer be just a destructor, it would
+** also be doing work, which isn't consistent with the overall idiom.
+** Another option would be for plwAdd() to always append any necessary
+** terminator, so that the output is always correct.  But that would
+** add incremental work to the common case with the only benefit being
+** API elegance.  Punt for now.
+*/
+static void plwTerminate(PLWriter *pWriter){
+  if( pWriter->dlw->iType>DL_DOCIDS ){
+    char c[VARINT_MAX];
+    int n = fts3PutVarint(c, POS_END);
+    dataBufferAppend(pWriter->dlw->b, c, n);
+  }
+#ifndef NDEBUG
+  /* Mark as terminated for assert in plwAdd(). */
+  pWriter->iPos = -1;
+#endif
+}
+static void plwDestroy(PLWriter *pWriter){
+  SCRAMBLE(pWriter);
+}
+
+/*******************************************************************/
+/* DLCollector wraps PLWriter and DLWriter to provide a
+** dynamically-allocated doclist area to use during tokenization.
+**
+** dlcNew - malloc up and initialize a collector.
+** dlcDelete - destroy a collector and all contained items.
+** dlcAddPos - append position and offset information.
+** dlcAddDoclist - add the collected doclist to the given buffer.
+** dlcNext - terminate the current document and open another.
+*/
+typedef struct DLCollector {
+  DataBuffer b;
+  DLWriter dlw;
+  PLWriter plw;
+} DLCollector;
+
+/* TODO(shess) This could also be done by calling plwTerminate() and
+** dataBufferAppend().  I tried that, expecting nominal performance
+** differences, but it seemed to pretty reliably be worth 1% to code
+** it this way.  I suspect it is the incremental malloc overhead (some
+** percentage of the plwTerminate() calls will cause a realloc), so
+** this might be worth revisiting if the DataBuffer implementation
+** changes.
+*/
+static void dlcAddDoclist(DLCollector *pCollector, DataBuffer *b){
+  if( pCollector->dlw.iType>DL_DOCIDS ){
+    char c[VARINT_MAX];
+    int n = fts3PutVarint(c, POS_END);
+    dataBufferAppend2(b, pCollector->b.pData, pCollector->b.nData, c, n);
+  }else{
+    dataBufferAppend(b, pCollector->b.pData, pCollector->b.nData);
+  }
+}
+static void dlcNext(DLCollector *pCollector, sqlite_int64 iDocid){
+  plwTerminate(&pCollector->plw);
+  plwDestroy(&pCollector->plw);
+  plwInit(&pCollector->plw, &pCollector->dlw, iDocid);
+}
+static void dlcAddPos(DLCollector *pCollector, int iColumn, int iPos,
+                      int iStartOffset, int iEndOffset){
+  plwAdd(&pCollector->plw, iColumn, iPos, iStartOffset, iEndOffset);
+}
+
+static DLCollector *dlcNew(sqlite_int64 iDocid, DocListType iType){
+  DLCollector *pCollector = sqlite3_malloc(sizeof(DLCollector));
+  dataBufferInit(&pCollector->b, 0);
+  dlwInit(&pCollector->dlw, iType, &pCollector->b);
+  plwInit(&pCollector->plw, &pCollector->dlw, iDocid);
+  return pCollector;
+}
+static void dlcDelete(DLCollector *pCollector){
+  plwDestroy(&pCollector->plw);
+  dlwDestroy(&pCollector->dlw);
+  dataBufferDestroy(&pCollector->b);
+  SCRAMBLE(pCollector);
+  sqlite3_free(pCollector);
+}
+
+
+/* Copy the doclist data of iType in pData/nData into *out, trimming
+** unnecessary data as we go.  Only columns matching iColumn are
+** copied, all columns copied if iColumn is -1.  Elements with no
+** matching columns are dropped.  The output is an iOutType doclist.
+*/
+/* NOTE(shess) This code is only valid after all doclists are merged.
+** If this is run before merges, then doclist items which represent
+** deletion will be trimmed, and will thus not effect a deletion
+** during the merge.
+*/
+static void docListTrim(DocListType iType, const char *pData, int nData,
+                        int iColumn, DocListType iOutType, DataBuffer *out){
+  DLReader dlReader;
+  DLWriter dlWriter;
+
+  assert( iOutType<=iType );
+
+  dlrInit(&dlReader, iType, pData, nData);
+  dlwInit(&dlWriter, iOutType, out);
+
+  while( !dlrAtEnd(&dlReader) ){
+    PLReader plReader;
+    PLWriter plWriter;
+    int match = 0;
+
+    plrInit(&plReader, &dlReader);
+
+    while( !plrAtEnd(&plReader) ){
+      if( iColumn==-1 || plrColumn(&plReader)==iColumn ){
+        if( !match ){
+          plwInit(&plWriter, &dlWriter, dlrDocid(&dlReader));
+          match = 1;
+        }
+        plwAdd(&plWriter, plrColumn(&plReader), plrPosition(&plReader),
+               plrStartOffset(&plReader), plrEndOffset(&plReader));
+      }
+      plrStep(&plReader);
+    }
+    if( match ){
+      plwTerminate(&plWriter);
+      plwDestroy(&plWriter);
+    }
+
+    plrDestroy(&plReader);
+    dlrStep(&dlReader);
+  }
+  dlwDestroy(&dlWriter);
+  dlrDestroy(&dlReader);
+}
+
+/* Used by docListMerge() to keep doclists in the ascending order by
+** docid, then ascending order by age (so the newest comes first).
+*/
+typedef struct OrderedDLReader {
+  DLReader *pReader;
+
+  /* TODO(shess) If we assume that docListMerge pReaders is ordered by
+  ** age (which we do), then we could use pReader comparisons to break
+  ** ties.
+  */
+  int idx;
+} OrderedDLReader;
+
+/* Order eof to end, then by docid asc, idx desc. */
+static int orderedDLReaderCmp(OrderedDLReader *r1, OrderedDLReader *r2){
+  if( dlrAtEnd(r1->pReader) ){
+    if( dlrAtEnd(r2->pReader) ) return 0;  /* Both atEnd(). */
+    return 1;                              /* Only r1 atEnd(). */
+  }
+  if( dlrAtEnd(r2->pReader) ) return -1;   /* Only r2 atEnd(). */
+
+  if( dlrDocid(r1->pReader)pReader) ) return -1;
+  if( dlrDocid(r1->pReader)>dlrDocid(r2->pReader) ) return 1;
+
+  /* Descending on idx. */
+  return r2->idx-r1->idx;
+}
+
+/* Bubble p[0] to appropriate place in p[1..n-1].  Assumes that
+** p[1..n-1] is already sorted.
+*/
+/* TODO(shess) Is this frequent enough to warrant a binary search?
+** Before implementing that, instrument the code to check.  In most
+** current usage, I expect that p[0] will be less than p[1] a very
+** high proportion of the time.
+*/
+static void orderedDLReaderReorder(OrderedDLReader *p, int n){
+  while( n>1 && orderedDLReaderCmp(p, p+1)>0 ){
+    OrderedDLReader tmp = p[0];
+    p[0] = p[1];
+    p[1] = tmp;
+    n--;
+    p++;
+  }
+}
+
+/* Given an array of doclist readers, merge their doclist elements
+** into out in sorted order (by docid), dropping elements from older
+** readers when there is a duplicate docid.  pReaders is assumed to be
+** ordered by age, oldest first.
+*/
+/* TODO(shess) nReaders must be <= MERGE_COUNT.  This should probably
+** be fixed.
+*/
+static void docListMerge(DataBuffer *out,
+                         DLReader *pReaders, int nReaders){
+  OrderedDLReader readers[MERGE_COUNT];
+  DLWriter writer;
+  int i, n;
+  const char *pStart = 0;
+  int nStart = 0;
+  sqlite_int64 iFirstDocid = 0, iLastDocid = 0;
+
+  assert( nReaders>0 );
+  if( nReaders==1 ){
+    dataBufferAppend(out, dlrDocData(pReaders), dlrAllDataBytes(pReaders));
+    return;
+  }
+
+  assert( nReaders<=MERGE_COUNT );
+  n = 0;
+  for(i=0; i0 ){
+    orderedDLReaderReorder(readers+i, nReaders-i);
+  }
+
+  dlwInit(&writer, pReaders[0].iType, out);
+  while( !dlrAtEnd(readers[0].pReader) ){
+    sqlite_int64 iDocid = dlrDocid(readers[0].pReader);
+
+    /* If this is a continuation of the current buffer to copy, extend
+    ** that buffer.  memcpy() seems to be more efficient if it has a
+    ** lots of data to copy.
+    */
+    if( dlrDocData(readers[0].pReader)==pStart+nStart ){
+      nStart += dlrDocDataBytes(readers[0].pReader);
+    }else{
+      if( pStart!=0 ){
+        dlwAppend(&writer, pStart, nStart, iFirstDocid, iLastDocid);
+      }
+      pStart = dlrDocData(readers[0].pReader);
+      nStart = dlrDocDataBytes(readers[0].pReader);
+      iFirstDocid = iDocid;
+    }
+    iLastDocid = iDocid;
+    dlrStep(readers[0].pReader);
+
+    /* Drop all of the older elements with the same docid. */
+    for(i=1; i0 ){
+      orderedDLReaderReorder(readers+i, nReaders-i);
+    }
+  }
+
+  /* Copy over any remaining elements. */
+  if( nStart>0 ) dlwAppend(&writer, pStart, nStart, iFirstDocid, iLastDocid);
+  dlwDestroy(&writer);
+}
+
+/* Helper function for posListUnion().  Compares the current position
+** between left and right, returning as standard C idiom of <0 if
+** left0 if left>right, and 0 if left==right.  "End" always
+** compares greater.
+*/
+static int posListCmp(PLReader *pLeft, PLReader *pRight){
+  assert( pLeft->iType==pRight->iType );
+  if( pLeft->iType==DL_DOCIDS ) return 0;
+
+  if( plrAtEnd(pLeft) ) return plrAtEnd(pRight) ? 0 : 1;
+  if( plrAtEnd(pRight) ) return -1;
+
+  if( plrColumn(pLeft)plrColumn(pRight) ) return 1;
+
+  if( plrPosition(pLeft)plrPosition(pRight) ) return 1;
+  if( pLeft->iType==DL_POSITIONS ) return 0;
+
+  if( plrStartOffset(pLeft)plrStartOffset(pRight) ) return 1;
+
+  if( plrEndOffset(pLeft)plrEndOffset(pRight) ) return 1;
+
+  return 0;
+}
+
+/* Write the union of position lists in pLeft and pRight to pOut.
+** "Union" in this case meaning "All unique position tuples".  Should
+** work with any doclist type, though both inputs and the output
+** should be the same type.
+*/
+static void posListUnion(DLReader *pLeft, DLReader *pRight, DLWriter *pOut){
+  PLReader left, right;
+  PLWriter writer;
+
+  assert( dlrDocid(pLeft)==dlrDocid(pRight) );
+  assert( pLeft->iType==pRight->iType );
+  assert( pLeft->iType==pOut->iType );
+
+  plrInit(&left, pLeft);
+  plrInit(&right, pRight);
+  plwInit(&writer, pOut, dlrDocid(pLeft));
+
+  while( !plrAtEnd(&left) || !plrAtEnd(&right) ){
+    int c = posListCmp(&left, &right);
+    if( c<0 ){
+      plwCopy(&writer, &left);
+      plrStep(&left);
+    }else if( c>0 ){
+      plwCopy(&writer, &right);
+      plrStep(&right);
+    }else{
+      plwCopy(&writer, &left);
+      plrStep(&left);
+      plrStep(&right);
+    }
+  }
+
+  plwTerminate(&writer);
+  plwDestroy(&writer);
+  plrDestroy(&left);
+  plrDestroy(&right);
+}
+
+/* Write the union of doclists in pLeft and pRight to pOut.  For
+** docids in common between the inputs, the union of the position
+** lists is written.  Inputs and outputs are always type DL_DEFAULT.
+*/
+static void docListUnion(
+  const char *pLeft, int nLeft,
+  const char *pRight, int nRight,
+  DataBuffer *pOut      /* Write the combined doclist here */
+){
+  DLReader left, right;
+  DLWriter writer;
+
+  if( nLeft==0 ){
+    if( nRight!=0) dataBufferAppend(pOut, pRight, nRight);
+    return;
+  }
+  if( nRight==0 ){
+    dataBufferAppend(pOut, pLeft, nLeft);
+    return;
+  }
+
+  dlrInit(&left, DL_DEFAULT, pLeft, nLeft);
+  dlrInit(&right, DL_DEFAULT, pRight, nRight);
+  dlwInit(&writer, DL_DEFAULT, pOut);
+
+  while( !dlrAtEnd(&left) || !dlrAtEnd(&right) ){
+    if( dlrAtEnd(&right) ){
+      dlwCopy(&writer, &left);
+      dlrStep(&left);
+    }else if( dlrAtEnd(&left) ){
+      dlwCopy(&writer, &right);
+      dlrStep(&right);
+    }else if( dlrDocid(&left)dlrDocid(&right) ){
+      dlwCopy(&writer, &right);
+      dlrStep(&right);
+    }else{
+      posListUnion(&left, &right, &writer);
+      dlrStep(&left);
+      dlrStep(&right);
+    }
+  }
+
+  dlrDestroy(&left);
+  dlrDestroy(&right);
+  dlwDestroy(&writer);
+}
+
+/* 
+** This function is used as part of the implementation of phrase and
+** NEAR matching.
+**
+** pLeft and pRight are DLReaders positioned to the same docid in
+** lists of type DL_POSITION. This function writes an entry to the
+** DLWriter pOut for each position in pRight that is less than
+** (nNear+1) greater (but not equal to or smaller) than a position 
+** in pLeft. For example, if nNear is 0, and the positions contained
+** by pLeft and pRight are:
+**
+**    pLeft:  5 10 15 20
+**    pRight: 6  9 17 21
+**
+** then the docid is added to pOut. If pOut is of type DL_POSITIONS,
+** then a positionids "6" and "21" are also added to pOut.
+**
+** If boolean argument isSaveLeft is true, then positionids are copied
+** from pLeft instead of pRight. In the example above, the positions "5"
+** and "20" would be added instead of "6" and "21".
+*/
+static void posListPhraseMerge(
+  DLReader *pLeft, 
+  DLReader *pRight,
+  int nNear,
+  int isSaveLeft,
+  DLWriter *pOut
+){
+  PLReader left, right;
+  PLWriter writer;
+  int match = 0;
+
+  assert( dlrDocid(pLeft)==dlrDocid(pRight) );
+  assert( pOut->iType!=DL_POSITIONS_OFFSETS );
+
+  plrInit(&left, pLeft);
+  plrInit(&right, pRight);
+
+  while( !plrAtEnd(&left) && !plrAtEnd(&right) ){
+    if( plrColumn(&left)plrColumn(&right) ){
+      plrStep(&right);
+    }else if( plrPosition(&left)>=plrPosition(&right) ){
+      plrStep(&right);
+    }else{
+      if( (plrPosition(&right)-plrPosition(&left))<=(nNear+1) ){
+        if( !match ){
+          plwInit(&writer, pOut, dlrDocid(pLeft));
+          match = 1;
+        }
+        if( !isSaveLeft ){
+          plwAdd(&writer, plrColumn(&right), plrPosition(&right), 0, 0);
+        }else{
+          plwAdd(&writer, plrColumn(&left), plrPosition(&left), 0, 0);
+        }
+        plrStep(&right);
+      }else{
+        plrStep(&left);
+      }
+    }
+  }
+
+  if( match ){
+    plwTerminate(&writer);
+    plwDestroy(&writer);
+  }
+
+  plrDestroy(&left);
+  plrDestroy(&right);
+}
+
+/*
+** Compare the values pointed to by the PLReaders passed as arguments. 
+** Return -1 if the value pointed to by pLeft is considered less than
+** the value pointed to by pRight, +1 if it is considered greater
+** than it, or 0 if it is equal. i.e.
+**
+**     (*pLeft - *pRight)
+**
+** A PLReader that is in the EOF condition is considered greater than
+** any other. If neither argument is in EOF state, the return value of
+** plrColumn() is used. If the plrColumn() values are equal, the
+** comparison is on the basis of plrPosition().
+*/
+static int plrCompare(PLReader *pLeft, PLReader *pRight){
+  assert(!plrAtEnd(pLeft) || !plrAtEnd(pRight));
+
+  if( plrAtEnd(pRight) || plrAtEnd(pLeft) ){
+    return (plrAtEnd(pRight) ? -1 : 1);
+  }
+  if( plrColumn(pLeft)!=plrColumn(pRight) ){
+    return ((plrColumn(pLeft)0)
+** and write the results into pOut.
+**
+** A phrase intersection means that two documents only match
+** if pLeft.iPos+1==pRight.iPos.
+**
+** A NEAR intersection means that two documents only match if 
+** (abs(pLeft.iPos-pRight.iPos)    one AND (two OR three)
+ *    [one OR two three]     ==>    (one OR two) AND three
+ *
+ * A "-" before a term matches all entries that lack that term.
+ * The "-" must occur immediately before the term with in intervening
+ * space.  This is how the search engines do it.
+ *
+ * A NOT term cannot be the right-hand operand of an OR.  If this
+ * occurs in the query string, the NOT is ignored:
+ *
+ *    [one OR -two]          ==>    one OR two
+ *
+ */
+typedef struct Query {
+  fulltext_vtab *pFts;  /* The full text index */
+  int nTerms;           /* Number of terms in the query */
+  QueryTerm *pTerms;    /* Array of terms.  Space obtained from malloc() */
+  int nextIsOr;         /* Set the isOr flag on the next inserted term */
+  int nextIsNear;       /* Set the isOr flag on the next inserted term */
+  int nextColumn;       /* Next word parsed must be in this column */
+  int dfltColumn;       /* The default column */
+} Query;
+
+
+/*
+** An instance of the following structure keeps track of generated
+** matching-word offset information and snippets.
+*/
+typedef struct Snippet {
+  int nMatch;     /* Total number of matches */
+  int nAlloc;     /* Space allocated for aMatch[] */
+  struct snippetMatch { /* One entry for each matching term */
+    char snStatus;       /* Status flag for use while constructing snippets */
+    short int iCol;      /* The column that contains the match */
+    short int iTerm;     /* The index in Query.pTerms[] of the matching term */
+    int iToken;          /* The index of the matching document token */
+    short int nByte;     /* Number of bytes in the term */
+    int iStart;          /* The offset to the first character of the term */
+  } *aMatch;      /* Points to space obtained from malloc */
+  char *zOffset;  /* Text rendering of aMatch[] */
+  int nOffset;    /* strlen(zOffset) */
+  char *zSnippet; /* Snippet text */
+  int nSnippet;   /* strlen(zSnippet) */
+} Snippet;
+
+
+typedef enum QueryType {
+  QUERY_GENERIC,   /* table scan */
+  QUERY_DOCID,     /* lookup by docid */
+  QUERY_FULLTEXT   /* QUERY_FULLTEXT + [i] is a full-text search for column i*/
+} QueryType;
+
+typedef enum fulltext_statement {
+  CONTENT_INSERT_STMT,
+  CONTENT_SELECT_STMT,
+  CONTENT_UPDATE_STMT,
+  CONTENT_DELETE_STMT,
+  CONTENT_EXISTS_STMT,
+
+  BLOCK_INSERT_STMT,
+  BLOCK_SELECT_STMT,
+  BLOCK_DELETE_STMT,
+  BLOCK_DELETE_ALL_STMT,
+
+  SEGDIR_MAX_INDEX_STMT,
+  SEGDIR_SET_STMT,
+  SEGDIR_SELECT_LEVEL_STMT,
+  SEGDIR_SPAN_STMT,
+  SEGDIR_DELETE_STMT,
+  SEGDIR_SELECT_SEGMENT_STMT,
+  SEGDIR_SELECT_ALL_STMT,
+  SEGDIR_DELETE_ALL_STMT,
+  SEGDIR_COUNT_STMT,
+
+  MAX_STMT                     /* Always at end! */
+} fulltext_statement;
+
+/* These must exactly match the enum above. */
+/* TODO(shess): Is there some risk that a statement will be used in two
+** cursors at once, e.g.  if a query joins a virtual table to itself?
+** If so perhaps we should move some of these to the cursor object.
+*/
+static const char *const fulltext_zStatement[MAX_STMT] = {
+  /* CONTENT_INSERT */ NULL,  /* generated in contentInsertStatement() */
+  /* CONTENT_SELECT */ NULL,  /* generated in contentSelectStatement() */
+  /* CONTENT_UPDATE */ NULL,  /* generated in contentUpdateStatement() */
+  /* CONTENT_DELETE */ "delete from %_content where docid = ?",
+  /* CONTENT_EXISTS */ "select docid from %_content limit 1",
+
+  /* BLOCK_INSERT */
+  "insert into %_segments (blockid, block) values (null, ?)",
+  /* BLOCK_SELECT */ "select block from %_segments where blockid = ?",
+  /* BLOCK_DELETE */ "delete from %_segments where blockid between ? and ?",
+  /* BLOCK_DELETE_ALL */ "delete from %_segments",
+
+  /* SEGDIR_MAX_INDEX */ "select max(idx) from %_segdir where level = ?",
+  /* SEGDIR_SET */ "insert into %_segdir values (?, ?, ?, ?, ?, ?)",
+  /* SEGDIR_SELECT_LEVEL */
+  "select start_block, leaves_end_block, root from %_segdir "
+  " where level = ? order by idx",
+  /* SEGDIR_SPAN */
+  "select min(start_block), max(end_block) from %_segdir "
+  " where level = ? and start_block <> 0",
+  /* SEGDIR_DELETE */ "delete from %_segdir where level = ?",
+
+  /* NOTE(shess): The first three results of the following two
+  ** statements must match.
+  */
+  /* SEGDIR_SELECT_SEGMENT */
+  "select start_block, leaves_end_block, root from %_segdir "
+  " where level = ? and idx = ?",
+  /* SEGDIR_SELECT_ALL */
+  "select start_block, leaves_end_block, root from %_segdir "
+  " order by level desc, idx asc",
+  /* SEGDIR_DELETE_ALL */ "delete from %_segdir",
+  /* SEGDIR_COUNT */ "select count(*), ifnull(max(level),0) from %_segdir",
+};
+
+/*
+** A connection to a fulltext index is an instance of the following
+** structure.  The xCreate and xConnect methods create an instance
+** of this structure and xDestroy and xDisconnect free that instance.
+** All other methods receive a pointer to the structure as one of their
+** arguments.
+*/
+struct fulltext_vtab {
+  sqlite3_vtab base;               /* Base class used by SQLite core */
+  sqlite3 *db;                     /* The database connection */
+  const char *zDb;                 /* logical database name */
+  const char *zName;               /* virtual table name */
+  int nColumn;                     /* number of columns in virtual table */
+  char **azColumn;                 /* column names.  malloced */
+  char **azContentColumn;          /* column names in content table; malloced */
+  sqlite3_tokenizer *pTokenizer;   /* tokenizer for inserts and queries */
+
+  /* Precompiled statements which we keep as long as the table is
+  ** open.
+  */
+  sqlite3_stmt *pFulltextStatements[MAX_STMT];
+
+  /* Precompiled statements used for segment merges.  We run a
+  ** separate select across the leaf level of each tree being merged.
+  */
+  sqlite3_stmt *pLeafSelectStmts[MERGE_COUNT];
+  /* The statement used to prepare pLeafSelectStmts. */
+#define LEAF_SELECT \
+  "select block from %_segments where blockid between ? and ? order by blockid"
+
+  /* These buffer pending index updates during transactions.
+  ** nPendingData estimates the memory size of the pending data.  It
+  ** doesn't include the hash-bucket overhead, nor any malloc
+  ** overhead.  When nPendingData exceeds kPendingThreshold, the
+  ** buffer is flushed even before the transaction closes.
+  ** pendingTerms stores the data, and is only valid when nPendingData
+  ** is >=0 (nPendingData<0 means pendingTerms has not been
+  ** initialized).  iPrevDocid is the last docid written, used to make
+  ** certain we're inserting in sorted order.
+  */
+  int nPendingData;
+#define kPendingThreshold (1*1024*1024)
+  sqlite_int64 iPrevDocid;
+  fts3Hash pendingTerms;
+};
+
+/*
+** When the core wants to do a query, it create a cursor using a
+** call to xOpen.  This structure is an instance of a cursor.  It
+** is destroyed by xClose.
+*/
+typedef struct fulltext_cursor {
+  sqlite3_vtab_cursor base;        /* Base class used by SQLite core */
+  QueryType iCursorType;           /* Copy of sqlite3_index_info.idxNum */
+  sqlite3_stmt *pStmt;             /* Prepared statement in use by the cursor */
+  int eof;                         /* True if at End Of Results */
+  Query q;                         /* Parsed query string */
+  Snippet snippet;                 /* Cached snippet for the current row */
+  int iColumn;                     /* Column being searched */
+  DataBuffer result;               /* Doclist results from fulltextQuery */
+  DLReader reader;                 /* Result reader if result not empty */
+} fulltext_cursor;
+
+static struct fulltext_vtab *cursor_vtab(fulltext_cursor *c){
+  return (fulltext_vtab *) c->base.pVtab;
+}
+
+static const sqlite3_module fts3Module;   /* forward declaration */
+
+/* Return a dynamically generated statement of the form
+ *   insert into %_content (docid, ...) values (?, ...)
+ */
+static const char *contentInsertStatement(fulltext_vtab *v){
+  StringBuffer sb;
+  int i;
+
+  initStringBuffer(&sb);
+  append(&sb, "insert into %_content (docid, ");
+  appendList(&sb, v->nColumn, v->azContentColumn);
+  append(&sb, ") values (?");
+  for(i=0; inColumn; ++i)
+    append(&sb, ", ?");
+  append(&sb, ")");
+  return stringBufferData(&sb);
+}
+
+/* Return a dynamically generated statement of the form
+ *   select  from %_content where docid = ?
+ */
+static const char *contentSelectStatement(fulltext_vtab *v){
+  StringBuffer sb;
+  initStringBuffer(&sb);
+  append(&sb, "SELECT ");
+  appendList(&sb, v->nColumn, v->azContentColumn);
+  append(&sb, " FROM %_content WHERE docid = ?");
+  return stringBufferData(&sb);
+}
+
+/* Return a dynamically generated statement of the form
+ *   update %_content set [col_0] = ?, [col_1] = ?, ...
+ *                    where docid = ?
+ */
+static const char *contentUpdateStatement(fulltext_vtab *v){
+  StringBuffer sb;
+  int i;
+
+  initStringBuffer(&sb);
+  append(&sb, "update %_content set ");
+  for(i=0; inColumn; ++i) {
+    if( i>0 ){
+      append(&sb, ", ");
+    }
+    append(&sb, v->azContentColumn[i]);
+    append(&sb, " = ?");
+  }
+  append(&sb, " where docid = ?");
+  return stringBufferData(&sb);
+}
+
+/* Puts a freshly-prepared statement determined by iStmt in *ppStmt.
+** If the indicated statement has never been prepared, it is prepared
+** and cached, otherwise the cached version is reset.
+*/
+static int sql_get_statement(fulltext_vtab *v, fulltext_statement iStmt,
+                             sqlite3_stmt **ppStmt){
+  assert( iStmtpFulltextStatements[iStmt]==NULL ){
+    const char *zStmt;
+    int rc;
+    switch( iStmt ){
+      case CONTENT_INSERT_STMT:
+        zStmt = contentInsertStatement(v); break;
+      case CONTENT_SELECT_STMT:
+        zStmt = contentSelectStatement(v); break;
+      case CONTENT_UPDATE_STMT:
+        zStmt = contentUpdateStatement(v); break;
+      default:
+        zStmt = fulltext_zStatement[iStmt];
+    }
+    rc = sql_prepare(v->db, v->zDb, v->zName, &v->pFulltextStatements[iStmt],
+                         zStmt);
+    if( zStmt != fulltext_zStatement[iStmt]) sqlite3_free((void *) zStmt);
+    if( rc!=SQLITE_OK ) return rc;
+  } else {
+    int rc = sqlite3_reset(v->pFulltextStatements[iStmt]);
+    if( rc!=SQLITE_OK ) return rc;
+  }
+
+  *ppStmt = v->pFulltextStatements[iStmt];
+  return SQLITE_OK;
+}
+
+/* Like sqlite3_step(), but convert SQLITE_DONE to SQLITE_OK and
+** SQLITE_ROW to SQLITE_ERROR.  Useful for statements like UPDATE,
+** where we expect no results.
+*/
+static int sql_single_step(sqlite3_stmt *s){
+  int rc = sqlite3_step(s);
+  return (rc==SQLITE_DONE) ? SQLITE_OK : rc;
+}
+
+/* Like sql_get_statement(), but for special replicated LEAF_SELECT
+** statements.  idx -1 is a special case for an uncached version of
+** the statement (used in the optimize implementation).
+*/
+/* TODO(shess) Write version for generic statements and then share
+** that between the cached-statement functions.
+*/
+static int sql_get_leaf_statement(fulltext_vtab *v, int idx,
+                                  sqlite3_stmt **ppStmt){
+  assert( idx>=-1 && idxdb, v->zDb, v->zName, ppStmt, LEAF_SELECT);
+  }else if( v->pLeafSelectStmts[idx]==NULL ){
+    int rc = sql_prepare(v->db, v->zDb, v->zName, &v->pLeafSelectStmts[idx],
+                         LEAF_SELECT);
+    if( rc!=SQLITE_OK ) return rc;
+  }else{
+    int rc = sqlite3_reset(v->pLeafSelectStmts[idx]);
+    if( rc!=SQLITE_OK ) return rc;
+  }
 
+  *ppStmt = v->pLeafSelectStmts[idx];
+  return SQLITE_OK;
+}
 
-/************** Include fts3_hash.h in the middle of fts3.c ******************/
-/************** Begin file fts3_hash.h ***************************************/
-/*
-** 2001 September 22
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This is the header file for the generic hash-table implemenation
-** used in SQLite.  We've modified it slightly to serve as a standalone
-** hash table implementation for the full-text indexing module.
-**
+/* insert into %_content (docid, ...) values ([docid], [pValues])
+** If the docid contains SQL NULL, then a unique docid will be
+** generated.
 */
-#ifndef _FTS3_HASH_H_
-#define _FTS3_HASH_H_
+static int content_insert(fulltext_vtab *v, sqlite3_value *docid,
+                          sqlite3_value **pValues){
+  sqlite3_stmt *s;
+  int i;
+  int rc = sql_get_statement(v, CONTENT_INSERT_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-/* Forward declarations of structures. */
-typedef struct fts3Hash fts3Hash;
-typedef struct fts3HashElem fts3HashElem;
+  rc = sqlite3_bind_value(s, 1, docid);
+  if( rc!=SQLITE_OK ) return rc;
 
-/* A complete hash table is an instance of the following structure.
-** The internals of this structure are intended to be opaque -- client
-** code should not attempt to access or modify the fields of this structure
-** directly.  Change this structure only by using the routines below.
-** However, many of the "procedures" and "functions" for modifying and
-** accessing this structure are really macros, so we can't really make
-** this structure opaque.
-*/
-struct fts3Hash {
-  char keyClass;          /* HASH_INT, _POINTER, _STRING, _BINARY */
-  char copyKey;           /* True if copy of key made on insert */
-  int count;              /* Number of entries in this table */
-  fts3HashElem *first;    /* The first element of the array */
-  int htsize;             /* Number of buckets in the hash table */
-  struct _fts3ht {        /* the hash table */
-    int count;               /* Number of entries with this hash */
-    fts3HashElem *chain;     /* Pointer to first entry with this hash */
-  } *ht;
-};
+  for(i=0; inColumn; ++i){
+    rc = sqlite3_bind_value(s, 2+i, pValues[i]);
+    if( rc!=SQLITE_OK ) return rc;
+  }
 
-/* Each element in the hash table is an instance of the following 
-** structure.  All elements are stored on a single doubly-linked list.
-**
-** Again, this structure is intended to be opaque, but it can't really
-** be opaque because it is used by macros.
-*/
-struct fts3HashElem {
-  fts3HashElem *next, *prev; /* Next and previous elements in the table */
-  void *data;                /* Data associated with this element */
-  void *pKey; int nKey;      /* Key associated with this element */
-};
+  return sql_single_step(s);
+}
 
-/*
-** There are 2 different modes of operation for a hash table:
-**
-**   FTS3_HASH_STRING        pKey points to a string that is nKey bytes long
-**                           (including the null-terminator, if any).  Case
-**                           is respected in comparisons.
-**
-**   FTS3_HASH_BINARY        pKey points to binary data nKey bytes long. 
-**                           memcmp() is used to compare keys.
-**
-** A copy of the key is made if the copyKey parameter to fts3HashInit is 1.  
-*/
-#define FTS3_HASH_STRING    1
-#define FTS3_HASH_BINARY    2
+/* update %_content set col0 = pValues[0], col1 = pValues[1], ...
+ *                  where docid = [iDocid] */
+static int content_update(fulltext_vtab *v, sqlite3_value **pValues,
+                          sqlite_int64 iDocid){
+  sqlite3_stmt *s;
+  int i;
+  int rc = sql_get_statement(v, CONTENT_UPDATE_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-/*
-** Access routines.  To delete, insert a NULL pointer.
+  for(i=0; inColumn; ++i){
+    rc = sqlite3_bind_value(s, 1+i, pValues[i]);
+    if( rc!=SQLITE_OK ) return rc;
+  }
+
+  rc = sqlite3_bind_int64(s, 1+v->nColumn, iDocid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  return sql_single_step(s);
+}
+
+static void freeStringArray(int nString, const char **pString){
+  int i;
+
+  for (i=0 ; i < nString ; ++i) {
+    if( pString[i]!=NULL ) sqlite3_free((void *) pString[i]);
+  }
+  sqlite3_free((void *) pString);
+}
+
+/* select * from %_content where docid = [iDocid]
+ * The caller must delete the returned array and all strings in it.
+ * null fields will be NULL in the returned array.
+ *
+ * TODO: Perhaps we should return pointer/length strings here for consistency
+ * with other code which uses pointer/length. */
+static int content_select(fulltext_vtab *v, sqlite_int64 iDocid,
+                          const char ***pValues){
+  sqlite3_stmt *s;
+  const char **values;
+  int i;
+  int rc;
+
+  *pValues = NULL;
+
+  rc = sql_get_statement(v, CONTENT_SELECT_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int64(s, 1, iDocid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_step(s);
+  if( rc!=SQLITE_ROW ) return rc;
+
+  values = (const char **) sqlite3_malloc(v->nColumn * sizeof(const char *));
+  for(i=0; inColumn; ++i){
+    if( sqlite3_column_type(s, i)==SQLITE_NULL ){
+      values[i] = NULL;
+    }else{
+      values[i] = string_dup((char*)sqlite3_column_text(s, i));
+    }
+  }
+
+  /* We expect only one row.  We must execute another sqlite3_step()
+   * to complete the iteration; otherwise the table will remain locked. */
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_DONE ){
+    *pValues = values;
+    return SQLITE_OK;
+  }
+
+  freeStringArray(v->nColumn, values);
+  return rc;
+}
+
+/* delete from %_content where docid = [iDocid ] */
+static int content_delete(fulltext_vtab *v, sqlite_int64 iDocid){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, CONTENT_DELETE_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int64(s, 1, iDocid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  return sql_single_step(s);
+}
+
+/* Returns SQLITE_ROW if any rows exist in %_content, SQLITE_DONE if
+** no rows exist, and any error in case of failure.
 */
-SQLITE_PRIVATE void sqlite3Fts3HashInit(fts3Hash*, int keytype, int copyKey);
-SQLITE_PRIVATE void *sqlite3Fts3HashInsert(fts3Hash*, const void *pKey, int nKey, void *pData);
-SQLITE_PRIVATE void *sqlite3Fts3HashFind(const fts3Hash*, const void *pKey, int nKey);
-SQLITE_PRIVATE void sqlite3Fts3HashClear(fts3Hash*);
+static int content_exists(fulltext_vtab *v){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, CONTENT_EXISTS_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-/*
-** Shorthand for the functions above
+  rc = sqlite3_step(s);
+  if( rc!=SQLITE_ROW ) return rc;
+
+  /* We expect only one row.  We must execute another sqlite3_step()
+   * to complete the iteration; otherwise the table will remain locked. */
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_DONE ) return SQLITE_ROW;
+  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
+  return rc;
+}
+
+/* insert into %_segments values ([pData])
+**   returns assigned blockid in *piBlockid
 */
-#define fts3HashInit   sqlite3Fts3HashInit
-#define fts3HashInsert sqlite3Fts3HashInsert
-#define fts3HashFind   sqlite3Fts3HashFind
-#define fts3HashClear  sqlite3Fts3HashClear
+static int block_insert(fulltext_vtab *v, const char *pData, int nData,
+                        sqlite_int64 *piBlockid){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, BLOCK_INSERT_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-/*
-** Macros for looping over all elements of a hash table.  The idiom is
-** like this:
+  rc = sqlite3_bind_blob(s, 1, pData, nData, SQLITE_STATIC);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
+  if( rc!=SQLITE_DONE ) return rc;
+
+  /* blockid column is an alias for rowid. */
+  *piBlockid = sqlite3_last_insert_rowid(v->db);
+  return SQLITE_OK;
+}
+
+/* delete from %_segments
+**   where blockid between [iStartBlockid] and [iEndBlockid]
 **
-**   fts3Hash h;
-**   fts3HashElem *p;
-**   ...
-**   for(p=fts3HashFirst(&h); p; p=fts3HashNext(p)){
-**     SomeStructure *pData = fts3HashData(p);
-**     // do something with pData
-**   }
+** Deletes the range of blocks, inclusive, used to delete the blocks
+** which form a segment.
 */
-#define fts3HashFirst(H)  ((H)->first)
-#define fts3HashNext(E)   ((E)->next)
-#define fts3HashData(E)   ((E)->data)
-#define fts3HashKey(E)    ((E)->pKey)
-#define fts3HashKeysize(E) ((E)->nKey)
+static int block_delete(fulltext_vtab *v,
+                        sqlite_int64 iStartBlockid, sqlite_int64 iEndBlockid){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, BLOCK_DELETE_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-/*
-** Number of entries in a hash table
-*/
-#define fts3HashCount(H)  ((H)->count)
+  rc = sqlite3_bind_int64(s, 1, iStartBlockid);
+  if( rc!=SQLITE_OK ) return rc;
 
-#endif /* _FTS3_HASH_H_ */
+  rc = sqlite3_bind_int64(s, 2, iEndBlockid);
+  if( rc!=SQLITE_OK ) return rc;
 
-/************** End of fts3_hash.h *******************************************/
-/************** Continuing where we left off in fts3.c ***********************/
-/************** Include fts3_tokenizer.h in the middle of fts3.c *************/
-/************** Begin file fts3_tokenizer.h **********************************/
-/*
-** 2006 July 10
-**
-** The author disclaims copyright to this source code.
-**
-*************************************************************************
-** Defines the interface to tokenizers used by fulltext-search.  There
-** are three basic components:
-**
-** sqlite3_tokenizer_module is a singleton defining the tokenizer
-** interface functions.  This is essentially the class structure for
-** tokenizers.
-**
-** sqlite3_tokenizer is used to define a particular tokenizer, perhaps
-** including customization information defined at creation time.
-**
-** sqlite3_tokenizer_cursor is generated by a tokenizer to generate
-** tokens from a particular input.
+  return sql_single_step(s);
+}
+
+/* Returns SQLITE_ROW with *pidx set to the maximum segment idx found
+** at iLevel.  Returns SQLITE_DONE if there are no segments at
+** iLevel.  Otherwise returns an error.
 */
-#ifndef _FTS3_TOKENIZER_H_
-#define _FTS3_TOKENIZER_H_
+static int segdir_max_index(fulltext_vtab *v, int iLevel, int *pidx){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, SEGDIR_MAX_INDEX_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-/* TODO(shess) Only used for SQLITE_OK and SQLITE_DONE at this time.
-** If tokenizers are to be allowed to call sqlite3_*() functions, then
-** we will need a way to register the API consistently.
+  rc = sqlite3_bind_int(s, 1, iLevel);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_step(s);
+  /* Should always get at least one row due to how max() works. */
+  if( rc==SQLITE_DONE ) return SQLITE_DONE;
+  if( rc!=SQLITE_ROW ) return rc;
+
+  /* NULL means that there were no inputs to max(). */
+  if( SQLITE_NULL==sqlite3_column_type(s, 0) ){
+    rc = sqlite3_step(s);
+    if( rc==SQLITE_ROW ) return SQLITE_ERROR;
+    return rc;
+  }
+
+  *pidx = sqlite3_column_int(s, 0);
+
+  /* We expect only one row.  We must execute another sqlite3_step()
+   * to complete the iteration; otherwise the table will remain locked. */
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
+  if( rc!=SQLITE_DONE ) return rc;
+  return SQLITE_ROW;
+}
+
+/* insert into %_segdir values (
+**   [iLevel], [idx],
+**   [iStartBlockid], [iLeavesEndBlockid], [iEndBlockid],
+**   [pRootData]
+** )
 */
+static int segdir_set(fulltext_vtab *v, int iLevel, int idx,
+                      sqlite_int64 iStartBlockid,
+                      sqlite_int64 iLeavesEndBlockid,
+                      sqlite_int64 iEndBlockid,
+                      const char *pRootData, int nRootData){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, SEGDIR_SET_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-/*
-** Structures used by the tokenizer interface. When a new tokenizer
-** implementation is registered, the caller provides a pointer to
-** an sqlite3_tokenizer_module containing pointers to the callback
-** functions that make up an implementation.
-**
-** When an fts3 table is created, it passes any arguments passed to
-** the tokenizer clause of the CREATE VIRTUAL TABLE statement to the
-** sqlite3_tokenizer_module.xCreate() function of the requested tokenizer
-** implementation. The xCreate() function in turn returns an 
-** sqlite3_tokenizer structure representing the specific tokenizer to
-** be used for the fts3 table (customized by the tokenizer clause arguments).
-**
-** To tokenize an input buffer, the sqlite3_tokenizer_module.xOpen()
-** method is called. It returns an sqlite3_tokenizer_cursor object
-** that may be used to tokenize a specific input buffer based on
-** the tokenization rules supplied by a specific sqlite3_tokenizer
-** object.
+  rc = sqlite3_bind_int(s, 1, iLevel);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int(s, 2, idx);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int64(s, 3, iStartBlockid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int64(s, 4, iLeavesEndBlockid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int64(s, 5, iEndBlockid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_blob(s, 6, pRootData, nRootData, SQLITE_STATIC);
+  if( rc!=SQLITE_OK ) return rc;
+
+  return sql_single_step(s);
+}
+
+/* Queries %_segdir for the block span of the segments in level
+** iLevel.  Returns SQLITE_DONE if there are no blocks for iLevel,
+** SQLITE_ROW if there are blocks, else an error.
 */
-typedef struct sqlite3_tokenizer_module sqlite3_tokenizer_module;
-typedef struct sqlite3_tokenizer sqlite3_tokenizer;
-typedef struct sqlite3_tokenizer_cursor sqlite3_tokenizer_cursor;
+static int segdir_span(fulltext_vtab *v, int iLevel,
+                       sqlite_int64 *piStartBlockid,
+                       sqlite_int64 *piEndBlockid){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, SEGDIR_SPAN_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-struct sqlite3_tokenizer_module {
+  rc = sqlite3_bind_int(s, 1, iLevel);
+  if( rc!=SQLITE_OK ) return rc;
 
-  /*
-  ** Structure version. Should always be set to 0.
-  */
-  int iVersion;
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_DONE ) return SQLITE_DONE;  /* Should never happen */
+  if( rc!=SQLITE_ROW ) return rc;
 
-  /*
-  ** Create a new tokenizer. The values in the argv[] array are the
-  ** arguments passed to the "tokenizer" clause of the CREATE VIRTUAL
-  ** TABLE statement that created the fts3 table. For example, if
-  ** the following SQL is executed:
-  **
-  **   CREATE .. USING fts3( ... , tokenizer  arg1 arg2)
-  **
-  ** then argc is set to 2, and the argv[] array contains pointers
-  ** to the strings "arg1" and "arg2".
-  **
-  ** This method should return either SQLITE_OK (0), or an SQLite error 
-  ** code. If SQLITE_OK is returned, then *ppTokenizer should be set
-  ** to point at the newly created tokenizer structure. The generic
-  ** sqlite3_tokenizer.pModule variable should not be initialised by
-  ** this callback. The caller will do so.
-  */
-  int (*xCreate)(
-    int argc,                           /* Size of argv array */
-    const char *const*argv,             /* Tokenizer argument strings */
-    sqlite3_tokenizer **ppTokenizer     /* OUT: Created tokenizer */
-  );
+  /* This happens if all segments at this level are entirely inline. */
+  if( SQLITE_NULL==sqlite3_column_type(s, 0) ){
+    /* We expect only one row.  We must execute another sqlite3_step()
+     * to complete the iteration; otherwise the table will remain locked. */
+    int rc2 = sqlite3_step(s);
+    if( rc2==SQLITE_ROW ) return SQLITE_ERROR;
+    return rc2;
+  }
 
-  /*
-  ** Destroy an existing tokenizer. The fts3 module calls this method
-  ** exactly once for each successful call to xCreate().
-  */
-  int (*xDestroy)(sqlite3_tokenizer *pTokenizer);
+  *piStartBlockid = sqlite3_column_int64(s, 0);
+  *piEndBlockid = sqlite3_column_int64(s, 1);
 
-  /*
-  ** Create a tokenizer cursor to tokenize an input buffer. The caller
-  ** is responsible for ensuring that the input buffer remains valid
-  ** until the cursor is closed (using the xClose() method). 
-  */
-  int (*xOpen)(
-    sqlite3_tokenizer *pTokenizer,       /* Tokenizer object */
-    const char *pInput, int nBytes,      /* Input buffer */
-    sqlite3_tokenizer_cursor **ppCursor  /* OUT: Created tokenizer cursor */
-  );
+  /* We expect only one row.  We must execute another sqlite3_step()
+   * to complete the iteration; otherwise the table will remain locked. */
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
+  if( rc!=SQLITE_DONE ) return rc;
+  return SQLITE_ROW;
+}
 
-  /*
-  ** Destroy an existing tokenizer cursor. The fts3 module calls this 
-  ** method exactly once for each successful call to xOpen().
-  */
-  int (*xClose)(sqlite3_tokenizer_cursor *pCursor);
+/* Delete the segment blocks and segment directory records for all
+** segments at iLevel.
+*/
+static int segdir_delete(fulltext_vtab *v, int iLevel){
+  sqlite3_stmt *s;
+  sqlite_int64 iStartBlockid, iEndBlockid;
+  int rc = segdir_span(v, iLevel, &iStartBlockid, &iEndBlockid);
+  if( rc!=SQLITE_ROW && rc!=SQLITE_DONE ) return rc;
 
-  /*
-  ** Retrieve the next token from the tokenizer cursor pCursor. This
-  ** method should either return SQLITE_OK and set the values of the
-  ** "OUT" variables identified below, or SQLITE_DONE to indicate that
-  ** the end of the buffer has been reached, or an SQLite error code.
-  **
-  ** *ppToken should be set to point at a buffer containing the 
-  ** normalized version of the token (i.e. after any case-folding and/or
-  ** stemming has been performed). *pnBytes should be set to the length
-  ** of this buffer in bytes. The input text that generated the token is
-  ** identified by the byte offsets returned in *piStartOffset and
-  ** *piEndOffset.
-  **
-  ** The buffer *ppToken is set to point at is managed by the tokenizer
-  ** implementation. It is only required to be valid until the next call
-  ** to xNext() or xClose(). 
-  */
-  /* TODO(shess) current implementation requires pInput to be
-  ** nul-terminated.  This should either be fixed, or pInput/nBytes
-  ** should be converted to zInput.
-  */
-  int (*xNext)(
-    sqlite3_tokenizer_cursor *pCursor,   /* Tokenizer cursor */
-    const char **ppToken, int *pnBytes,  /* OUT: Normalized text for token */
-    int *piStartOffset,  /* OUT: Byte offset of token in input buffer */
-    int *piEndOffset,    /* OUT: Byte offset of end of token in input buffer */
-    int *piPosition      /* OUT: Number of tokens returned before this one */
-  );
-};
+  if( rc==SQLITE_ROW ){
+    rc = block_delete(v, iStartBlockid, iEndBlockid);
+    if( rc!=SQLITE_OK ) return rc;
+  }
+
+  /* Delete the segment directory itself. */
+  rc = sql_get_statement(v, SEGDIR_DELETE_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = sqlite3_bind_int64(s, 1, iLevel);
+  if( rc!=SQLITE_OK ) return rc;
 
-struct sqlite3_tokenizer {
-  const sqlite3_tokenizer_module *pModule;  /* The module for this tokenizer */
-  /* Tokenizer implementations will typically add additional fields */
-};
+  return sql_single_step(s);
+}
 
-struct sqlite3_tokenizer_cursor {
-  sqlite3_tokenizer *pTokenizer;       /* Tokenizer for this cursor. */
-  /* Tokenizer implementations will typically add additional fields */
-};
+/* Delete entire fts index, SQLITE_OK on success, relevant error on
+** failure.
+*/
+static int segdir_delete_all(fulltext_vtab *v){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, SEGDIR_DELETE_ALL_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-#endif /* _FTS3_TOKENIZER_H_ */
+  rc = sql_single_step(s);
+  if( rc!=SQLITE_OK ) return rc;
 
-/************** End of fts3_tokenizer.h **************************************/
-/************** Continuing where we left off in fts3.c ***********************/
-#ifndef SQLITE_CORE 
-  SQLITE_EXTENSION_INIT1
-#endif
+  rc = sql_get_statement(v, BLOCK_DELETE_ALL_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
+  return sql_single_step(s);
+}
 
-/* TODO(shess) MAN, this thing needs some refactoring.  At minimum, it
-** would be nice to order the file better, perhaps something along the
-** lines of:
-**
-**  - utility functions
-**  - table setup functions
-**  - table update functions
-**  - table query functions
-**
-** Put the query functions last because they're likely to reference
-** typedefs or functions from the table update section.
+/* Returns SQLITE_OK with *pnSegments set to the number of entries in
+** %_segdir and *piMaxLevel set to the highest level which has a
+** segment.  Otherwise returns the SQLite error which caused failure.
 */
+static int segdir_count(fulltext_vtab *v, int *pnSegments, int *piMaxLevel){
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, SEGDIR_COUNT_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-#if 0
-# define FTSTRACE(A)  printf A; fflush(stdout)
-#else
-# define FTSTRACE(A)
-#endif
+  rc = sqlite3_step(s);
+  /* TODO(shess): This case should not be possible?  Should stronger
+  ** measures be taken if it happens?
+  */
+  if( rc==SQLITE_DONE ){
+    *pnSegments = 0;
+    *piMaxLevel = 0;
+    return SQLITE_OK;
+  }
+  if( rc!=SQLITE_ROW ) return rc;
 
-/*
-** Default span for NEAR operators.
-*/
-#define SQLITE_FTS3_DEFAULT_NEAR_PARAM 10
+  *pnSegments = sqlite3_column_int(s, 0);
+  *piMaxLevel = sqlite3_column_int(s, 1);
 
-/* It is not safe to call isspace(), tolower(), or isalnum() on
-** hi-bit-set characters.  This is the same solution used in the
-** tokenizer.
-*/
-/* TODO(shess) The snippet-generation code should be using the
-** tokenizer-generated tokens rather than doing its own local
-** tokenization.
-*/
-/* TODO(shess) Is __isascii() a portable version of (c&0x80)==0? */
-static int safe_isspace(char c){
-  return (c&0x80)==0 ? isspace(c) : 0;
-}
-static int safe_tolower(char c){
-  return (c&0x80)==0 ? tolower(c) : c;
-}
-static int safe_isalnum(char c){
-  return (c&0x80)==0 ? isalnum(c) : 0;
+  /* We expect only one row.  We must execute another sqlite3_step()
+   * to complete the iteration; otherwise the table will remain locked. */
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_DONE ) return SQLITE_OK;
+  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
+  return rc;
 }
 
-typedef enum DocListType {
-  DL_DOCIDS,              /* docids only */
-  DL_POSITIONS,           /* docids + positions */
-  DL_POSITIONS_OFFSETS    /* docids + positions + offsets */
-} DocListType;
+/* TODO(shess) clearPendingTerms() is far down the file because
+** writeZeroSegment() is far down the file because LeafWriter is far
+** down the file.  Consider refactoring the code to move the non-vtab
+** code above the vtab code so that we don't need this forward
+** reference.
+*/
+static int clearPendingTerms(fulltext_vtab *v);
 
 /*
-** By default, only positions and not offsets are stored in the doclists.
-** To change this so that offsets are stored too, compile with
-**
-**          -DDL_DEFAULT=DL_POSITIONS_OFFSETS
-**
-** If DL_DEFAULT is set to DL_DOCIDS, your table can only be inserted
-** into (no deletes or updates).
+** Free the memory used to contain a fulltext_vtab structure.
 */
-#ifndef DL_DEFAULT
-# define DL_DEFAULT DL_POSITIONS
-#endif
+static void fulltext_vtab_destroy(fulltext_vtab *v){
+  int iStmt, i;
 
-enum {
-  POS_END = 0,        /* end of this position list */
-  POS_COLUMN,         /* followed by new column number */
-  POS_BASE
-};
+  FTSTRACE(("FTS3 Destroy %p\n", v));
+  for( iStmt=0; iStmtpFulltextStatements[iStmt]!=NULL ){
+      sqlite3_finalize(v->pFulltextStatements[iStmt]);
+      v->pFulltextStatements[iStmt] = NULL;
+    }
+  }
 
-/* MERGE_COUNT controls how often we merge segments (see comment at
-** top of file).
-*/
-#define MERGE_COUNT 16
+  for( i=0; ipLeafSelectStmts[i]!=NULL ){
+      sqlite3_finalize(v->pLeafSelectStmts[i]);
+      v->pLeafSelectStmts[i] = NULL;
+    }
+  }
 
-/* utility functions */
+  if( v->pTokenizer!=NULL ){
+    v->pTokenizer->pModule->xDestroy(v->pTokenizer);
+    v->pTokenizer = NULL;
+  }
 
-/* CLEAR() and SCRAMBLE() abstract memset() on a pointer to a single
-** record to prevent errors of the form:
-**
-** my_function(SomeType *b){
-**   memset(b, '\0', sizeof(b));  // sizeof(b)!=sizeof(*b)
-** }
-*/
-/* TODO(shess) Obvious candidates for a header file. */
-#define CLEAR(b) memset(b, '\0', sizeof(*(b)))
+  clearPendingTerms(v);
 
-#ifndef NDEBUG
-#  define SCRAMBLE(b) memset(b, 0x55, sizeof(*(b)))
-#else
-#  define SCRAMBLE(b)
-#endif
+  sqlite3_free(v->azColumn);
+  for(i = 0; i < v->nColumn; ++i) {
+    sqlite3_free(v->azContentColumn[i]);
+  }
+  sqlite3_free(v->azContentColumn);
+  sqlite3_free(v);
+}
 
-/* We may need up to VARINT_MAX bytes to store an encoded 64-bit integer. */
-#define VARINT_MAX 10
+/*
+** Token types for parsing the arguments to xConnect or xCreate.
+*/
+#define TOKEN_EOF         0    /* End of file */
+#define TOKEN_SPACE       1    /* Any kind of whitespace */
+#define TOKEN_ID          2    /* An identifier */
+#define TOKEN_STRING      3    /* A string literal */
+#define TOKEN_PUNCT       4    /* A single punctuation character */
 
-/* Write a 64-bit variable-length integer to memory starting at p[0].
- * The length of data written will be between 1 and VARINT_MAX bytes.
- * The number of bytes written is returned. */
-static int fts3PutVarint(char *p, sqlite_int64 v){
-  unsigned char *q = (unsigned char *) p;
-  sqlite_uint64 vu = v;
-  do{
-    *q++ = (unsigned char) ((vu & 0x7f) | 0x80);
-    vu >>= 7;
-  }while( vu!=0 );
-  q[-1] &= 0x7f;  /* turn off high bit in final byte */
-  assert( q - (unsigned char *)p <= VARINT_MAX );
-  return (int) (q - (unsigned char *)p);
-}
+/*
+** If X is a character that can be used in an identifier then
+** ftsIdChar(X) will be true.  Otherwise it is false.
+**
+** For ASCII, any character with the high-order bit set is
+** allowed in an identifier.  For 7-bit characters, 
+** isFtsIdChar[X] must be 1.
+**
+** Ticket #1066.  the SQL standard does not allow '$' in the
+** middle of identfiers.  But many SQL implementations do. 
+** SQLite will allow '$' in identifiers for compatibility.
+** But the feature is undocumented.
+*/
+static const char isFtsIdChar[] = {
+/* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */
+    0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /* 2x */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,  /* 3x */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 4x */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1,  /* 5x */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 6x */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,  /* 7x */
+};
+#define ftsIdChar(C)  (((c=C)&0x80)!=0 || (c>0x1f && isFtsIdChar[c-0x20]))
 
-/* Read a 64-bit variable-length integer from memory starting at p[0].
- * Return the number of bytes read, or 0 on error.
- * The value is stored in *v. */
-static int fts3GetVarint(const char *p, sqlite_int64 *v){
-  const unsigned char *q = (const unsigned char *) p;
-  sqlite_uint64 x = 0, y = 1;
-  while( (*q & 0x80) == 0x80 ){
-    x += y * (*q++ & 0x7f);
-    y <<= 7;
-    if( q - (unsigned char *)p >= VARINT_MAX ){  /* bad data */
-      assert( 0 );
+
+/*
+** Return the length of the token that begins at z[0]. 
+** Store the token type in *tokenType before returning.
+*/
+static int ftsGetToken(const char *z, int *tokenType){
+  int i, c;
+  switch( *z ){
+    case 0: {
+      *tokenType = TOKEN_EOF;
       return 0;
     }
+    case ' ': case '\t': case '\n': case '\f': case '\r': {
+      for(i=1; safe_isspace(z[i]); i++){}
+      *tokenType = TOKEN_SPACE;
+      return i;
+    }
+    case '`':
+    case '\'':
+    case '"': {
+      int delim = z[0];
+      for(i=1; (c=z[i])!=0; i++){
+        if( c==delim ){
+          if( z[i+1]==delim ){
+            i++;
+          }else{
+            break;
+          }
+        }
+      }
+      *tokenType = TOKEN_STRING;
+      return i + (c!=0);
+    }
+    case '[': {
+      for(i=1, c=z[0]; c!=']' && (c=z[i])!=0; i++){}
+      *tokenType = TOKEN_ID;
+      return i;
+    }
+    default: {
+      if( !ftsIdChar(*z) ){
+        break;
+      }
+      for(i=1; ftsIdChar(z[i]); i++){}
+      *tokenType = TOKEN_ID;
+      return i;
+    }
   }
-  x += y * (*q++);
-  *v = (sqlite_int64) x;
-  return (int) (q - (unsigned char *)p);
+  *tokenType = TOKEN_PUNCT;
+  return 1;
 }
 
-static int fts3GetVarint32(const char *p, int *pi){
- sqlite_int64 i;
- int ret = fts3GetVarint(p, &i);
- *pi = (int) i;
- assert( *pi==i );
- return ret;
-}
+/*
+** A token extracted from a string is an instance of the following
+** structure.
+*/
+typedef struct FtsToken {
+  const char *z;       /* Pointer to token text.  Not '\000' terminated */
+  short int n;         /* Length of the token text in bytes. */
+} FtsToken;
 
-/*******************************************************************/
-/* DataBuffer is used to collect data into a buffer in piecemeal
-** fashion.  It implements the usual distinction between amount of
-** data currently stored (nData) and buffer capacity (nCapacity).
+/*
+** Given a input string (which is really one of the argv[] parameters
+** passed into xConnect or xCreate) split the string up into tokens.
+** Return an array of pointers to '\000' terminated strings, one string
+** for each non-whitespace token.
 **
-** dataBufferInit - create a buffer with given initial capacity.
-** dataBufferReset - forget buffer's data, retaining capacity.
-** dataBufferDestroy - free buffer's data.
-** dataBufferSwap - swap contents of two buffers.
-** dataBufferExpand - expand capacity without adding data.
-** dataBufferAppend - append data.
-** dataBufferAppend2 - append two pieces of data at once.
-** dataBufferReplace - replace buffer's data.
+** The returned array is terminated by a single NULL pointer.
+**
+** Space to hold the returned array is obtained from a single
+** malloc and should be freed by passing the return value to free().
+** The individual strings within the token list are all a part of
+** the single memory allocation and will all be freed at once.
 */
-typedef struct DataBuffer {
-  char *pData;          /* Pointer to malloc'ed buffer. */
-  int nCapacity;        /* Size of pData buffer. */
-  int nData;            /* End of data loaded into pData. */
-} DataBuffer;
-
-static void dataBufferInit(DataBuffer *pBuffer, int nCapacity){
-  assert( nCapacity>=0 );
-  pBuffer->nData = 0;
-  pBuffer->nCapacity = nCapacity;
-  pBuffer->pData = nCapacity==0 ? NULL : sqlite3_malloc(nCapacity);
-}
-static void dataBufferReset(DataBuffer *pBuffer){
-  pBuffer->nData = 0;
-}
-static void dataBufferDestroy(DataBuffer *pBuffer){
-  if( pBuffer->pData!=NULL ) sqlite3_free(pBuffer->pData);
-  SCRAMBLE(pBuffer);
-}
-static void dataBufferSwap(DataBuffer *pBuffer1, DataBuffer *pBuffer2){
-  DataBuffer tmp = *pBuffer1;
-  *pBuffer1 = *pBuffer2;
-  *pBuffer2 = tmp;
-}
-static void dataBufferExpand(DataBuffer *pBuffer, int nAddCapacity){
-  assert( nAddCapacity>0 );
-  /* TODO(shess) Consider expanding more aggressively.  Note that the
-  ** underlying malloc implementation may take care of such things for
-  ** us already.
-  */
-  if( pBuffer->nData+nAddCapacity>pBuffer->nCapacity ){
-    pBuffer->nCapacity = pBuffer->nData+nAddCapacity;
-    pBuffer->pData = sqlite3_realloc(pBuffer->pData, pBuffer->nCapacity);
+static char **tokenizeString(const char *z, int *pnToken){
+  int nToken = 0;
+  FtsToken *aToken = sqlite3_malloc( strlen(z) * sizeof(aToken[0]) );
+  int n = 1;
+  int e, i;
+  int totalSize = 0;
+  char **azToken;
+  char *zCopy;
+  while( n>0 ){
+    n = ftsGetToken(z, &e);
+    if( e!=TOKEN_SPACE ){
+      aToken[nToken].z = z;
+      aToken[nToken].n = n;
+      nToken++;
+      totalSize += n+1;
+    }
+    z += n;
   }
-}
-static void dataBufferAppend(DataBuffer *pBuffer,
-                             const char *pSource, int nSource){
-  assert( nSource>0 && pSource!=NULL );
-  dataBufferExpand(pBuffer, nSource);
-  memcpy(pBuffer->pData+pBuffer->nData, pSource, nSource);
-  pBuffer->nData += nSource;
-}
-static void dataBufferAppend2(DataBuffer *pBuffer,
-                              const char *pSource1, int nSource1,
-                              const char *pSource2, int nSource2){
-  assert( nSource1>0 && pSource1!=NULL );
-  assert( nSource2>0 && pSource2!=NULL );
-  dataBufferExpand(pBuffer, nSource1+nSource2);
-  memcpy(pBuffer->pData+pBuffer->nData, pSource1, nSource1);
-  memcpy(pBuffer->pData+pBuffer->nData+nSource1, pSource2, nSource2);
-  pBuffer->nData += nSource1+nSource2;
-}
-static void dataBufferReplace(DataBuffer *pBuffer,
-                              const char *pSource, int nSource){
-  dataBufferReset(pBuffer);
-  dataBufferAppend(pBuffer, pSource, nSource);
-}
-
-/* StringBuffer is a null-terminated version of DataBuffer. */
-typedef struct StringBuffer {
-  DataBuffer b;            /* Includes null terminator. */
-} StringBuffer;
-
-static void initStringBuffer(StringBuffer *sb){
-  dataBufferInit(&sb->b, 100);
-  dataBufferReplace(&sb->b, "", 1);
-}
-static int stringBufferLength(StringBuffer *sb){
-  return sb->b.nData-1;
-}
-static char *stringBufferData(StringBuffer *sb){
-  return sb->b.pData;
-}
-static void stringBufferDestroy(StringBuffer *sb){
-  dataBufferDestroy(&sb->b);
+  azToken = (char**)sqlite3_malloc( nToken*sizeof(char*) + totalSize );
+  zCopy = (char*)&azToken[nToken];
+  nToken--;
+  for(i=0; ib.nData>0 );
-  if( nFrom>0 ){
-    sb->b.nData--;
-    dataBufferAppend2(&sb->b, zFrom, nFrom, "", 1);
+/*
+** Convert an SQL-style quoted string into a normal string by removing
+** the quote characters.  The conversion is done in-place.  If the
+** input does not begin with a quote character, then this routine
+** is a no-op.
+**
+** Examples:
+**
+**     "abc"   becomes   abc
+**     'xyz'   becomes   xyz
+**     [pqr]   becomes   pqr
+**     `mno`   becomes   mno
+*/
+static void dequoteString(char *z){
+  int quote;
+  int i, j;
+  if( z==0 ) return;
+  quote = z[0];
+  switch( quote ){
+    case '\'':  break;
+    case '"':   break;
+    case '`':   break;                /* For MySQL compatibility */
+    case '[':   quote = ']';  break;  /* For MS SqlServer compatibility */
+    default:    return;
+  }
+  for(i=1, j=0; z[i]; i++){
+    if( z[i]==quote ){
+      if( z[i+1]==quote ){
+        z[j++] = quote;
+        i++;
+      }else{
+        z[j++] = 0;
+        break;
+      }
+    }else{
+      z[j++] = z[i];
+    }
   }
-}
-static void append(StringBuffer *sb, const char *zFrom){
-  nappend(sb, zFrom, strlen(zFrom));
 }
 
-/* Append a list of strings separated by commas. */
-static void appendList(StringBuffer *sb, int nString, char **azString){
-  int i;
-  for(i=0; i0 ) append(sb, ", ");
-    append(sb, azString[i]);
+/*
+** The input azIn is a NULL-terminated list of tokens.  Remove the first
+** token and all punctuation tokens.  Remove the quotes from
+** around string literal tokens.
+**
+** Example:
+**
+**     input:      tokenize chinese ( 'simplifed' , 'mixed' )
+**     output:     chinese simplifed mixed
+**
+** Another example:
+**
+**     input:      delimiters ( '[' , ']' , '...' )
+**     output:     [ ] ...
+*/
+static void tokenListToIdList(char **azIn){
+  int i, j;
+  if( azIn ){
+    for(i=0, j=-1; azIn[i]; i++){
+      if( safe_isalnum(azIn[i][0]) || azIn[i][1] ){
+        dequoteString(azIn[i]);
+        if( j>=0 ){
+          azIn[j] = azIn[i];
+        }
+        j++;
+      }
+    }
+    azIn[j] = 0;
   }
 }
 
-static int endsInWhiteSpace(StringBuffer *p){
-  return stringBufferLength(p)>0 &&
-    safe_isspace(stringBufferData(p)[stringBufferLength(p)-1]);
-}
 
-/* If the StringBuffer ends in something other than white space, add a
-** single space character to the end.
+/*
+** Find the first alphanumeric token in the string zIn.  Null-terminate
+** this token.  Remove any quotation marks.  And return a pointer to
+** the result.
 */
-static void appendWhiteSpace(StringBuffer *p){
-  if( stringBufferLength(p)==0 ) return;
-  if( !endsInWhiteSpace(p) ) append(p, " ");
-}
-
-/* Remove white space from the end of the StringBuffer */
-static void trimWhiteSpace(StringBuffer *p){
-  while( endsInWhiteSpace(p) ){
-    p->b.pData[--p->b.nData-1] = '\0';
+static char *firstToken(char *zIn, char **pzTail){
+  int n, ttype;
+  while(1){
+    n = ftsGetToken(zIn, &ttype);
+    if( ttype==TOKEN_SPACE ){
+      zIn += n;
+    }else if( ttype==TOKEN_EOF ){
+      *pzTail = zIn;
+      return 0;
+    }else{
+      zIn[n] = 0;
+      *pzTail = &zIn[1];
+      dequoteString(zIn);
+      return zIn;
+    }
   }
+  /*NOTREACHED*/
 }
 
-/*******************************************************************/
-/* DLReader is used to read document elements from a doclist.  The
-** current docid is cached, so dlrDocid() is fast.  DLReader does not
-** own the doclist buffer.
-**
-** dlrAtEnd - true if there's no more data to read.
-** dlrDocid - docid of current document.
-** dlrDocData - doclist data for current document (including docid).
-** dlrDocDataBytes - length of same.
-** dlrAllDataBytes - length of all remaining data.
-** dlrPosData - position data for current document.
-** dlrPosDataLen - length of pos data for current document (incl POS_END).
-** dlrStep - step to current document.
-** dlrInit - initial for doclist of given type against given data.
-** dlrDestroy - clean up.
+/* Return true if...
 **
-** Expected usage is something like:
+**   *  s begins with the string t, ignoring case
+**   *  s is longer than t
+**   *  The first character of s beyond t is not a alphanumeric
+** 
+** Ignore leading space in *s.
 **
-**   DLReader reader;
-**   dlrInit(&reader, pData, nData);
-**   while( !dlrAtEnd(&reader) ){
-**     // calls to dlrDocid() and kin.
-**     dlrStep(&reader);
-**   }
-**   dlrDestroy(&reader);
+** To put it another way, return true if the first token of
+** s[] is t[].
 */
-typedef struct DLReader {
-  DocListType iType;
-  const char *pData;
-  int nData;
+static int startsWith(const char *s, const char *t){
+  while( safe_isspace(*s) ){ s++; }
+  while( *t ){
+    if( safe_tolower(*s++)!=safe_tolower(*t++) ) return 0;
+  }
+  return *s!='_' && !safe_isalnum(*s);
+}
 
-  sqlite_int64 iDocid;
-  int nElement;
-} DLReader;
+/*
+** An instance of this structure defines the "spec" of a
+** full text index.  This structure is populated by parseSpec
+** and use by fulltextConnect and fulltextCreate.
+*/
+typedef struct TableSpec {
+  const char *zDb;         /* Logical database name */
+  const char *zName;       /* Name of the full-text index */
+  int nColumn;             /* Number of columns to be indexed */
+  char **azColumn;         /* Original names of columns to be indexed */
+  char **azContentColumn;  /* Column names for %_content */
+  char **azTokenizer;      /* Name of tokenizer and its arguments */
+} TableSpec;
 
-static int dlrAtEnd(DLReader *pReader){
-  assert( pReader->nData>=0 );
-  return pReader->nData==0;
-}
-static sqlite_int64 dlrDocid(DLReader *pReader){
-  assert( !dlrAtEnd(pReader) );
-  return pReader->iDocid;
-}
-static const char *dlrDocData(DLReader *pReader){
-  assert( !dlrAtEnd(pReader) );
-  return pReader->pData;
-}
-static int dlrDocDataBytes(DLReader *pReader){
-  assert( !dlrAtEnd(pReader) );
-  return pReader->nElement;
-}
-static int dlrAllDataBytes(DLReader *pReader){
-  assert( !dlrAtEnd(pReader) );
-  return pReader->nData;
-}
-/* TODO(shess) Consider adding a field to track iDocid varint length
-** to make these two functions faster.  This might matter (a tiny bit)
-** for queries.
+/*
+** Reclaim all of the memory used by a TableSpec
 */
-static const char *dlrPosData(DLReader *pReader){
-  sqlite_int64 iDummy;
-  int n = fts3GetVarint(pReader->pData, &iDummy);
-  assert( !dlrAtEnd(pReader) );
-  return pReader->pData+n;
-}
-static int dlrPosDataLen(DLReader *pReader){
-  sqlite_int64 iDummy;
-  int n = fts3GetVarint(pReader->pData, &iDummy);
-  assert( !dlrAtEnd(pReader) );
-  return pReader->nElement-n;
+static void clearTableSpec(TableSpec *p) {
+  sqlite3_free(p->azColumn);
+  sqlite3_free(p->azContentColumn);
+  sqlite3_free(p->azTokenizer);
 }
-static void dlrStep(DLReader *pReader){
-  assert( !dlrAtEnd(pReader) );
 
-  /* Skip past current doclist element. */
-  assert( pReader->nElement<=pReader->nData );
-  pReader->pData += pReader->nElement;
-  pReader->nData -= pReader->nElement;
+/* Parse a CREATE VIRTUAL TABLE statement, which looks like this:
+ *
+ * CREATE VIRTUAL TABLE email
+ *        USING fts3(subject, body, tokenize mytokenizer(myarg))
+ *
+ * We return parsed information in a TableSpec structure.
+ * 
+ */
+static int parseSpec(TableSpec *pSpec, int argc, const char *const*argv,
+                     char**pzErr){
+  int i, n;
+  char *z, *zDummy;
+  char **azArg;
+  const char *zTokenizer = 0;    /* argv[] entry describing the tokenizer */
 
-  /* If there is more data, read the next doclist element. */
-  if( pReader->nData!=0 ){
-    sqlite_int64 iDocidDelta;
-    int iDummy, n = fts3GetVarint(pReader->pData, &iDocidDelta);
-    pReader->iDocid += iDocidDelta;
-    if( pReader->iType>=DL_POSITIONS ){
-      assert( nnData );
-      while( 1 ){
-        n += fts3GetVarint32(pReader->pData+n, &iDummy);
-        assert( n<=pReader->nData );
-        if( iDummy==POS_END ) break;
-        if( iDummy==POS_COLUMN ){
-          n += fts3GetVarint32(pReader->pData+n, &iDummy);
-          assert( nnData );
-        }else if( pReader->iType==DL_POSITIONS_OFFSETS ){
-          n += fts3GetVarint32(pReader->pData+n, &iDummy);
-          n += fts3GetVarint32(pReader->pData+n, &iDummy);
-          assert( nnData );
-        }
-      }
-    }
-    pReader->nElement = n;
-    assert( pReader->nElement<=pReader->nData );
+  assert( argc>=3 );
+  /* Current interface:
+  ** argv[0] - module name
+  ** argv[1] - database name
+  ** argv[2] - table name
+  ** argv[3..] - columns, optionally followed by tokenizer specification
+  **             and snippet delimiters specification.
+  */
+
+  /* Make a copy of the complete argv[][] array in a single allocation.
+  ** The argv[][] array is read-only and transient.  We can write to the
+  ** copy in order to modify things and the copy is persistent.
+  */
+  CLEAR(pSpec);
+  for(i=n=0; iiType = iType;
-  pReader->pData = pData;
-  pReader->nData = nData;
-  pReader->nElement = 0;
-  pReader->iDocid = 0;
 
-  /* Load the first element's data.  There must be a first element. */
-  dlrStep(pReader);
-}
-static void dlrDestroy(DLReader *pReader){
-  SCRAMBLE(pReader);
-}
+  /* Identify the column names and the tokenizer and delimiter arguments
+  ** in the argv[][] array.
+  */
+  pSpec->zDb = azArg[1];
+  pSpec->zName = azArg[2];
+  pSpec->nColumn = 0;
+  pSpec->azColumn = azArg;
+  zTokenizer = "tokenize simple";
+  for(i=3; inColumn] = firstToken(azArg[i], &zDummy);
+      pSpec->nColumn++;
+    }
+  }
+  if( pSpec->nColumn==0 ){
+    azArg[0] = "content";
+    pSpec->nColumn = 1;
+  }
 
-#ifndef NDEBUG
-/* Verify that the doclist can be validly decoded.  Also returns the
-** last docid found because it is convenient in other assertions for
-** DLWriter.
-*/
-static void docListValidate(DocListType iType, const char *pData, int nData,
-                            sqlite_int64 *pLastDocid){
-  sqlite_int64 iPrevDocid = 0;
-  assert( nData>0 );
-  assert( pData!=0 );
-  assert( pData+nData>pData );
-  while( nData!=0 ){
-    sqlite_int64 iDocidDelta;
-    int n = fts3GetVarint(pData, &iDocidDelta);
-    iPrevDocid += iDocidDelta;
-    if( iType>DL_DOCIDS ){
-      int iDummy;
-      while( 1 ){
-        n += fts3GetVarint32(pData+n, &iDummy);
-        if( iDummy==POS_END ) break;
-        if( iDummy==POS_COLUMN ){
-          n += fts3GetVarint32(pData+n, &iDummy);
-        }else if( iType>DL_POSITIONS ){
-          n += fts3GetVarint32(pData+n, &iDummy);
-          n += fts3GetVarint32(pData+n, &iDummy);
-        }
-        assert( n<=nData );
-      }
+  /*
+  ** Construct the list of content column names.
+  **
+  ** Each content column name will be of the form cNNAAAA
+  ** where NN is the column number and AAAA is the sanitized
+  ** column name.  "sanitized" means that special characters are
+  ** converted to "_".  The cNN prefix guarantees that all column
+  ** names are unique.
+  **
+  ** The AAAA suffix is not strictly necessary.  It is included
+  ** for the convenience of people who might examine the generated
+  ** %_content table and wonder what the columns are used for.
+  */
+  pSpec->azContentColumn = sqlite3_malloc( pSpec->nColumn * sizeof(char *) );
+  if( pSpec->azContentColumn==0 ){
+    clearTableSpec(pSpec);
+    return SQLITE_NOMEM;
+  }
+  for(i=0; inColumn; i++){
+    char *p;
+    pSpec->azContentColumn[i] = sqlite3_mprintf("c%d%s", i, azArg[i]);
+    for (p = pSpec->azContentColumn[i]; *p ; ++p) {
+      if( !safe_isalnum(*p) ) *p = '_';
     }
-    assert( n<=nData );
-    pData += n;
-    nData -= n;
   }
-  if( pLastDocid ) *pLastDocid = iPrevDocid;
-}
-#define ASSERT_VALID_DOCLIST(i, p, n, o) docListValidate(i, p, n, o)
-#else
-#define ASSERT_VALID_DOCLIST(i, p, n, o) assert( 1 )
-#endif
 
-/*******************************************************************/
-/* DLWriter is used to write doclist data to a DataBuffer.  DLWriter
-** always appends to the buffer and does not own it.
-**
-** dlwInit - initialize to write a given type doclistto a buffer.
-** dlwDestroy - clear the writer's memory.  Does not free buffer.
-** dlwAppend - append raw doclist data to buffer.
-** dlwCopy - copy next doclist from reader to writer.
-** dlwAdd - construct doclist element and append to buffer.
-**    Only apply dlwAdd() to DL_DOCIDS doclists (else use PLWriter).
-*/
-typedef struct DLWriter {
-  DocListType iType;
-  DataBuffer *b;
-  sqlite_int64 iPrevDocid;
-#ifndef NDEBUG
-  int has_iPrevDocid;
-#endif
-} DLWriter;
+  /*
+  ** Parse the tokenizer specification string.
+  */
+  pSpec->azTokenizer = tokenizeString(zTokenizer, &n);
+  tokenListToIdList(pSpec->azTokenizer);
 
-static void dlwInit(DLWriter *pWriter, DocListType iType, DataBuffer *b){
-  pWriter->b = b;
-  pWriter->iType = iType;
-  pWriter->iPrevDocid = 0;
-#ifndef NDEBUG
-  pWriter->has_iPrevDocid = 0;
-#endif
-}
-static void dlwDestroy(DLWriter *pWriter){
-  SCRAMBLE(pWriter);
+  return SQLITE_OK;
 }
-/* iFirstDocid is the first docid in the doclist in pData.  It is
-** needed because pData may point within a larger doclist, in which
-** case the first item would be delta-encoded.
+
+/*
+** Generate a CREATE TABLE statement that describes the schema of
+** the virtual table.  Return a pointer to this schema string.
 **
-** iLastDocid is the final docid in the doclist in pData.  It is
-** needed to create the new iPrevDocid for future delta-encoding.  The
-** code could decode the passed doclist to recreate iLastDocid, but
-** the only current user (docListMerge) already has decoded this
-** information.
+** Space is obtained from sqlite3_mprintf() and should be freed
+** using sqlite3_free().
 */
-/* TODO(shess) This has become just a helper for docListMerge.
-** Consider a refactor to make this cleaner.
+static char *fulltextSchema(
+  int nColumn,                  /* Number of columns */
+  const char *const* azColumn,  /* List of columns */
+  const char *zTableName        /* Name of the table */
+){
+  int i;
+  char *zSchema, *zNext;
+  const char *zSep = "(";
+  zSchema = sqlite3_mprintf("CREATE TABLE x");
+  for(i=0; iiType==DL_DOCIDS) );
-  nFirstNew = fts3PutVarint(c, iFirstDocid-pWriter->iPrevDocid);
+  char const *zTok;         /* Name of tokenizer to use for this fts table */
+  int nTok;                 /* Length of zTok, including nul terminator */
 
-  /* Verify that the incoming doclist is valid AND that it ends with
-  ** the expected docid.  This is essential because we'll trust this
-  ** docid in future delta-encoding.
-  */
-  ASSERT_VALID_DOCLIST(pWriter->iType, pData, nData, &iLastDocidDelta);
-  assert( iLastDocid==iFirstDocid-iDocid+iLastDocidDelta );
+  v = (fulltext_vtab *) sqlite3_malloc(sizeof(fulltext_vtab));
+  if( v==0 ) return SQLITE_NOMEM;
+  CLEAR(v);
+  /* sqlite will initialize v->base */
+  v->db = db;
+  v->zDb = spec->zDb;       /* Freed when azColumn is freed */
+  v->zName = spec->zName;   /* Freed when azColumn is freed */
+  v->nColumn = spec->nColumn;
+  v->azContentColumn = spec->azContentColumn;
+  spec->azContentColumn = 0;
+  v->azColumn = spec->azColumn;
+  spec->azColumn = 0;
 
-  /* Append recoded initial docid and everything else.  Rest of docids
-  ** should have been delta-encoded from previous initial docid.
-  */
-  if( nFirstOldb, c, nFirstNew,
-                      pData+nFirstOld, nData-nFirstOld);
+  if( spec->azTokenizer==0 ){
+    return SQLITE_NOMEM;
+  }
+
+  zTok = spec->azTokenizer[0]; 
+  if( !zTok ){
+    zTok = "simple";
+  }
+  nTok = strlen(zTok)+1;
+
+  m = (sqlite3_tokenizer_module *)sqlite3Fts3HashFind(pHash, zTok, nTok);
+  if( !m ){
+    *pzErr = sqlite3_mprintf("unknown tokenizer: %s", spec->azTokenizer[0]);
+    rc = SQLITE_ERROR;
+    goto err;
+  }
+
+  for(n=0; spec->azTokenizer[n]; n++){}
+  if( n ){
+    rc = m->xCreate(n-1, (const char*const*)&spec->azTokenizer[1],
+                    &v->pTokenizer);
   }else{
-    dataBufferAppend(pWriter->b, c, nFirstNew);
+    rc = m->xCreate(0, 0, &v->pTokenizer);
   }
-  pWriter->iPrevDocid = iLastDocid;
-}
-static void dlwCopy(DLWriter *pWriter, DLReader *pReader){
-  dlwAppend(pWriter, dlrDocData(pReader), dlrDocDataBytes(pReader),
-            dlrDocid(pReader), dlrDocid(pReader));
+  if( rc!=SQLITE_OK ) goto err;
+  v->pTokenizer->pModule = m;
+
+  /* TODO: verify the existence of backing tables foo_content, foo_term */
+
+  schema = fulltextSchema(v->nColumn, (const char*const*)v->azColumn,
+                          spec->zName);
+  rc = sqlite3_declare_vtab(db, schema);
+  sqlite3_free(schema);
+  if( rc!=SQLITE_OK ) goto err;
+
+  memset(v->pFulltextStatements, 0, sizeof(v->pFulltextStatements));
+
+  /* Indicate that the buffer is not live. */
+  v->nPendingData = -1;
+
+  *ppVTab = &v->base;
+  FTSTRACE(("FTS3 Connect %p\n", v));
+
+  return rc;
+
+err:
+  fulltext_vtab_destroy(v);
+  return rc;
 }
-static void dlwAdd(DLWriter *pWriter, sqlite_int64 iDocid){
-  char c[VARINT_MAX];
-  int n = fts3PutVarint(c, iDocid-pWriter->iPrevDocid);
 
-  /* Docids must ascend. */
-  assert( !pWriter->has_iPrevDocid || iDocid>pWriter->iPrevDocid );
-  assert( pWriter->iType==DL_DOCIDS );
+static int fulltextConnect(
+  sqlite3 *db,
+  void *pAux,
+  int argc, const char *const*argv,
+  sqlite3_vtab **ppVTab,
+  char **pzErr
+){
+  TableSpec spec;
+  int rc = parseSpec(&spec, argc, argv, pzErr);
+  if( rc!=SQLITE_OK ) return rc;
 
-  dataBufferAppend(pWriter->b, c, n);
-  pWriter->iPrevDocid = iDocid;
-#ifndef NDEBUG
-  pWriter->has_iPrevDocid = 1;
-#endif
+  rc = constructVtab(db, (fts3Hash *)pAux, &spec, ppVTab, pzErr);
+  clearTableSpec(&spec);
+  return rc;
 }
 
-/*******************************************************************/
-/* PLReader is used to read data from a document's position list.  As
-** the caller steps through the list, data is cached so that varints
-** only need to be decoded once.
-**
-** plrInit, plrDestroy - create/destroy a reader.
-** plrColumn, plrPosition, plrStartOffset, plrEndOffset - accessors
-** plrAtEnd - at end of stream, only call plrDestroy once true.
-** plrStep - step to the next element.
+/* The %_content table holds the text of each document, with
+** the docid column exposed as the SQLite rowid for the table.
 */
-typedef struct PLReader {
-  /* These refer to the next position's data.  nData will reach 0 when
-  ** reading the last position, so plrStep() signals EOF by setting
-  ** pData to NULL.
-  */
-  const char *pData;
-  int nData;
+/* TODO(shess) This comment needs elaboration to match the updated
+** code.  Work it into the top-of-file comment at that time.
+*/
+static int fulltextCreate(sqlite3 *db, void *pAux,
+                          int argc, const char * const *argv,
+                          sqlite3_vtab **ppVTab, char **pzErr){
+  int rc;
+  TableSpec spec;
+  StringBuffer schema;
+  FTSTRACE(("FTS3 Create\n"));
+
+  rc = parseSpec(&spec, argc, argv, pzErr);
+  if( rc!=SQLITE_OK ) return rc;
+
+  initStringBuffer(&schema);
+  append(&schema, "CREATE TABLE %_content(");
+  append(&schema, "  docid INTEGER PRIMARY KEY,");
+  appendList(&schema, spec.nColumn, spec.azContentColumn);
+  append(&schema, ")");
+  rc = sql_exec(db, spec.zDb, spec.zName, stringBufferData(&schema));
+  stringBufferDestroy(&schema);
+  if( rc!=SQLITE_OK ) goto out;
+
+  rc = sql_exec(db, spec.zDb, spec.zName,
+                "create table %_segments("
+                "  blockid INTEGER PRIMARY KEY,"
+                "  block blob"
+                ");"
+                );
+  if( rc!=SQLITE_OK ) goto out;
 
-  DocListType iType;
-  int iColumn;         /* the last column read */
-  int iPosition;       /* the last position read */
-  int iStartOffset;    /* the last start offset read */
-  int iEndOffset;      /* the last end offset read */
-} PLReader;
+  rc = sql_exec(db, spec.zDb, spec.zName,
+                "create table %_segdir("
+                "  level integer,"
+                "  idx integer,"
+                "  start_block integer,"
+                "  leaves_end_block integer,"
+                "  end_block integer,"
+                "  root blob,"
+                "  primary key(level, idx)"
+                ");");
+  if( rc!=SQLITE_OK ) goto out;
 
-static int plrAtEnd(PLReader *pReader){
-  return pReader->pData==NULL;
-}
-static int plrColumn(PLReader *pReader){
-  assert( !plrAtEnd(pReader) );
-  return pReader->iColumn;
-}
-static int plrPosition(PLReader *pReader){
-  assert( !plrAtEnd(pReader) );
-  return pReader->iPosition;
-}
-static int plrStartOffset(PLReader *pReader){
-  assert( !plrAtEnd(pReader) );
-  return pReader->iStartOffset;
-}
-static int plrEndOffset(PLReader *pReader){
-  assert( !plrAtEnd(pReader) );
-  return pReader->iEndOffset;
+  rc = constructVtab(db, (fts3Hash *)pAux, &spec, ppVTab, pzErr);
+
+out:
+  clearTableSpec(&spec);
+  return rc;
 }
-static void plrStep(PLReader *pReader){
-  int i, n;
 
-  assert( !plrAtEnd(pReader) );
+/* Decide how to handle an SQL query. */
+static int fulltextBestIndex(sqlite3_vtab *pVTab, sqlite3_index_info *pInfo){
+  fulltext_vtab *v = (fulltext_vtab *)pVTab;
+  int i;
+  FTSTRACE(("FTS3 BestIndex\n"));
 
-  if( pReader->nData==0 ){
-    pReader->pData = NULL;
-    return;
-  }
+  for(i=0; inConstraint; ++i){
+    const struct sqlite3_index_constraint *pConstraint;
+    pConstraint = &pInfo->aConstraint[i];
+    if( pConstraint->usable ) {
+      if( (pConstraint->iColumn==-1 || pConstraint->iColumn==v->nColumn+1) &&
+          pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ ){
+        pInfo->idxNum = QUERY_DOCID;      /* lookup by docid */
+        FTSTRACE(("FTS3 QUERY_DOCID\n"));
+      } else if( pConstraint->iColumn>=0 && pConstraint->iColumn<=v->nColumn &&
+                 pConstraint->op==SQLITE_INDEX_CONSTRAINT_MATCH ){
+        /* full-text search */
+        pInfo->idxNum = QUERY_FULLTEXT + pConstraint->iColumn;
+        FTSTRACE(("FTS3 QUERY_FULLTEXT %d\n", pConstraint->iColumn));
+      } else continue;
 
-  n = fts3GetVarint32(pReader->pData, &i);
-  if( i==POS_COLUMN ){
-    n += fts3GetVarint32(pReader->pData+n, &pReader->iColumn);
-    pReader->iPosition = 0;
-    pReader->iStartOffset = 0;
-    n += fts3GetVarint32(pReader->pData+n, &i);
-  }
-  /* Should never see adjacent column changes. */
-  assert( i!=POS_COLUMN );
+      pInfo->aConstraintUsage[i].argvIndex = 1;
+      pInfo->aConstraintUsage[i].omit = 1;
 
-  if( i==POS_END ){
-    pReader->nData = 0;
-    pReader->pData = NULL;
-    return;
-  }
+      /* An arbitrary value for now.
+       * TODO: Perhaps docid matches should be considered cheaper than
+       * full-text searches. */
+      pInfo->estimatedCost = 1.0;   
 
-  pReader->iPosition += i-POS_BASE;
-  if( pReader->iType==DL_POSITIONS_OFFSETS ){
-    n += fts3GetVarint32(pReader->pData+n, &i);
-    pReader->iStartOffset += i;
-    n += fts3GetVarint32(pReader->pData+n, &i);
-    pReader->iEndOffset = pReader->iStartOffset+i;
+      return SQLITE_OK;
+    }
   }
-  assert( n<=pReader->nData );
-  pReader->pData += n;
-  pReader->nData -= n;
+  pInfo->idxNum = QUERY_GENERIC;
+  return SQLITE_OK;
 }
 
-static void plrInit(PLReader *pReader, DLReader *pDLReader){
-  pReader->pData = dlrPosData(pDLReader);
-  pReader->nData = dlrPosDataLen(pDLReader);
-  pReader->iType = pDLReader->iType;
-  pReader->iColumn = 0;
-  pReader->iPosition = 0;
-  pReader->iStartOffset = 0;
-  pReader->iEndOffset = 0;
-  plrStep(pReader);
-}
-static void plrDestroy(PLReader *pReader){
-  SCRAMBLE(pReader);
+static int fulltextDisconnect(sqlite3_vtab *pVTab){
+  FTSTRACE(("FTS3 Disconnect %p\n", pVTab));
+  fulltext_vtab_destroy((fulltext_vtab *)pVTab);
+  return SQLITE_OK;
 }
 
-/*******************************************************************/
-/* PLWriter is used in constructing a document's position list.  As a
-** convenience, if iType is DL_DOCIDS, PLWriter becomes a no-op.
-** PLWriter writes to the associated DLWriter's buffer.
-**
-** plwInit - init for writing a document's poslist.
-** plwDestroy - clear a writer.
-** plwAdd - append position and offset information.
-** plwCopy - copy next position's data from reader to writer.
-** plwTerminate - add any necessary doclist terminator.
-**
-** Calling plwAdd() after plwTerminate() may result in a corrupt
-** doclist.
-*/
-/* TODO(shess) Until we've written the second item, we can cache the
-** first item's information.  Then we'd have three states:
-**
-** - initialized with docid, no positions.
-** - docid and one position.
-** - docid and multiple positions.
-**
-** Only the last state needs to actually write to dlw->b, which would
-** be an improvement in the DLCollector case.
-*/
-typedef struct PLWriter {
-  DLWriter *dlw;
-
-  int iColumn;    /* the last column written */
-  int iPos;       /* the last position written */
-  int iOffset;    /* the last start offset written */
-} PLWriter;
+static int fulltextDestroy(sqlite3_vtab *pVTab){
+  fulltext_vtab *v = (fulltext_vtab *)pVTab;
+  int rc;
 
-/* TODO(shess) In the case where the parent is reading these values
-** from a PLReader, we could optimize to a copy if that PLReader has
-** the same type as pWriter.
-*/
-static void plwAdd(PLWriter *pWriter, int iColumn, int iPos,
-                   int iStartOffset, int iEndOffset){
-  /* Worst-case space for POS_COLUMN, iColumn, iPosDelta,
-  ** iStartOffsetDelta, and iEndOffsetDelta.
-  */
-  char c[5*VARINT_MAX];
-  int n = 0;
+  FTSTRACE(("FTS3 Destroy %p\n", pVTab));
+  rc = sql_exec(v->db, v->zDb, v->zName,
+                "drop table if exists %_content;"
+                "drop table if exists %_segments;"
+                "drop table if exists %_segdir;"
+                );
+  if( rc!=SQLITE_OK ) return rc;
 
-  /* Ban plwAdd() after plwTerminate(). */
-  assert( pWriter->iPos!=-1 );
+  fulltext_vtab_destroy((fulltext_vtab *)pVTab);
+  return SQLITE_OK;
+}
 
-  if( pWriter->dlw->iType==DL_DOCIDS ) return;
+static int fulltextOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
+  fulltext_cursor *c;
 
-  if( iColumn!=pWriter->iColumn ){
-    n += fts3PutVarint(c+n, POS_COLUMN);
-    n += fts3PutVarint(c+n, iColumn);
-    pWriter->iColumn = iColumn;
-    pWriter->iPos = 0;
-    pWriter->iOffset = 0;
-  }
-  assert( iPos>=pWriter->iPos );
-  n += fts3PutVarint(c+n, POS_BASE+(iPos-pWriter->iPos));
-  pWriter->iPos = iPos;
-  if( pWriter->dlw->iType==DL_POSITIONS_OFFSETS ){
-    assert( iStartOffset>=pWriter->iOffset );
-    n += fts3PutVarint(c+n, iStartOffset-pWriter->iOffset);
-    pWriter->iOffset = iStartOffset;
-    assert( iEndOffset>=iStartOffset );
-    n += fts3PutVarint(c+n, iEndOffset-iStartOffset);
+  c = (fulltext_cursor *) sqlite3_malloc(sizeof(fulltext_cursor));
+  if( c ){
+    memset(c, 0, sizeof(fulltext_cursor));
+    /* sqlite will initialize c->base */
+    *ppCursor = &c->base;
+    FTSTRACE(("FTS3 Open %p: %p\n", pVTab, c));
+    return SQLITE_OK;
+  }else{
+    return SQLITE_NOMEM;
   }
-  dataBufferAppend(pWriter->dlw->b, c, n);
-}
-static void plwCopy(PLWriter *pWriter, PLReader *pReader){
-  plwAdd(pWriter, plrColumn(pReader), plrPosition(pReader),
-         plrStartOffset(pReader), plrEndOffset(pReader));
 }
-static void plwInit(PLWriter *pWriter, DLWriter *dlw, sqlite_int64 iDocid){
-  char c[VARINT_MAX];
-  int n;
 
-  pWriter->dlw = dlw;
 
-  /* Docids must ascend. */
-  assert( !pWriter->dlw->has_iPrevDocid || iDocid>pWriter->dlw->iPrevDocid );
-  n = fts3PutVarint(c, iDocid-pWriter->dlw->iPrevDocid);
-  dataBufferAppend(pWriter->dlw->b, c, n);
-  pWriter->dlw->iPrevDocid = iDocid;
-#ifndef NDEBUG
-  pWriter->dlw->has_iPrevDocid = 1;
-#endif
+/* Free all of the dynamically allocated memory held by *q
+*/
+static void queryClear(Query *q){
+  int i;
+  for(i = 0; i < q->nTerms; ++i){
+    sqlite3_free(q->pTerms[i].pTerm);
+  }
+  sqlite3_free(q->pTerms);
+  CLEAR(q);
+}
 
-  pWriter->iColumn = 0;
-  pWriter->iPos = 0;
-  pWriter->iOffset = 0;
+/* Free all of the dynamically allocated memory held by the
+** Snippet
+*/
+static void snippetClear(Snippet *p){
+  sqlite3_free(p->aMatch);
+  sqlite3_free(p->zOffset);
+  sqlite3_free(p->zSnippet);
+  CLEAR(p);
 }
-/* TODO(shess) Should plwDestroy() also terminate the doclist?  But
-** then plwDestroy() would no longer be just a destructor, it would
-** also be doing work, which isn't consistent with the overall idiom.
-** Another option would be for plwAdd() to always append any necessary
-** terminator, so that the output is always correct.  But that would
-** add incremental work to the common case with the only benefit being
-** API elegance.  Punt for now.
+/*
+** Append a single entry to the p->aMatch[] log.
 */
-static void plwTerminate(PLWriter *pWriter){
-  if( pWriter->dlw->iType>DL_DOCIDS ){
-    char c[VARINT_MAX];
-    int n = fts3PutVarint(c, POS_END);
-    dataBufferAppend(pWriter->dlw->b, c, n);
+static void snippetAppendMatch(
+  Snippet *p,               /* Append the entry to this snippet */
+  int iCol, int iTerm,      /* The column and query term */
+  int iToken,               /* Matching token in document */
+  int iStart, int nByte     /* Offset and size of the match */
+){
+  int i;
+  struct snippetMatch *pMatch;
+  if( p->nMatch+1>=p->nAlloc ){
+    p->nAlloc = p->nAlloc*2 + 10;
+    p->aMatch = sqlite3_realloc(p->aMatch, p->nAlloc*sizeof(p->aMatch[0]) );
+    if( p->aMatch==0 ){
+      p->nMatch = 0;
+      p->nAlloc = 0;
+      return;
+    }
   }
-#ifndef NDEBUG
-  /* Mark as terminated for assert in plwAdd(). */
-  pWriter->iPos = -1;
-#endif
-}
-static void plwDestroy(PLWriter *pWriter){
-  SCRAMBLE(pWriter);
+  i = p->nMatch++;
+  pMatch = &p->aMatch[i];
+  pMatch->iCol = iCol;
+  pMatch->iTerm = iTerm;
+  pMatch->iToken = iToken;
+  pMatch->iStart = iStart;
+  pMatch->nByte = nByte;
 }
 
-/*******************************************************************/
-/* DLCollector wraps PLWriter and DLWriter to provide a
-** dynamically-allocated doclist area to use during tokenization.
-**
-** dlcNew - malloc up and initialize a collector.
-** dlcDelete - destroy a collector and all contained items.
-** dlcAddPos - append position and offset information.
-** dlcAddDoclist - add the collected doclist to the given buffer.
-** dlcNext - terminate the current document and open another.
+/*
+** Sizing information for the circular buffer used in snippetOffsetsOfColumn()
 */
-typedef struct DLCollector {
-  DataBuffer b;
-  DLWriter dlw;
-  PLWriter plw;
-} DLCollector;
+#define FTS3_ROTOR_SZ   (32)
+#define FTS3_ROTOR_MASK (FTS3_ROTOR_SZ-1)
 
-/* TODO(shess) This could also be done by calling plwTerminate() and
-** dataBufferAppend().  I tried that, expecting nominal performance
-** differences, but it seemed to pretty reliably be worth 1% to code
-** it this way.  I suspect it is the incremental malloc overhead (some
-** percentage of the plwTerminate() calls will cause a realloc), so
-** this might be worth revisiting if the DataBuffer implementation
-** changes.
+/*
+** Add entries to pSnippet->aMatch[] for every match that occurs against
+** document zDoc[0..nDoc-1] which is stored in column iColumn.
 */
-static void dlcAddDoclist(DLCollector *pCollector, DataBuffer *b){
-  if( pCollector->dlw.iType>DL_DOCIDS ){
-    char c[VARINT_MAX];
-    int n = fts3PutVarint(c, POS_END);
-    dataBufferAppend2(b, pCollector->b.pData, pCollector->b.nData, c, n);
-  }else{
-    dataBufferAppend(b, pCollector->b.pData, pCollector->b.nData);
-  }
-}
-static void dlcNext(DLCollector *pCollector, sqlite_int64 iDocid){
-  plwTerminate(&pCollector->plw);
-  plwDestroy(&pCollector->plw);
-  plwInit(&pCollector->plw, &pCollector->dlw, iDocid);
-}
-static void dlcAddPos(DLCollector *pCollector, int iColumn, int iPos,
-                      int iStartOffset, int iEndOffset){
-  plwAdd(&pCollector->plw, iColumn, iPos, iStartOffset, iEndOffset);
-}
+static void snippetOffsetsOfColumn(
+  Query *pQuery,
+  Snippet *pSnippet,
+  int iColumn,
+  const char *zDoc,
+  int nDoc
+){
+  const sqlite3_tokenizer_module *pTModule;  /* The tokenizer module */
+  sqlite3_tokenizer *pTokenizer;             /* The specific tokenizer */
+  sqlite3_tokenizer_cursor *pTCursor;        /* Tokenizer cursor */
+  fulltext_vtab *pVtab;                /* The full text index */
+  int nColumn;                         /* Number of columns in the index */
+  const QueryTerm *aTerm;              /* Query string terms */
+  int nTerm;                           /* Number of query string terms */  
+  int i, j;                            /* Loop counters */
+  int rc;                              /* Return code */
+  unsigned int match, prevMatch;       /* Phrase search bitmasks */
+  const char *zToken;                  /* Next token from the tokenizer */
+  int nToken;                          /* Size of zToken */
+  int iBegin, iEnd, iPos;              /* Offsets of beginning and end */
 
-static DLCollector *dlcNew(sqlite_int64 iDocid, DocListType iType){
-  DLCollector *pCollector = sqlite3_malloc(sizeof(DLCollector));
-  dataBufferInit(&pCollector->b, 0);
-  dlwInit(&pCollector->dlw, iType, &pCollector->b);
-  plwInit(&pCollector->plw, &pCollector->dlw, iDocid);
-  return pCollector;
-}
-static void dlcDelete(DLCollector *pCollector){
-  plwDestroy(&pCollector->plw);
-  dlwDestroy(&pCollector->dlw);
-  dataBufferDestroy(&pCollector->b);
-  SCRAMBLE(pCollector);
-  sqlite3_free(pCollector);
-}
+  /* The following variables keep a circular buffer of the last
+  ** few tokens */
+  unsigned int iRotor = 0;             /* Index of current token */
+  int iRotorBegin[FTS3_ROTOR_SZ];      /* Beginning offset of token */
+  int iRotorLen[FTS3_ROTOR_SZ];        /* Length of token */
 
+  pVtab = pQuery->pFts;
+  nColumn = pVtab->nColumn;
+  pTokenizer = pVtab->pTokenizer;
+  pTModule = pTokenizer->pModule;
+  rc = pTModule->xOpen(pTokenizer, zDoc, nDoc, &pTCursor);
+  if( rc ) return;
+  pTCursor->pTokenizer = pTokenizer;
+  aTerm = pQuery->pTerms;
+  nTerm = pQuery->nTerms;
+  if( nTerm>=FTS3_ROTOR_SZ ){
+    nTerm = FTS3_ROTOR_SZ - 1;
+  }
+  prevMatch = 0;
+  while(1){
+    rc = pTModule->xNext(pTCursor, &zToken, &nToken, &iBegin, &iEnd, &iPos);
+    if( rc ) break;
+    iRotorBegin[iRotor&FTS3_ROTOR_MASK] = iBegin;
+    iRotorLen[iRotor&FTS3_ROTOR_MASK] = iEnd-iBegin;
+    match = 0;
+    for(i=0; i=0 && iColnToken ) continue;
+      if( !aTerm[i].isPrefix && aTerm[i].nTerm1 && (prevMatch & (1<=0; j--){
+          int k = (iRotor-j) & FTS3_ROTOR_MASK;
+          snippetAppendMatch(pSnippet, iColumn, i-j, iPos-j,
+                iRotorBegin[k], iRotorLen[k]);
+        }
+      }
+    }
+    prevMatch = match<<1;
+    iRotor++;
+  }
+  pTModule->xClose(pTCursor);  
+}
 
-/* Copy the doclist data of iType in pData/nData into *out, trimming
-** unnecessary data as we go.  Only columns matching iColumn are
-** copied, all columns copied if iColumn is -1.  Elements with no
-** matching columns are dropped.  The output is an iOutType doclist.
-*/
-/* NOTE(shess) This code is only valid after all doclists are merged.
-** If this is run before merges, then doclist items which represent
-** deletion will be trimmed, and will thus not effect a deletion
-** during the merge.
+/*
+** Remove entries from the pSnippet structure to account for the NEAR
+** operator. When this is called, pSnippet contains the list of token 
+** offsets produced by treating all NEAR operators as AND operators.
+** This function removes any entries that should not be present after
+** accounting for the NEAR restriction. For example, if the queried
+** document is:
+**
+**     "A B C D E A"
+**
+** and the query is:
+** 
+**     A NEAR/0 E
+**
+** then when this function is called the Snippet contains token offsets
+** 0, 4 and 5. This function removes the "0" entry (because the first A
+** is not near enough to an E).
 */
-static void docListTrim(DocListType iType, const char *pData, int nData,
-                        int iColumn, DocListType iOutType, DataBuffer *out){
-  DLReader dlReader;
-  DLWriter dlWriter;
+static void trimSnippetOffsetsForNear(Query *pQuery, Snippet *pSnippet){
+  int ii;
+  int iDir = 1;
 
-  assert( iOutType<=iType );
+  while(iDir>-2) {
+    assert( iDir==1 || iDir==-1 );
+    for(ii=0; iinMatch; ii++){
+      int jj;
+      int nNear;
+      struct snippetMatch *pMatch = &pSnippet->aMatch[ii];
+      QueryTerm *pQueryTerm = &pQuery->pTerms[pMatch->iTerm];
 
-  dlrInit(&dlReader, iType, pData, nData);
-  dlwInit(&dlWriter, iOutType, out);
+      if( (pMatch->iTerm+iDir)<0 
+       || (pMatch->iTerm+iDir)>=pQuery->nTerms
+      ){
+        continue;
+      }
+     
+      nNear = pQueryTerm->nNear;
+      if( iDir<0 ){
+        nNear = pQueryTerm[-1].nNear;
+      }
+  
+      if( pMatch->iTerm>=0 && nNear ){
+        int isOk = 0;
+        int iNextTerm = pMatch->iTerm+iDir;
+        int iPrevTerm = iNextTerm;
 
-  while( !dlrAtEnd(&dlReader) ){
-    PLReader plReader;
-    PLWriter plWriter;
-    int match = 0;
+        int iEndToken;
+        int iStartToken;
 
-    plrInit(&plReader, &dlReader);
+        if( iDir<0 ){
+          int nPhrase = 1;
+          iStartToken = pMatch->iToken;
+          while( (pMatch->iTerm+nPhrase)nTerms 
+              && pQuery->pTerms[pMatch->iTerm+nPhrase].iPhrase>1 
+          ){
+            nPhrase++;
+          }
+          iEndToken = iStartToken + nPhrase - 1;
+        }else{
+          iEndToken   = pMatch->iToken;
+          iStartToken = pMatch->iToken+1-pQueryTerm->iPhrase;
+        }
 
-    while( !plrAtEnd(&plReader) ){
-      if( iColumn==-1 || plrColumn(&plReader)==iColumn ){
-        if( !match ){
-          plwInit(&plWriter, &dlWriter, dlrDocid(&dlReader));
-          match = 1;
+        while( pQuery->pTerms[iNextTerm].iPhrase>1 ){
+          iNextTerm--;
+        }
+        while( (iPrevTerm+1)nTerms && 
+               pQuery->pTerms[iPrevTerm+1].iPhrase>1 
+        ){
+          iPrevTerm++;
+        }
+  
+        for(jj=0; isOk==0 && jjnMatch; jj++){
+          struct snippetMatch *p = &pSnippet->aMatch[jj];
+          if( p->iCol==pMatch->iCol && ((
+               p->iTerm==iNextTerm && 
+               p->iToken>iEndToken && 
+               p->iToken<=iEndToken+nNear
+          ) || (
+               p->iTerm==iPrevTerm && 
+               p->iTokeniToken>=iStartToken-nNear
+          ))){
+            isOk = 1;
+          }
+        }
+        if( !isOk ){
+          for(jj=1-pQueryTerm->iPhrase; jj<=0; jj++){
+            pMatch[jj].iTerm = -1;
+          }
+          ii = -1;
+          iDir = 1;
         }
-        plwAdd(&plWriter, plrColumn(&plReader), plrPosition(&plReader),
-               plrStartOffset(&plReader), plrEndOffset(&plReader));
       }
-      plrStep(&plReader);
-    }
-    if( match ){
-      plwTerminate(&plWriter);
-      plwDestroy(&plWriter);
     }
-
-    plrDestroy(&plReader);
-    dlrStep(&dlReader);
+    iDir -= 2;
   }
-  dlwDestroy(&dlWriter);
-  dlrDestroy(&dlReader);
 }
 
-/* Used by docListMerge() to keep doclists in the ascending order by
-** docid, then ascending order by age (so the newest comes first).
+/*
+** Compute all offsets for the current row of the query.  
+** If the offsets have already been computed, this routine is a no-op.
 */
-typedef struct OrderedDLReader {
-  DLReader *pReader;
-
-  /* TODO(shess) If we assume that docListMerge pReaders is ordered by
-  ** age (which we do), then we could use pReader comparisons to break
-  ** ties.
-  */
-  int idx;
-} OrderedDLReader;
+static void snippetAllOffsets(fulltext_cursor *p){
+  int nColumn;
+  int iColumn, i;
+  int iFirst, iLast;
+  fulltext_vtab *pFts;
 
-/* Order eof to end, then by docid asc, idx desc. */
-static int orderedDLReaderCmp(OrderedDLReader *r1, OrderedDLReader *r2){
-  if( dlrAtEnd(r1->pReader) ){
-    if( dlrAtEnd(r2->pReader) ) return 0;  /* Both atEnd(). */
-    return 1;                              /* Only r1 atEnd(). */
+  if( p->snippet.nMatch ) return;
+  if( p->q.nTerms==0 ) return;
+  pFts = p->q.pFts;
+  nColumn = pFts->nColumn;
+  iColumn = (p->iCursorType - QUERY_FULLTEXT);
+  if( iColumn<0 || iColumn>=nColumn ){
+    iFirst = 0;
+    iLast = nColumn-1;
+  }else{
+    iFirst = iColumn;
+    iLast = iColumn;
+  }
+  for(i=iFirst; i<=iLast; i++){
+    const char *zDoc;
+    int nDoc;
+    zDoc = (const char*)sqlite3_column_text(p->pStmt, i+1);
+    nDoc = sqlite3_column_bytes(p->pStmt, i+1);
+    snippetOffsetsOfColumn(&p->q, &p->snippet, i, zDoc, nDoc);
   }
-  if( dlrAtEnd(r2->pReader) ) return -1;   /* Only r2 atEnd(). */
-
-  if( dlrDocid(r1->pReader)pReader) ) return -1;
-  if( dlrDocid(r1->pReader)>dlrDocid(r2->pReader) ) return 1;
 
-  /* Descending on idx. */
-  return r2->idx-r1->idx;
+  trimSnippetOffsetsForNear(&p->q, &p->snippet);
 }
 
-/* Bubble p[0] to appropriate place in p[1..n-1].  Assumes that
-** p[1..n-1] is already sorted.
-*/
-/* TODO(shess) Is this frequent enough to warrant a binary search?
-** Before implementing that, instrument the code to check.  In most
-** current usage, I expect that p[0] will be less than p[1] a very
-** high proportion of the time.
+/*
+** Convert the information in the aMatch[] array of the snippet
+** into the string zOffset[0..nOffset-1].
 */
-static void orderedDLReaderReorder(OrderedDLReader *p, int n){
-  while( n>1 && orderedDLReaderCmp(p, p+1)>0 ){
-    OrderedDLReader tmp = p[0];
-    p[0] = p[1];
-    p[1] = tmp;
-    n--;
-    p++;
+static void snippetOffsetText(Snippet *p){
+  int i;
+  int cnt = 0;
+  StringBuffer sb;
+  char zBuf[200];
+  if( p->zOffset ) return;
+  initStringBuffer(&sb);
+  for(i=0; inMatch; i++){
+    struct snippetMatch *pMatch = &p->aMatch[i];
+    if( pMatch->iTerm>=0 ){
+      /* If snippetMatch.iTerm is less than 0, then the match was 
+      ** discarded as part of processing the NEAR operator (see the 
+      ** trimSnippetOffsetsForNear() function for details). Ignore 
+      ** it in this case
+      */
+      zBuf[0] = ' ';
+      sqlite3_snprintf(sizeof(zBuf)-1, &zBuf[cnt>0], "%d %d %d %d",
+          pMatch->iCol, pMatch->iTerm, pMatch->iStart, pMatch->nByte);
+      append(&sb, zBuf);
+      cnt++;
+    }
   }
+  p->zOffset = stringBufferData(&sb);
+  p->nOffset = stringBufferLength(&sb);
 }
 
-/* Given an array of doclist readers, merge their doclist elements
-** into out in sorted order (by docid), dropping elements from older
-** readers when there is a duplicate docid.  pReaders is assumed to be
-** ordered by age, oldest first.
-*/
-/* TODO(shess) nReaders must be <= MERGE_COUNT.  This should probably
-** be fixed.
+/*
+** zDoc[0..nDoc-1] is phrase of text.  aMatch[0..nMatch-1] are a set
+** of matching words some of which might be in zDoc.  zDoc is column
+** number iCol.
+**
+** iBreak is suggested spot in zDoc where we could begin or end an
+** excerpt.  Return a value similar to iBreak but possibly adjusted
+** to be a little left or right so that the break point is better.
 */
-static void docListMerge(DataBuffer *out,
-                         DLReader *pReaders, int nReaders){
-  OrderedDLReader readers[MERGE_COUNT];
-  DLWriter writer;
-  int i, n;
-  const char *pStart = 0;
-  int nStart = 0;
-  sqlite_int64 iFirstDocid = 0, iLastDocid = 0;
-
-  assert( nReaders>0 );
-  if( nReaders==1 ){
-    dataBufferAppend(out, dlrDocData(pReaders), dlrAllDataBytes(pReaders));
-    return;
-  }
-
-  assert( nReaders<=MERGE_COUNT );
-  n = 0;
-  for(i=0; i0 ){
-    orderedDLReaderReorder(readers+i, nReaders-i);
+  if( iBreak>=nDoc-10 ){
+    return nDoc;
   }
-
-  dlwInit(&writer, pReaders[0].iType, out);
-  while( !dlrAtEnd(readers[0].pReader) ){
-    sqlite_int64 iDocid = dlrDocid(readers[0].pReader);
-
-    /* If this is a continuation of the current buffer to copy, extend
-    ** that buffer.  memcpy() seems to be more efficient if it has a
-    ** lots of data to copy.
-    */
-    if( dlrDocData(readers[0].pReader)==pStart+nStart ){
-      nStart += dlrDocDataBytes(readers[0].pReader);
-    }else{
-      if( pStart!=0 ){
-        dlwAppend(&writer, pStart, nStart, iFirstDocid, iLastDocid);
-      }
-      pStart = dlrDocData(readers[0].pReader);
-      nStart = dlrDocDataBytes(readers[0].pReader);
-      iFirstDocid = iDocid;
+  for(i=0; i0 && aMatch[i-1].iStart+aMatch[i-1].nByte>=iBreak ){
+      return aMatch[i-1].iStart;
     }
-
-    /* Get the readers back into order. */
-    while( i-->0 ){
-      orderedDLReaderReorder(readers+i, nReaders-i);
+  }
+  for(i=1; i<=10; i++){
+    if( safe_isspace(zDoc[iBreak-i]) ){
+      return iBreak - i + 1;
+    }
+    if( safe_isspace(zDoc[iBreak+i]) ){
+      return iBreak + i + 1;
     }
   }
-
-  /* Copy over any remaining elements. */
-  if( nStart>0 ) dlwAppend(&writer, pStart, nStart, iFirstDocid, iLastDocid);
-  dlwDestroy(&writer);
+  return iBreak;
 }
 
-/* Helper function for posListUnion().  Compares the current position
-** between left and right, returning as standard C idiom of <0 if
-** left0 if left>right, and 0 if left==right.  "End" always
-** compares greater.
-*/
-static int posListCmp(PLReader *pLeft, PLReader *pRight){
-  assert( pLeft->iType==pRight->iType );
-  if( pLeft->iType==DL_DOCIDS ) return 0;
-
-  if( plrAtEnd(pLeft) ) return plrAtEnd(pRight) ? 0 : 1;
-  if( plrAtEnd(pRight) ) return -1;
-
-  if( plrColumn(pLeft)plrColumn(pRight) ) return 1;
-
-  if( plrPosition(pLeft)plrPosition(pRight) ) return 1;
-  if( pLeft->iType==DL_POSITIONS ) return 0;
-
-  if( plrStartOffset(pLeft)plrStartOffset(pRight) ) return 1;
 
-  if( plrEndOffset(pLeft)plrEndOffset(pRight) ) return 1;
 
-  return 0;
-}
+/*
+** Allowed values for Snippet.aMatch[].snStatus
+*/
+#define SNIPPET_IGNORE  0   /* It is ok to omit this match from the snippet */
+#define SNIPPET_DESIRED 1   /* We want to include this match in the snippet */
 
-/* Write the union of position lists in pLeft and pRight to pOut.
-** "Union" in this case meaning "All unique position tuples".  Should
-** work with any doclist type, though both inputs and the output
-** should be the same type.
+/*
+** Generate the text of a snippet.
 */
-static void posListUnion(DLReader *pLeft, DLReader *pRight, DLWriter *pOut){
-  PLReader left, right;
-  PLWriter writer;
+static void snippetText(
+  fulltext_cursor *pCursor,   /* The cursor we need the snippet for */
+  const char *zStartMark,     /* Markup to appear before each match */
+  const char *zEndMark,       /* Markup to appear after each match */
+  const char *zEllipsis       /* Ellipsis mark */
+){
+  int i, j;
+  struct snippetMatch *aMatch;
+  int nMatch;
+  int nDesired;
+  StringBuffer sb;
+  int tailCol;
+  int tailOffset;
+  int iCol;
+  int nDoc;
+  const char *zDoc;
+  int iStart, iEnd;
+  int tailEllipsis = 0;
+  int iMatch;
+  
 
-  assert( dlrDocid(pLeft)==dlrDocid(pRight) );
-  assert( pLeft->iType==pRight->iType );
-  assert( pLeft->iType==pOut->iType );
+  sqlite3_free(pCursor->snippet.zSnippet);
+  pCursor->snippet.zSnippet = 0;
+  aMatch = pCursor->snippet.aMatch;
+  nMatch = pCursor->snippet.nMatch;
+  initStringBuffer(&sb);
 
-  plrInit(&left, pLeft);
-  plrInit(&right, pRight);
-  plwInit(&writer, pOut, dlrDocid(pLeft));
+  for(i=0; iq.nTerms; i++){
+    for(j=0; j0 ){
-      plwCopy(&writer, &right);
-      plrStep(&right);
+  iMatch = 0;
+  tailCol = -1;
+  tailOffset = 0;
+  for(i=0; i0; i++){
+    if( aMatch[i].snStatus!=SNIPPET_DESIRED ) continue;
+    nDesired--;
+    iCol = aMatch[i].iCol;
+    zDoc = (const char*)sqlite3_column_text(pCursor->pStmt, iCol+1);
+    nDoc = sqlite3_column_bytes(pCursor->pStmt, iCol+1);
+    iStart = aMatch[i].iStart - 40;
+    iStart = wordBoundary(iStart, zDoc, nDoc, aMatch, nMatch, iCol);
+    if( iStart<=10 ){
+      iStart = 0;
+    }
+    if( iCol==tailCol && iStart<=tailOffset+20 ){
+      iStart = tailOffset;
+    }
+    if( (iCol!=tailCol && tailCol>=0) || iStart!=tailOffset ){
+      trimWhiteSpace(&sb);
+      appendWhiteSpace(&sb);
+      append(&sb, zEllipsis);
+      appendWhiteSpace(&sb);
+    }
+    iEnd = aMatch[i].iStart + aMatch[i].nByte + 40;
+    iEnd = wordBoundary(iEnd, zDoc, nDoc, aMatch, nMatch, iCol);
+    if( iEnd>=nDoc-10 ){
+      iEnd = nDoc;
+      tailEllipsis = 0;
     }else{
-      plwCopy(&writer, &left);
-      plrStep(&left);
-      plrStep(&right);
+      tailEllipsis = 1;
+    }
+    while( iMatchsnippet.zSnippet = stringBufferData(&sb);
+  pCursor->snippet.nSnippet = stringBufferLength(&sb);
 }
 
-/* Write the union of doclists in pLeft and pRight to pOut.  For
-** docids in common between the inputs, the union of the position
-** lists is written.  Inputs and outputs are always type DL_DEFAULT.
+
+/*
+** Close the cursor.  For additional information see the documentation
+** on the xClose method of the virtual table interface.
 */
-static void docListUnion(
-  const char *pLeft, int nLeft,
-  const char *pRight, int nRight,
-  DataBuffer *pOut      /* Write the combined doclist here */
-){
-  DLReader left, right;
-  DLWriter writer;
+static int fulltextClose(sqlite3_vtab_cursor *pCursor){
+  fulltext_cursor *c = (fulltext_cursor *) pCursor;
+  FTSTRACE(("FTS3 Close %p\n", c));
+  sqlite3_finalize(c->pStmt);
+  queryClear(&c->q);
+  snippetClear(&c->snippet);
+  if( c->result.nData!=0 ) dlrDestroy(&c->reader);
+  dataBufferDestroy(&c->result);
+  sqlite3_free(c);
+  return SQLITE_OK;
+}
 
-  if( nLeft==0 ){
-    if( nRight!=0) dataBufferAppend(pOut, pRight, nRight);
-    return;
-  }
-  if( nRight==0 ){
-    dataBufferAppend(pOut, pLeft, nLeft);
-    return;
-  }
+static int fulltextNext(sqlite3_vtab_cursor *pCursor){
+  fulltext_cursor *c = (fulltext_cursor *) pCursor;
+  int rc;
 
-  dlrInit(&left, DL_DEFAULT, pLeft, nLeft);
-  dlrInit(&right, DL_DEFAULT, pRight, nRight);
-  dlwInit(&writer, DL_DEFAULT, pOut);
+  FTSTRACE(("FTS3 Next %p\n", pCursor));
+  snippetClear(&c->snippet);
+  if( c->iCursorType < QUERY_FULLTEXT ){
+    /* TODO(shess) Handle SQLITE_SCHEMA AND SQLITE_BUSY. */
+    rc = sqlite3_step(c->pStmt);
+    switch( rc ){
+      case SQLITE_ROW:
+        c->eof = 0;
+        return SQLITE_OK;
+      case SQLITE_DONE:
+        c->eof = 1;
+        return SQLITE_OK;
+      default:
+        c->eof = 1;
+        return rc;
+    }
+  } else {  /* full-text query */
+    rc = sqlite3_reset(c->pStmt);
+    if( rc!=SQLITE_OK ) return rc;
 
-  while( !dlrAtEnd(&left) || !dlrAtEnd(&right) ){
-    if( dlrAtEnd(&right) ){
-      dlwCopy(&writer, &left);
-      dlrStep(&left);
-    }else if( dlrAtEnd(&left) ){
-      dlwCopy(&writer, &right);
-      dlrStep(&right);
-    }else if( dlrDocid(&left)dlrDocid(&right) ){
-      dlwCopy(&writer, &right);
-      dlrStep(&right);
-    }else{
-      posListUnion(&left, &right, &writer);
-      dlrStep(&left);
-      dlrStep(&right);
+    if( c->result.nData==0 || dlrAtEnd(&c->reader) ){
+      c->eof = 1;
+      return SQLITE_OK;
+    }
+    rc = sqlite3_bind_int64(c->pStmt, 1, dlrDocid(&c->reader));
+    dlrStep(&c->reader);
+    if( rc!=SQLITE_OK ) return rc;
+    /* TODO(shess) Handle SQLITE_SCHEMA AND SQLITE_BUSY. */
+    rc = sqlite3_step(c->pStmt);
+    if( rc==SQLITE_ROW ){   /* the case we expect */
+      c->eof = 0;
+      return SQLITE_OK;
     }
+    /* an error occurred; abort */
+    return rc==SQLITE_DONE ? SQLITE_ERROR : rc;
   }
-
-  dlrDestroy(&left);
-  dlrDestroy(&right);
-  dlwDestroy(&writer);
 }
 
-/* 
-** This function is used as part of the implementation of phrase and
-** NEAR matching.
-**
-** pLeft and pRight are DLReaders positioned to the same docid in
-** lists of type DL_POSITION. This function writes an entry to the
-** DLWriter pOut for each position in pRight that is less than
-** (nNear+1) greater (but not equal to or smaller) than a position 
-** in pLeft. For example, if nNear is 0, and the positions contained
-** by pLeft and pRight are:
-**
-**    pLeft:  5 10 15 20
-**    pRight: 6  9 17 21
-**
-** then the docid is added to pOut. If pOut is of type DL_POSITIONS,
-** then a positionids "6" and "21" are also added to pOut.
-**
-** If boolean argument isSaveLeft is true, then positionids are copied
-** from pLeft instead of pRight. In the example above, the positions "5"
-** and "20" would be added instead of "6" and "21".
+
+/* TODO(shess) If we pushed LeafReader to the top of the file, or to
+** another file, term_select() could be pushed above
+** docListOfTerm().
 */
-static void posListPhraseMerge(
-  DLReader *pLeft, 
-  DLReader *pRight,
-  int nNear,
-  int isSaveLeft,
-  DLWriter *pOut
+static int termSelect(fulltext_vtab *v, int iColumn,
+                      const char *pTerm, int nTerm, int isPrefix,
+                      DocListType iType, DataBuffer *out);
+
+/* Return a DocList corresponding to the query term *pTerm.  If *pTerm
+** is the first term of a phrase query, go ahead and evaluate the phrase
+** query and return the doclist for the entire phrase query.
+**
+** The resulting DL_DOCIDS doclist is stored in pResult, which is
+** overwritten.
+*/
+static int docListOfTerm(
+  fulltext_vtab *v,    /* The full text index */
+  int iColumn,         /* column to restrict to.  No restriction if >=nColumn */
+  QueryTerm *pQTerm,   /* Term we are looking for, or 1st term of a phrase */
+  DataBuffer *pResult  /* Write the result here */
 ){
-  PLReader left, right;
-  PLWriter writer;
-  int match = 0;
+  DataBuffer left, right, new;
+  int i, rc;
 
-  assert( dlrDocid(pLeft)==dlrDocid(pRight) );
-  assert( pOut->iType!=DL_POSITIONS_OFFSETS );
+  /* No phrase search if no position info. */
+  assert( pQTerm->nPhrase==0 || DL_DEFAULT!=DL_DOCIDS );
 
-  plrInit(&left, pLeft);
-  plrInit(&right, pRight);
+  /* This code should never be called with buffered updates. */
+  assert( v->nPendingData<0 );
 
-  while( !plrAtEnd(&left) && !plrAtEnd(&right) ){
-    if( plrColumn(&left)plrColumn(&right) ){
-      plrStep(&right);
-    }else if( plrPosition(&left)>=plrPosition(&right) ){
-      plrStep(&right);
-    }else{
-      if( (plrPosition(&right)-plrPosition(&left))<=(nNear+1) ){
-        if( !match ){
-          plwInit(&writer, pOut, dlrDocid(pLeft));
-          match = 1;
-        }
-        if( !isSaveLeft ){
-          plwAdd(&writer, plrColumn(&right), plrPosition(&right), 0, 0);
-        }else{
-          plwAdd(&writer, plrColumn(&left), plrPosition(&left), 0, 0);
-        }
-        plrStep(&right);
-      }else{
-        plrStep(&left);
-      }
+  dataBufferInit(&left, 0);
+  rc = termSelect(v, iColumn, pQTerm->pTerm, pQTerm->nTerm, pQTerm->isPrefix,
+                  (0nPhrase ? DL_POSITIONS : DL_DOCIDS), &left);
+  if( rc ) return rc;
+  for(i=1; i<=pQTerm->nPhrase && left.nData>0; i++){
+    /* If this token is connected to the next by a NEAR operator, and
+    ** the next token is the start of a phrase, then set nPhraseRight
+    ** to the number of tokens in the phrase. Otherwise leave it at 1.
+    */
+    int nPhraseRight = 1;
+    while( (i+nPhraseRight)<=pQTerm->nPhrase 
+        && pQTerm[i+nPhraseRight].nNear==0 
+    ){
+      nPhraseRight++;
     }
-  }
 
-  if( match ){
-    plwTerminate(&writer);
-    plwDestroy(&writer);
+    dataBufferInit(&right, 0);
+    rc = termSelect(v, iColumn, pQTerm[i].pTerm, pQTerm[i].nTerm,
+                    pQTerm[i].isPrefix, DL_POSITIONS, &right);
+    if( rc ){
+      dataBufferDestroy(&left);
+      return rc;
+    }
+    dataBufferInit(&new, 0);
+    docListPhraseMerge(left.pData, left.nData, right.pData, right.nData,
+                       pQTerm[i-1].nNear, pQTerm[i-1].iPhrase + nPhraseRight,
+                       ((inPhrase) ? DL_POSITIONS : DL_DOCIDS),
+                       &new);
+    dataBufferDestroy(&left);
+    dataBufferDestroy(&right);
+    left = new;
   }
+  *pResult = left;
+  return SQLITE_OK;
+}
 
-  plrDestroy(&left);
-  plrDestroy(&right);
+/* Add a new term pTerm[0..nTerm-1] to the query *q.
+*/
+static void queryAdd(Query *q, const char *pTerm, int nTerm){
+  QueryTerm *t;
+  ++q->nTerms;
+  q->pTerms = sqlite3_realloc(q->pTerms, q->nTerms * sizeof(q->pTerms[0]));
+  if( q->pTerms==0 ){
+    q->nTerms = 0;
+    return;
+  }
+  t = &q->pTerms[q->nTerms - 1];
+  CLEAR(t);
+  t->pTerm = sqlite3_malloc(nTerm+1);
+  memcpy(t->pTerm, pTerm, nTerm);
+  t->pTerm[nTerm] = 0;
+  t->nTerm = nTerm;
+  t->isOr = q->nextIsOr;
+  t->isPrefix = 0;
+  q->nextIsOr = 0;
+  t->iColumn = q->nextColumn;
+  q->nextColumn = q->dfltColumn;
 }
 
 /*
-** Compare the values pointed to by the PLReaders passed as arguments. 
-** Return -1 if the value pointed to by pLeft is considered less than
-** the value pointed to by pRight, +1 if it is considered greater
-** than it, or 0 if it is equal. i.e.
-**
-**     (*pLeft - *pRight)
-**
-** A PLReader that is in the EOF condition is considered greater than
-** any other. If neither argument is in EOF state, the return value of
-** plrColumn() is used. If the plrColumn() values are equal, the
-** comparison is on the basis of plrPosition().
+** Check to see if the string zToken[0...nToken-1] matches any
+** column name in the virtual table.   If it does,
+** return the zero-indexed column number.  If not, return -1.
 */
-static int plrCompare(PLReader *pLeft, PLReader *pRight){
-  assert(!plrAtEnd(pLeft) || !plrAtEnd(pRight));
-
-  if( plrAtEnd(pRight) || plrAtEnd(pLeft) ){
-    return (plrAtEnd(pRight) ? -1 : 1);
-  }
-  if( plrColumn(pLeft)!=plrColumn(pRight) ){
-    return ((plrColumn(pLeft)nColumn; i++){
+    if( memcmp(pVtab->azColumn[i], zToken, nToken)==0
+        && pVtab->azColumn[i][nToken]==0 ){
+      return i;
+    }
   }
-  return 0;
+  return -1;
 }
 
-/* We have two doclists with positions:  pLeft and pRight. Depending
-** on the value of the nNear parameter, perform either a phrase
-** intersection (if nNear==0) or a NEAR intersection (if nNear>0)
-** and write the results into pOut.
-**
-** A phrase intersection means that two documents only match
-** if pLeft.iPos+1==pRight.iPos.
-**
-** A NEAR intersection means that two documents only match if 
-** (abs(pLeft.iPos-pRight.iPos)pModule;
+  sqlite3_tokenizer_cursor *pCursor;
+  int firstIndex = pQuery->nTerms;
+  int iCol;
+  int nTerm = 1;
+  
+  int rc = pModule->xOpen(pTokenizer, zSegment, nSegment, &pCursor);
+  if( rc!=SQLITE_OK ) return rc;
+  pCursor->pTokenizer = pTokenizer;
 
-          PLWriter plwriter;
-          plwInit(&plwriter, &writer, dlrDocid(dlrAtEnd(&dr1)?&dr2:&dr1));
+  while( 1 ){
+    const char *zToken;
+    int nToken, iBegin, iEnd, iPos;
 
-          if( one.nData ) plrInit(&pr1, &dr1);
-          if( two.nData ) plrInit(&pr2, &dr2);
-          while( !plrAtEnd(&pr1) || !plrAtEnd(&pr2) ){
-            int iCompare = plrCompare(&pr1, &pr2);
-            switch( iCompare ){
-              case -1:
-                plwCopy(&plwriter, &pr1);
-                plrStep(&pr1);
-                break;
-              case 1:
-                plwCopy(&plwriter, &pr2);
-                plrStep(&pr2);
-                break;
-              case 0:
-                plwCopy(&plwriter, &pr1);
-                plrStep(&pr1);
-                plrStep(&pr2);
-                break;
-            }
-          }
-          plwTerminate(&plwriter);
+    rc = pModule->xNext(pCursor,
+                        &zToken, &nToken,
+                        &iBegin, &iEnd, &iPos);
+    if( rc!=SQLITE_OK ) break;
+    if( !inPhrase &&
+        zSegment[iEnd]==':' &&
+         (iCol = checkColumnSpecifier(pQuery->pFts, zToken, nToken))>=0 ){
+      pQuery->nextColumn = iCol;
+      continue;
+    }
+    if( !inPhrase && pQuery->nTerms>0 && nToken==2 
+     && zSegment[iBegin+0]=='O'
+     && zSegment[iBegin+1]=='R' 
+    ){
+      pQuery->nextIsOr = 1;
+      continue;
+    }
+    if( !inPhrase && pQuery->nTerms>0 && !pQuery->nextIsOr && nToken==4 
+      && memcmp(&zSegment[iBegin], "NEAR", 4)==0
+    ){
+      QueryTerm *pTerm = &pQuery->pTerms[pQuery->nTerms-1];
+      if( (iBegin+6)nNear = 0;
+        for(k=5; (iBegin+k)<=nSegment && isdigit(zSegment[iBegin+k]); k++){
+          pTerm->nNear = pTerm->nNear*10 + (zSegment[iBegin+k] - '0');
         }
-        dataBufferDestroy(&one);
-        dataBufferDestroy(&two);
+        pModule->xNext(pCursor, &zToken, &nToken, &iBegin, &iEnd, &iPos);
+      } else {
+        pTerm->nNear = SQLITE_FTS3_DEFAULT_NEAR_PARAM;
       }
-      dlrStep(&left);
-      dlrStep(&right);
+      pTerm->nNear++;
+      continue;
+    }
+
+    queryAdd(pQuery, zToken, nToken);
+    if( !inPhrase && iBegin>0 && zSegment[iBegin-1]=='-' ){
+      pQuery->pTerms[pQuery->nTerms-1].isNot = 1;
+    }
+    if( iEndpTerms[pQuery->nTerms-1].isPrefix = 1;
+    }
+    pQuery->pTerms[pQuery->nTerms-1].iPhrase = nTerm;
+    if( inPhrase ){
+      nTerm++;
     }
   }
 
-  dlrDestroy(&left);
-  dlrDestroy(&right);
-  dlwDestroy(&writer);
+  if( inPhrase && pQuery->nTerms>firstIndex ){
+    pQuery->pTerms[firstIndex].nPhrase = pQuery->nTerms - firstIndex - 1;
+  }
+
+  return pModule->xClose(pCursor);
 }
 
-/* We have two DL_DOCIDS doclists:  pLeft and pRight.
-** Write the intersection of these two doclists into pOut as a
-** DL_DOCIDS doclist.
+/* Parse a query string, yielding a Query object pQuery.
+**
+** The calling function will need to queryClear() to clean up
+** the dynamically allocated memory held by pQuery.
 */
-static void docListAndMerge(
-  const char *pLeft, int nLeft,
-  const char *pRight, int nRight,
-  DataBuffer *pOut      /* Write the combined doclist here */
+static int parseQuery(
+  fulltext_vtab *v,        /* The fulltext index */
+  const char *zInput,      /* Input text of the query string */
+  int nInput,              /* Size of the input text */
+  int dfltColumn,          /* Default column of the index to match against */
+  Query *pQuery            /* Write the parse results here. */
 ){
-  DLReader left, right;
-  DLWriter writer;
-
-  if( nLeft==0 || nRight==0 ) return;
+  int iInput, inPhrase = 0;
+  int ii;
+  QueryTerm *aTerm;
 
-  dlrInit(&left, DL_DOCIDS, pLeft, nLeft);
-  dlrInit(&right, DL_DOCIDS, pRight, nRight);
-  dlwInit(&writer, DL_DOCIDS, pOut);
+  if( zInput==0 ) nInput = 0;
+  if( nInput<0 ) nInput = strlen(zInput);
+  pQuery->nTerms = 0;
+  pQuery->pTerms = NULL;
+  pQuery->nextIsOr = 0;
+  pQuery->nextColumn = dfltColumn;
+  pQuery->dfltColumn = dfltColumn;
+  pQuery->pFts = v;
 
-  while( !dlrAtEnd(&left) && !dlrAtEnd(&right) ){
-    if( dlrDocid(&left)iInput ){
+      tokenizeSegment(v->pTokenizer, zInput+iInput, i-iInput, inPhrase,
+                       pQuery);
+    }
+    iInput = i;
+    if( ipTerms;
+  for(ii=0; iinTerms; ii++){
+    if( aTerm[ii].nNear || aTerm[ii].nPhrase ){
+      while (aTerm[ii+aTerm[ii].nPhrase].nNear) {
+        aTerm[ii].nPhrase += (1 + aTerm[ii+aTerm[ii].nPhrase+1].nPhrase);
+      }
     }
   }
 
-  dlrDestroy(&left);
-  dlrDestroy(&right);
-  dlwDestroy(&writer);
+  return SQLITE_OK;
 }
 
-/* We have two DL_DOCIDS doclists:  pLeft and pRight.
-** Write into pOut as DL_DOCIDS doclist containing all documents that
-** occur in pLeft but not in pRight.
+/* TODO(shess) Refactor the code to remove this forward decl. */
+static int flushPendingTerms(fulltext_vtab *v);
+
+/* Perform a full-text query using the search expression in
+** zInput[0..nInput-1].  Return a list of matching documents
+** in pResult.
+**
+** Queries must match column iColumn.  Or if iColumn>=nColumn
+** they are allowed to match against any column.
 */
-static void docListExceptMerge(
-  const char *pLeft, int nLeft,
-  const char *pRight, int nRight,
-  DataBuffer *pOut      /* Write the combined doclist here */
+static int fulltextQuery(
+  fulltext_vtab *v,      /* The full text index */
+  int iColumn,           /* Match against this column by default */
+  const char *zInput,    /* The query string */
+  int nInput,            /* Number of bytes in zInput[] */
+  DataBuffer *pResult,   /* Write the result doclist here */
+  Query *pQuery          /* Put parsed query string here */
 ){
-  DLReader left, right;
-  DLWriter writer;
+  int i, iNext, rc;
+  DataBuffer left, right, or, new;
+  int nNot = 0;
+  QueryTerm *aTerm;
 
-  if( nLeft==0 ) return;
-  if( nRight==0 ){
-    dataBufferAppend(pOut, pLeft, nLeft);
-    return;
-  }
+  /* TODO(shess) Instead of flushing pendingTerms, we could query for
+  ** the relevant term and merge the doclist into what we receive from
+  ** the database.  Wait and see if this is a common issue, first.
+  **
+  ** A good reason not to flush is to not generate update-related
+  ** error codes from here.
+  */
 
-  dlrInit(&left, DL_DOCIDS, pLeft, nLeft);
-  dlrInit(&right, DL_DOCIDS, pRight, nRight);
-  dlwInit(&writer, DL_DOCIDS, pOut);
+  /* Flush any buffered updates before executing the query. */
+  rc = flushPendingTerms(v);
+  if( rc!=SQLITE_OK ) return rc;
 
-  while( !dlrAtEnd(&left) ){
-    while( !dlrAtEnd(&right) && dlrDocid(&right)nTerms==0 ){
+    dataBufferInit(pResult, 0);
+    return SQLITE_OK;
+  }
+
+  /* Merge AND terms. */
+  /* TODO(shess) I think we can early-exit if( i>nNot && left.nData==0 ). */
+  aTerm = pQuery->pTerms;
+  for(i = 0; inTerms; i=iNext){
+    if( aTerm[i].isNot ){
+      /* Handle all NOT terms in a separate pass */
+      nNot++;
+      iNext = i + aTerm[i].nPhrase+1;
+      continue;
     }
-    if( dlrAtEnd(&right) || dlrDocid(&left)nTerms && aTerm[iNext].isOr ){
+      rc = docListOfTerm(v, aTerm[iNext].iColumn, &aTerm[iNext], &or);
+      iNext += aTerm[iNext].nPhrase + 1;
+      if( rc ){
+        if( i!=nNot ) dataBufferDestroy(&left);
+        dataBufferDestroy(&right);
+        queryClear(pQuery);
+        return rc;
+      }
+      dataBufferInit(&new, 0);
+      docListOrMerge(right.pData, right.nData, or.pData, or.nData, &new);
+      dataBufferDestroy(&right);
+      dataBufferDestroy(&or);
+      right = new;
+    }
+    if( i==nNot ){           /* first term processed. */
+      left = right;
+    }else{
+      dataBufferInit(&new, 0);
+      docListAndMerge(left.pData, left.nData, right.pData, right.nData, &new);
+      dataBufferDestroy(&right);
+      dataBufferDestroy(&left);
+      left = new;
     }
-    dlrStep(&left);
   }
 
-  dlrDestroy(&left);
-  dlrDestroy(&right);
-  dlwDestroy(&writer);
-}
-
-static char *string_dup_n(const char *s, int n){
-  char *str = sqlite3_malloc(n + 1);
-  memcpy(str, s, n);
-  str[n] = '\0';
-  return str;
-}
-
-/* Duplicate a string; the caller must free() the returned string.
- * (We don't use strdup() since it is not part of the standard C library and
- * may not be available everywhere.) */
-static char *string_dup(const char *s){
-  return string_dup_n(s, strlen(s));
-}
-
-/* Format a string, replacing each occurrence of the % character with
- * zDb.zName.  This may be more convenient than sqlite_mprintf()
- * when one string is used repeatedly in a format string.
- * The caller must free() the returned string. */
-static char *string_format(const char *zFormat,
-                           const char *zDb, const char *zName){
-  const char *p;
-  size_t len = 0;
-  size_t nDb = strlen(zDb);
-  size_t nName = strlen(zName);
-  size_t nFullTableName = nDb+1+nName;
-  char *result;
-  char *r;
-
-  /* first compute length needed */
-  for(p = zFormat ; *p ; ++p){
-    len += (*p=='%' ? nFullTableName : 1);
+  if( nNot==pQuery->nTerms ){
+    /* We do not yet know how to handle a query of only NOT terms */
+    return SQLITE_ERROR;
   }
-  len += 1;  /* for null terminator */
 
-  r = result = sqlite3_malloc(len);
-  for(p = zFormat; *p; ++p){
-    if( *p=='%' ){
-      memcpy(r, zDb, nDb);
-      r += nDb;
-      *r++ = '.';
-      memcpy(r, zName, nName);
-      r += nName;
-    } else {
-      *r++ = *p;
+  /* Do the EXCEPT terms */
+  for(i=0; inTerms;  i += aTerm[i].nPhrase + 1){
+    if( !aTerm[i].isNot ) continue;
+    rc = docListOfTerm(v, aTerm[i].iColumn, &aTerm[i], &right);
+    if( rc ){
+      queryClear(pQuery);
+      dataBufferDestroy(&left);
+      return rc;
     }
+    dataBufferInit(&new, 0);
+    docListExceptMerge(left.pData, left.nData, right.pData, right.nData, &new);
+    dataBufferDestroy(&right);
+    dataBufferDestroy(&left);
+    left = new;
   }
-  *r++ = '\0';
-  assert( r == result + len );
-  return result;
-}
-
-static int sql_exec(sqlite3 *db, const char *zDb, const char *zName,
-                    const char *zFormat){
-  char *zCommand = string_format(zFormat, zDb, zName);
-  int rc;
-  FTSTRACE(("FTS3 sql: %s\n", zCommand));
-  rc = sqlite3_exec(db, zCommand, NULL, 0, NULL);
-  sqlite3_free(zCommand);
-  return rc;
-}
 
-static int sql_prepare(sqlite3 *db, const char *zDb, const char *zName,
-                       sqlite3_stmt **ppStmt, const char *zFormat){
-  char *zCommand = string_format(zFormat, zDb, zName);
-  int rc;
-  FTSTRACE(("FTS3 prepare: %s\n", zCommand));
-  rc = sqlite3_prepare_v2(db, zCommand, -1, ppStmt, NULL);
-  sqlite3_free(zCommand);
+  *pResult = left;
   return rc;
 }
 
-/* end utility functions */
-
-/* Forward reference */
-typedef struct fulltext_vtab fulltext_vtab;
-
-/* A single term in a query is represented by an instances of
-** the following structure. Each word which may match against
-** document content is a term. Operators, like NEAR or OR, are
-** not terms. Query terms are organized as a flat list stored
-** in the Query.pTerms array.
-**
-** If the QueryTerm.nPhrase variable is non-zero, then the QueryTerm
-** is the first in a contiguous string of terms that are either part
-** of the same phrase, or connected by the NEAR operator.
-**
-** If the QueryTerm.nNear variable is non-zero, then the token is followed 
-** by a NEAR operator with span set to (nNear-1). For example, the 
-** following query:
-**
-** The QueryTerm.iPhrase variable stores the index of the token within
-** its phrase, indexed starting at 1, or 1 if the token is not part 
-** of any phrase.
-**
-** For example, the data structure used to represent the following query:
-**
-**     ... MATCH 'sqlite NEAR/5 google NEAR/2 "search engine"'
+/*
+** This is the xFilter interface for the virtual table.  See
+** the virtual table xFilter method documentation for additional
+** information.
 **
-** is:
+** If idxNum==QUERY_GENERIC then do a full table scan against
+** the %_content table.
 **
-**     {nPhrase=4, iPhrase=1, nNear=6, pTerm="sqlite"},
-**     {nPhrase=0, iPhrase=1, nNear=3, pTerm="google"},
-**     {nPhrase=0, iPhrase=1, nNear=0, pTerm="search"},
-**     {nPhrase=0, iPhrase=2, nNear=0, pTerm="engine"},
+** If idxNum==QUERY_DOCID then do a docid lookup for a single entry
+** in the %_content table.
 **
-** compiling the FTS3 syntax to Query structures is done by the parseQuery()
-** function.
+** If idxNum>=QUERY_FULLTEXT then use the full text index.  The
+** column on the left-hand side of the MATCH operator is column
+** number idxNum-QUERY_FULLTEXT, 0 indexed.  argv[0] is the right-hand
+** side of the MATCH operator.
 */
-typedef struct QueryTerm {
-  short int nPhrase; /* How many following terms are part of the same phrase */
-  short int iPhrase; /* This is the i-th term of a phrase. */
-  short int iColumn; /* Column of the index that must match this term */
-  signed char nNear; /* term followed by a NEAR operator with span=(nNear-1) */
-  signed char isOr;  /* this term is preceded by "OR" */
-  signed char isNot; /* this term is preceded by "-" */
-  signed char isPrefix; /* this term is followed by "*" */
-  char *pTerm;       /* text of the term.  '\000' terminated.  malloced */
-  int nTerm;         /* Number of bytes in pTerm[] */
-} QueryTerm;
-
-
-/* A query string is parsed into a Query structure.
- *
- * We could, in theory, allow query strings to be complicated
- * nested expressions with precedence determined by parentheses.
- * But none of the major search engines do this.  (Perhaps the
- * feeling is that an parenthesized expression is two complex of
- * an idea for the average user to grasp.)  Taking our lead from
- * the major search engines, we will allow queries to be a list
- * of terms (with an implied AND operator) or phrases in double-quotes,
- * with a single optional "-" before each non-phrase term to designate
- * negation and an optional OR connector.
- *
- * OR binds more tightly than the implied AND, which is what the
- * major search engines seem to do.  So, for example:
- * 
- *    [one two OR three]     ==>    one AND (two OR three)
- *    [one OR two three]     ==>    (one OR two) AND three
- *
- * A "-" before a term matches all entries that lack that term.
- * The "-" must occur immediately before the term with in intervening
- * space.  This is how the search engines do it.
- *
- * A NOT term cannot be the right-hand operand of an OR.  If this
- * occurs in the query string, the NOT is ignored:
- *
- *    [one OR -two]          ==>    one OR two
- *
- */
-typedef struct Query {
-  fulltext_vtab *pFts;  /* The full text index */
-  int nTerms;           /* Number of terms in the query */
-  QueryTerm *pTerms;    /* Array of terms.  Space obtained from malloc() */
-  int nextIsOr;         /* Set the isOr flag on the next inserted term */
-  int nextIsNear;       /* Set the isOr flag on the next inserted term */
-  int nextColumn;       /* Next word parsed must be in this column */
-  int dfltColumn;       /* The default column */
-} Query;
-
-
-/*
-** An instance of the following structure keeps track of generated
-** matching-word offset information and snippets.
+/* TODO(shess) Upgrade the cursor initialization and destruction to
+** account for fulltextFilter() being called multiple times on the
+** same cursor.  The current solution is very fragile.  Apply fix to
+** fts3 as appropriate.
 */
-typedef struct Snippet {
-  int nMatch;     /* Total number of matches */
-  int nAlloc;     /* Space allocated for aMatch[] */
-  struct snippetMatch { /* One entry for each matching term */
-    char snStatus;       /* Status flag for use while constructing snippets */
-    short int iCol;      /* The column that contains the match */
-    short int iTerm;     /* The index in Query.pTerms[] of the matching term */
-    int iToken;          /* The index of the matching document token */
-    short int nByte;     /* Number of bytes in the term */
-    int iStart;          /* The offset to the first character of the term */
-  } *aMatch;      /* Points to space obtained from malloc */
-  char *zOffset;  /* Text rendering of aMatch[] */
-  int nOffset;    /* strlen(zOffset) */
-  char *zSnippet; /* Snippet text */
-  int nSnippet;   /* strlen(zSnippet) */
-} Snippet;
+static int fulltextFilter(
+  sqlite3_vtab_cursor *pCursor,     /* The cursor used for this query */
+  int idxNum, const char *idxStr,   /* Which indexing scheme to use */
+  int argc, sqlite3_value **argv    /* Arguments for the indexing scheme */
+){
+  fulltext_cursor *c = (fulltext_cursor *) pCursor;
+  fulltext_vtab *v = cursor_vtab(c);
+  int rc;
 
+  FTSTRACE(("FTS3 Filter %p\n",pCursor));
 
-typedef enum QueryType {
-  QUERY_GENERIC,   /* table scan */
-  QUERY_DOCID,     /* lookup by docid */
-  QUERY_FULLTEXT   /* QUERY_FULLTEXT + [i] is a full-text search for column i*/
-} QueryType;
+  /* If the cursor has a statement that was not prepared according to
+  ** idxNum, clear it.  I believe all calls to fulltextFilter with a
+  ** given cursor will have the same idxNum , but in this case it's
+  ** easy to be safe.
+  */
+  if( c->pStmt && c->iCursorType!=idxNum ){
+    sqlite3_finalize(c->pStmt);
+    c->pStmt = NULL;
+  }
+
+  /* Get a fresh statement appropriate to idxNum. */
+  /* TODO(shess): Add a prepared-statement cache in the vt structure.
+  ** The cache must handle multiple open cursors.  Easier to cache the
+  ** statement variants at the vt to reduce malloc/realloc/free here.
+  ** Or we could have a StringBuffer variant which allowed stack
+  ** construction for small values.
+  */
+  if( !c->pStmt ){
+    StringBuffer sb;
+    initStringBuffer(&sb);
+    append(&sb, "SELECT docid, ");
+    appendList(&sb, v->nColumn, v->azContentColumn);
+    append(&sb, " FROM %_content");
+    if( idxNum!=QUERY_GENERIC ) append(&sb, " WHERE docid = ?");
+    rc = sql_prepare(v->db, v->zDb, v->zName, &c->pStmt,
+                     stringBufferData(&sb));
+    stringBufferDestroy(&sb);
+    if( rc!=SQLITE_OK ) return rc;
+    c->iCursorType = idxNum;
+  }else{
+    sqlite3_reset(c->pStmt);
+    assert( c->iCursorType==idxNum );
+  }
 
-typedef enum fulltext_statement {
-  CONTENT_INSERT_STMT,
-  CONTENT_SELECT_STMT,
-  CONTENT_UPDATE_STMT,
-  CONTENT_DELETE_STMT,
+  switch( idxNum ){
+    case QUERY_GENERIC:
+      break;
 
-  BLOCK_INSERT_STMT,
-  BLOCK_SELECT_STMT,
-  BLOCK_DELETE_STMT,
+    case QUERY_DOCID:
+      rc = sqlite3_bind_int64(c->pStmt, 1, sqlite3_value_int64(argv[0]));
+      if( rc!=SQLITE_OK ) return rc;
+      break;
 
-  SEGDIR_MAX_INDEX_STMT,
-  SEGDIR_SET_STMT,
-  SEGDIR_SELECT_STMT,
-  SEGDIR_SPAN_STMT,
-  SEGDIR_DELETE_STMT,
-  SEGDIR_SELECT_ALL_STMT,
+    default:   /* full-text search */
+    {
+      const char *zQuery = (const char *)sqlite3_value_text(argv[0]);
+      assert( idxNum<=QUERY_FULLTEXT+v->nColumn);
+      assert( argc==1 );
+      queryClear(&c->q);
+      if( c->result.nData!=0 ){
+        /* This case happens if the same cursor is used repeatedly. */
+        dlrDestroy(&c->reader);
+        dataBufferReset(&c->result);
+      }else{
+        dataBufferInit(&c->result, 0);
+      }
+      rc = fulltextQuery(v, idxNum-QUERY_FULLTEXT, zQuery, -1, &c->result, &c->q);
+      if( rc!=SQLITE_OK ) return rc;
+      if( c->result.nData!=0 ){
+        dlrInit(&c->reader, DL_DOCIDS, c->result.pData, c->result.nData);
+      }
+      break;
+    }
+  }
 
-  MAX_STMT                     /* Always at end! */
-} fulltext_statement;
+  return fulltextNext(pCursor);
+}
 
-/* These must exactly match the enum above. */
-/* TODO(shess): Is there some risk that a statement will be used in two
-** cursors at once, e.g.  if a query joins a virtual table to itself?
-** If so perhaps we should move some of these to the cursor object.
+/* This is the xEof method of the virtual table.  The SQLite core
+** calls this routine to find out if it has reached the end of
+** a query's results set.
 */
-static const char *const fulltext_zStatement[MAX_STMT] = {
-  /* CONTENT_INSERT */ NULL,  /* generated in contentInsertStatement() */
-  /* CONTENT_SELECT */ NULL,  /* generated in contentSelectStatement() */
-  /* CONTENT_UPDATE */ NULL,  /* generated in contentUpdateStatement() */
-  /* CONTENT_DELETE */ "delete from %_content where docid = ?",
-
-  /* BLOCK_INSERT */
-  "insert into %_segments (blockid, block) values (null, ?)",
-  /* BLOCK_SELECT */ "select block from %_segments where blockid = ?",
-  /* BLOCK_DELETE */ "delete from %_segments where blockid between ? and ?",
-
-  /* SEGDIR_MAX_INDEX */ "select max(idx) from %_segdir where level = ?",
-  /* SEGDIR_SET */ "insert into %_segdir values (?, ?, ?, ?, ?, ?)",
-  /* SEGDIR_SELECT */
-  "select start_block, leaves_end_block, root from %_segdir "
-  " where level = ? order by idx",
-  /* SEGDIR_SPAN */
-  "select min(start_block), max(end_block) from %_segdir "
-  " where level = ? and start_block <> 0",
-  /* SEGDIR_DELETE */ "delete from %_segdir where level = ?",
-  /* SEGDIR_SELECT_ALL */
-  "select root, leaves_end_block from %_segdir order by level desc, idx",
-};
+static int fulltextEof(sqlite3_vtab_cursor *pCursor){
+  fulltext_cursor *c = (fulltext_cursor *) pCursor;
+  return c->eof;
+}
 
-/*
-** A connection to a fulltext index is an instance of the following
-** structure.  The xCreate and xConnect methods create an instance
-** of this structure and xDestroy and xDisconnect free that instance.
-** All other methods receive a pointer to the structure as one of their
-** arguments.
+/* This is the xColumn method of the virtual table.  The SQLite
+** core calls this method during a query when it needs the value
+** of a column from the virtual table.  This method needs to use
+** one of the sqlite3_result_*() routines to store the requested
+** value back in the pContext.
 */
-struct fulltext_vtab {
-  sqlite3_vtab base;               /* Base class used by SQLite core */
-  sqlite3 *db;                     /* The database connection */
-  const char *zDb;                 /* logical database name */
-  const char *zName;               /* virtual table name */
-  int nColumn;                     /* number of columns in virtual table */
-  char **azColumn;                 /* column names.  malloced */
-  char **azContentColumn;          /* column names in content table; malloced */
-  sqlite3_tokenizer *pTokenizer;   /* tokenizer for inserts and queries */
-
-  /* Precompiled statements which we keep as long as the table is
-  ** open.
-  */
-  sqlite3_stmt *pFulltextStatements[MAX_STMT];
-
-  /* Precompiled statements used for segment merges.  We run a
-  ** separate select across the leaf level of each tree being merged.
-  */
-  sqlite3_stmt *pLeafSelectStmts[MERGE_COUNT];
-  /* The statement used to prepare pLeafSelectStmts. */
-#define LEAF_SELECT \
-  "select block from %_segments where blockid between ? and ? order by blockid"
+static int fulltextColumn(sqlite3_vtab_cursor *pCursor,
+                          sqlite3_context *pContext, int idxCol){
+  fulltext_cursor *c = (fulltext_cursor *) pCursor;
+  fulltext_vtab *v = cursor_vtab(c);
 
-  /* These buffer pending index updates during transactions.
-  ** nPendingData estimates the memory size of the pending data.  It
-  ** doesn't include the hash-bucket overhead, nor any malloc
-  ** overhead.  When nPendingData exceeds kPendingThreshold, the
-  ** buffer is flushed even before the transaction closes.
-  ** pendingTerms stores the data, and is only valid when nPendingData
-  ** is >=0 (nPendingData<0 means pendingTerms has not been
-  ** initialized).  iPrevDocid is the last docid written, used to make
-  ** certain we're inserting in sorted order.
-  */
-  int nPendingData;
-#define kPendingThreshold (1*1024*1024)
-  sqlite_int64 iPrevDocid;
-  fts3Hash pendingTerms;
-};
+  if( idxColnColumn ){
+    sqlite3_value *pVal = sqlite3_column_value(c->pStmt, idxCol+1);
+    sqlite3_result_value(pContext, pVal);
+  }else if( idxCol==v->nColumn ){
+    /* The extra column whose name is the same as the table.
+    ** Return a blob which is a pointer to the cursor
+    */
+    sqlite3_result_blob(pContext, &c, sizeof(c), SQLITE_TRANSIENT);
+  }else if( idxCol==v->nColumn+1 ){
+    /* The docid column, which is an alias for rowid. */
+    sqlite3_value *pVal = sqlite3_column_value(c->pStmt, 0);
+    sqlite3_result_value(pContext, pVal);
+  }
+  return SQLITE_OK;
+}
 
-/*
-** When the core wants to do a query, it create a cursor using a
-** call to xOpen.  This structure is an instance of a cursor.  It
-** is destroyed by xClose.
+/* This is the xRowid method.  The SQLite core calls this routine to
+** retrieve the rowid for the current row of the result set.  fts3
+** exposes %_content.docid as the rowid for the virtual table.  The
+** rowid should be written to *pRowid.
 */
-typedef struct fulltext_cursor {
-  sqlite3_vtab_cursor base;        /* Base class used by SQLite core */
-  QueryType iCursorType;           /* Copy of sqlite3_index_info.idxNum */
-  sqlite3_stmt *pStmt;             /* Prepared statement in use by the cursor */
-  int eof;                         /* True if at End Of Results */
-  Query q;                         /* Parsed query string */
-  Snippet snippet;                 /* Cached snippet for the current row */
-  int iColumn;                     /* Column being searched */
-  DataBuffer result;               /* Doclist results from fulltextQuery */
-  DLReader reader;                 /* Result reader if result not empty */
-} fulltext_cursor;
+static int fulltextRowid(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){
+  fulltext_cursor *c = (fulltext_cursor *) pCursor;
 
-static struct fulltext_vtab *cursor_vtab(fulltext_cursor *c){
-  return (fulltext_vtab *) c->base.pVtab;
+  *pRowid = sqlite3_column_int64(c->pStmt, 0);
+  return SQLITE_OK;
 }
 
-static const sqlite3_module fts3Module;   /* forward declaration */
+/* Add all terms in [zText] to pendingTerms table.  If [iColumn] > 0,
+** we also store positions and offsets in the hash table using that
+** column number.
+*/
+static int buildTerms(fulltext_vtab *v, sqlite_int64 iDocid,
+                      const char *zText, int iColumn){
+  sqlite3_tokenizer *pTokenizer = v->pTokenizer;
+  sqlite3_tokenizer_cursor *pCursor;
+  const char *pToken;
+  int nTokenBytes;
+  int iStartOffset, iEndOffset, iPosition;
+  int rc;
 
-/* Return a dynamically generated statement of the form
- *   insert into %_content (docid, ...) values (?, ...)
- */
-static const char *contentInsertStatement(fulltext_vtab *v){
-  StringBuffer sb;
-  int i;
+  rc = pTokenizer->pModule->xOpen(pTokenizer, zText, -1, &pCursor);
+  if( rc!=SQLITE_OK ) return rc;
 
-  initStringBuffer(&sb);
-  append(&sb, "insert into %_content (docid, ");
-  appendList(&sb, v->nColumn, v->azContentColumn);
-  append(&sb, ") values (?");
-  for(i=0; inColumn; ++i)
-    append(&sb, ", ?");
-  append(&sb, ")");
-  return stringBufferData(&sb);
-}
+  pCursor->pTokenizer = pTokenizer;
+  while( SQLITE_OK==(rc=pTokenizer->pModule->xNext(pCursor,
+                                                   &pToken, &nTokenBytes,
+                                                   &iStartOffset, &iEndOffset,
+                                                   &iPosition)) ){
+    DLCollector *p;
+    int nData;                   /* Size of doclist before our update. */
 
-/* Return a dynamically generated statement of the form
- *   select  from %_content where docid = ?
- */
-static const char *contentSelectStatement(fulltext_vtab *v){
-  StringBuffer sb;
-  initStringBuffer(&sb);
-  append(&sb, "SELECT ");
-  appendList(&sb, v->nColumn, v->azContentColumn);
-  append(&sb, " FROM %_content WHERE docid = ?");
-  return stringBufferData(&sb);
-}
+    /* Positions can't be negative; we use -1 as a terminator
+     * internally.  Token can't be NULL or empty. */
+    if( iPosition<0 || pToken == NULL || nTokenBytes == 0 ){
+      rc = SQLITE_ERROR;
+      break;
+    }
 
-/* Return a dynamically generated statement of the form
- *   update %_content set [col_0] = ?, [col_1] = ?, ...
- *                    where docid = ?
- */
-static const char *contentUpdateStatement(fulltext_vtab *v){
-  StringBuffer sb;
-  int i;
+    p = fts3HashFind(&v->pendingTerms, pToken, nTokenBytes);
+    if( p==NULL ){
+      nData = 0;
+      p = dlcNew(iDocid, DL_DEFAULT);
+      fts3HashInsert(&v->pendingTerms, pToken, nTokenBytes, p);
 
-  initStringBuffer(&sb);
-  append(&sb, "update %_content set ");
-  for(i=0; inColumn; ++i) {
-    if( i>0 ){
-      append(&sb, ", ");
+      /* Overhead for our hash table entry, the key, and the value. */
+      v->nPendingData += sizeof(struct fts3HashElem)+sizeof(*p)+nTokenBytes;
+    }else{
+      nData = p->b.nData;
+      if( p->dlw.iPrevDocid!=iDocid ) dlcNext(p, iDocid);
     }
-    append(&sb, v->azContentColumn[i]);
-    append(&sb, " = ?");
+    if( iColumn>=0 ){
+      dlcAddPos(p, iColumn, iPosition, iStartOffset, iEndOffset);
+    }
+
+    /* Accumulate data added by dlcNew or dlcNext, and dlcAddPos. */
+    v->nPendingData += p->b.nData-nData;
   }
-  append(&sb, " where docid = ?");
-  return stringBufferData(&sb);
-}
 
-/* Puts a freshly-prepared statement determined by iStmt in *ppStmt.
-** If the indicated statement has never been prepared, it is prepared
-** and cached, otherwise the cached version is reset.
-*/
-static int sql_get_statement(fulltext_vtab *v, fulltext_statement iStmt,
-                             sqlite3_stmt **ppStmt){
-  assert( iStmtpFulltextStatements[iStmt]==NULL ){
-    const char *zStmt;
-    int rc;
-    switch( iStmt ){
-      case CONTENT_INSERT_STMT:
-        zStmt = contentInsertStatement(v); break;
-      case CONTENT_SELECT_STMT:
-        zStmt = contentSelectStatement(v); break;
-      case CONTENT_UPDATE_STMT:
-        zStmt = contentUpdateStatement(v); break;
-      default:
-        zStmt = fulltext_zStatement[iStmt];
-    }
-    rc = sql_prepare(v->db, v->zDb, v->zName, &v->pFulltextStatements[iStmt],
-                         zStmt);
-    if( zStmt != fulltext_zStatement[iStmt]) sqlite3_free((void *) zStmt);
-    if( rc!=SQLITE_OK ) return rc;
-  } else {
-    int rc = sqlite3_reset(v->pFulltextStatements[iStmt]);
+  /* TODO(shess) Check return?  Should this be able to cause errors at
+  ** this point?  Actually, same question about sqlite3_finalize(),
+  ** though one could argue that failure there means that the data is
+  ** not durable.  *ponder*
+  */
+  pTokenizer->pModule->xClose(pCursor);
+  if( SQLITE_DONE == rc ) return SQLITE_OK;
+  return rc;
+}
+
+/* Add doclists for all terms in [pValues] to pendingTerms table. */
+static int insertTerms(fulltext_vtab *v, sqlite_int64 iDocid,
+                       sqlite3_value **pValues){
+  int i;
+  for(i = 0; i < v->nColumn ; ++i){
+    char *zText = (char*)sqlite3_value_text(pValues[i]);
+    int rc = buildTerms(v, iDocid, zText, i);
     if( rc!=SQLITE_OK ) return rc;
   }
-
-  *ppStmt = v->pFulltextStatements[iStmt];
   return SQLITE_OK;
 }
 
-/* Like sqlite3_step(), but convert SQLITE_DONE to SQLITE_OK and
-** SQLITE_ROW to SQLITE_ERROR.  Useful for statements like UPDATE,
-** where we expect no results.
+/* Add empty doclists for all terms in the given row's content to
+** pendingTerms.
 */
-static int sql_single_step(sqlite3_stmt *s){
-  int rc = sqlite3_step(s);
-  return (rc==SQLITE_DONE) ? SQLITE_OK : rc;
-}
+static int deleteTerms(fulltext_vtab *v, sqlite_int64 iDocid){
+  const char **pValues;
+  int i, rc;
 
-/* Like sql_get_statement(), but for special replicated LEAF_SELECT
-** statements.
-*/
-/* TODO(shess) Write version for generic statements and then share
-** that between the cached-statement functions.
-*/
-static int sql_get_leaf_statement(fulltext_vtab *v, int idx,
-                                  sqlite3_stmt **ppStmt){
-  assert( idx>=0 && idxpLeafSelectStmts[idx]==NULL ){
-    int rc = sql_prepare(v->db, v->zDb, v->zName, &v->pLeafSelectStmts[idx],
-                         LEAF_SELECT);
-    if( rc!=SQLITE_OK ) return rc;
-  }else{
-    int rc = sqlite3_reset(v->pLeafSelectStmts[idx]);
-    if( rc!=SQLITE_OK ) return rc;
+  /* TODO(shess) Should we allow such tables at all? */
+  if( DL_DEFAULT==DL_DOCIDS ) return SQLITE_ERROR;
+
+  rc = content_select(v, iDocid, &pValues);
+  if( rc!=SQLITE_OK ) return rc;
+
+  for(i = 0 ; i < v->nColumn; ++i) {
+    rc = buildTerms(v, iDocid, pValues[i], -1);
+    if( rc!=SQLITE_OK ) break;
   }
 
-  *ppStmt = v->pLeafSelectStmts[idx];
+  freeStringArray(v->nColumn, pValues);
   return SQLITE_OK;
 }
 
-/* insert into %_content (docid, ...) values ([docid], [pValues])
-** If the docid contains SQL NULL, then a unique docid will be
-** generated.
+/* TODO(shess) Refactor the code to remove this forward decl. */
+static int initPendingTerms(fulltext_vtab *v, sqlite_int64 iDocid);
+
+/* Insert a row into the %_content table; set *piDocid to be the ID of the
+** new row.  Add doclists for terms to pendingTerms.
 */
-static int content_insert(fulltext_vtab *v, sqlite3_value *docid,
-                          sqlite3_value **pValues){
-  sqlite3_stmt *s;
-  int i;
-  int rc = sql_get_statement(v, CONTENT_INSERT_STMT, &s);
+static int index_insert(fulltext_vtab *v, sqlite3_value *pRequestDocid,
+                        sqlite3_value **pValues, sqlite_int64 *piDocid){
+  int rc;
+
+  rc = content_insert(v, pRequestDocid, pValues);  /* execute an SQL INSERT */
   if( rc!=SQLITE_OK ) return rc;
 
-  rc = sqlite3_bind_value(s, 1, docid);
+  /* docid column is an alias for rowid. */
+  *piDocid = sqlite3_last_insert_rowid(v->db);
+  rc = initPendingTerms(v, *piDocid);
   if( rc!=SQLITE_OK ) return rc;
 
-  for(i=0; inColumn; ++i){
-    rc = sqlite3_bind_value(s, 2+i, pValues[i]);
-    if( rc!=SQLITE_OK ) return rc;
-  }
+  return insertTerms(v, *piDocid, pValues);
+}
 
-  return sql_single_step(s);
+/* Delete a row from the %_content table; add empty doclists for terms
+** to pendingTerms.
+*/
+static int index_delete(fulltext_vtab *v, sqlite_int64 iRow){
+  int rc = initPendingTerms(v, iRow);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = deleteTerms(v, iRow);
+  if( rc!=SQLITE_OK ) return rc;
+
+  return content_delete(v, iRow);  /* execute an SQL DELETE */
 }
 
-/* update %_content set col0 = pValues[0], col1 = pValues[1], ...
- *                  where docid = [iDocid] */
-static int content_update(fulltext_vtab *v, sqlite3_value **pValues,
-                          sqlite_int64 iDocid){
-  sqlite3_stmt *s;
-  int i;
-  int rc = sql_get_statement(v, CONTENT_UPDATE_STMT, &s);
+/* Update a row in the %_content table; add delete doclists to
+** pendingTerms for old terms not in the new data, add insert doclists
+** to pendingTerms for terms in the new data.
+*/
+static int index_update(fulltext_vtab *v, sqlite_int64 iRow,
+                        sqlite3_value **pValues){
+  int rc = initPendingTerms(v, iRow);
   if( rc!=SQLITE_OK ) return rc;
 
-  for(i=0; inColumn; ++i){
-    rc = sqlite3_bind_value(s, 1+i, pValues[i]);
-    if( rc!=SQLITE_OK ) return rc;
-  }
+  /* Generate an empty doclist for each term that previously appeared in this
+   * row. */
+  rc = deleteTerms(v, iRow);
+  if( rc!=SQLITE_OK ) return rc;
 
-  rc = sqlite3_bind_int64(s, 1+v->nColumn, iDocid);
+  rc = content_update(v, pValues, iRow);  /* execute an SQL UPDATE */
   if( rc!=SQLITE_OK ) return rc;
 
-  return sql_single_step(s);
+  /* Now add positions for terms which appear in the updated row. */
+  return insertTerms(v, iRow, pValues);
 }
 
-static void freeStringArray(int nString, const char **pString){
-  int i;
+/*******************************************************************/
+/* InteriorWriter is used to collect terms and block references into
+** interior nodes in %_segments.  See commentary at top of file for
+** format.
+*/
 
-  for (i=0 ; i < nString ; ++i) {
-    if( pString[i]!=NULL ) sqlite3_free((void *) pString[i]);
+/* How large interior nodes can grow. */
+#define INTERIOR_MAX 2048
+
+/* Minimum number of terms per interior node (except the root). This
+** prevents large terms from making the tree too skinny - must be >0
+** so that the tree always makes progress.  Note that the min tree
+** fanout will be INTERIOR_MIN_TERMS+1.
+*/
+#define INTERIOR_MIN_TERMS 7
+#if INTERIOR_MIN_TERMS<1
+# error INTERIOR_MIN_TERMS must be greater than 0.
+#endif
+
+/* ROOT_MAX controls how much data is stored inline in the segment
+** directory.
+*/
+/* TODO(shess) Push ROOT_MAX down to whoever is writing things.  It's
+** only here so that interiorWriterRootInfo() and leafWriterRootInfo()
+** can both see it, but if the caller passed it in, we wouldn't even
+** need a define.
+*/
+#define ROOT_MAX 1024
+#if ROOT_MAXterm, 0);
+    dataBufferReplace(&block->term, pTerm, nTerm);
+
+    n = fts3PutVarint(c, iHeight);
+    n += fts3PutVarint(c+n, iChildBlock);
+    dataBufferInit(&block->data, INTERIOR_MAX);
+    dataBufferReplace(&block->data, c, n);
   }
-  sqlite3_free((void *) pString);
+  return block;
 }
 
-/* select * from %_content where docid = [iDocid]
- * The caller must delete the returned array and all strings in it.
- * null fields will be NULL in the returned array.
- *
- * TODO: Perhaps we should return pointer/length strings here for consistency
- * with other code which uses pointer/length. */
-static int content_select(fulltext_vtab *v, sqlite_int64 iDocid,
-                          const char ***pValues){
-  sqlite3_stmt *s;
-  const char **values;
-  int i;
-  int rc;
+#ifndef NDEBUG
+/* Verify that the data is readable as an interior node. */
+static void interiorBlockValidate(InteriorBlock *pBlock){
+  const char *pData = pBlock->data.pData;
+  int nData = pBlock->data.nData;
+  int n, iDummy;
+  sqlite_int64 iBlockid;
 
-  *pValues = NULL;
+  assert( nData>0 );
+  assert( pData!=0 );
+  assert( pData+nData>pData );
 
-  rc = sql_get_statement(v, CONTENT_SELECT_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+  /* Must lead with height of node as a varint(n), n>0 */
+  n = fts3GetVarint32(pData, &iDummy);
+  assert( n>0 );
+  assert( iDummy>0 );
+  assert( n0 );
+  assert( n<=nData );
+  pData += n;
+  nData -= n;
 
-  rc = sqlite3_step(s);
-  if( rc!=SQLITE_ROW ) return rc;
+  /* Zero or more terms of positive length */
+  if( nData!=0 ){
+    /* First term is not delta-encoded. */
+    n = fts3GetVarint32(pData, &iDummy);
+    assert( n>0 );
+    assert( iDummy>0 );
+    assert( n+iDummy>0);
+    assert( n+iDummy<=nData );
+    pData += n+iDummy;
+    nData -= n+iDummy;
 
-  values = (const char **) sqlite3_malloc(v->nColumn * sizeof(const char *));
-  for(i=0; inColumn; ++i){
-    if( sqlite3_column_type(s, i)==SQLITE_NULL ){
-      values[i] = NULL;
-    }else{
-      values[i] = string_dup((char*)sqlite3_column_text(s, i));
+    /* Following terms delta-encoded. */
+    while( nData!=0 ){
+      /* Length of shared prefix. */
+      n = fts3GetVarint32(pData, &iDummy);
+      assert( n>0 );
+      assert( iDummy>=0 );
+      assert( n0 );
+      assert( iDummy>0 );
+      assert( n+iDummy>0);
+      assert( n+iDummy<=nData );
+      pData += n+iDummy;
+      nData -= n+iDummy;
     }
   }
+}
+#define ASSERT_VALID_INTERIOR_BLOCK(x) interiorBlockValidate(x)
+#else
+#define ASSERT_VALID_INTERIOR_BLOCK(x) assert( 1 )
+#endif
 
-  /* We expect only one row.  We must execute another sqlite3_step()
-   * to complete the iteration; otherwise the table will remain locked. */
-  rc = sqlite3_step(s);
-  if( rc==SQLITE_DONE ){
-    *pValues = values;
-    return SQLITE_OK;
-  }
+typedef struct InteriorWriter {
+  int iHeight;                   /* from 0 at leaves. */
+  InteriorBlock *first, *last;
+  struct InteriorWriter *parentWriter;
 
-  freeStringArray(v->nColumn, values);
-  return rc;
+  DataBuffer term;               /* Last term written to block "last". */
+  sqlite_int64 iOpeningChildBlock; /* First child block in block "last". */
+#ifndef NDEBUG
+  sqlite_int64 iLastChildBlock;  /* for consistency checks. */
+#endif
+} InteriorWriter;
+
+/* Initialize an interior node where pTerm[nTerm] marks the leftmost
+** term in the tree.  iChildBlock is the leftmost child block at the
+** next level down the tree.
+*/
+static void interiorWriterInit(int iHeight, const char *pTerm, int nTerm,
+                               sqlite_int64 iChildBlock,
+                               InteriorWriter *pWriter){
+  InteriorBlock *block;
+  assert( iHeight>0 );
+  CLEAR(pWriter);
+
+  pWriter->iHeight = iHeight;
+  pWriter->iOpeningChildBlock = iChildBlock;
+#ifndef NDEBUG
+  pWriter->iLastChildBlock = iChildBlock;
+#endif
+  block = interiorBlockNew(iHeight, iChildBlock, pTerm, nTerm);
+  pWriter->last = pWriter->first = block;
+  ASSERT_VALID_INTERIOR_BLOCK(pWriter->last);
+  dataBufferInit(&pWriter->term, 0);
 }
 
-/* delete from %_content where docid = [iDocid ] */
-static int content_delete(fulltext_vtab *v, sqlite_int64 iDocid){
-  sqlite3_stmt *s;
-  int rc = sql_get_statement(v, CONTENT_DELETE_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+/* Append the child node rooted at iChildBlock to the interior node,
+** with pTerm[nTerm] as the leftmost term in iChildBlock's subtree.
+*/
+static void interiorWriterAppend(InteriorWriter *pWriter,
+                                 const char *pTerm, int nTerm,
+                                 sqlite_int64 iChildBlock){
+  char c[VARINT_MAX+VARINT_MAX];
+  int n, nPrefix = 0;
 
-  rc = sqlite3_bind_int64(s, 1, iDocid);
-  if( rc!=SQLITE_OK ) return rc;
+  ASSERT_VALID_INTERIOR_BLOCK(pWriter->last);
 
-  return sql_single_step(s);
+  /* The first term written into an interior node is actually
+  ** associated with the second child added (the first child was added
+  ** in interiorWriterInit, or in the if clause at the bottom of this
+  ** function).  That term gets encoded straight up, with nPrefix left
+  ** at 0.
+  */
+  if( pWriter->term.nData==0 ){
+    n = fts3PutVarint(c, nTerm);
+  }else{
+    while( nPrefixterm.nData &&
+           pTerm[nPrefix]==pWriter->term.pData[nPrefix] ){
+      nPrefix++;
+    }
+
+    n = fts3PutVarint(c, nPrefix);
+    n += fts3PutVarint(c+n, nTerm-nPrefix);
+  }
+
+#ifndef NDEBUG
+  pWriter->iLastChildBlock++;
+#endif
+  assert( pWriter->iLastChildBlock==iChildBlock );
+
+  /* Overflow to a new block if the new term makes the current block
+  ** too big, and the current block already has enough terms.
+  */
+  if( pWriter->last->data.nData+n+nTerm-nPrefix>INTERIOR_MAX &&
+      iChildBlock-pWriter->iOpeningChildBlock>INTERIOR_MIN_TERMS ){
+    pWriter->last->next = interiorBlockNew(pWriter->iHeight, iChildBlock,
+                                           pTerm, nTerm);
+    pWriter->last = pWriter->last->next;
+    pWriter->iOpeningChildBlock = iChildBlock;
+    dataBufferReset(&pWriter->term);
+  }else{
+    dataBufferAppend2(&pWriter->last->data, c, n,
+                      pTerm+nPrefix, nTerm-nPrefix);
+    dataBufferReplace(&pWriter->term, pTerm, nTerm);
+  }
+  ASSERT_VALID_INTERIOR_BLOCK(pWriter->last);
 }
 
-/* insert into %_segments values ([pData])
-**   returns assigned blockid in *piBlockid
+/* Free the space used by pWriter, including the linked-list of
+** InteriorBlocks, and parentWriter, if present.
 */
-static int block_insert(fulltext_vtab *v, const char *pData, int nData,
-                        sqlite_int64 *piBlockid){
-  sqlite3_stmt *s;
-  int rc = sql_get_statement(v, BLOCK_INSERT_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+static int interiorWriterDestroy(InteriorWriter *pWriter){
+  InteriorBlock *block = pWriter->first;
 
-  rc = sqlite3_bind_blob(s, 1, pData, nData, SQLITE_STATIC);
+  while( block!=NULL ){
+    InteriorBlock *b = block;
+    block = block->next;
+    dataBufferDestroy(&b->term);
+    dataBufferDestroy(&b->data);
+    sqlite3_free(b);
+  }
+  if( pWriter->parentWriter!=NULL ){
+    interiorWriterDestroy(pWriter->parentWriter);
+    sqlite3_free(pWriter->parentWriter);
+  }
+  dataBufferDestroy(&pWriter->term);
+  SCRAMBLE(pWriter);
+  return SQLITE_OK;
+}
+
+/* If pWriter can fit entirely in ROOT_MAX, return it as the root info
+** directly, leaving *piEndBlockid unchanged.  Otherwise, flush
+** pWriter to %_segments, building a new layer of interior nodes, and
+** recursively ask for their root into.
+*/
+static int interiorWriterRootInfo(fulltext_vtab *v, InteriorWriter *pWriter,
+                                  char **ppRootInfo, int *pnRootInfo,
+                                  sqlite_int64 *piEndBlockid){
+  InteriorBlock *block = pWriter->first;
+  sqlite_int64 iBlockid = 0;
+  int rc;
+
+  /* If we can fit the segment inline */
+  if( block==pWriter->last && block->data.nDatadata.pData;
+    *pnRootInfo = block->data.nData;
+    return SQLITE_OK;
+  }
+
+  /* Flush the first block to %_segments, and create a new level of
+  ** interior node.
+  */
+  ASSERT_VALID_INTERIOR_BLOCK(block);
+  rc = block_insert(v, block->data.pData, block->data.nData, &iBlockid);
   if( rc!=SQLITE_OK ) return rc;
+  *piEndBlockid = iBlockid;
 
-  rc = sqlite3_step(s);
-  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
-  if( rc!=SQLITE_DONE ) return rc;
+  pWriter->parentWriter = sqlite3_malloc(sizeof(*pWriter->parentWriter));
+  interiorWriterInit(pWriter->iHeight+1,
+                     block->term.pData, block->term.nData,
+                     iBlockid, pWriter->parentWriter);
 
-  /* blockid column is an alias for rowid. */
-  *piBlockid = sqlite3_last_insert_rowid(v->db);
-  return SQLITE_OK;
+  /* Flush additional blocks and append to the higher interior
+  ** node.
+  */
+  for(block=block->next; block!=NULL; block=block->next){
+    ASSERT_VALID_INTERIOR_BLOCK(block);
+    rc = block_insert(v, block->data.pData, block->data.nData, &iBlockid);
+    if( rc!=SQLITE_OK ) return rc;
+    *piEndBlockid = iBlockid;
+
+    interiorWriterAppend(pWriter->parentWriter,
+                         block->term.pData, block->term.nData, iBlockid);
+  }
+
+  /* Parent node gets the chance to be the root. */
+  return interiorWriterRootInfo(v, pWriter->parentWriter,
+                                ppRootInfo, pnRootInfo, piEndBlockid);
 }
 
-/* delete from %_segments
-**   where blockid between [iStartBlockid] and [iEndBlockid]
-**
-** Deletes the range of blocks, inclusive, used to delete the blocks
-** which form a segment.
+/****************************************************************/
+/* InteriorReader is used to read off the data from an interior node
+** (see comment at top of file for the format).
 */
-static int block_delete(fulltext_vtab *v,
-                        sqlite_int64 iStartBlockid, sqlite_int64 iEndBlockid){
-  sqlite3_stmt *s;
-  int rc = sql_get_statement(v, BLOCK_DELETE_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+typedef struct InteriorReader {
+  const char *pData;
+  int nData;
 
-  rc = sqlite3_bind_int64(s, 1, iStartBlockid);
-  if( rc!=SQLITE_OK ) return rc;
+  DataBuffer term;          /* previous term, for decoding term delta. */
 
-  rc = sqlite3_bind_int64(s, 2, iEndBlockid);
-  if( rc!=SQLITE_OK ) return rc;
+  sqlite_int64 iBlockid;
+} InteriorReader;
 
-  return sql_single_step(s);
+static void interiorReaderDestroy(InteriorReader *pReader){
+  dataBufferDestroy(&pReader->term);
+  SCRAMBLE(pReader);
 }
 
-/* Returns SQLITE_ROW with *pidx set to the maximum segment idx found
-** at iLevel.  Returns SQLITE_DONE if there are no segments at
-** iLevel.  Otherwise returns an error.
+/* TODO(shess) The assertions are great, but what if we're in NDEBUG
+** and the blob is empty or otherwise contains suspect data?
 */
-static int segdir_max_index(fulltext_vtab *v, int iLevel, int *pidx){
-  sqlite3_stmt *s;
-  int rc = sql_get_statement(v, SEGDIR_MAX_INDEX_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+static void interiorReaderInit(const char *pData, int nData,
+                               InteriorReader *pReader){
+  int n, nTerm;
 
-  rc = sqlite3_bind_int(s, 1, iLevel);
-  if( rc!=SQLITE_OK ) return rc;
+  /* Require at least the leading flag byte */
+  assert( nData>0 );
+  assert( pData[0]!='\0' );
 
-  rc = sqlite3_step(s);
-  /* Should always get at least one row due to how max() works. */
-  if( rc==SQLITE_DONE ) return SQLITE_DONE;
-  if( rc!=SQLITE_ROW ) return rc;
+  CLEAR(pReader);
 
-  /* NULL means that there were no inputs to max(). */
-  if( SQLITE_NULL==sqlite3_column_type(s, 0) ){
-    rc = sqlite3_step(s);
-    if( rc==SQLITE_ROW ) return SQLITE_ERROR;
-    return rc;
+  /* Decode the base blockid, and set the cursor to the first term. */
+  n = fts3GetVarint(pData+1, &pReader->iBlockid);
+  assert( 1+n<=nData );
+  pReader->pData = pData+1+n;
+  pReader->nData = nData-(1+n);
+
+  /* A single-child interior node (such as when a leaf node was too
+  ** large for the segment directory) won't have any terms.
+  ** Otherwise, decode the first term.
+  */
+  if( pReader->nData==0 ){
+    dataBufferInit(&pReader->term, 0);
+  }else{
+    n = fts3GetVarint32(pReader->pData, &nTerm);
+    dataBufferInit(&pReader->term, nTerm);
+    dataBufferReplace(&pReader->term, pReader->pData+n, nTerm);
+    assert( n+nTerm<=pReader->nData );
+    pReader->pData += n+nTerm;
+    pReader->nData -= n+nTerm;
   }
-
-  *pidx = sqlite3_column_int(s, 0);
-
-  /* We expect only one row.  We must execute another sqlite3_step()
-   * to complete the iteration; otherwise the table will remain locked. */
-  rc = sqlite3_step(s);
-  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
-  if( rc!=SQLITE_DONE ) return rc;
-  return SQLITE_ROW;
 }
 
-/* insert into %_segdir values (
-**   [iLevel], [idx],
-**   [iStartBlockid], [iLeavesEndBlockid], [iEndBlockid],
-**   [pRootData]
-** )
-*/
-static int segdir_set(fulltext_vtab *v, int iLevel, int idx,
-                      sqlite_int64 iStartBlockid,
-                      sqlite_int64 iLeavesEndBlockid,
-                      sqlite_int64 iEndBlockid,
-                      const char *pRootData, int nRootData){
-  sqlite3_stmt *s;
-  int rc = sql_get_statement(v, SEGDIR_SET_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+static int interiorReaderAtEnd(InteriorReader *pReader){
+  return pReader->term.nData==0;
+}
 
-  rc = sqlite3_bind_int(s, 1, iLevel);
-  if( rc!=SQLITE_OK ) return rc;
+static sqlite_int64 interiorReaderCurrentBlockid(InteriorReader *pReader){
+  return pReader->iBlockid;
+}
 
-  rc = sqlite3_bind_int(s, 2, idx);
-  if( rc!=SQLITE_OK ) return rc;
+static int interiorReaderTermBytes(InteriorReader *pReader){
+  assert( !interiorReaderAtEnd(pReader) );
+  return pReader->term.nData;
+}
+static const char *interiorReaderTerm(InteriorReader *pReader){
+  assert( !interiorReaderAtEnd(pReader) );
+  return pReader->term.pData;
+}
 
-  rc = sqlite3_bind_int64(s, 3, iStartBlockid);
-  if( rc!=SQLITE_OK ) return rc;
+/* Step forward to the next term in the node. */
+static void interiorReaderStep(InteriorReader *pReader){
+  assert( !interiorReaderAtEnd(pReader) );
 
-  rc = sqlite3_bind_int64(s, 4, iLeavesEndBlockid);
-  if( rc!=SQLITE_OK ) return rc;
+  /* If the last term has been read, signal eof, else construct the
+  ** next term.
+  */
+  if( pReader->nData==0 ){
+    dataBufferReset(&pReader->term);
+  }else{
+    int n, nPrefix, nSuffix;
 
-  rc = sqlite3_bind_int64(s, 5, iEndBlockid);
-  if( rc!=SQLITE_OK ) return rc;
+    n = fts3GetVarint32(pReader->pData, &nPrefix);
+    n += fts3GetVarint32(pReader->pData+n, &nSuffix);
 
-  rc = sqlite3_bind_blob(s, 6, pRootData, nRootData, SQLITE_STATIC);
-  if( rc!=SQLITE_OK ) return rc;
+    /* Truncate the current term and append suffix data. */
+    pReader->term.nData = nPrefix;
+    dataBufferAppend(&pReader->term, pReader->pData+n, nSuffix);
 
-  return sql_single_step(s);
+    assert( n+nSuffix<=pReader->nData );
+    pReader->pData += n+nSuffix;
+    pReader->nData -= n+nSuffix;
+  }
+  pReader->iBlockid++;
 }
 
-/* Queries %_segdir for the block span of the segments in level
-** iLevel.  Returns SQLITE_DONE if there are no blocks for iLevel,
-** SQLITE_ROW if there are blocks, else an error.
+/* Compare the current term to pTerm[nTerm], returning strcmp-style
+** results.  If isPrefix, equality means equal through nTerm bytes.
 */
-static int segdir_span(fulltext_vtab *v, int iLevel,
-                       sqlite_int64 *piStartBlockid,
-                       sqlite_int64 *piEndBlockid){
-  sqlite3_stmt *s;
-  int rc = sql_get_statement(v, SEGDIR_SPAN_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
-
-  rc = sqlite3_bind_int(s, 1, iLevel);
-  if( rc!=SQLITE_OK ) return rc;
-
-  rc = sqlite3_step(s);
-  if( rc==SQLITE_DONE ) return SQLITE_DONE;  /* Should never happen */
-  if( rc!=SQLITE_ROW ) return rc;
+static int interiorReaderTermCmp(InteriorReader *pReader,
+                                 const char *pTerm, int nTerm, int isPrefix){
+  const char *pReaderTerm = interiorReaderTerm(pReader);
+  int nReaderTerm = interiorReaderTermBytes(pReader);
+  int c, n = nReaderTerm0 ) return -1;
+    if( nTerm>0 ) return 1;
+    return 0;
   }
 
-  *piStartBlockid = sqlite3_column_int64(s, 0);
-  *piEndBlockid = sqlite3_column_int64(s, 1);
-
-  /* We expect only one row.  We must execute another sqlite3_step()
-   * to complete the iteration; otherwise the table will remain locked. */
-  rc = sqlite3_step(s);
-  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
-  if( rc!=SQLITE_DONE ) return rc;
-  return SQLITE_ROW;
+  c = memcmp(pReaderTerm, pTerm, n);
+  if( c!=0 ) return c;
+  if( isPrefix && n==nTerm ) return 0;
+  return nReaderTerm - nTerm;
 }
 
-/* Delete the segment blocks and segment directory records for all
-** segments at iLevel.
+/****************************************************************/
+/* LeafWriter is used to collect terms and associated doclist data
+** into leaf blocks in %_segments (see top of file for format info).
+** Expected usage is:
+**
+** LeafWriter writer;
+** leafWriterInit(0, 0, &writer);
+** while( sorted_terms_left_to_process ){
+**   // data is doclist data for that term.
+**   rc = leafWriterStep(v, &writer, pTerm, nTerm, pData, nData);
+**   if( rc!=SQLITE_OK ) goto err;
+** }
+** rc = leafWriterFinalize(v, &writer);
+**err:
+** leafWriterDestroy(&writer);
+** return rc;
+**
+** leafWriterStep() may write a collected leaf out to %_segments.
+** leafWriterFinalize() finishes writing any buffered data and stores
+** a root node in %_segdir.  leafWriterDestroy() frees all buffers and
+** InteriorWriters allocated as part of writing this segment.
+**
+** TODO(shess) Document leafWriterStepMerge().
 */
-static int segdir_delete(fulltext_vtab *v, int iLevel){
-  sqlite3_stmt *s;
-  sqlite_int64 iStartBlockid, iEndBlockid;
-  int rc = segdir_span(v, iLevel, &iStartBlockid, &iEndBlockid);
-  if( rc!=SQLITE_ROW && rc!=SQLITE_DONE ) return rc;
 
-  if( rc==SQLITE_ROW ){
-    rc = block_delete(v, iStartBlockid, iEndBlockid);
-    if( rc!=SQLITE_OK ) return rc;
-  }
+/* Put terms with data this big in their own block. */
+#define STANDALONE_MIN 1024
 
-  /* Delete the segment directory itself. */
-  rc = sql_get_statement(v, SEGDIR_DELETE_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+/* Keep leaf blocks below this size. */
+#define LEAF_MAX 2048
 
-  rc = sqlite3_bind_int64(s, 1, iLevel);
-  if( rc!=SQLITE_OK ) return rc;
+typedef struct LeafWriter {
+  int iLevel;
+  int idx;
+  sqlite_int64 iStartBlockid;     /* needed to create the root info */
+  sqlite_int64 iEndBlockid;       /* when we're done writing. */
 
-  return sql_single_step(s);
-}
+  DataBuffer term;                /* previous encoded term */
+  DataBuffer data;                /* encoding buffer */
 
-/* TODO(shess) clearPendingTerms() is far down the file because
-** writeZeroSegment() is far down the file because LeafWriter is far
-** down the file.  Consider refactoring the code to move the non-vtab
-** code above the vtab code so that we don't need this forward
-** reference.
-*/
-static int clearPendingTerms(fulltext_vtab *v);
+  /* bytes of first term in the current node which distinguishes that
+  ** term from the last term of the previous node.
+  */
+  int nTermDistinct;
 
-/*
-** Free the memory used to contain a fulltext_vtab structure.
-*/
-static void fulltext_vtab_destroy(fulltext_vtab *v){
-  int iStmt, i;
+  InteriorWriter parentWriter;    /* if we overflow */
+  int has_parent;
+} LeafWriter;
 
-  FTSTRACE(("FTS3 Destroy %p\n", v));
-  for( iStmt=0; iStmtpFulltextStatements[iStmt]!=NULL ){
-      sqlite3_finalize(v->pFulltextStatements[iStmt]);
-      v->pFulltextStatements[iStmt] = NULL;
-    }
-  }
+static void leafWriterInit(int iLevel, int idx, LeafWriter *pWriter){
+  CLEAR(pWriter);
+  pWriter->iLevel = iLevel;
+  pWriter->idx = idx;
 
-  for( i=0; ipLeafSelectStmts[i]!=NULL ){
-      sqlite3_finalize(v->pLeafSelectStmts[i]);
-      v->pLeafSelectStmts[i] = NULL;
-    }
-  }
+  dataBufferInit(&pWriter->term, 32);
 
-  if( v->pTokenizer!=NULL ){
-    v->pTokenizer->pModule->xDestroy(v->pTokenizer);
-    v->pTokenizer = NULL;
-  }
+  /* Start out with a reasonably sized block, though it can grow. */
+  dataBufferInit(&pWriter->data, LEAF_MAX);
+}
 
-  clearPendingTerms(v);
+#ifndef NDEBUG
+/* Verify that the data is readable as a leaf node. */
+static void leafNodeValidate(const char *pData, int nData){
+  int n, iDummy;
 
-  sqlite3_free(v->azColumn);
-  for(i = 0; i < v->nColumn; ++i) {
-    sqlite3_free(v->azContentColumn[i]);
-  }
-  sqlite3_free(v->azContentColumn);
-  sqlite3_free(v);
-}
+  if( nData==0 ) return;
+  assert( nData>0 );
+  assert( pData!=0 );
+  assert( pData+nData>pData );
 
-/*
-** Token types for parsing the arguments to xConnect or xCreate.
-*/
-#define TOKEN_EOF         0    /* End of file */
-#define TOKEN_SPACE       1    /* Any kind of whitespace */
-#define TOKEN_ID          2    /* An identifier */
-#define TOKEN_STRING      3    /* A string literal */
-#define TOKEN_PUNCT       4    /* A single punctuation character */
+  /* Must lead with a varint(0) */
+  n = fts3GetVarint32(pData, &iDummy);
+  assert( iDummy==0 );
+  assert( n>0 );
+  assert( n0x1f && isFtsIdChar[c-0x20]))
+  /* Leading term length and data must fit in buffer. */
+  n = fts3GetVarint32(pData, &iDummy);
+  assert( n>0 );
+  assert( iDummy>0 );
+  assert( n+iDummy>0 );
+  assert( n+iDummy0 );
+  assert( iDummy>0 );
+  assert( n+iDummy>0 );
+  assert( n+iDummy<=nData );
+  ASSERT_VALID_DOCLIST(DL_DEFAULT, pData+n, iDummy, NULL);
+  pData += n+iDummy;
+  nData -= n+iDummy;
 
-/*
-** Return the length of the token that begins at z[0]. 
-** Store the token type in *tokenType before returning.
-*/
-static int ftsGetToken(const char *z, int *tokenType){
-  int i, c;
-  switch( *z ){
-    case 0: {
-      *tokenType = TOKEN_EOF;
-      return 0;
-    }
-    case ' ': case '\t': case '\n': case '\f': case '\r': {
-      for(i=1; safe_isspace(z[i]); i++){}
-      *tokenType = TOKEN_SPACE;
-      return i;
-    }
-    case '`':
-    case '\'':
-    case '"': {
-      int delim = z[0];
-      for(i=1; (c=z[i])!=0; i++){
-        if( c==delim ){
-          if( z[i+1]==delim ){
-            i++;
-          }else{
-            break;
-          }
-        }
-      }
-      *tokenType = TOKEN_STRING;
-      return i + (c!=0);
-    }
-    case '[': {
-      for(i=1, c=z[0]; c!=']' && (c=z[i])!=0; i++){}
-      *tokenType = TOKEN_ID;
-      return i;
-    }
-    default: {
-      if( !ftsIdChar(*z) ){
-        break;
-      }
-      for(i=1; ftsIdChar(z[i]); i++){}
-      *tokenType = TOKEN_ID;
-      return i;
-    }
+  /* Verify that trailing terms and doclists also are readable. */
+  while( nData!=0 ){
+    n = fts3GetVarint32(pData, &iDummy);
+    assert( n>0 );
+    assert( iDummy>=0 );
+    assert( n0 );
+    assert( iDummy>0 );
+    assert( n+iDummy>0 );
+    assert( n+iDummy0 );
+    assert( iDummy>0 );
+    assert( n+iDummy>0 );
+    assert( n+iDummy<=nData );
+    ASSERT_VALID_DOCLIST(DL_DEFAULT, pData+n, iDummy, NULL);
+    pData += n+iDummy;
+    nData -= n+iDummy;
   }
-  *tokenType = TOKEN_PUNCT;
-  return 1;
 }
+#define ASSERT_VALID_LEAF_NODE(p, n) leafNodeValidate(p, n)
+#else
+#define ASSERT_VALID_LEAF_NODE(p, n) assert( 1 )
+#endif
 
-/*
-** A token extracted from a string is an instance of the following
-** structure.
+/* Flush the current leaf node to %_segments, and adding the resulting
+** blockid and the starting term to the interior node which will
+** contain it.
 */
-typedef struct FtsToken {
-  const char *z;       /* Pointer to token text.  Not '\000' terminated */
-  short int n;         /* Length of the token text in bytes. */
-} FtsToken;
+static int leafWriterInternalFlush(fulltext_vtab *v, LeafWriter *pWriter,
+                                   int iData, int nData){
+  sqlite_int64 iBlockid = 0;
+  const char *pStartingTerm;
+  int nStartingTerm, rc, n;
 
-/*
-** Given a input string (which is really one of the argv[] parameters
-** passed into xConnect or xCreate) split the string up into tokens.
-** Return an array of pointers to '\000' terminated strings, one string
-** for each non-whitespace token.
-**
-** The returned array is terminated by a single NULL pointer.
-**
-** Space to hold the returned array is obtained from a single
-** malloc and should be freed by passing the return value to free().
-** The individual strings within the token list are all a part of
-** the single memory allocation and will all be freed at once.
-*/
-static char **tokenizeString(const char *z, int *pnToken){
-  int nToken = 0;
-  FtsToken *aToken = sqlite3_malloc( strlen(z) * sizeof(aToken[0]) );
-  int n = 1;
-  int e, i;
-  int totalSize = 0;
-  char **azToken;
-  char *zCopy;
-  while( n>0 ){
-    n = ftsGetToken(z, &e);
-    if( e!=TOKEN_SPACE ){
-      aToken[nToken].z = z;
-      aToken[nToken].n = n;
-      nToken++;
-      totalSize += n+1;
-    }
-    z += n;
-  }
-  azToken = (char**)sqlite3_malloc( nToken*sizeof(char*) + totalSize );
-  zCopy = (char*)&azToken[nToken];
-  nToken--;
-  for(i=0; i2 );
+  assert( iData>=0 );
+  assert( iData+nData<=pWriter->data.nData );
+  ASSERT_VALID_LEAF_NODE(pWriter->data.pData+iData, nData);
 
-/*
-** Convert an SQL-style quoted string into a normal string by removing
-** the quote characters.  The conversion is done in-place.  If the
-** input does not begin with a quote character, then this routine
-** is a no-op.
-**
-** Examples:
-**
-**     "abc"   becomes   abc
-**     'xyz'   becomes   xyz
-**     [pqr]   becomes   pqr
-**     `mno`   becomes   mno
-*/
-static void dequoteString(char *z){
-  int quote;
-  int i, j;
-  if( z==0 ) return;
-  quote = z[0];
-  switch( quote ){
-    case '\'':  break;
-    case '"':   break;
-    case '`':   break;                /* For MySQL compatibility */
-    case '[':   quote = ']';  break;  /* For MS SqlServer compatibility */
-    default:    return;
-  }
-  for(i=1, j=0; z[i]; i++){
-    if( z[i]==quote ){
-      if( z[i+1]==quote ){
-        z[j++] = quote;
-        i++;
-      }else{
-        z[j++] = 0;
-        break;
-      }
-    }else{
-      z[j++] = z[i];
-    }
-  }
-}
+  rc = block_insert(v, pWriter->data.pData+iData, nData, &iBlockid);
+  if( rc!=SQLITE_OK ) return rc;
+  assert( iBlockid!=0 );
 
-/*
-** The input azIn is a NULL-terminated list of tokens.  Remove the first
-** token and all punctuation tokens.  Remove the quotes from
-** around string literal tokens.
-**
-** Example:
-**
-**     input:      tokenize chinese ( 'simplifed' , 'mixed' )
-**     output:     chinese simplifed mixed
-**
-** Another example:
-**
-**     input:      delimiters ( '[' , ']' , '...' )
-**     output:     [ ] ...
-*/
-static void tokenListToIdList(char **azIn){
-  int i, j;
-  if( azIn ){
-    for(i=0, j=-1; azIn[i]; i++){
-      if( safe_isalnum(azIn[i][0]) || azIn[i][1] ){
-        dequoteString(azIn[i]);
-        if( j>=0 ){
-          azIn[j] = azIn[i];
-        }
-        j++;
-      }
-    }
-    azIn[j] = 0;
+  /* Reconstruct the first term in the leaf for purposes of building
+  ** the interior node.
+  */
+  n = fts3GetVarint32(pWriter->data.pData+iData+1, &nStartingTerm);
+  pStartingTerm = pWriter->data.pData+iData+1+n;
+  assert( pWriter->data.nData>iData+1+n+nStartingTerm );
+  assert( pWriter->nTermDistinct>0 );
+  assert( pWriter->nTermDistinct<=nStartingTerm );
+  nStartingTerm = pWriter->nTermDistinct;
+
+  if( pWriter->has_parent ){
+    interiorWriterAppend(&pWriter->parentWriter,
+                         pStartingTerm, nStartingTerm, iBlockid);
+  }else{
+    interiorWriterInit(1, pStartingTerm, nStartingTerm, iBlockid,
+                       &pWriter->parentWriter);
+    pWriter->has_parent = 1;
+  }
+
+  /* Track the span of this segment's leaf nodes. */
+  if( pWriter->iEndBlockid==0 ){
+    pWriter->iEndBlockid = pWriter->iStartBlockid = iBlockid;
+  }else{
+    pWriter->iEndBlockid++;
+    assert( iBlockid==pWriter->iEndBlockid );
   }
+
+  return SQLITE_OK;
 }
+static int leafWriterFlush(fulltext_vtab *v, LeafWriter *pWriter){
+  int rc = leafWriterInternalFlush(v, pWriter, 0, pWriter->data.nData);
+  if( rc!=SQLITE_OK ) return rc;
 
+  /* Re-initialize the output buffer. */
+  dataBufferReset(&pWriter->data);
 
-/*
-** Find the first alphanumeric token in the string zIn.  Null-terminate
-** this token.  Remove any quotation marks.  And return a pointer to
-** the result.
-*/
-static char *firstToken(char *zIn, char **pzTail){
-  int n, ttype;
-  while(1){
-    n = ftsGetToken(zIn, &ttype);
-    if( ttype==TOKEN_SPACE ){
-      zIn += n;
-    }else if( ttype==TOKEN_EOF ){
-      *pzTail = zIn;
-      return 0;
-    }else{
-      zIn[n] = 0;
-      *pzTail = &zIn[1];
-      dequoteString(zIn);
-      return zIn;
-    }
-  }
-  /*NOTREACHED*/
+  return SQLITE_OK;
 }
 
-/* Return true if...
-**
-**   *  s begins with the string t, ignoring case
-**   *  s is longer than t
-**   *  The first character of s beyond t is not a alphanumeric
-** 
-** Ignore leading space in *s.
-**
-** To put it another way, return true if the first token of
-** s[] is t[].
+/* Fetch the root info for the segment.  If the entire leaf fits
+** within ROOT_MAX, then it will be returned directly, otherwise it
+** will be flushed and the root info will be returned from the
+** interior node.  *piEndBlockid is set to the blockid of the last
+** interior or leaf node written to disk (0 if none are written at
+** all).
 */
-static int startsWith(const char *s, const char *t){
-  while( safe_isspace(*s) ){ s++; }
-  while( *t ){
-    if( safe_tolower(*s++)!=safe_tolower(*t++) ) return 0;
+static int leafWriterRootInfo(fulltext_vtab *v, LeafWriter *pWriter,
+                              char **ppRootInfo, int *pnRootInfo,
+                              sqlite_int64 *piEndBlockid){
+  /* we can fit the segment entirely inline */
+  if( !pWriter->has_parent && pWriter->data.nDatadata.pData;
+    *pnRootInfo = pWriter->data.nData;
+    *piEndBlockid = 0;
+    return SQLITE_OK;
   }
-  return *s!='_' && !safe_isalnum(*s);
+
+  /* Flush remaining leaf data. */
+  if( pWriter->data.nData>0 ){
+    int rc = leafWriterFlush(v, pWriter);
+    if( rc!=SQLITE_OK ) return rc;
+  }
+
+  /* We must have flushed a leaf at some point. */
+  assert( pWriter->has_parent );
+
+  /* Tenatively set the end leaf blockid as the end blockid.  If the
+  ** interior node can be returned inline, this will be the final
+  ** blockid, otherwise it will be overwritten by
+  ** interiorWriterRootInfo().
+  */
+  *piEndBlockid = pWriter->iEndBlockid;
+
+  return interiorWriterRootInfo(v, &pWriter->parentWriter,
+                                ppRootInfo, pnRootInfo, piEndBlockid);
 }
 
-/*
-** An instance of this structure defines the "spec" of a
-** full text index.  This structure is populated by parseSpec
-** and use by fulltextConnect and fulltextCreate.
+/* Collect the rootInfo data and store it into the segment directory.
+** This has the effect of flushing the segment's leaf data to
+** %_segments, and also flushing any interior nodes to %_segments.
 */
-typedef struct TableSpec {
-  const char *zDb;         /* Logical database name */
-  const char *zName;       /* Name of the full-text index */
-  int nColumn;             /* Number of columns to be indexed */
-  char **azColumn;         /* Original names of columns to be indexed */
-  char **azContentColumn;  /* Column names for %_content */
-  char **azTokenizer;      /* Name of tokenizer and its arguments */
-} TableSpec;
+static int leafWriterFinalize(fulltext_vtab *v, LeafWriter *pWriter){
+  sqlite_int64 iEndBlockid;
+  char *pRootInfo;
+  int rc, nRootInfo;
 
-/*
-** Reclaim all of the memory used by a TableSpec
-*/
-static void clearTableSpec(TableSpec *p) {
-  sqlite3_free(p->azColumn);
-  sqlite3_free(p->azContentColumn);
-  sqlite3_free(p->azTokenizer);
+  rc = leafWriterRootInfo(v, pWriter, &pRootInfo, &nRootInfo, &iEndBlockid);
+  if( rc!=SQLITE_OK ) return rc;
+
+  /* Don't bother storing an entirely empty segment. */
+  if( iEndBlockid==0 && nRootInfo==0 ) return SQLITE_OK;
+
+  return segdir_set(v, pWriter->iLevel, pWriter->idx,
+                    pWriter->iStartBlockid, pWriter->iEndBlockid,
+                    iEndBlockid, pRootInfo, nRootInfo);
 }
 
-/* Parse a CREATE VIRTUAL TABLE statement, which looks like this:
- *
- * CREATE VIRTUAL TABLE email
- *        USING fts3(subject, body, tokenize mytokenizer(myarg))
- *
- * We return parsed information in a TableSpec structure.
- * 
- */
-static int parseSpec(TableSpec *pSpec, int argc, const char *const*argv,
-                     char**pzErr){
-  int i, n;
-  char *z, *zDummy;
-  char **azArg;
-  const char *zTokenizer = 0;    /* argv[] entry describing the tokenizer */
+static void leafWriterDestroy(LeafWriter *pWriter){
+  if( pWriter->has_parent ) interiorWriterDestroy(&pWriter->parentWriter);
+  dataBufferDestroy(&pWriter->term);
+  dataBufferDestroy(&pWriter->data);
+}
 
-  assert( argc>=3 );
-  /* Current interface:
-  ** argv[0] - module name
-  ** argv[1] - database name
-  ** argv[2] - table name
-  ** argv[3..] - columns, optionally followed by tokenizer specification
-  **             and snippet delimiters specification.
-  */
+/* Encode a term into the leafWriter, delta-encoding as appropriate.
+** Returns the length of the new term which distinguishes it from the
+** previous term, which can be used to set nTermDistinct when a node
+** boundary is crossed.
+*/
+static int leafWriterEncodeTerm(LeafWriter *pWriter,
+                                const char *pTerm, int nTerm){
+  char c[VARINT_MAX+VARINT_MAX];
+  int n, nPrefix = 0;
 
-  /* Make a copy of the complete argv[][] array in a single allocation.
-  ** The argv[][] array is read-only and transient.  We can write to the
-  ** copy in order to modify things and the copy is persistent.
-  */
-  CLEAR(pSpec);
-  for(i=n=0; i0 );
+  while( nPrefixterm.nData &&
+         pTerm[nPrefix]==pWriter->term.pData[nPrefix] ){
+    nPrefix++;
+    /* Failing this implies that the terms weren't in order. */
+    assert( nPrefixzDb = azArg[1];
-  pSpec->zName = azArg[2];
-  pSpec->nColumn = 0;
-  pSpec->azColumn = azArg;
-  zTokenizer = "tokenize simple";
-  for(i=3; inColumn] = firstToken(azArg[i], &zDummy);
-      pSpec->nColumn++;
-    }
-  }
-  if( pSpec->nColumn==0 ){
-    azArg[0] = "content";
-    pSpec->nColumn = 1;
+  if( pWriter->data.nData==0 ){
+    /* Encode the node header and leading term as:
+    **  varint(0)
+    **  varint(nTerm)
+    **  char pTerm[nTerm]
+    */
+    n = fts3PutVarint(c, '\0');
+    n += fts3PutVarint(c+n, nTerm);
+    dataBufferAppend2(&pWriter->data, c, n, pTerm, nTerm);
+  }else{
+    /* Delta-encode the term as:
+    **  varint(nPrefix)
+    **  varint(nSuffix)
+    **  char pTermSuffix[nSuffix]
+    */
+    n = fts3PutVarint(c, nPrefix);
+    n += fts3PutVarint(c+n, nTerm-nPrefix);
+    dataBufferAppend2(&pWriter->data, c, n, pTerm+nPrefix, nTerm-nPrefix);
   }
+  dataBufferReplace(&pWriter->term, pTerm, nTerm);
 
-  /*
-  ** Construct the list of content column names.
-  **
-  ** Each content column name will be of the form cNNAAAA
-  ** where NN is the column number and AAAA is the sanitized
-  ** column name.  "sanitized" means that special characters are
-  ** converted to "_".  The cNN prefix guarantees that all column
-  ** names are unique.
-  **
-  ** The AAAA suffix is not strictly necessary.  It is included
-  ** for the convenience of people who might examine the generated
-  ** %_content table and wonder what the columns are used for.
-  */
-  pSpec->azContentColumn = sqlite3_malloc( pSpec->nColumn * sizeof(char *) );
-  if( pSpec->azContentColumn==0 ){
-    clearTableSpec(pSpec);
-    return SQLITE_NOMEM;
-  }
-  for(i=0; inColumn; i++){
-    char *p;
-    pSpec->azContentColumn[i] = sqlite3_mprintf("c%d%s", i, azArg[i]);
-    for (p = pSpec->azContentColumn[i]; *p ; ++p) {
-      if( !safe_isalnum(*p) ) *p = '_';
-    }
-  }
+  return nPrefix+1;
+}
 
-  /*
-  ** Parse the tokenizer specification string.
+/* Used to avoid a memmove when a large amount of doclist data is in
+** the buffer.  This constructs a node and term header before
+** iDoclistData and flushes the resulting complete node using
+** leafWriterInternalFlush().
+*/
+static int leafWriterInlineFlush(fulltext_vtab *v, LeafWriter *pWriter,
+                                 const char *pTerm, int nTerm,
+                                 int iDoclistData){
+  char c[VARINT_MAX+VARINT_MAX];
+  int iData, n = fts3PutVarint(c, 0);
+  n += fts3PutVarint(c+n, nTerm);
+
+  /* There should always be room for the header.  Even if pTerm shared
+  ** a substantial prefix with the previous term, the entire prefix
+  ** could be constructed from earlier data in the doclist, so there
+  ** should be room.
   */
-  pSpec->azTokenizer = tokenizeString(zTokenizer, &n);
-  tokenListToIdList(pSpec->azTokenizer);
+  assert( iDoclistData>=n+nTerm );
 
-  return SQLITE_OK;
-}
+  iData = iDoclistData-(n+nTerm);
+  memcpy(pWriter->data.pData+iData, c, n);
+  memcpy(pWriter->data.pData+iData+n, pTerm, nTerm);
 
-/*
-** Generate a CREATE TABLE statement that describes the schema of
-** the virtual table.  Return a pointer to this schema string.
-**
-** Space is obtained from sqlite3_mprintf() and should be freed
-** using sqlite3_free().
-*/
-static char *fulltextSchema(
-  int nColumn,                  /* Number of columns */
-  const char *const* azColumn,  /* List of columns */
-  const char *zTableName        /* Name of the table */
-){
-  int i;
-  char *zSchema, *zNext;
-  const char *zSep = "(";
-  zSchema = sqlite3_mprintf("CREATE TABLE x");
-  for(i=0; idata.nData-iData);
 }
 
-/*
-** Build a new sqlite3_vtab structure that will describe the
-** fulltext index defined by spec.
+/* Push pTerm[nTerm] along with the doclist data to the leaf layer of
+** %_segments.
 */
-static int constructVtab(
-  sqlite3 *db,              /* The SQLite database connection */
-  fts3Hash *pHash,          /* Hash table containing tokenizers */
-  TableSpec *spec,          /* Parsed spec information from parseSpec() */
-  sqlite3_vtab **ppVTab,    /* Write the resulting vtab structure here */
-  char **pzErr              /* Write any error message here */
-){
-  int rc;
-  int n;
-  fulltext_vtab *v = 0;
-  const sqlite3_tokenizer_module *m = NULL;
-  char *schema;
-
-  char const *zTok;         /* Name of tokenizer to use for this fts table */
-  int nTok;                 /* Length of zTok, including nul terminator */
+static int leafWriterStepMerge(fulltext_vtab *v, LeafWriter *pWriter,
+                               const char *pTerm, int nTerm,
+                               DLReader *pReaders, int nReaders){
+  char c[VARINT_MAX+VARINT_MAX];
+  int iTermData = pWriter->data.nData, iDoclistData;
+  int i, nData, n, nActualData, nActual, rc, nTermDistinct;
 
-  v = (fulltext_vtab *) sqlite3_malloc(sizeof(fulltext_vtab));
-  if( v==0 ) return SQLITE_NOMEM;
-  CLEAR(v);
-  /* sqlite will initialize v->base */
-  v->db = db;
-  v->zDb = spec->zDb;       /* Freed when azColumn is freed */
-  v->zName = spec->zName;   /* Freed when azColumn is freed */
-  v->nColumn = spec->nColumn;
-  v->azContentColumn = spec->azContentColumn;
-  spec->azContentColumn = 0;
-  v->azColumn = spec->azColumn;
-  spec->azColumn = 0;
+  ASSERT_VALID_LEAF_NODE(pWriter->data.pData, pWriter->data.nData);
+  nTermDistinct = leafWriterEncodeTerm(pWriter, pTerm, nTerm);
 
-  if( spec->azTokenizer==0 ){
-    return SQLITE_NOMEM;
-  }
+  /* Remember nTermDistinct if opening a new node. */
+  if( iTermData==0 ) pWriter->nTermDistinct = nTermDistinct;
 
-  zTok = spec->azTokenizer[0]; 
-  if( !zTok ){
-    zTok = "simple";
-  }
-  nTok = strlen(zTok)+1;
+  iDoclistData = pWriter->data.nData;
 
-  m = (sqlite3_tokenizer_module *)sqlite3Fts3HashFind(pHash, zTok, nTok);
-  if( !m ){
-    *pzErr = sqlite3_mprintf("unknown tokenizer: %s", spec->azTokenizer[0]);
-    rc = SQLITE_ERROR;
-    goto err;
+  /* Estimate the length of the merged doclist so we can leave space
+  ** to encode it.
+  */
+  for(i=0, nData=0; idata, c, n);
 
-  for(n=0; spec->azTokenizer[n]; n++){}
-  if( n ){
-    rc = m->xCreate(n-1, (const char*const*)&spec->azTokenizer[1],
-                    &v->pTokenizer);
-  }else{
-    rc = m->xCreate(0, 0, &v->pTokenizer);
-  }
-  if( rc!=SQLITE_OK ) goto err;
-  v->pTokenizer->pModule = m;
+  docListMerge(&pWriter->data, pReaders, nReaders);
+  ASSERT_VALID_DOCLIST(DL_DEFAULT,
+                       pWriter->data.pData+iDoclistData+n,
+                       pWriter->data.nData-iDoclistData-n, NULL);
 
-  /* TODO: verify the existence of backing tables foo_content, foo_term */
+  /* The actual amount of doclist data at this point could be smaller
+  ** than the length we encoded.  Additionally, the space required to
+  ** encode this length could be smaller.  For small doclists, this is
+  ** not a big deal, we can just use memmove() to adjust things.
+  */
+  nActualData = pWriter->data.nData-(iDoclistData+n);
+  nActual = fts3PutVarint(c, nActualData);
+  assert( nActualData<=nData );
+  assert( nActual<=n );
 
-  schema = fulltextSchema(v->nColumn, (const char*const*)v->azColumn,
-                          spec->zName);
-  rc = sqlite3_declare_vtab(db, schema);
-  sqlite3_free(schema);
-  if( rc!=SQLITE_OK ) goto err;
+  /* If the new doclist is big enough for force a standalone leaf
+  ** node, we can immediately flush it inline without doing the
+  ** memmove().
+  */
+  /* TODO(shess) This test matches leafWriterStep(), which does this
+  ** test before it knows the cost to varint-encode the term and
+  ** doclist lengths.  At some point, change to
+  ** pWriter->data.nData-iTermData>STANDALONE_MIN.
+  */
+  if( nTerm+nActualData>STANDALONE_MIN ){
+    /* Push leaf node from before this term. */
+    if( iTermData>0 ){
+      rc = leafWriterInternalFlush(v, pWriter, 0, iTermData);
+      if( rc!=SQLITE_OK ) return rc;
 
-  memset(v->pFulltextStatements, 0, sizeof(v->pFulltextStatements));
+      pWriter->nTermDistinct = nTermDistinct;
+    }
 
-  /* Indicate that the buffer is not live. */
-  v->nPendingData = -1;
+    /* Fix the encoded doclist length. */
+    iDoclistData += n - nActual;
+    memcpy(pWriter->data.pData+iDoclistData, c, nActual);
 
-  *ppVTab = &v->base;
-  FTSTRACE(("FTS3 Connect %p\n", v));
+    /* Push the standalone leaf node. */
+    rc = leafWriterInlineFlush(v, pWriter, pTerm, nTerm, iDoclistData);
+    if( rc!=SQLITE_OK ) return rc;
 
-  return rc;
+    /* Leave the node empty. */
+    dataBufferReset(&pWriter->data);
 
-err:
-  fulltext_vtab_destroy(v);
-  return rc;
-}
+    return rc;
+  }
 
-static int fulltextConnect(
-  sqlite3 *db,
-  void *pAux,
-  int argc, const char *const*argv,
-  sqlite3_vtab **ppVTab,
-  char **pzErr
-){
-  TableSpec spec;
-  int rc = parseSpec(&spec, argc, argv, pzErr);
-  if( rc!=SQLITE_OK ) return rc;
+  /* At this point, we know that the doclist was small, so do the
+  ** memmove if indicated.
+  */
+  if( nActualdata.pData+iDoclistData+nActual,
+            pWriter->data.pData+iDoclistData+n,
+            pWriter->data.nData-(iDoclistData+n));
+    pWriter->data.nData -= n-nActual;
+  }
 
-  rc = constructVtab(db, (fts3Hash *)pAux, &spec, ppVTab, pzErr);
-  clearTableSpec(&spec);
-  return rc;
-}
+  /* Replace written length with actual length. */
+  memcpy(pWriter->data.pData+iDoclistData, c, nActual);
 
-/* The %_content table holds the text of each document, with
-** the docid column exposed as the SQLite rowid for the table.
-*/
-/* TODO(shess) This comment needs elaboration to match the updated
-** code.  Work it into the top-of-file comment at that time.
-*/
-static int fulltextCreate(sqlite3 *db, void *pAux,
-                          int argc, const char * const *argv,
-                          sqlite3_vtab **ppVTab, char **pzErr){
-  int rc;
-  TableSpec spec;
-  StringBuffer schema;
-  FTSTRACE(("FTS3 Create\n"));
+  /* If the node is too large, break things up. */
+  /* TODO(shess) This test matches leafWriterStep(), which does this
+  ** test before it knows the cost to varint-encode the term and
+  ** doclist lengths.  At some point, change to
+  ** pWriter->data.nData>LEAF_MAX.
+  */
+  if( iTermData+nTerm+nActualData>LEAF_MAX ){
+    /* Flush out the leading data as a node */
+    rc = leafWriterInternalFlush(v, pWriter, 0, iTermData);
+    if( rc!=SQLITE_OK ) return rc;
 
-  rc = parseSpec(&spec, argc, argv, pzErr);
-  if( rc!=SQLITE_OK ) return rc;
+    pWriter->nTermDistinct = nTermDistinct;
 
-  initStringBuffer(&schema);
-  append(&schema, "CREATE TABLE %_content(");
-  append(&schema, "  docid INTEGER PRIMARY KEY,");
-  appendList(&schema, spec.nColumn, spec.azContentColumn);
-  append(&schema, ")");
-  rc = sql_exec(db, spec.zDb, spec.zName, stringBufferData(&schema));
-  stringBufferDestroy(&schema);
-  if( rc!=SQLITE_OK ) goto out;
+    /* Rebuild header using the current term */
+    n = fts3PutVarint(pWriter->data.pData, 0);
+    n += fts3PutVarint(pWriter->data.pData+n, nTerm);
+    memcpy(pWriter->data.pData+n, pTerm, nTerm);
+    n += nTerm;
 
-  rc = sql_exec(db, spec.zDb, spec.zName,
-                "create table %_segments("
-                "  blockid INTEGER PRIMARY KEY,"
-                "  block blob"
-                ");"
-                );
-  if( rc!=SQLITE_OK ) goto out;
+    /* There should always be room, because the previous encoding
+    ** included all data necessary to construct the term.
+    */
+    assert( ndata.nData-iDoclistDatadata.pData+n,
+           pWriter->data.pData+iDoclistData,
+           pWriter->data.nData-iDoclistData);
+    pWriter->data.nData -= iDoclistData-n;
+  }
+  ASSERT_VALID_LEAF_NODE(pWriter->data.pData, pWriter->data.nData);
 
-  rc = sql_exec(db, spec.zDb, spec.zName,
-                "create table %_segdir("
-                "  level integer,"
-                "  idx integer,"
-                "  start_block integer,"
-                "  leaves_end_block integer,"
-                "  end_block integer,"
-                "  root blob,"
-                "  primary key(level, idx)"
-                ");");
-  if( rc!=SQLITE_OK ) goto out;
+  return SQLITE_OK;
+}
 
-  rc = constructVtab(db, (fts3Hash *)pAux, &spec, ppVTab, pzErr);
+/* Push pTerm[nTerm] along with the doclist data to the leaf layer of
+** %_segments.
+*/
+/* TODO(shess) Revise writeZeroSegment() so that doclists are
+** constructed directly in pWriter->data.
+*/
+static int leafWriterStep(fulltext_vtab *v, LeafWriter *pWriter,
+                          const char *pTerm, int nTerm,
+                          const char *pData, int nData){
+  int rc;
+  DLReader reader;
+
+  dlrInit(&reader, DL_DEFAULT, pData, nData);
+  rc = leafWriterStepMerge(v, pWriter, pTerm, nTerm, &reader, 1);
+  dlrDestroy(&reader);
 
-out:
-  clearTableSpec(&spec);
   return rc;
 }
 
-/* Decide how to handle an SQL query. */
-static int fulltextBestIndex(sqlite3_vtab *pVTab, sqlite3_index_info *pInfo){
-  fulltext_vtab *v = (fulltext_vtab *)pVTab;
-  int i;
-  FTSTRACE(("FTS3 BestIndex\n"));
 
-  for(i=0; inConstraint; ++i){
-    const struct sqlite3_index_constraint *pConstraint;
-    pConstraint = &pInfo->aConstraint[i];
-    if( pConstraint->usable ) {
-      if( (pConstraint->iColumn==-1 || pConstraint->iColumn==v->nColumn+1) &&
-          pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ ){
-        pInfo->idxNum = QUERY_DOCID;      /* lookup by docid */
-        FTSTRACE(("FTS3 QUERY_DOCID\n"));
-      } else if( pConstraint->iColumn>=0 && pConstraint->iColumn<=v->nColumn &&
-                 pConstraint->op==SQLITE_INDEX_CONSTRAINT_MATCH ){
-        /* full-text search */
-        pInfo->idxNum = QUERY_FULLTEXT + pConstraint->iColumn;
-        FTSTRACE(("FTS3 QUERY_FULLTEXT %d\n", pConstraint->iColumn));
-      } else continue;
+/****************************************************************/
+/* LeafReader is used to iterate over an individual leaf node. */
+typedef struct LeafReader {
+  DataBuffer term;          /* copy of current term. */
 
-      pInfo->aConstraintUsage[i].argvIndex = 1;
-      pInfo->aConstraintUsage[i].omit = 1;
+  const char *pData;        /* data for current term. */
+  int nData;
+} LeafReader;
 
-      /* An arbitrary value for now.
-       * TODO: Perhaps docid matches should be considered cheaper than
-       * full-text searches. */
-      pInfo->estimatedCost = 1.0;   
+static void leafReaderDestroy(LeafReader *pReader){
+  dataBufferDestroy(&pReader->term);
+  SCRAMBLE(pReader);
+}
 
-      return SQLITE_OK;
-    }
-  }
-  pInfo->idxNum = QUERY_GENERIC;
-  return SQLITE_OK;
+static int leafReaderAtEnd(LeafReader *pReader){
+  return pReader->nData<=0;
 }
 
-static int fulltextDisconnect(sqlite3_vtab *pVTab){
-  FTSTRACE(("FTS3 Disconnect %p\n", pVTab));
-  fulltext_vtab_destroy((fulltext_vtab *)pVTab);
-  return SQLITE_OK;
+/* Access the current term. */
+static int leafReaderTermBytes(LeafReader *pReader){
+  return pReader->term.nData;
+}
+static const char *leafReaderTerm(LeafReader *pReader){
+  assert( pReader->term.nData>0 );
+  return pReader->term.pData;
 }
 
-static int fulltextDestroy(sqlite3_vtab *pVTab){
-  fulltext_vtab *v = (fulltext_vtab *)pVTab;
-  int rc;
+/* Access the doclist data for the current term. */
+static int leafReaderDataBytes(LeafReader *pReader){
+  int nData;
+  assert( pReader->term.nData>0 );
+  fts3GetVarint32(pReader->pData, &nData);
+  return nData;
+}
+static const char *leafReaderData(LeafReader *pReader){
+  int n, nData;
+  assert( pReader->term.nData>0 );
+  n = fts3GetVarint32(pReader->pData, &nData);
+  return pReader->pData+n;
+}
 
-  FTSTRACE(("FTS3 Destroy %p\n", pVTab));
-  rc = sql_exec(v->db, v->zDb, v->zName,
-                "drop table if exists %_content;"
-                "drop table if exists %_segments;"
-                "drop table if exists %_segdir;"
-                );
-  if( rc!=SQLITE_OK ) return rc;
+static void leafReaderInit(const char *pData, int nData,
+                           LeafReader *pReader){
+  int nTerm, n;
 
-  fulltext_vtab_destroy((fulltext_vtab *)pVTab);
-  return SQLITE_OK;
-}
+  assert( nData>0 );
+  assert( pData[0]=='\0' );
 
-static int fulltextOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
-  fulltext_cursor *c;
+  CLEAR(pReader);
 
-  c = (fulltext_cursor *) sqlite3_malloc(sizeof(fulltext_cursor));
-  if( c ){
-    memset(c, 0, sizeof(fulltext_cursor));
-    /* sqlite will initialize c->base */
-    *ppCursor = &c->base;
-    FTSTRACE(("FTS3 Open %p: %p\n", pVTab, c));
-    return SQLITE_OK;
-  }else{
-    return SQLITE_NOMEM;
-  }
+  /* Read the first term, skipping the header byte. */
+  n = fts3GetVarint32(pData+1, &nTerm);
+  dataBufferInit(&pReader->term, nTerm);
+  dataBufferReplace(&pReader->term, pData+1+n, nTerm);
+
+  /* Position after the first term. */
+  assert( 1+n+nTermpData = pData+1+n+nTerm;
+  pReader->nData = nData-1-n-nTerm;
 }
 
+/* Step the reader forward to the next term. */
+static void leafReaderStep(LeafReader *pReader){
+  int n, nData, nPrefix, nSuffix;
+  assert( !leafReaderAtEnd(pReader) );
+
+  /* Skip previous entry's data block. */
+  n = fts3GetVarint32(pReader->pData, &nData);
+  assert( n+nData<=pReader->nData );
+  pReader->pData += n+nData;
+  pReader->nData -= n+nData;
 
-/* Free all of the dynamically allocated memory held by *q
-*/
-static void queryClear(Query *q){
-  int i;
-  for(i = 0; i < q->nTerms; ++i){
-    sqlite3_free(q->pTerms[i].pTerm);
+  if( !leafReaderAtEnd(pReader) ){
+    /* Construct the new term using a prefix from the old term plus a
+    ** suffix from the leaf data.
+    */
+    n = fts3GetVarint32(pReader->pData, &nPrefix);
+    n += fts3GetVarint32(pReader->pData+n, &nSuffix);
+    assert( n+nSuffixnData );
+    pReader->term.nData = nPrefix;
+    dataBufferAppend(&pReader->term, pReader->pData+n, nSuffix);
+
+    pReader->pData += n+nSuffix;
+    pReader->nData -= n+nSuffix;
   }
-  sqlite3_free(q->pTerms);
-  CLEAR(q);
 }
 
-/* Free all of the dynamically allocated memory held by the
-** Snippet
-*/
-static void snippetClear(Snippet *p){
-  sqlite3_free(p->aMatch);
-  sqlite3_free(p->zOffset);
-  sqlite3_free(p->zSnippet);
-  CLEAR(p);
-}
-/*
-** Append a single entry to the p->aMatch[] log.
+/* strcmp-style comparison of pReader's current term against pTerm.
+** If isPrefix, equality means equal through nTerm bytes.
 */
-static void snippetAppendMatch(
-  Snippet *p,               /* Append the entry to this snippet */
-  int iCol, int iTerm,      /* The column and query term */
-  int iToken,               /* Matching token in document */
-  int iStart, int nByte     /* Offset and size of the match */
-){
-  int i;
-  struct snippetMatch *pMatch;
-  if( p->nMatch+1>=p->nAlloc ){
-    p->nAlloc = p->nAlloc*2 + 10;
-    p->aMatch = sqlite3_realloc(p->aMatch, p->nAlloc*sizeof(p->aMatch[0]) );
-    if( p->aMatch==0 ){
-      p->nMatch = 0;
-      p->nAlloc = 0;
-      return;
-    }
+static int leafReaderTermCmp(LeafReader *pReader,
+                             const char *pTerm, int nTerm, int isPrefix){
+  int c, n = pReader->term.nDataterm.nData : nTerm;
+  if( n==0 ){
+    if( pReader->term.nData>0 ) return -1;
+    if(nTerm>0 ) return 1;
+    return 0;
   }
-  i = p->nMatch++;
-  pMatch = &p->aMatch[i];
-  pMatch->iCol = iCol;
-  pMatch->iTerm = iTerm;
-  pMatch->iToken = iToken;
-  pMatch->iStart = iStart;
-  pMatch->nByte = nByte;
+
+  c = memcmp(pReader->term.pData, pTerm, n);
+  if( c!=0 ) return c;
+  if( isPrefix && n==nTerm ) return 0;
+  return pReader->term.nData - nTerm;
 }
 
-/*
-** Sizing information for the circular buffer used in snippetOffsetsOfColumn()
-*/
-#define FTS3_ROTOR_SZ   (32)
-#define FTS3_ROTOR_MASK (FTS3_ROTOR_SZ-1)
 
-/*
-** Add entries to pSnippet->aMatch[] for every match that occurs against
-** document zDoc[0..nDoc-1] which is stored in column iColumn.
+/****************************************************************/
+/* LeavesReader wraps LeafReader to allow iterating over the entire
+** leaf layer of the tree.
 */
-static void snippetOffsetsOfColumn(
-  Query *pQuery,
-  Snippet *pSnippet,
-  int iColumn,
-  const char *zDoc,
-  int nDoc
-){
-  const sqlite3_tokenizer_module *pTModule;  /* The tokenizer module */
-  sqlite3_tokenizer *pTokenizer;             /* The specific tokenizer */
-  sqlite3_tokenizer_cursor *pTCursor;        /* Tokenizer cursor */
-  fulltext_vtab *pVtab;                /* The full text index */
-  int nColumn;                         /* Number of columns in the index */
-  const QueryTerm *aTerm;              /* Query string terms */
-  int nTerm;                           /* Number of query string terms */  
-  int i, j;                            /* Loop counters */
-  int rc;                              /* Return code */
-  unsigned int match, prevMatch;       /* Phrase search bitmasks */
-  const char *zToken;                  /* Next token from the tokenizer */
-  int nToken;                          /* Size of zToken */
-  int iBegin, iEnd, iPos;              /* Offsets of beginning and end */
-
-  /* The following variables keep a circular buffer of the last
-  ** few tokens */
-  unsigned int iRotor = 0;             /* Index of current token */
-  int iRotorBegin[FTS3_ROTOR_SZ];      /* Beginning offset of token */
-  int iRotorLen[FTS3_ROTOR_SZ];        /* Length of token */
+typedef struct LeavesReader {
+  int idx;                  /* Index within the segment. */
 
-  pVtab = pQuery->pFts;
-  nColumn = pVtab->nColumn;
-  pTokenizer = pVtab->pTokenizer;
-  pTModule = pTokenizer->pModule;
-  rc = pTModule->xOpen(pTokenizer, zDoc, nDoc, &pTCursor);
-  if( rc ) return;
-  pTCursor->pTokenizer = pTokenizer;
-  aTerm = pQuery->pTerms;
-  nTerm = pQuery->nTerms;
-  if( nTerm>=FTS3_ROTOR_SZ ){
-    nTerm = FTS3_ROTOR_SZ - 1;
-  }
-  prevMatch = 0;
-  while(1){
-    rc = pTModule->xNext(pTCursor, &zToken, &nToken, &iBegin, &iEnd, &iPos);
-    if( rc ) break;
-    iRotorBegin[iRotor&FTS3_ROTOR_MASK] = iBegin;
-    iRotorLen[iRotor&FTS3_ROTOR_MASK] = iEnd-iBegin;
-    match = 0;
-    for(i=0; i=0 && iColnToken ) continue;
-      if( !aTerm[i].isPrefix && aTerm[i].nTerm1 && (prevMatch & (1<=0; j--){
-          int k = (iRotor-j) & FTS3_ROTOR_MASK;
-          snippetAppendMatch(pSnippet, iColumn, i-j, iPos-j,
-                iRotorBegin[k], iRotorLen[k]);
-        }
-      }
-    }
-    prevMatch = match<<1;
-    iRotor++;
-  }
-  pTModule->xClose(pTCursor);  
-}
+  sqlite3_stmt *pStmt;      /* Statement we're streaming leaves from. */
+  int eof;                  /* we've seen SQLITE_DONE from pStmt. */
 
-/*
-** Remove entries from the pSnippet structure to account for the NEAR
-** operator. When this is called, pSnippet contains the list of token 
-** offsets produced by treating all NEAR operators as AND operators.
-** This function removes any entries that should not be present after
-** accounting for the NEAR restriction. For example, if the queried
-** document is:
-**
-**     "A B C D E A"
-**
-** and the query is:
-** 
-**     A NEAR/0 E
-**
-** then when this function is called the Snippet contains token offsets
-** 0, 4 and 5. This function removes the "0" entry (because the first A
-** is not near enough to an E).
-*/
-static void trimSnippetOffsetsForNear(Query *pQuery, Snippet *pSnippet){
-  int ii;
-  int iDir = 1;
+  LeafReader leafReader;    /* reader for the current leaf. */
+  DataBuffer rootData;      /* root data for inline. */
+} LeavesReader;
 
-  while(iDir>-2) {
-    assert( iDir==1 || iDir==-1 );
-    for(ii=0; iinMatch; ii++){
-      int jj;
-      int nNear;
-      struct snippetMatch *pMatch = &pSnippet->aMatch[ii];
-      QueryTerm *pQueryTerm = &pQuery->pTerms[pMatch->iTerm];
+/* Access the current term. */
+static int leavesReaderTermBytes(LeavesReader *pReader){
+  assert( !pReader->eof );
+  return leafReaderTermBytes(&pReader->leafReader);
+}
+static const char *leavesReaderTerm(LeavesReader *pReader){
+  assert( !pReader->eof );
+  return leafReaderTerm(&pReader->leafReader);
+}
 
-      if( (pMatch->iTerm+iDir)<0 
-       || (pMatch->iTerm+iDir)>=pQuery->nTerms
-      ){
-        continue;
-      }
-     
-      nNear = pQueryTerm->nNear;
-      if( iDir<0 ){
-        nNear = pQueryTerm[-1].nNear;
-      }
-  
-      if( pMatch->iTerm>=0 && nNear ){
-        int isOk = 0;
-        int iNextTerm = pMatch->iTerm+iDir;
-        int iPrevTerm = iNextTerm;
+/* Access the doclist data for the current term. */
+static int leavesReaderDataBytes(LeavesReader *pReader){
+  assert( !pReader->eof );
+  return leafReaderDataBytes(&pReader->leafReader);
+}
+static const char *leavesReaderData(LeavesReader *pReader){
+  assert( !pReader->eof );
+  return leafReaderData(&pReader->leafReader);
+}
 
-        int iEndToken;
-        int iStartToken;
+static int leavesReaderAtEnd(LeavesReader *pReader){
+  return pReader->eof;
+}
 
-        if( iDir<0 ){
-          int nPhrase = 1;
-          iStartToken = pMatch->iToken;
-          while( (pMatch->iTerm+nPhrase)nTerms 
-              && pQuery->pTerms[pMatch->iTerm+nPhrase].iPhrase>1 
-          ){
-            nPhrase++;
-          }
-          iEndToken = iStartToken + nPhrase - 1;
-        }else{
-          iEndToken   = pMatch->iToken;
-          iStartToken = pMatch->iToken+1-pQueryTerm->iPhrase;
-        }
+/* loadSegmentLeaves() may not read all the way to SQLITE_DONE, thus
+** leaving the statement handle open, which locks the table.
+*/
+/* TODO(shess) This "solution" is not satisfactory.  Really, there
+** should be check-in function for all statement handles which
+** arranges to call sqlite3_reset().  This most likely will require
+** modification to control flow all over the place, though, so for now
+** just punt.
+**
+** Note the the current system assumes that segment merges will run to
+** completion, which is why this particular probably hasn't arisen in
+** this case.  Probably a brittle assumption.
+*/
+static int leavesReaderReset(LeavesReader *pReader){
+  return sqlite3_reset(pReader->pStmt);
+}
 
-        while( pQuery->pTerms[iNextTerm].iPhrase>1 ){
-          iNextTerm--;
-        }
-        while( (iPrevTerm+1)nTerms && 
-               pQuery->pTerms[iPrevTerm+1].iPhrase>1 
-        ){
-          iPrevTerm++;
-        }
-  
-        for(jj=0; isOk==0 && jjnMatch; jj++){
-          struct snippetMatch *p = &pSnippet->aMatch[jj];
-          if( p->iCol==pMatch->iCol && ((
-               p->iTerm==iNextTerm && 
-               p->iToken>iEndToken && 
-               p->iToken<=iEndToken+nNear
-          ) || (
-               p->iTerm==iPrevTerm && 
-               p->iTokeniToken>=iStartToken-nNear
-          ))){
-            isOk = 1;
-          }
-        }
-        if( !isOk ){
-          for(jj=1-pQueryTerm->iPhrase; jj<=0; jj++){
-            pMatch[jj].iTerm = -1;
-          }
-          ii = -1;
-          iDir = 1;
-        }
-      }
-    }
-    iDir -= 2;
+static void leavesReaderDestroy(LeavesReader *pReader){
+  /* If idx is -1, that means we're using a non-cached statement
+  ** handle in the optimize() case, so we need to release it.
+  */
+  if( pReader->pStmt!=NULL && pReader->idx==-1 ){
+    sqlite3_finalize(pReader->pStmt);
   }
+  leafReaderDestroy(&pReader->leafReader);
+  dataBufferDestroy(&pReader->rootData);
+  SCRAMBLE(pReader);
 }
 
-/*
-** Compute all offsets for the current row of the query.  
-** If the offsets have already been computed, this routine is a no-op.
+/* Initialize pReader with the given root data (if iStartBlockid==0
+** the leaf data was entirely contained in the root), or from the
+** stream of blocks between iStartBlockid and iEndBlockid, inclusive.
 */
-static void snippetAllOffsets(fulltext_cursor *p){
-  int nColumn;
-  int iColumn, i;
-  int iFirst, iLast;
-  fulltext_vtab *pFts;
+static int leavesReaderInit(fulltext_vtab *v,
+                            int idx,
+                            sqlite_int64 iStartBlockid,
+                            sqlite_int64 iEndBlockid,
+                            const char *pRootData, int nRootData,
+                            LeavesReader *pReader){
+  CLEAR(pReader);
+  pReader->idx = idx;
 
-  if( p->snippet.nMatch ) return;
-  if( p->q.nTerms==0 ) return;
-  pFts = p->q.pFts;
-  nColumn = pFts->nColumn;
-  iColumn = (p->iCursorType - QUERY_FULLTEXT);
-  if( iColumn<0 || iColumn>=nColumn ){
-    iFirst = 0;
-    iLast = nColumn-1;
+  dataBufferInit(&pReader->rootData, 0);
+  if( iStartBlockid==0 ){
+    /* Entire leaf level fit in root data. */
+    dataBufferReplace(&pReader->rootData, pRootData, nRootData);
+    leafReaderInit(pReader->rootData.pData, pReader->rootData.nData,
+                   &pReader->leafReader);
   }else{
-    iFirst = iColumn;
-    iLast = iColumn;
-  }
-  for(i=iFirst; i<=iLast; i++){
-    const char *zDoc;
-    int nDoc;
-    zDoc = (const char*)sqlite3_column_text(p->pStmt, i+1);
-    nDoc = sqlite3_column_bytes(p->pStmt, i+1);
-    snippetOffsetsOfColumn(&p->q, &p->snippet, i, zDoc, nDoc);
-  }
-
-  trimSnippetOffsetsForNear(&p->q, &p->snippet);
-}
+    sqlite3_stmt *s;
+    int rc = sql_get_leaf_statement(v, idx, &s);
+    if( rc!=SQLITE_OK ) return rc;
 
-/*
-** Convert the information in the aMatch[] array of the snippet
-** into the string zOffset[0..nOffset-1].
-*/
-static void snippetOffsetText(Snippet *p){
-  int i;
-  int cnt = 0;
-  StringBuffer sb;
-  char zBuf[200];
-  if( p->zOffset ) return;
-  initStringBuffer(&sb);
-  for(i=0; inMatch; i++){
-    struct snippetMatch *pMatch = &p->aMatch[i];
-    if( pMatch->iTerm>=0 ){
-      /* If snippetMatch.iTerm is less than 0, then the match was 
-      ** discarded as part of processing the NEAR operator (see the 
-      ** trimSnippetOffsetsForNear() function for details). Ignore 
-      ** it in this case
-      */
-      zBuf[0] = ' ';
-      sprintf(&zBuf[cnt>0], "%d %d %d %d", pMatch->iCol,
-          pMatch->iTerm, pMatch->iStart, pMatch->nByte);
-      append(&sb, zBuf);
-      cnt++;
+    rc = sqlite3_bind_int64(s, 1, iStartBlockid);
+    if( rc!=SQLITE_OK ) return rc;
+
+    rc = sqlite3_bind_int64(s, 2, iEndBlockid);
+    if( rc!=SQLITE_OK ) return rc;
+
+    rc = sqlite3_step(s);
+    if( rc==SQLITE_DONE ){
+      pReader->eof = 1;
+      return SQLITE_OK;
     }
+    if( rc!=SQLITE_ROW ) return rc;
+
+    pReader->pStmt = s;
+    leafReaderInit(sqlite3_column_blob(pReader->pStmt, 0),
+                   sqlite3_column_bytes(pReader->pStmt, 0),
+                   &pReader->leafReader);
   }
-  p->zOffset = stringBufferData(&sb);
-  p->nOffset = stringBufferLength(&sb);
+  return SQLITE_OK;
 }
 
-/*
-** zDoc[0..nDoc-1] is phrase of text.  aMatch[0..nMatch-1] are a set
-** of matching words some of which might be in zDoc.  zDoc is column
-** number iCol.
-**
-** iBreak is suggested spot in zDoc where we could begin or end an
-** excerpt.  Return a value similar to iBreak but possibly adjusted
-** to be a little left or right so that the break point is better.
+/* Step the current leaf forward to the next term.  If we reach the
+** end of the current leaf, step forward to the next leaf block.
 */
-static int wordBoundary(
-  int iBreak,                   /* The suggested break point */
-  const char *zDoc,             /* Document text */
-  int nDoc,                     /* Number of bytes in zDoc[] */
-  struct snippetMatch *aMatch,  /* Matching words */
-  int nMatch,                   /* Number of entries in aMatch[] */
-  int iCol                      /* The column number for zDoc[] */
-){
-  int i;
-  if( iBreak<=10 ){
-    return 0;
-  }
-  if( iBreak>=nDoc-10 ){
-    return nDoc;
-  }
-  for(i=0; i0 && aMatch[i-1].iStart+aMatch[i-1].nByte>=iBreak ){
-      return aMatch[i-1].iStart;
-    }
-  }
-  for(i=1; i<=10; i++){
-    if( safe_isspace(zDoc[iBreak-i]) ){
-      return iBreak - i + 1;
+static int leavesReaderStep(fulltext_vtab *v, LeavesReader *pReader){
+  assert( !leavesReaderAtEnd(pReader) );
+  leafReaderStep(&pReader->leafReader);
+
+  if( leafReaderAtEnd(&pReader->leafReader) ){
+    int rc;
+    if( pReader->rootData.pData ){
+      pReader->eof = 1;
+      return SQLITE_OK;
     }
-    if( safe_isspace(zDoc[iBreak+i]) ){
-      return iBreak + i + 1;
+    rc = sqlite3_step(pReader->pStmt);
+    if( rc!=SQLITE_ROW ){
+      pReader->eof = 1;
+      return rc==SQLITE_DONE ? SQLITE_OK : rc;
     }
+    leafReaderDestroy(&pReader->leafReader);
+    leafReaderInit(sqlite3_column_blob(pReader->pStmt, 0),
+                   sqlite3_column_bytes(pReader->pStmt, 0),
+                   &pReader->leafReader);
   }
-  return iBreak;
+  return SQLITE_OK;
 }
 
+/* Order LeavesReaders by their term, ignoring idx.  Readers at eof
+** always sort to the end.
+*/
+static int leavesReaderTermCmp(LeavesReader *lr1, LeavesReader *lr2){
+  if( leavesReaderAtEnd(lr1) ){
+    if( leavesReaderAtEnd(lr2) ) return 0;
+    return 1;
+  }
+  if( leavesReaderAtEnd(lr2) ) return -1;
 
+  return leafReaderTermCmp(&lr1->leafReader,
+                           leavesReaderTerm(lr2), leavesReaderTermBytes(lr2),
+                           0);
+}
 
-/*
-** Allowed values for Snippet.aMatch[].snStatus
+/* Similar to leavesReaderTermCmp(), with additional ordering by idx
+** so that older segments sort before newer segments.
 */
-#define SNIPPET_IGNORE  0   /* It is ok to omit this match from the snippet */
-#define SNIPPET_DESIRED 1   /* We want to include this match in the snippet */
+static int leavesReaderCmp(LeavesReader *lr1, LeavesReader *lr2){
+  int c = leavesReaderTermCmp(lr1, lr2);
+  if( c!=0 ) return c;
+  return lr1->idx-lr2->idx;
+}
 
-/*
-** Generate the text of a snippet.
+/* Assume that pLr[1]..pLr[nLr] are sorted.  Bubble pLr[0] into its
+** sorted position.
 */
-static void snippetText(
-  fulltext_cursor *pCursor,   /* The cursor we need the snippet for */
-  const char *zStartMark,     /* Markup to appear before each match */
-  const char *zEndMark,       /* Markup to appear after each match */
-  const char *zEllipsis       /* Ellipsis mark */
-){
-  int i, j;
-  struct snippetMatch *aMatch;
-  int nMatch;
-  int nDesired;
-  StringBuffer sb;
-  int tailCol;
-  int tailOffset;
-  int iCol;
-  int nDoc;
-  const char *zDoc;
-  int iStart, iEnd;
-  int tailEllipsis = 0;
-  int iMatch;
-  
+static void leavesReaderReorder(LeavesReader *pLr, int nLr){
+  while( nLr>1 && leavesReaderCmp(pLr, pLr+1)>0 ){
+    LeavesReader tmp = pLr[0];
+    pLr[0] = pLr[1];
+    pLr[1] = tmp;
+    nLr--;
+    pLr++;
+  }
+}
 
-  sqlite3_free(pCursor->snippet.zSnippet);
-  pCursor->snippet.zSnippet = 0;
-  aMatch = pCursor->snippet.aMatch;
-  nMatch = pCursor->snippet.nMatch;
-  initStringBuffer(&sb);
+/* Initializes pReaders with the segments from level iLevel, returning
+** the number of segments in *piReaders.  Leaves pReaders in sorted
+** order.
+*/
+static int leavesReadersInit(fulltext_vtab *v, int iLevel,
+                             LeavesReader *pReaders, int *piReaders){
+  sqlite3_stmt *s;
+  int i, rc = sql_get_statement(v, SEGDIR_SELECT_LEVEL_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-  for(i=0; iq.nTerms; i++){
-    for(j=0; j0 ){
+      leavesReaderDestroy(&pReaders[i]);
     }
+    return rc;
   }
 
-  iMatch = 0;
-  tailCol = -1;
-  tailOffset = 0;
-  for(i=0; i0; i++){
-    if( aMatch[i].snStatus!=SNIPPET_DESIRED ) continue;
-    nDesired--;
-    iCol = aMatch[i].iCol;
-    zDoc = (const char*)sqlite3_column_text(pCursor->pStmt, iCol+1);
-    nDoc = sqlite3_column_bytes(pCursor->pStmt, iCol+1);
-    iStart = aMatch[i].iStart - 40;
-    iStart = wordBoundary(iStart, zDoc, nDoc, aMatch, nMatch, iCol);
-    if( iStart<=10 ){
-      iStart = 0;
-    }
-    if( iCol==tailCol && iStart<=tailOffset+20 ){
-      iStart = tailOffset;
-    }
-    if( (iCol!=tailCol && tailCol>=0) || iStart!=tailOffset ){
-      trimWhiteSpace(&sb);
-      appendWhiteSpace(&sb);
-      append(&sb, zEllipsis);
-      appendWhiteSpace(&sb);
-    }
-    iEnd = aMatch[i].iStart + aMatch[i].nByte + 40;
-    iEnd = wordBoundary(iEnd, zDoc, nDoc, aMatch, nMatch, iCol);
-    if( iEnd>=nDoc-10 ){
-      iEnd = nDoc;
-      tailEllipsis = 0;
-    }else{
-      tailEllipsis = 1;
-    }
-    while( iMatchsnippet.zSnippet = stringBufferData(&sb);
-  pCursor->snippet.nSnippet = stringBufferLength(&sb);
+
+  return leafWriterStepMerge(v, pWriter, pTerm, nTerm, dlReaders, nReaders);
 }
 
+/* Forward ref due to mutual recursion with segdirNextIndex(). */
+static int segmentMerge(fulltext_vtab *v, int iLevel);
 
-/*
-** Close the cursor.  For additional information see the documentation
-** on the xClose method of the virtual table interface.
+/* Put the next available index at iLevel into *pidx.  If iLevel
+** already has MERGE_COUNT segments, they are merged to a higher
+** level to make room.
 */
-static int fulltextClose(sqlite3_vtab_cursor *pCursor){
-  fulltext_cursor *c = (fulltext_cursor *) pCursor;
-  FTSTRACE(("FTS3 Close %p\n", c));
-  sqlite3_finalize(c->pStmt);
-  queryClear(&c->q);
-  snippetClear(&c->snippet);
-  if( c->result.nData!=0 ) dlrDestroy(&c->reader);
-  dataBufferDestroy(&c->result);
-  sqlite3_free(c);
+static int segdirNextIndex(fulltext_vtab *v, int iLevel, int *pidx){
+  int rc = segdir_max_index(v, iLevel, pidx);
+  if( rc==SQLITE_DONE ){              /* No segments at iLevel. */
+    *pidx = 0;
+  }else if( rc==SQLITE_ROW ){
+    if( *pidx==(MERGE_COUNT-1) ){
+      rc = segmentMerge(v, iLevel);
+      if( rc!=SQLITE_OK ) return rc;
+      *pidx = 0;
+    }else{
+      (*pidx)++;
+    }
+  }else{
+    return rc;
+  }
   return SQLITE_OK;
 }
 
-static int fulltextNext(sqlite3_vtab_cursor *pCursor){
-  fulltext_cursor *c = (fulltext_cursor *) pCursor;
-  int rc;
+/* Merge MERGE_COUNT segments at iLevel into a new segment at
+** iLevel+1.  If iLevel+1 is already full of segments, those will be
+** merged to make room.
+*/
+static int segmentMerge(fulltext_vtab *v, int iLevel){
+  LeafWriter writer;
+  LeavesReader lrs[MERGE_COUNT];
+  int i, rc, idx = 0;
 
-  FTSTRACE(("FTS3 Next %p\n", pCursor));
-  snippetClear(&c->snippet);
-  if( c->iCursorType < QUERY_FULLTEXT ){
-    /* TODO(shess) Handle SQLITE_SCHEMA AND SQLITE_BUSY. */
-    rc = sqlite3_step(c->pStmt);
-    switch( rc ){
-      case SQLITE_ROW:
-        c->eof = 0;
-        return SQLITE_OK;
-      case SQLITE_DONE:
-        c->eof = 1;
-        return SQLITE_OK;
-      default:
-        c->eof = 1;
-        return rc;
-    }
-  } else {  /* full-text query */
-    rc = sqlite3_reset(c->pStmt);
-    if( rc!=SQLITE_OK ) return rc;
+  /* Determine the next available segment index at the next level,
+  ** merging as necessary.
+  */
+  rc = segdirNextIndex(v, iLevel+1, &idx);
+  if( rc!=SQLITE_OK ) return rc;
 
-    if( c->result.nData==0 || dlrAtEnd(&c->reader) ){
-      c->eof = 1;
-      return SQLITE_OK;
+  /* TODO(shess) This assumes that we'll always see exactly
+  ** MERGE_COUNT segments to merge at a given level.  That will be
+  ** broken if we allow the developer to request preemptive or
+  ** deferred merging.
+  */
+  memset(&lrs, '\0', sizeof(lrs));
+  rc = leavesReadersInit(v, iLevel, lrs, &i);
+  if( rc!=SQLITE_OK ) return rc;
+  assert( i==MERGE_COUNT );
+
+  leafWriterInit(iLevel+1, idx, &writer);
+
+  /* Since leavesReaderReorder() pushes readers at eof to the end,
+  ** when the first reader is empty, all will be empty.
+  */
+  while( !leavesReaderAtEnd(lrs) ){
+    /* Figure out how many readers share their next term. */
+    for(i=1; ipStmt, 1, dlrDocid(&c->reader));
-    dlrStep(&c->reader);
-    if( rc!=SQLITE_OK ) return rc;
-    /* TODO(shess) Handle SQLITE_SCHEMA AND SQLITE_BUSY. */
-    rc = sqlite3_step(c->pStmt);
-    if( rc==SQLITE_ROW ){   /* the case we expect */
-      c->eof = 0;
-      return SQLITE_OK;
+
+    rc = leavesReadersMerge(v, lrs, i, &writer);
+    if( rc!=SQLITE_OK ) goto err;
+
+    /* Step forward those that were merged. */
+    while( i-->0 ){
+      rc = leavesReaderStep(v, lrs+i);
+      if( rc!=SQLITE_OK ) goto err;
+
+      /* Reorder by term, then by age. */
+      leavesReaderReorder(lrs+i, MERGE_COUNT-i);
     }
-    /* an error occurred; abort */
-    return rc==SQLITE_DONE ? SQLITE_ERROR : rc;
   }
+
+  for(i=0; i=nColumn */
-  QueryTerm *pQTerm,   /* Term we are looking for, or 1st term of a phrase */
-  DataBuffer *pResult  /* Write the result here */
-){
-  DataBuffer left, right, new;
-  int i, rc;
+static int loadSegmentLeavesInt(fulltext_vtab *v, LeavesReader *pReader,
+                                const char *pTerm, int nTerm, int isPrefix,
+                                DataBuffer *out){
+  /* doclist data is accumulated into pBuffers similar to how one does
+  ** increment in binary arithmetic.  If index 0 is empty, the data is
+  ** stored there.  If there is data there, it is merged and the
+  ** results carried into position 1, with further merge-and-carry
+  ** until an empty position is found.
+  */
+  DataBuffer *pBuffers = NULL;
+  int nBuffers = 0, nMaxBuffers = 0, rc;
 
-  /* No phrase search if no position info. */
-  assert( pQTerm->nPhrase==0 || DL_DEFAULT!=DL_DOCIDS );
+  assert( nTerm>0 );
 
-  /* This code should never be called with buffered updates. */
-  assert( v->nPendingData<0 );
+  for(rc=SQLITE_OK; rc==SQLITE_OK && !leavesReaderAtEnd(pReader);
+      rc=leavesReaderStep(v, pReader)){
+    /* TODO(shess) Really want leavesReaderTermCmp(), but that name is
+    ** already taken to compare the terms of two LeavesReaders.  Think
+    ** on a better name.  [Meanwhile, break encapsulation rather than
+    ** use a confusing name.]
+    */
+    int c = leafReaderTermCmp(&pReader->leafReader, pTerm, nTerm, isPrefix);
+    if( c>0 ) break;      /* Past any possible matches. */
+    if( c==0 ){
+      const char *pData = leavesReaderData(pReader);
+      int iBuffer, nData = leavesReaderDataBytes(pReader);
+
+      /* Find the first empty buffer. */
+      for(iBuffer=0; iBuffer0 ){
+            assert(pBuffers!=NULL);
+            memcpy(p, pBuffers, nBuffers*sizeof(*pBuffers));
+            sqlite3_free(pBuffers);
+          }
+          pBuffers = p;
+        }
+        dataBufferInit(&(pBuffers[nBuffers]), 0);
+        nBuffers++;
+      }
+
+      /* At this point, must have an empty at iBuffer. */
+      assert(iBufferpTerm, pQTerm->nTerm, pQTerm->isPrefix,
-                  (0nPhrase ? DL_POSITIONS : DL_DOCIDS), &left);
-  if( rc ) return rc;
-  for(i=1; i<=pQTerm->nPhrase && left.nData>0; i++){
-    /* If this token is connected to the next by a NEAR operator, and
-    ** the next token is the start of a phrase, then set nPhraseRight
-    ** to the number of tokens in the phrase. Otherwise leave it at 1.
-    */
-    int nPhraseRight = 1;
-    while( (i+nPhraseRight)<=pQTerm->nPhrase 
-        && pQTerm[i+nPhraseRight].nNear==0 
-    ){
-      nPhraseRight++;
+        /* Accumulate remaining doclists into pAcc. */
+        for(++p; ppData, p->nData);
+
+          /* dataBufferReset() could allow a large doclist to blow up
+          ** our memory requirements.
+          */
+          if( p->nCapacity<1024 ){
+            dataBufferReset(p);
+          }else{
+            dataBufferDestroy(p);
+            dataBufferInit(p, 0);
+          }
+        }
+      }
     }
+  }
 
-    dataBufferInit(&right, 0);
-    rc = termSelect(v, iColumn, pQTerm[i].pTerm, pQTerm[i].nTerm,
-                    pQTerm[i].isPrefix, DL_POSITIONS, &right);
-    if( rc ){
-      dataBufferDestroy(&left);
-      return rc;
+  /* Union all the doclists together into *out. */
+  /* TODO(shess) What if *out is big?  Sigh. */
+  if( rc==SQLITE_OK && nBuffers>0 ){
+    int iBuffer;
+    for(iBuffer=0; iBuffer0 ){
+        if( out->nData==0 ){
+          dataBufferSwap(out, &(pBuffers[iBuffer]));
+        }else{
+          docListAccumulateUnion(out, pBuffers[iBuffer].pData,
+                                 pBuffers[iBuffer].nData);
+        }
+      }
     }
-    dataBufferInit(&new, 0);
-    docListPhraseMerge(left.pData, left.nData, right.pData, right.nData,
-                       pQTerm[i-1].nNear, pQTerm[i-1].iPhrase + nPhraseRight,
-                       ((inPhrase) ? DL_POSITIONS : DL_DOCIDS),
-                       &new);
-    dataBufferDestroy(&left);
-    dataBufferDestroy(&right);
-    left = new;
   }
-  *pResult = left;
-  return SQLITE_OK;
-}
 
-/* Add a new term pTerm[0..nTerm-1] to the query *q.
-*/
-static void queryAdd(Query *q, const char *pTerm, int nTerm){
-  QueryTerm *t;
-  ++q->nTerms;
-  q->pTerms = sqlite3_realloc(q->pTerms, q->nTerms * sizeof(q->pTerms[0]));
-  if( q->pTerms==0 ){
-    q->nTerms = 0;
-    return;
+  while( nBuffers-- ){
+    dataBufferDestroy(&(pBuffers[nBuffers]));
   }
-  t = &q->pTerms[q->nTerms - 1];
-  CLEAR(t);
-  t->pTerm = sqlite3_malloc(nTerm+1);
-  memcpy(t->pTerm, pTerm, nTerm);
-  t->pTerm[nTerm] = 0;
-  t->nTerm = nTerm;
-  t->isOr = q->nextIsOr;
-  t->isPrefix = 0;
-  q->nextIsOr = 0;
-  t->iColumn = q->nextColumn;
-  q->nextColumn = q->dfltColumn;
+  if( pBuffers!=NULL ) sqlite3_free(pBuffers);
+
+  return rc;
 }
 
-/*
-** Check to see if the string zToken[0...nToken-1] matches any
-** column name in the virtual table.   If it does,
-** return the zero-indexed column number.  If not, return -1.
-*/
-static int checkColumnSpecifier(
-  fulltext_vtab *pVtab,    /* The virtual table */
-  const char *zToken,      /* Text of the token */
-  int nToken               /* Number of characters in the token */
-){
-  int i;
-  for(i=0; inColumn; i++){
-    if( memcmp(pVtab->azColumn[i], zToken, nToken)==0
-        && pVtab->azColumn[i][nToken]==0 ){
-      return i;
-    }
-  }
-  return -1;
+/* Call loadSegmentLeavesInt() with pData/nData as input. */
+static int loadSegmentLeaf(fulltext_vtab *v, const char *pData, int nData,
+                           const char *pTerm, int nTerm, int isPrefix,
+                           DataBuffer *out){
+  LeavesReader reader;
+  int rc;
+
+  assert( nData>1 );
+  assert( *pData=='\0' );
+  rc = leavesReaderInit(v, 0, 0, 0, pData, nData, &reader);
+  if( rc!=SQLITE_OK ) return rc;
+
+  rc = loadSegmentLeavesInt(v, &reader, pTerm, nTerm, isPrefix, out);
+  leavesReaderReset(&reader);
+  leavesReaderDestroy(&reader);
+  return rc;
 }
 
-/*
-** Parse the text at pSegment[0..nSegment-1].  Add additional terms
-** to the query being assemblied in pQuery.
-**
-** inPhrase is true if pSegment[0..nSegement-1] is contained within
-** double-quotes.  If inPhrase is true, then the first term
-** is marked with the number of terms in the phrase less one and
-** OR and "-" syntax is ignored.  If inPhrase is false, then every
-** term found is marked with nPhrase=0 and OR and "-" syntax is significant.
+/* Call loadSegmentLeavesInt() with the leaf nodes from iStartLeaf to
+** iEndLeaf (inclusive) as input, and merge the resulting doclist into
+** out.
 */
-static int tokenizeSegment(
-  sqlite3_tokenizer *pTokenizer,          /* The tokenizer to use */
-  const char *pSegment, int nSegment,     /* Query expression being parsed */
-  int inPhrase,                           /* True if within "..." */
-  Query *pQuery                           /* Append results here */
-){
-  const sqlite3_tokenizer_module *pModule = pTokenizer->pModule;
-  sqlite3_tokenizer_cursor *pCursor;
-  int firstIndex = pQuery->nTerms;
-  int iCol;
-  int nTerm = 1;
-  
-  int rc = pModule->xOpen(pTokenizer, pSegment, nSegment, &pCursor);
+static int loadSegmentLeaves(fulltext_vtab *v,
+                             sqlite_int64 iStartLeaf, sqlite_int64 iEndLeaf,
+                             const char *pTerm, int nTerm, int isPrefix,
+                             DataBuffer *out){
+  int rc;
+  LeavesReader reader;
+
+  assert( iStartLeaf<=iEndLeaf );
+  rc = leavesReaderInit(v, 0, iStartLeaf, iEndLeaf, NULL, 0, &reader);
   if( rc!=SQLITE_OK ) return rc;
-  pCursor->pTokenizer = pTokenizer;
 
-  while( 1 ){
-    const char *pToken;
-    int nToken, iBegin, iEnd, iPos;
+  rc = loadSegmentLeavesInt(v, &reader, pTerm, nTerm, isPrefix, out);
+  leavesReaderReset(&reader);
+  leavesReaderDestroy(&reader);
+  return rc;
+}
 
-    rc = pModule->xNext(pCursor,
-                        &pToken, &nToken,
-                        &iBegin, &iEnd, &iPos);
-    if( rc!=SQLITE_OK ) break;
-    if( !inPhrase &&
-        pSegment[iEnd]==':' &&
-         (iCol = checkColumnSpecifier(pQuery->pFts, pToken, nToken))>=0 ){
-      pQuery->nextColumn = iCol;
-      continue;
-    }
-    if( !inPhrase && pQuery->nTerms>0 && nToken==2 
-     && pSegment[iBegin+0]=='O'
-     && pSegment[iBegin+1]=='R' 
-    ){
-      pQuery->nextIsOr = 1;
-      continue;
-    }
-    if( !inPhrase && pQuery->nTerms>0 && !pQuery->nextIsOr && nToken==4 
-      && pSegment[iBegin+0]=='N' 
-      && pSegment[iBegin+1]=='E' 
-      && pSegment[iBegin+2]=='A' 
-      && pSegment[iBegin+3]=='R' 
-    ){
-      QueryTerm *pTerm = &pQuery->pTerms[pQuery->nTerms-1];
-      if( (iBegin+6)='0' && pSegment[iBegin+5]<='9'
-      ){
-        pTerm->nNear = (pSegment[iBegin+5] - '0');
-        nToken += 2;
-        if( pSegment[iBegin+6]>='0' && pSegment[iBegin+6]<=9 ){
-          pTerm->nNear = pTerm->nNear * 10 + (pSegment[iBegin+6] - '0');
-          iEnd++;
-        }
-        pModule->xNext(pCursor, &pToken, &nToken, &iBegin, &iEnd, &iPos);
-      } else {
-        pTerm->nNear = SQLITE_FTS3_DEFAULT_NEAR_PARAM;
-      }
-      pTerm->nNear++;
-      continue;
-    }
+/* Taking pData/nData as an interior node, find the sequence of child
+** nodes which could include pTerm/nTerm/isPrefix.  Note that the
+** interior node terms logically come between the blocks, so there is
+** one more blockid than there are terms (that block contains terms >=
+** the last interior-node term).
+*/
+/* TODO(shess) The calling code may already know that the end child is
+** not worth calculating, because the end may be in a later sibling
+** node.  Consider whether breaking symmetry is worthwhile.  I suspect
+** it is not worthwhile.
+*/
+static void getChildrenContaining(const char *pData, int nData,
+                                  const char *pTerm, int nTerm, int isPrefix,
+                                  sqlite_int64 *piStartChild,
+                                  sqlite_int64 *piEndChild){
+  InteriorReader reader;
 
-    queryAdd(pQuery, pToken, nToken);
-    if( !inPhrase && iBegin>0 && pSegment[iBegin-1]=='-' ){
-      pQuery->pTerms[pQuery->nTerms-1].isNot = 1;
-    }
-    if( iEndpTerms[pQuery->nTerms-1].isPrefix = 1;
-    }
-    pQuery->pTerms[pQuery->nTerms-1].iPhrase = nTerm;
-    if( inPhrase ){
-      nTerm++;
-    }
+  assert( nData>1 );
+  assert( *pData!='\0' );
+  interiorReaderInit(pData, nData, &reader);
+
+  /* Scan for the first child which could contain pTerm/nTerm. */
+  while( !interiorReaderAtEnd(&reader) ){
+    if( interiorReaderTermCmp(&reader, pTerm, nTerm, 0)>0 ) break;
+    interiorReaderStep(&reader);
   }
+  *piStartChild = interiorReaderCurrentBlockid(&reader);
 
-  if( inPhrase && pQuery->nTerms>firstIndex ){
-    pQuery->pTerms[firstIndex].nPhrase = pQuery->nTerms - firstIndex - 1;
+  /* Keep scanning to find a term greater than our term, using prefix
+  ** comparison if indicated.  If isPrefix is false, this will be the
+  ** same blockid as the starting block.
+  */
+  while( !interiorReaderAtEnd(&reader) ){
+    if( interiorReaderTermCmp(&reader, pTerm, nTerm, isPrefix)>0 ) break;
+    interiorReaderStep(&reader);
   }
+  *piEndChild = interiorReaderCurrentBlockid(&reader);
 
-  return pModule->xClose(pCursor);
+  interiorReaderDestroy(&reader);
+
+  /* Children must ascend, and if !prefix, both must be the same. */
+  assert( *piEndChild>=*piStartChild );
+  assert( isPrefix || *piStartChild==*piEndChild );
 }
 
-/* Parse a query string, yielding a Query object pQuery.
-**
-** The calling function will need to queryClear() to clean up
-** the dynamically allocated memory held by pQuery.
+/* Read block at iBlockid and pass it with other params to
+** getChildrenContaining().
 */
-static int parseQuery(
-  fulltext_vtab *v,        /* The fulltext index */
-  const char *zInput,      /* Input text of the query string */
-  int nInput,              /* Size of the input text */
-  int dfltColumn,          /* Default column of the index to match against */
-  Query *pQuery            /* Write the parse results here. */
+static int loadAndGetChildrenContaining(
+  fulltext_vtab *v,
+  sqlite_int64 iBlockid,
+  const char *pTerm, int nTerm, int isPrefix,
+  sqlite_int64 *piStartChild, sqlite_int64 *piEndChild
 ){
-  int iInput, inPhrase = 0;
-  int ii;
-  QueryTerm *aTerm;
+  sqlite3_stmt *s = NULL;
+  int rc;
 
-  if( zInput==0 ) nInput = 0;
-  if( nInput<0 ) nInput = strlen(zInput);
-  pQuery->nTerms = 0;
-  pQuery->pTerms = NULL;
-  pQuery->nextIsOr = 0;
-  pQuery->nextColumn = dfltColumn;
-  pQuery->dfltColumn = dfltColumn;
-  pQuery->pFts = v;
+  assert( iBlockid!=0 );
+  assert( pTerm!=NULL );
+  assert( nTerm!=0 );        /* TODO(shess) Why not allow this? */
+  assert( piStartChild!=NULL );
+  assert( piEndChild!=NULL );
 
-  for(iInput=0; iInputiInput ){
-      tokenizeSegment(v->pTokenizer, zInput+iInput, i-iInput, inPhrase,
-                       pQuery);
-    }
-    iInput = i;
-    if( ipTerms;
-  for(ii=0; iinTerms; ii++){
-    if( aTerm[ii].nNear || aTerm[ii].nPhrase ){
-      while (aTerm[ii+aTerm[ii].nPhrase].nNear) {
-        aTerm[ii].nPhrase += (1 + aTerm[ii+aTerm[ii].nPhrase+1].nPhrase);
-      }
-    }
-  }
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_DONE ) return SQLITE_ERROR;
+  if( rc!=SQLITE_ROW ) return rc;
+
+  getChildrenContaining(sqlite3_column_blob(s, 0), sqlite3_column_bytes(s, 0),
+                        pTerm, nTerm, isPrefix, piStartChild, piEndChild);
+
+  /* We expect only one row.  We must execute another sqlite3_step()
+   * to complete the iteration; otherwise the table will remain
+   * locked. */
+  rc = sqlite3_step(s);
+  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
+  if( rc!=SQLITE_DONE ) return rc;
 
   return SQLITE_OK;
 }
 
-/* TODO(shess) Refactor the code to remove this forward decl. */
-static int flushPendingTerms(fulltext_vtab *v);
-
-/* Perform a full-text query using the search expression in
-** zInput[0..nInput-1].  Return a list of matching documents
-** in pResult.
-**
-** Queries must match column iColumn.  Or if iColumn>=nColumn
-** they are allowed to match against any column.
+/* Traverse the tree represented by pData[nData] looking for
+** pTerm[nTerm], placing its doclist into *out.  This is internal to
+** loadSegment() to make error-handling cleaner.
 */
-static int fulltextQuery(
-  fulltext_vtab *v,      /* The full text index */
-  int iColumn,           /* Match against this column by default */
-  const char *zInput,    /* The query string */
-  int nInput,            /* Number of bytes in zInput[] */
-  DataBuffer *pResult,   /* Write the result doclist here */
-  Query *pQuery          /* Put parsed query string here */
-){
-  int i, iNext, rc;
-  DataBuffer left, right, or, new;
-  int nNot = 0;
-  QueryTerm *aTerm;
+static int loadSegmentInt(fulltext_vtab *v, const char *pData, int nData,
+                          sqlite_int64 iLeavesEnd,
+                          const char *pTerm, int nTerm, int isPrefix,
+                          DataBuffer *out){
+  /* Special case where root is a leaf. */
+  if( *pData=='\0' ){
+    return loadSegmentLeaf(v, pData, nData, pTerm, nTerm, isPrefix, out);
+  }else{
+    int rc;
+    sqlite_int64 iStartChild, iEndChild;
 
-  /* TODO(shess) Instead of flushing pendingTerms, we could query for
-  ** the relevant term and merge the doclist into what we receive from
-  ** the database.  Wait and see if this is a common issue, first.
-  **
-  ** A good reason not to flush is to not generate update-related
-  ** error codes from here.
-  */
+    /* Process pData as an interior node, then loop down the tree
+    ** until we find the set of leaf nodes to scan for the term.
+    */
+    getChildrenContaining(pData, nData, pTerm, nTerm, isPrefix,
+                          &iStartChild, &iEndChild);
+    while( iStartChild>iLeavesEnd ){
+      sqlite_int64 iNextStart, iNextEnd;
+      rc = loadAndGetChildrenContaining(v, iStartChild, pTerm, nTerm, isPrefix,
+                                        &iNextStart, &iNextEnd);
+      if( rc!=SQLITE_OK ) return rc;
 
-  /* Flush any buffered updates before executing the query. */
-  rc = flushPendingTerms(v);
-  if( rc!=SQLITE_OK ) return rc;
+      /* If we've branched, follow the end branch, too. */
+      if( iStartChild!=iEndChild ){
+        sqlite_int64 iDummy;
+        rc = loadAndGetChildrenContaining(v, iEndChild, pTerm, nTerm, isPrefix,
+                                          &iDummy, &iNextEnd);
+        if( rc!=SQLITE_OK ) return rc;
+      }
 
-  /* TODO(shess) I think that the queryClear() calls below are not
-  ** necessary, because fulltextClose() already clears the query.
-  */
-  rc = parseQuery(v, zInput, nInput, iColumn, pQuery);
-  if( rc!=SQLITE_OK ) return rc;
+      assert( iNextStart<=iNextEnd );
+      iStartChild = iNextStart;
+      iEndChild = iNextEnd;
+    }
+    assert( iStartChild<=iLeavesEnd );
+    assert( iEndChild<=iLeavesEnd );
 
-  /* Empty or NULL queries return no results. */
-  if( pQuery->nTerms==0 ){
-    dataBufferInit(pResult, 0);
-    return SQLITE_OK;
+    /* Scan through the leaf segments for doclists. */
+    return loadSegmentLeaves(v, iStartChild, iEndChild,
+                             pTerm, nTerm, isPrefix, out);
   }
+}
 
-  /* Merge AND terms. */
-  /* TODO(shess) I think we can early-exit if( i>nNot && left.nData==0 ). */
-  aTerm = pQuery->pTerms;
-  for(i = 0; inTerms; i=iNext){
-    if( aTerm[i].isNot ){
-      /* Handle all NOT terms in a separate pass */
-      nNot++;
-      iNext = i + aTerm[i].nPhrase+1;
-      continue;
-    }
-    iNext = i + aTerm[i].nPhrase + 1;
-    rc = docListOfTerm(v, aTerm[i].iColumn, &aTerm[i], &right);
-    if( rc ){
-      if( i!=nNot ) dataBufferDestroy(&left);
-      queryClear(pQuery);
-      return rc;
-    }
-    while( iNextnTerms && aTerm[iNext].isOr ){
-      rc = docListOfTerm(v, aTerm[iNext].iColumn, &aTerm[iNext], &or);
-      iNext += aTerm[iNext].nPhrase + 1;
-      if( rc ){
-        if( i!=nNot ) dataBufferDestroy(&left);
-        dataBufferDestroy(&right);
-        queryClear(pQuery);
-        return rc;
-      }
-      dataBufferInit(&new, 0);
-      docListOrMerge(right.pData, right.nData, or.pData, or.nData, &new);
-      dataBufferDestroy(&right);
-      dataBufferDestroy(&or);
-      right = new;
-    }
-    if( i==nNot ){           /* first term processed. */
-      left = right;
+/* Call loadSegmentInt() to collect the doclist for pTerm/nTerm, then
+** merge its doclist over *out (any duplicate doclists read from the
+** segment rooted at pData will overwrite those in *out).
+*/
+/* TODO(shess) Consider changing this to determine the depth of the
+** leaves using either the first characters of interior nodes (when
+** ==1, we're one level above the leaves), or the first character of
+** the root (which will describe the height of the tree directly).
+** Either feels somewhat tricky to me.
+*/
+/* TODO(shess) The current merge is likely to be slow for large
+** doclists (though it should process from newest/smallest to
+** oldest/largest, so it may not be that bad).  It might be useful to
+** modify things to allow for N-way merging.  This could either be
+** within a segment, with pairwise merges across segments, or across
+** all segments at once.
+*/
+static int loadSegment(fulltext_vtab *v, const char *pData, int nData,
+                       sqlite_int64 iLeavesEnd,
+                       const char *pTerm, int nTerm, int isPrefix,
+                       DataBuffer *out){
+  DataBuffer result;
+  int rc;
+
+  assert( nData>1 );
+
+  /* This code should never be called with buffered updates. */
+  assert( v->nPendingData<0 );
+
+  dataBufferInit(&result, 0);
+  rc = loadSegmentInt(v, pData, nData, iLeavesEnd,
+                      pTerm, nTerm, isPrefix, &result);
+  if( rc==SQLITE_OK && result.nData>0 ){
+    if( out->nData==0 ){
+      DataBuffer tmp = *out;
+      *out = result;
+      result = tmp;
     }else{
-      dataBufferInit(&new, 0);
-      docListAndMerge(left.pData, left.nData, right.pData, right.nData, &new);
-      dataBufferDestroy(&right);
-      dataBufferDestroy(&left);
-      left = new;
+      DataBuffer merged;
+      DLReader readers[2];
+
+      dlrInit(&readers[0], DL_DEFAULT, out->pData, out->nData);
+      dlrInit(&readers[1], DL_DEFAULT, result.pData, result.nData);
+      dataBufferInit(&merged, out->nData+result.nData);
+      docListMerge(&merged, readers, 2);
+      dataBufferDestroy(out);
+      *out = merged;
+      dlrDestroy(&readers[0]);
+      dlrDestroy(&readers[1]);
     }
   }
+  dataBufferDestroy(&result);
+  return rc;
+}
 
-  if( nNot==pQuery->nTerms ){
-    /* We do not yet know how to handle a query of only NOT terms */
-    return SQLITE_ERROR;
-  }
+/* Scan the database and merge together the posting lists for the term
+** into *out.
+*/
+static int termSelect(fulltext_vtab *v, int iColumn,
+                      const char *pTerm, int nTerm, int isPrefix,
+                      DocListType iType, DataBuffer *out){
+  DataBuffer doclist;
+  sqlite3_stmt *s;
+  int rc = sql_get_statement(v, SEGDIR_SELECT_ALL_STMT, &s);
+  if( rc!=SQLITE_OK ) return rc;
 
-  /* Do the EXCEPT terms */
-  for(i=0; inTerms;  i += aTerm[i].nPhrase + 1){
-    if( !aTerm[i].isNot ) continue;
-    rc = docListOfTerm(v, aTerm[i].iColumn, &aTerm[i], &right);
-    if( rc ){
-      queryClear(pQuery);
-      dataBufferDestroy(&left);
-      return rc;
+  /* This code should never be called with buffered updates. */
+  assert( v->nPendingData<0 );
+
+  dataBufferInit(&doclist, 0);
+
+  /* Traverse the segments from oldest to newest so that newer doclist
+  ** elements for given docids overwrite older elements.
+  */
+  while( (rc = sqlite3_step(s))==SQLITE_ROW ){
+    const char *pData = sqlite3_column_blob(s, 2);
+    const int nData = sqlite3_column_bytes(s, 2);
+    const sqlite_int64 iLeavesEnd = sqlite3_column_int64(s, 1);
+    rc = loadSegment(v, pData, nData, iLeavesEnd, pTerm, nTerm, isPrefix,
+                     &doclist);
+    if( rc!=SQLITE_OK ) goto err;
+  }
+  if( rc==SQLITE_DONE ){
+    if( doclist.nData!=0 ){
+      /* TODO(shess) The old term_select_all() code applied the column
+      ** restrict as we merged segments, leading to smaller buffers.
+      ** This is probably worthwhile to bring back, once the new storage
+      ** system is checked in.
+      */
+      if( iColumn==v->nColumn) iColumn = -1;
+      docListTrim(DL_DEFAULT, doclist.pData, doclist.nData,
+                  iColumn, iType, out);
     }
-    dataBufferInit(&new, 0);
-    docListExceptMerge(left.pData, left.nData, right.pData, right.nData, &new);
-    dataBufferDestroy(&right);
-    dataBufferDestroy(&left);
-    left = new;
+    rc = SQLITE_OK;
   }
 
-  *pResult = left;
+ err:
+  dataBufferDestroy(&doclist);
   return rc;
 }
 
-/*
-** This is the xFilter interface for the virtual table.  See
-** the virtual table xFilter method documentation for additional
-** information.
-**
-** If idxNum==QUERY_GENERIC then do a full table scan against
-** the %_content table.
-**
-** If idxNum==QUERY_DOCID then do a docid lookup for a single entry
-** in the %_content table.
-**
-** If idxNum>=QUERY_FULLTEXT then use the full text index.  The
-** column on the left-hand side of the MATCH operator is column
-** number idxNum-QUERY_FULLTEXT, 0 indexed.  argv[0] is the right-hand
-** side of the MATCH operator.
-*/
-/* TODO(shess) Upgrade the cursor initialization and destruction to
-** account for fulltextFilter() being called multiple times on the
-** same cursor.  The current solution is very fragile.  Apply fix to
-** fts3 as appropriate.
+/****************************************************************/
+/* Used to hold hashtable data for sorting. */
+typedef struct TermData {
+  const char *pTerm;
+  int nTerm;
+  DLCollector *pCollector;
+} TermData;
+
+/* Orders TermData elements in strcmp fashion ( <0 for less-than, 0
+** for equal, >0 for greater-than).
 */
-static int fulltextFilter(
-  sqlite3_vtab_cursor *pCursor,     /* The cursor used for this query */
-  int idxNum, const char *idxStr,   /* Which indexing scheme to use */
-  int argc, sqlite3_value **argv    /* Arguments for the indexing scheme */
-){
-  fulltext_cursor *c = (fulltext_cursor *) pCursor;
-  fulltext_vtab *v = cursor_vtab(c);
-  int rc;
-  StringBuffer sb;
+static int termDataCmp(const void *av, const void *bv){
+  const TermData *a = (const TermData *)av;
+  const TermData *b = (const TermData *)bv;
+  int n = a->nTermnTerm ? a->nTerm : b->nTerm;
+  int c = memcmp(a->pTerm, b->pTerm, n);
+  if( c!=0 ) return c;
+  return a->nTerm-b->nTerm;
+}
 
-  FTSTRACE(("FTS3 Filter %p\n",pCursor));
+/* Order pTerms data by term, then write a new level 0 segment using
+** LeafWriter.
+*/
+static int writeZeroSegment(fulltext_vtab *v, fts3Hash *pTerms){
+  fts3HashElem *e;
+  int idx, rc, i, n;
+  TermData *pData;
+  LeafWriter writer;
+  DataBuffer dl;
 
-  initStringBuffer(&sb);
-  append(&sb, "SELECT docid, ");
-  appendList(&sb, v->nColumn, v->azContentColumn);
-  append(&sb, " FROM %_content");
-  if( idxNum!=QUERY_GENERIC ) append(&sb, " WHERE docid = ?");
-  sqlite3_finalize(c->pStmt);
-  rc = sql_prepare(v->db, v->zDb, v->zName, &c->pStmt, stringBufferData(&sb));
-  stringBufferDestroy(&sb);
+  /* Determine the next index at level 0, merging as necessary. */
+  rc = segdirNextIndex(v, 0, &idx);
   if( rc!=SQLITE_OK ) return rc;
 
-  c->iCursorType = idxNum;
-  switch( idxNum ){
-    case QUERY_GENERIC:
-      break;
+  n = fts3HashCount(pTerms);
+  pData = sqlite3_malloc(n*sizeof(TermData));
 
-    case QUERY_DOCID:
-      rc = sqlite3_bind_int64(c->pStmt, 1, sqlite3_value_int64(argv[0]));
-      if( rc!=SQLITE_OK ) return rc;
-      break;
+  for(i = 0, e = fts3HashFirst(pTerms); e; i++, e = fts3HashNext(e)){
+    assert( inColumn);
-      assert( argc==1 );
-      queryClear(&c->q);
-      if( c->result.nData!=0 ){
-        /* This case happens if the same cursor is used repeatedly. */
-        dlrDestroy(&c->reader);
-        dataBufferReset(&c->result);
-      }else{
-        dataBufferInit(&c->result, 0);
-      }
-      rc = fulltextQuery(v, idxNum-QUERY_FULLTEXT, zQuery, -1, &c->result, &c->q);
-      if( rc!=SQLITE_OK ) return rc;
-      if( c->result.nData!=0 ){
-        dlrInit(&c->reader, DL_DOCIDS, c->result.pData, c->result.nData);
-      }
-      break;
-    }
+  /* TODO(shess) Should we allow user-defined collation sequences,
+  ** here?  I think we only need that once we support prefix searches.
+  */
+  if( n>1 ) qsort(pData, n, sizeof(*pData), termDataCmp);
+
+  /* TODO(shess) Refactor so that we can write directly to the segment
+  ** DataBuffer, as happens for segment merges.
+  */
+  leafWriterInit(0, idx, &writer);
+  dataBufferInit(&dl, 0);
+  for(i=0; ieof;
+/* If pendingTerms has data, free it. */
+static int clearPendingTerms(fulltext_vtab *v){
+  if( v->nPendingData>=0 ){
+    fts3HashElem *e;
+    for(e=fts3HashFirst(&v->pendingTerms); e; e=fts3HashNext(e)){
+      dlcDelete(fts3HashData(e));
+    }
+    fts3HashClear(&v->pendingTerms);
+    v->nPendingData = -1;
+  }
+  return SQLITE_OK;
 }
 
-/* This is the xColumn method of the virtual table.  The SQLite
-** core calls this method during a query when it needs the value
-** of a column from the virtual table.  This method needs to use
-** one of the sqlite3_result_*() routines to store the requested
-** value back in the pContext.
+/* If pendingTerms has data, flush it to a level-zero segment, and
+** free it.
 */
-static int fulltextColumn(sqlite3_vtab_cursor *pCursor,
-                          sqlite3_context *pContext, int idxCol){
-  fulltext_cursor *c = (fulltext_cursor *) pCursor;
-  fulltext_vtab *v = cursor_vtab(c);
-
-  if( idxColnColumn ){
-    sqlite3_value *pVal = sqlite3_column_value(c->pStmt, idxCol+1);
-    sqlite3_result_value(pContext, pVal);
-  }else if( idxCol==v->nColumn ){
-    /* The extra column whose name is the same as the table.
-    ** Return a blob which is a pointer to the cursor
-    */
-    sqlite3_result_blob(pContext, &c, sizeof(c), SQLITE_TRANSIENT);
-  }else if( idxCol==v->nColumn+1 ){
-    /* The docid column, which is an alias for rowid. */
-    sqlite3_value *pVal = sqlite3_column_value(c->pStmt, 0);
-    sqlite3_result_value(pContext, pVal);
+static int flushPendingTerms(fulltext_vtab *v){
+  if( v->nPendingData>=0 ){
+    int rc = writeZeroSegment(v, &v->pendingTerms);
+    if( rc==SQLITE_OK ) clearPendingTerms(v);
+    return rc;
   }
   return SQLITE_OK;
 }
 
-/* This is the xRowid method.  The SQLite core calls this routine to
-** retrieve the rowid for the current row of the result set.  fts3
-** exposes %_content.docid as the rowid for the virtual table.  The
-** rowid should be written to *pRowid.
+/* If pendingTerms is "too big", or docid is out of order, flush it.
+** Regardless, be certain that pendingTerms is initialized for use.
 */
-static int fulltextRowid(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){
-  fulltext_cursor *c = (fulltext_cursor *) pCursor;
-
-  *pRowid = sqlite3_column_int64(c->pStmt, 0);
+static int initPendingTerms(fulltext_vtab *v, sqlite_int64 iDocid){
+  /* TODO(shess) Explore whether partially flushing the buffer on
+  ** forced-flush would provide better performance.  I suspect that if
+  ** we ordered the doclists by size and flushed the largest until the
+  ** buffer was half empty, that would let the less frequent terms
+  ** generate longer doclists.
+  */
+  if( iDocid<=v->iPrevDocid || v->nPendingData>kPendingThreshold ){
+    int rc = flushPendingTerms(v);
+    if( rc!=SQLITE_OK ) return rc;
+  }
+  if( v->nPendingData<0 ){
+    fts3HashInit(&v->pendingTerms, FTS3_HASH_STRING, 1);
+    v->nPendingData = 0;
+  }
+  v->iPrevDocid = iDocid;
   return SQLITE_OK;
 }
 
-/* Add all terms in [zText] to pendingTerms table.  If [iColumn] > 0,
-** we also store positions and offsets in the hash table using that
-** column number.
-*/
-static int buildTerms(fulltext_vtab *v, sqlite_int64 iDocid,
-                      const char *zText, int iColumn){
-  sqlite3_tokenizer *pTokenizer = v->pTokenizer;
-  sqlite3_tokenizer_cursor *pCursor;
-  const char *pToken;
-  int nTokenBytes;
-  int iStartOffset, iEndOffset, iPosition;
+/* This function implements the xUpdate callback; it is the top-level entry
+ * point for inserting, deleting or updating a row in a full-text table. */
+static int fulltextUpdate(sqlite3_vtab *pVtab, int nArg, sqlite3_value **ppArg,
+                          sqlite_int64 *pRowid){
+  fulltext_vtab *v = (fulltext_vtab *) pVtab;
   int rc;
 
-  rc = pTokenizer->pModule->xOpen(pTokenizer, zText, -1, &pCursor);
-  if( rc!=SQLITE_OK ) return rc;
-
-  pCursor->pTokenizer = pTokenizer;
-  while( SQLITE_OK==(rc=pTokenizer->pModule->xNext(pCursor,
-                                                   &pToken, &nTokenBytes,
-                                                   &iStartOffset, &iEndOffset,
-                                                   &iPosition)) ){
-    DLCollector *p;
-    int nData;                   /* Size of doclist before our update. */
+  FTSTRACE(("FTS3 Update %p\n", pVtab));
 
-    /* Positions can't be negative; we use -1 as a terminator
-     * internally.  Token can't be NULL or empty. */
-    if( iPosition<0 || pToken == NULL || nTokenBytes == 0 ){
-      rc = SQLITE_ERROR;
-      break;
+  if( nArg<2 ){
+    rc = index_delete(v, sqlite3_value_int64(ppArg[0]));
+    if( rc==SQLITE_OK ){
+      /* If we just deleted the last row in the table, clear out the
+      ** index data.
+      */
+      rc = content_exists(v);
+      if( rc==SQLITE_ROW ){
+        rc = SQLITE_OK;
+      }else if( rc==SQLITE_DONE ){
+        /* Clear the pending terms so we don't flush a useless level-0
+        ** segment when the transaction closes.
+        */
+        rc = clearPendingTerms(v);
+        if( rc==SQLITE_OK ){
+          rc = segdir_delete_all(v);
+        }
+      }
     }
-
-    p = fts3HashFind(&v->pendingTerms, pToken, nTokenBytes);
-    if( p==NULL ){
-      nData = 0;
-      p = dlcNew(iDocid, DL_DEFAULT);
-      fts3HashInsert(&v->pendingTerms, pToken, nTokenBytes, p);
-
-      /* Overhead for our hash table entry, the key, and the value. */
-      v->nPendingData += sizeof(struct fts3HashElem)+sizeof(*p)+nTokenBytes;
+  } else if( sqlite3_value_type(ppArg[0]) != SQLITE_NULL ){
+    /* An update:
+     * ppArg[0] = old rowid
+     * ppArg[1] = new rowid
+     * ppArg[2..2+v->nColumn-1] = values
+     * ppArg[2+v->nColumn] = value for magic column (we ignore this)
+     * ppArg[2+v->nColumn+1] = value for docid
+     */
+    sqlite_int64 rowid = sqlite3_value_int64(ppArg[0]);
+    if( sqlite3_value_type(ppArg[1]) != SQLITE_INTEGER ||
+        sqlite3_value_int64(ppArg[1]) != rowid ){
+      rc = SQLITE_ERROR;  /* we don't allow changing the rowid */
+    }else if( sqlite3_value_type(ppArg[2+v->nColumn+1]) != SQLITE_INTEGER ||
+              sqlite3_value_int64(ppArg[2+v->nColumn+1]) != rowid ){
+      rc = SQLITE_ERROR;  /* we don't allow changing the docid */
     }else{
-      nData = p->b.nData;
-      if( p->dlw.iPrevDocid!=iDocid ) dlcNext(p, iDocid);
+      assert( nArg==2+v->nColumn+2);
+      rc = index_update(v, rowid, &ppArg[2]);
     }
-    if( iColumn>=0 ){
-      dlcAddPos(p, iColumn, iPosition, iStartOffset, iEndOffset);
+  } else {
+    /* An insert:
+     * ppArg[1] = requested rowid
+     * ppArg[2..2+v->nColumn-1] = values
+     * ppArg[2+v->nColumn] = value for magic column (we ignore this)
+     * ppArg[2+v->nColumn+1] = value for docid
+     */
+    sqlite3_value *pRequestDocid = ppArg[2+v->nColumn+1];
+    assert( nArg==2+v->nColumn+2);
+    if( SQLITE_NULL != sqlite3_value_type(pRequestDocid) &&
+        SQLITE_NULL != sqlite3_value_type(ppArg[1]) ){
+      /* TODO(shess) Consider allowing this to work if the values are
+      ** identical.  I'm inclined to discourage that usage, though,
+      ** given that both rowid and docid are special columns.  Better
+      ** would be to define one or the other as the default winner,
+      ** but should it be fts3-centric (docid) or SQLite-centric
+      ** (rowid)?
+      */
+      rc = SQLITE_ERROR;
+    }else{
+      if( SQLITE_NULL == sqlite3_value_type(pRequestDocid) ){
+        pRequestDocid = ppArg[1];
+      }
+      rc = index_insert(v, pRequestDocid, &ppArg[2], pRowid);
     }
-
-    /* Accumulate data added by dlcNew or dlcNext, and dlcAddPos. */
-    v->nPendingData += p->b.nData-nData;
   }
 
-  /* TODO(shess) Check return?  Should this be able to cause errors at
-  ** this point?  Actually, same question about sqlite3_finalize(),
-  ** though one could argue that failure there means that the data is
-  ** not durable.  *ponder*
-  */
-  pTokenizer->pModule->xClose(pCursor);
-  if( SQLITE_DONE == rc ) return SQLITE_OK;
   return rc;
 }
 
-/* Add doclists for all terms in [pValues] to pendingTerms table. */
-static int insertTerms(fulltext_vtab *v, sqlite_int64 iDocid,
-                       sqlite3_value **pValues){
-  int i;
-  for(i = 0; i < v->nColumn ; ++i){
-    char *zText = (char*)sqlite3_value_text(pValues[i]);
-    int rc = buildTerms(v, iDocid, zText, i);
-    if( rc!=SQLITE_OK ) return rc;
-  }
-  return SQLITE_OK;
+static int fulltextSync(sqlite3_vtab *pVtab){
+  FTSTRACE(("FTS3 xSync()\n"));
+  return flushPendingTerms((fulltext_vtab *)pVtab);
 }
 
-/* Add empty doclists for all terms in the given row's content to
-** pendingTerms.
-*/
-static int deleteTerms(fulltext_vtab *v, sqlite_int64 iDocid){
-  const char **pValues;
-  int i, rc;
-
-  /* TODO(shess) Should we allow such tables at all? */
-  if( DL_DEFAULT==DL_DOCIDS ) return SQLITE_ERROR;
+static int fulltextBegin(sqlite3_vtab *pVtab){
+  fulltext_vtab *v = (fulltext_vtab *) pVtab;
+  FTSTRACE(("FTS3 xBegin()\n"));
 
-  rc = content_select(v, iDocid, &pValues);
-  if( rc!=SQLITE_OK ) return rc;
+  /* Any buffered updates should have been cleared by the previous
+  ** transaction.
+  */
+  assert( v->nPendingData<0 );
+  return clearPendingTerms(v);
+}
 
-  for(i = 0 ; i < v->nColumn; ++i) {
-    rc = buildTerms(v, iDocid, pValues[i], -1);
-    if( rc!=SQLITE_OK ) break;
-  }
+static int fulltextCommit(sqlite3_vtab *pVtab){
+  fulltext_vtab *v = (fulltext_vtab *) pVtab;
+  FTSTRACE(("FTS3 xCommit()\n"));
 
-  freeStringArray(v->nColumn, pValues);
-  return SQLITE_OK;
+  /* Buffered updates should have been cleared by fulltextSync(). */
+  assert( v->nPendingData<0 );
+  return clearPendingTerms(v);
 }
 
-/* TODO(shess) Refactor the code to remove this forward decl. */
-static int initPendingTerms(fulltext_vtab *v, sqlite_int64 iDocid);
+static int fulltextRollback(sqlite3_vtab *pVtab){
+  FTSTRACE(("FTS3 xRollback()\n"));
+  return clearPendingTerms((fulltext_vtab *)pVtab);
+}
 
-/* Insert a row into the %_content table; set *piDocid to be the ID of the
-** new row.  Add doclists for terms to pendingTerms.
+/*
+** Implementation of the snippet() function for FTS3
 */
-static int index_insert(fulltext_vtab *v, sqlite3_value *pRequestDocid,
-                        sqlite3_value **pValues, sqlite_int64 *piDocid){
-  int rc;
+static void snippetFunc(
+  sqlite3_context *pContext,
+  int argc,
+  sqlite3_value **argv
+){
+  fulltext_cursor *pCursor;
+  if( argc<1 ) return;
+  if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
+      sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
+    sqlite3_result_error(pContext, "illegal first argument to html_snippet",-1);
+  }else{
+    const char *zStart = "";
+    const char *zEnd = "";
+    const char *zEllipsis = "...";
+    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
+    if( argc>=2 ){
+      zStart = (const char*)sqlite3_value_text(argv[1]);
+      if( argc>=3 ){
+        zEnd = (const char*)sqlite3_value_text(argv[2]);
+        if( argc>=4 ){
+          zEllipsis = (const char*)sqlite3_value_text(argv[3]);
+        }
+      }
+    }
+    snippetAllOffsets(pCursor);
+    snippetText(pCursor, zStart, zEnd, zEllipsis);
+    sqlite3_result_text(pContext, pCursor->snippet.zSnippet,
+                        pCursor->snippet.nSnippet, SQLITE_STATIC);
+  }
+}
 
-  rc = content_insert(v, pRequestDocid, pValues);  /* execute an SQL INSERT */
-  if( rc!=SQLITE_OK ) return rc;
+/*
+** Implementation of the offsets() function for FTS3
+*/
+static void snippetOffsetsFunc(
+  sqlite3_context *pContext,
+  int argc,
+  sqlite3_value **argv
+){
+  fulltext_cursor *pCursor;
+  if( argc<1 ) return;
+  if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
+      sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
+    sqlite3_result_error(pContext, "illegal first argument to offsets",-1);
+  }else{
+    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
+    snippetAllOffsets(pCursor);
+    snippetOffsetText(&pCursor->snippet);
+    sqlite3_result_text(pContext,
+                        pCursor->snippet.zOffset, pCursor->snippet.nOffset,
+                        SQLITE_STATIC);
+  }
+}
 
-  /* docid column is an alias for rowid. */
-  *piDocid = sqlite3_last_insert_rowid(v->db);
-  rc = initPendingTerms(v, *piDocid);
-  if( rc!=SQLITE_OK ) return rc;
+/* OptLeavesReader is nearly identical to LeavesReader, except that
+** where LeavesReader is geared towards the merging of complete
+** segment levels (with exactly MERGE_COUNT segments), OptLeavesReader
+** is geared towards implementation of the optimize() function, and
+** can merge all segments simultaneously.  This version may be
+** somewhat less efficient than LeavesReader because it merges into an
+** accumulator rather than doing an N-way merge, but since segment
+** size grows exponentially (so segment count logrithmically) this is
+** probably not an immediate problem.
+*/
+/* TODO(shess): Prove that assertion, or extend the merge code to
+** merge tree fashion (like the prefix-searching code does).
+*/
+/* TODO(shess): OptLeavesReader and LeavesReader could probably be
+** merged with little or no loss of performance for LeavesReader.  The
+** merged code would need to handle >MERGE_COUNT segments, and would
+** also need to be able to optionally optimize away deletes.
+*/
+typedef struct OptLeavesReader {
+  /* Segment number, to order readers by age. */
+  int segment;
+  LeavesReader reader;
+} OptLeavesReader;
 
-  return insertTerms(v, *piDocid, pValues);
+static int optLeavesReaderAtEnd(OptLeavesReader *pReader){
+  return leavesReaderAtEnd(&pReader->reader);
+}
+static int optLeavesReaderTermBytes(OptLeavesReader *pReader){
+  return leavesReaderTermBytes(&pReader->reader);
+}
+static const char *optLeavesReaderData(OptLeavesReader *pReader){
+  return leavesReaderData(&pReader->reader);
+}
+static int optLeavesReaderDataBytes(OptLeavesReader *pReader){
+  return leavesReaderDataBytes(&pReader->reader);
+}
+static const char *optLeavesReaderTerm(OptLeavesReader *pReader){
+  return leavesReaderTerm(&pReader->reader);
+}
+static int optLeavesReaderStep(fulltext_vtab *v, OptLeavesReader *pReader){
+  return leavesReaderStep(v, &pReader->reader);
+}
+static int optLeavesReaderTermCmp(OptLeavesReader *lr1, OptLeavesReader *lr2){
+  return leavesReaderTermCmp(&lr1->reader, &lr2->reader);
+}
+/* Order by term ascending, segment ascending (oldest to newest), with
+** exhausted readers to the end.
+*/
+static int optLeavesReaderCmp(OptLeavesReader *lr1, OptLeavesReader *lr2){
+  int c = optLeavesReaderTermCmp(lr1, lr2);
+  if( c!=0 ) return c;
+  return lr1->segment-lr2->segment;
+}
+/* Bubble pLr[0] to appropriate place in pLr[1..nLr-1].  Assumes that
+** pLr[1..nLr-1] is already sorted.
+*/
+static void optLeavesReaderReorder(OptLeavesReader *pLr, int nLr){
+  while( nLr>1 && optLeavesReaderCmp(pLr, pLr+1)>0 ){
+    OptLeavesReader tmp = pLr[0];
+    pLr[0] = pLr[1];
+    pLr[1] = tmp;
+    nLr--;
+    pLr++;
+  }
 }
 
-/* Delete a row from the %_content table; add empty doclists for terms
-** to pendingTerms.
+/* optimize() helper function.  Put the readers in order and iterate
+** through them, merging doclists for matching terms into pWriter.
+** Returns SQLITE_OK on success, or the SQLite error code which
+** prevented success.
 */
-static int index_delete(fulltext_vtab *v, sqlite_int64 iRow){
-  int rc = initPendingTerms(v, iRow);
-  if( rc!=SQLITE_OK ) return rc;
+static int optimizeInternal(fulltext_vtab *v,
+                            OptLeavesReader *readers, int nReaders,
+                            LeafWriter *pWriter){
+  int i, rc = SQLITE_OK;
+  DataBuffer doclist, merged, tmp;
 
-  rc = deleteTerms(v, iRow);
-  if( rc!=SQLITE_OK ) return rc;
+  /* Order the readers. */
+  i = nReaders;
+  while( i-- > 0 ){
+    optLeavesReaderReorder(&readers[i], nReaders-i);
+  }
 
-  return content_delete(v, iRow);  /* execute an SQL DELETE */
-}
+  dataBufferInit(&doclist, LEAF_MAX);
+  dataBufferInit(&merged, LEAF_MAX);
 
-/* Update a row in the %_content table; add delete doclists to
-** pendingTerms for old terms not in the new data, add insert doclists
-** to pendingTerms for terms in the new data.
-*/
-static int index_update(fulltext_vtab *v, sqlite_int64 iRow,
-                        sqlite3_value **pValues){
-  int rc = initPendingTerms(v, iRow);
-  if( rc!=SQLITE_OK ) return rc;
+  /* Exhausted readers bubble to the end, so when the first reader is
+  ** at eof, all are at eof.
+  */
+  while( !optLeavesReaderAtEnd(&readers[0]) ){
 
-  /* Generate an empty doclist for each term that previously appeared in this
-   * row. */
-  rc = deleteTerms(v, iRow);
-  if( rc!=SQLITE_OK ) return rc;
+    /* Figure out how many readers share the next term. */
+    for(i=1; i 0 ){
+          dlrDestroy(&dlReaders[nReaders]);
+        }
+
+        /* Accumulated doclist to reader 0 for next pass. */
+        dlrInit(&dlReaders[0], DL_DEFAULT, doclist.pData, doclist.nData);
+      }
+
+      /* Destroy reader that was left in the pipeline. */
+      dlrDestroy(&dlReaders[0]);
+
+      /* Trim deletions from the doclist. */
+      dataBufferReset(&merged);
+      docListTrim(DL_DEFAULT, doclist.pData, doclist.nData,
+                  -1, DL_DEFAULT, &merged);
+    }
+
+    /* Only pass doclists with hits (skip if all hits deleted). */
+    if( merged.nData>0 ){
+      rc = leafWriterStep(v, pWriter,
+                          optLeavesReaderTerm(&readers[0]),
+                          optLeavesReaderTermBytes(&readers[0]),
+                          merged.pData, merged.nData);
+      if( rc!=SQLITE_OK ) goto err;
+    }
+
+    /* Step merged readers to next term and reorder. */
+    while( i-- > 0 ){
+      rc = optLeavesReaderStep(v, &readers[i]);
+      if( rc!=SQLITE_OK ) goto err;
+
+      optLeavesReaderReorder(&readers[i], nReaders-i);
+    }
+  }
+
+ err:
+  dataBufferDestroy(&doclist);
+  dataBufferDestroy(&merged);
+  return rc;
 }
 
-/*******************************************************************/
-/* InteriorWriter is used to collect terms and block references into
-** interior nodes in %_segments.  See commentary at top of file for
-** format.
+/* Implement optimize() function for FTS3.  optimize(t) merges all
+** segments in the fts index into a single segment.  't' is the magic
+** table-named column.
 */
+static void optimizeFunc(sqlite3_context *pContext,
+                         int argc, sqlite3_value **argv){
+  fulltext_cursor *pCursor;
+  if( argc>1 ){
+    sqlite3_result_error(pContext, "excess arguments to optimize()",-1);
+  }else if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
+            sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
+    sqlite3_result_error(pContext, "illegal first argument to optimize",-1);
+  }else{
+    fulltext_vtab *v;
+    int i, rc, iMaxLevel;
+    OptLeavesReader *readers;
+    int nReaders;
+    LeafWriter writer;
+    sqlite3_stmt *s;
 
-/* How large interior nodes can grow. */
-#define INTERIOR_MAX 2048
+    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
+    v = cursor_vtab(pCursor);
 
-/* Minimum number of terms per interior node (except the root). This
-** prevents large terms from making the tree too skinny - must be >0
-** so that the tree always makes progress.  Note that the min tree
-** fanout will be INTERIOR_MIN_TERMS+1.
-*/
-#define INTERIOR_MIN_TERMS 7
-#if INTERIOR_MIN_TERMS<1
-# error INTERIOR_MIN_TERMS must be greater than 0.
-#endif
+    /* Flush any buffered updates before optimizing. */
+    rc = flushPendingTerms(v);
+    if( rc!=SQLITE_OK ) goto err;
 
-/* ROOT_MAX controls how much data is stored inline in the segment
-** directory.
-*/
-/* TODO(shess) Push ROOT_MAX down to whoever is writing things.  It's
-** only here so that interiorWriterRootInfo() and leafWriterRootInfo()
-** can both see it, but if the caller passed it in, we wouldn't even
-** need a define.
-*/
-#define ROOT_MAX 1024
-#if ROOT_MAXterm, 0);
-    dataBufferReplace(&block->term, pTerm, nTerm);
+    /* Note that there will already be a segment at this position
+    ** until we call segdir_delete() on iMaxLevel.
+    */
+    leafWriterInit(iMaxLevel, 0, &writer);
 
-    n = fts3PutVarint(c, iHeight);
-    n += fts3PutVarint(c+n, iChildBlock);
-    dataBufferInit(&block->data, INTERIOR_MAX);
-    dataBufferReplace(&block->data, c, n);
-  }
-  return block;
-}
+    i = 0;
+    while( (rc = sqlite3_step(s))==SQLITE_ROW ){
+      sqlite_int64 iStart = sqlite3_column_int64(s, 0);
+      sqlite_int64 iEnd = sqlite3_column_int64(s, 1);
+      const char *pRootData = sqlite3_column_blob(s, 2);
+      int nRootData = sqlite3_column_bytes(s, 2);
 
-#ifndef NDEBUG
-/* Verify that the data is readable as an interior node. */
-static void interiorBlockValidate(InteriorBlock *pBlock){
-  const char *pData = pBlock->data.pData;
-  int nData = pBlock->data.nData;
-  int n, iDummy;
-  sqlite_int64 iBlockid;
+      assert( i0 );
-  assert( pData!=0 );
-  assert( pData+nData>pData );
+      readers[i].segment = i;
+      i++;
+    }
 
-  /* Must lead with height of node as a varint(n), n>0 */
-  n = fts3GetVarint32(pData, &iDummy);
-  assert( n>0 );
-  assert( iDummy>0 );
-  assert( n0 );
-  assert( n<=nData );
-  pData += n;
-  nData -= n;
+    while( i-- > 0 ){
+      leavesReaderDestroy(&readers[i].reader);
+    }
+    sqlite3_free(readers);
 
-  /* Zero or more terms of positive length */
-  if( nData!=0 ){
-    /* First term is not delta-encoded. */
-    n = fts3GetVarint32(pData, &iDummy);
-    assert( n>0 );
-    assert( iDummy>0 );
-    assert( n+iDummy>0);
-    assert( n+iDummy<=nData );
-    pData += n+iDummy;
-    nData -= n+iDummy;
+    /* If we've successfully gotten to here, delete the old segments
+    ** and flush the interior structure of the new segment.
+    */
+    if( rc==SQLITE_OK ){
+      for( i=0; i<=iMaxLevel; i++ ){
+        rc = segdir_delete(v, i);
+        if( rc!=SQLITE_OK ) break;
+      }
 
-    /* Following terms delta-encoded. */
-    while( nData!=0 ){
-      /* Length of shared prefix. */
-      n = fts3GetVarint32(pData, &iDummy);
-      assert( n>0 );
-      assert( iDummy>=0 );
-      assert( n0 );
-      assert( iDummy>0 );
-      assert( n+iDummy>0);
-      assert( n+iDummy<=nData );
-      pData += n+iDummy;
-      nData -= n+iDummy;
+    leafWriterDestroy(&writer);
+
+    if( rc!=SQLITE_OK ) goto err;
+
+    sqlite3_result_text(pContext, "Index optimized", -1, SQLITE_STATIC);
+    return;
+
+    /* TODO(shess): Error-handling needs to be improved along the
+    ** lines of the dump_ functions.
+    */
+ err:
+    {
+      char buf[512];
+      sqlite3_snprintf(sizeof(buf), buf, "Error in optimize: %s",
+                       sqlite3_errmsg(sqlite3_context_db_handle(pContext)));
+      sqlite3_result_error(pContext, buf, -1);
     }
   }
 }
-#define ASSERT_VALID_INTERIOR_BLOCK(x) interiorBlockValidate(x)
-#else
-#define ASSERT_VALID_INTERIOR_BLOCK(x) assert( 1 )
-#endif
 
-typedef struct InteriorWriter {
-  int iHeight;                   /* from 0 at leaves. */
-  InteriorBlock *first, *last;
-  struct InteriorWriter *parentWriter;
+#ifdef SQLITE_TEST
+/* Generate an error of the form ": ".  If msg is NULL,
+** pull the error from the context's db handle.
+*/
+static void generateError(sqlite3_context *pContext,
+                          const char *prefix, const char *msg){
+  char buf[512];
+  if( msg==NULL ) msg = sqlite3_errmsg(sqlite3_context_db_handle(pContext));
+  sqlite3_snprintf(sizeof(buf), buf, "%s: %s", prefix, msg);
+  sqlite3_result_error(pContext, buf, -1);
+}
+
+/* Helper function to collect the set of terms in the segment into
+** pTerms.  The segment is defined by the leaf nodes between
+** iStartBlockid and iEndBlockid, inclusive, or by the contents of
+** pRootData if iStartBlockid is 0 (in which case the entire segment
+** fit in a leaf).
+*/
+static int collectSegmentTerms(fulltext_vtab *v, sqlite3_stmt *s,
+                               fts3Hash *pTerms){
+  const sqlite_int64 iStartBlockid = sqlite3_column_int64(s, 0);
+  const sqlite_int64 iEndBlockid = sqlite3_column_int64(s, 1);
+  const char *pRootData = sqlite3_column_blob(s, 2);
+  const int nRootData = sqlite3_column_bytes(s, 2);
+  LeavesReader reader;
+  int rc = leavesReaderInit(v, 0, iStartBlockid, iEndBlockid,
+                            pRootData, nRootData, &reader);
+  if( rc!=SQLITE_OK ) return rc;
 
-  DataBuffer term;               /* Last term written to block "last". */
-  sqlite_int64 iOpeningChildBlock; /* First child block in block "last". */
-#ifndef NDEBUG
-  sqlite_int64 iLastChildBlock;  /* for consistency checks. */
-#endif
-} InteriorWriter;
+  while( rc==SQLITE_OK && !leavesReaderAtEnd(&reader) ){
+    const char *pTerm = leavesReaderTerm(&reader);
+    const int nTerm = leavesReaderTermBytes(&reader);
+    void *oldValue = sqlite3Fts3HashFind(pTerms, pTerm, nTerm);
+    void *newValue = (void *)((char *)oldValue+1);
 
-/* Initialize an interior node where pTerm[nTerm] marks the leftmost
-** term in the tree.  iChildBlock is the leftmost child block at the
-** next level down the tree.
-*/
-static void interiorWriterInit(int iHeight, const char *pTerm, int nTerm,
-                               sqlite_int64 iChildBlock,
-                               InteriorWriter *pWriter){
-  InteriorBlock *block;
-  assert( iHeight>0 );
-  CLEAR(pWriter);
+    /* From the comment before sqlite3Fts3HashInsert in fts3_hash.c,
+    ** the data value passed is returned in case of malloc failure.
+    */
+    if( newValue==sqlite3Fts3HashInsert(pTerms, pTerm, nTerm, newValue) ){
+      rc = SQLITE_NOMEM;
+    }else{
+      rc = leavesReaderStep(v, &reader);
+    }
+  }
 
-  pWriter->iHeight = iHeight;
-  pWriter->iOpeningChildBlock = iChildBlock;
-#ifndef NDEBUG
-  pWriter->iLastChildBlock = iChildBlock;
-#endif
-  block = interiorBlockNew(iHeight, iChildBlock, pTerm, nTerm);
-  pWriter->last = pWriter->first = block;
-  ASSERT_VALID_INTERIOR_BLOCK(pWriter->last);
-  dataBufferInit(&pWriter->term, 0);
+  leavesReaderDestroy(&reader);
+  return rc;
 }
 
-/* Append the child node rooted at iChildBlock to the interior node,
-** with pTerm[nTerm] as the leftmost term in iChildBlock's subtree.
-*/
-static void interiorWriterAppend(InteriorWriter *pWriter,
-                                 const char *pTerm, int nTerm,
-                                 sqlite_int64 iChildBlock){
-  char c[VARINT_MAX+VARINT_MAX];
-  int n, nPrefix = 0;
-
-  ASSERT_VALID_INTERIOR_BLOCK(pWriter->last);
+/* Helper function to build the result string for dump_terms(). */
+static int generateTermsResult(sqlite3_context *pContext, fts3Hash *pTerms){
+  int iTerm, nTerms, nResultBytes, iByte;
+  char *result;
+  TermData *pData;
+  fts3HashElem *e;
 
-  /* The first term written into an interior node is actually
-  ** associated with the second child added (the first child was added
-  ** in interiorWriterInit, or in the if clause at the bottom of this
-  ** function).  That term gets encoded straight up, with nPrefix left
-  ** at 0.
+  /* Iterate pTerms to generate an array of terms in pData for
+  ** sorting.
   */
-  if( pWriter->term.nData==0 ){
-    n = fts3PutVarint(c, nTerm);
-  }else{
-    while( nPrefixterm.nData &&
-           pTerm[nPrefix]==pWriter->term.pData[nPrefix] ){
-      nPrefix++;
-    }
+  nTerms = fts3HashCount(pTerms);
+  assert( nTerms>0 );
+  pData = sqlite3_malloc(nTerms*sizeof(TermData));
+  if( pData==NULL ) return SQLITE_NOMEM;
 
-    n = fts3PutVarint(c, nPrefix);
-    n += fts3PutVarint(c+n, nTerm-nPrefix);
+  nResultBytes = 0;
+  for(iTerm = 0, e = fts3HashFirst(pTerms); e; iTerm++, e = fts3HashNext(e)){
+    nResultBytes += fts3HashKeysize(e)+1;   /* Term plus trailing space */
+    assert( iTermiLastChildBlock++;
-#endif
-  assert( pWriter->iLastChildBlock==iChildBlock );
-
-  /* Overflow to a new block if the new term makes the current block
-  ** too big, and the current block already has enough terms.
-  */
-  if( pWriter->last->data.nData+n+nTerm-nPrefix>INTERIOR_MAX &&
-      iChildBlock-pWriter->iOpeningChildBlock>INTERIOR_MIN_TERMS ){
-    pWriter->last->next = interiorBlockNew(pWriter->iHeight, iChildBlock,
-                                           pTerm, nTerm);
-    pWriter->last = pWriter->last->next;
-    pWriter->iOpeningChildBlock = iChildBlock;
-    dataBufferReset(&pWriter->term);
-  }else{
-    dataBufferAppend2(&pWriter->last->data, c, n,
-                      pTerm+nPrefix, nTerm-nPrefix);
-    dataBufferReplace(&pWriter->term, pTerm, nTerm);
+  assert( nResultBytes>0 );   /* nTerms>0, nResultsBytes must be, too. */
+  result = sqlite3_malloc(nResultBytes);
+  if( result==NULL ){
+    sqlite3_free(pData);
+    return SQLITE_NOMEM;
   }
-  ASSERT_VALID_INTERIOR_BLOCK(pWriter->last);
-}
 
-/* Free the space used by pWriter, including the linked-list of
-** InteriorBlocks, and parentWriter, if present.
-*/
-static int interiorWriterDestroy(InteriorWriter *pWriter){
-  InteriorBlock *block = pWriter->first;
+  if( nTerms>1 ) qsort(pData, nTerms, sizeof(*pData), termDataCmp);
 
-  while( block!=NULL ){
-    InteriorBlock *b = block;
-    block = block->next;
-    dataBufferDestroy(&b->term);
-    dataBufferDestroy(&b->data);
-    sqlite3_free(b);
-  }
-  if( pWriter->parentWriter!=NULL ){
-    interiorWriterDestroy(pWriter->parentWriter);
-    sqlite3_free(pWriter->parentWriter);
+  /* Read the terms in order to build the result. */
+  iByte = 0;
+  for(iTerm=0; iTermterm);
-  SCRAMBLE(pWriter);
+  assert( iByte==nResultBytes );
+  assert( result[nResultBytes-1]==' ' );
+  result[nResultBytes-1] = '\0';
+
+  /* Passes away ownership of result. */
+  sqlite3_result_text(pContext, result, nResultBytes-1, sqlite3_free);
+  sqlite3_free(pData);
   return SQLITE_OK;
 }
 
-/* If pWriter can fit entirely in ROOT_MAX, return it as the root info
-** directly, leaving *piEndBlockid unchanged.  Otherwise, flush
-** pWriter to %_segments, building a new layer of interior nodes, and
-** recursively ask for their root into.
+/* Implements dump_terms() for use in inspecting the fts3 index from
+** tests.  TEXT result containing the ordered list of terms joined by
+** spaces.  dump_terms(t, level, idx) dumps the terms for the segment
+** specified by level, idx (in %_segdir), while dump_terms(t) dumps
+** all terms in the index.  In both cases t is the fts table's magic
+** table-named column.
 */
-static int interiorWriterRootInfo(fulltext_vtab *v, InteriorWriter *pWriter,
-                                  char **ppRootInfo, int *pnRootInfo,
-                                  sqlite_int64 *piEndBlockid){
-  InteriorBlock *block = pWriter->first;
-  sqlite_int64 iBlockid = 0;
-  int rc;
+static void dumpTermsFunc(
+  sqlite3_context *pContext,
+  int argc, sqlite3_value **argv
+){
+  fulltext_cursor *pCursor;
+  if( argc!=3 && argc!=1 ){
+    generateError(pContext, "dump_terms", "incorrect arguments");
+  }else if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
+            sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
+    generateError(pContext, "dump_terms", "illegal first argument");
+  }else{
+    fulltext_vtab *v;
+    fts3Hash terms;
+    sqlite3_stmt *s = NULL;
+    int rc;
 
-  /* If we can fit the segment inline */
-  if( block==pWriter->last && block->data.nDatadata.pData;
-    *pnRootInfo = block->data.nData;
-    return SQLITE_OK;
-  }
+    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
+    v = cursor_vtab(pCursor);
 
-  /* Flush the first block to %_segments, and create a new level of
-  ** interior node.
-  */
-  ASSERT_VALID_INTERIOR_BLOCK(block);
-  rc = block_insert(v, block->data.pData, block->data.nData, &iBlockid);
-  if( rc!=SQLITE_OK ) return rc;
-  *piEndBlockid = iBlockid;
+    /* If passed only the cursor column, get all segments.  Otherwise
+    ** get the segment described by the following two arguments.
+    */
+    if( argc==1 ){
+      rc = sql_get_statement(v, SEGDIR_SELECT_ALL_STMT, &s);
+    }else{
+      rc = sql_get_statement(v, SEGDIR_SELECT_SEGMENT_STMT, &s);
+      if( rc==SQLITE_OK ){
+        rc = sqlite3_bind_int(s, 1, sqlite3_value_int(argv[1]));
+        if( rc==SQLITE_OK ){
+          rc = sqlite3_bind_int(s, 2, sqlite3_value_int(argv[2]));
+        }
+      }
+    }
 
-  pWriter->parentWriter = sqlite3_malloc(sizeof(*pWriter->parentWriter));
-  interiorWriterInit(pWriter->iHeight+1,
-                     block->term.pData, block->term.nData,
-                     iBlockid, pWriter->parentWriter);
+    if( rc!=SQLITE_OK ){
+      generateError(pContext, "dump_terms", NULL);
+      return;
+    }
 
-  /* Flush additional blocks and append to the higher interior
-  ** node.
-  */
-  for(block=block->next; block!=NULL; block=block->next){
-    ASSERT_VALID_INTERIOR_BLOCK(block);
-    rc = block_insert(v, block->data.pData, block->data.nData, &iBlockid);
-    if( rc!=SQLITE_OK ) return rc;
-    *piEndBlockid = iBlockid;
+    /* Collect the terms for each segment. */
+    sqlite3Fts3HashInit(&terms, FTS3_HASH_STRING, 1);
+    while( (rc = sqlite3_step(s))==SQLITE_ROW ){
+      rc = collectSegmentTerms(v, s, &terms);
+      if( rc!=SQLITE_OK ) break;
+    }
 
-    interiorWriterAppend(pWriter->parentWriter,
-                         block->term.pData, block->term.nData, iBlockid);
+    if( rc!=SQLITE_DONE ){
+      sqlite3_reset(s);
+      generateError(pContext, "dump_terms", NULL);
+    }else{
+      const int nTerms = fts3HashCount(&terms);
+      if( nTerms>0 ){
+        rc = generateTermsResult(pContext, &terms);
+        if( rc==SQLITE_NOMEM ){
+          generateError(pContext, "dump_terms", "out of memory");
+        }else{
+          assert( rc==SQLITE_OK );
+        }
+      }else if( argc==3 ){
+        /* The specific segment asked for could not be found. */
+        generateError(pContext, "dump_terms", "segment not found");
+      }else{
+        /* No segments found. */
+        /* TODO(shess): It should be impossible to reach this.  This
+        ** case can only happen for an empty table, in which case
+        ** SQLite has no rows to call this function on.
+        */
+        sqlite3_result_null(pContext);
+      }
+    }
+    sqlite3Fts3HashClear(&terms);
   }
-
-  /* Parent node gets the chance to be the root. */
-  return interiorWriterRootInfo(v, pWriter->parentWriter,
-                                ppRootInfo, pnRootInfo, piEndBlockid);
 }
 
-/****************************************************************/
-/* InteriorReader is used to read off the data from an interior node
-** (see comment at top of file for the format).
+/* Expand the DL_DEFAULT doclist in pData into a text result in
+** pContext.
 */
-typedef struct InteriorReader {
-  const char *pData;
-  int nData;
+static void createDoclistResult(sqlite3_context *pContext,
+                                const char *pData, int nData){
+  DataBuffer dump;
+  DLReader dlReader;
 
-  DataBuffer term;          /* previous term, for decoding term delta. */
+  assert( pData!=NULL && nData>0 );
 
-  sqlite_int64 iBlockid;
-} InteriorReader;
+  dataBufferInit(&dump, 0);
+  dlrInit(&dlReader, DL_DEFAULT, pData, nData);
+  for( ; !dlrAtEnd(&dlReader); dlrStep(&dlReader) ){
+    char buf[256];
+    PLReader plReader;
 
-static void interiorReaderDestroy(InteriorReader *pReader){
-  dataBufferDestroy(&pReader->term);
-  SCRAMBLE(pReader);
+    plrInit(&plReader, &dlReader);
+    if( DL_DEFAULT==DL_DOCIDS || plrAtEnd(&plReader) ){
+      sqlite3_snprintf(sizeof(buf), buf, "[%lld] ", dlrDocid(&dlReader));
+      dataBufferAppend(&dump, buf, strlen(buf));
+    }else{
+      int iColumn = plrColumn(&plReader);
+
+      sqlite3_snprintf(sizeof(buf), buf, "[%lld %d[",
+                       dlrDocid(&dlReader), iColumn);
+      dataBufferAppend(&dump, buf, strlen(buf));
+
+      for( ; !plrAtEnd(&plReader); plrStep(&plReader) ){
+        if( plrColumn(&plReader)!=iColumn ){
+          iColumn = plrColumn(&plReader);
+          sqlite3_snprintf(sizeof(buf), buf, "] %d[", iColumn);
+          assert( dump.nData>0 );
+          dump.nData--;                     /* Overwrite trailing space. */
+          assert( dump.pData[dump.nData]==' ');
+          dataBufferAppend(&dump, buf, strlen(buf));
+        }
+        if( DL_DEFAULT==DL_POSITIONS_OFFSETS ){
+          sqlite3_snprintf(sizeof(buf), buf, "%d,%d,%d ",
+                           plrPosition(&plReader),
+                           plrStartOffset(&plReader), plrEndOffset(&plReader));
+        }else if( DL_DEFAULT==DL_POSITIONS ){
+          sqlite3_snprintf(sizeof(buf), buf, "%d ", plrPosition(&plReader));
+        }else{
+          assert( NULL=="Unhandled DL_DEFAULT value");
+        }
+        dataBufferAppend(&dump, buf, strlen(buf));
+      }
+      plrDestroy(&plReader);
+
+      assert( dump.nData>0 );
+      dump.nData--;                     /* Overwrite trailing space. */
+      assert( dump.pData[dump.nData]==' ');
+      dataBufferAppend(&dump, "]] ", 3);
+    }
+  }
+  dlrDestroy(&dlReader);
+
+  assert( dump.nData>0 );
+  dump.nData--;                     /* Overwrite trailing space. */
+  assert( dump.pData[dump.nData]==' ');
+  dump.pData[dump.nData] = '\0';
+  assert( dump.nData>0 );
+
+  /* Passes ownership of dump's buffer to pContext. */
+  sqlite3_result_text(pContext, dump.pData, dump.nData, sqlite3_free);
+  dump.pData = NULL;
+  dump.nData = dump.nCapacity = 0;
 }
 
-/* TODO(shess) The assertions are great, but what if we're in NDEBUG
-** and the blob is empty or otherwise contains suspect data?
+/* Implements dump_doclist() for use in inspecting the fts3 index from
+** tests.  TEXT result containing a string representation of the
+** doclist for the indicated term.  dump_doclist(t, term, level, idx)
+** dumps the doclist for term from the segment specified by level, idx
+** (in %_segdir), while dump_doclist(t, term) dumps the logical
+** doclist for the term across all segments.  The per-segment doclist
+** can contain deletions, while the full-index doclist will not
+** (deletions are omitted).
+**
+** Result formats differ with the setting of DL_DEFAULTS.  Examples:
+**
+** DL_DOCIDS: [1] [3] [7]
+** DL_POSITIONS: [1 0[0 4] 1[17]] [3 1[5]]
+** DL_POSITIONS_OFFSETS: [1 0[0,0,3 4,23,26] 1[17,102,105]] [3 1[5,20,23]]
+**
+** In each case the number after the outer '[' is the docid.  In the
+** latter two cases, the number before the inner '[' is the column
+** associated with the values within.  For DL_POSITIONS the numbers
+** within are the positions, for DL_POSITIONS_OFFSETS they are the
+** position, the start offset, and the end offset.
 */
-static void interiorReaderInit(const char *pData, int nData,
-                               InteriorReader *pReader){
-  int n, nTerm;
+static void dumpDoclistFunc(
+  sqlite3_context *pContext,
+  int argc, sqlite3_value **argv
+){
+  fulltext_cursor *pCursor;
+  if( argc!=2 && argc!=4 ){
+    generateError(pContext, "dump_doclist", "incorrect arguments");
+  }else if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
+            sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
+    generateError(pContext, "dump_doclist", "illegal first argument");
+  }else if( sqlite3_value_text(argv[1])==NULL ||
+            sqlite3_value_text(argv[1])[0]=='\0' ){
+    generateError(pContext, "dump_doclist", "empty second argument");
+  }else{
+    const char *pTerm = (const char *)sqlite3_value_text(argv[1]);
+    const int nTerm = strlen(pTerm);
+    fulltext_vtab *v;
+    int rc;
+    DataBuffer doclist;
 
-  /* Require at least the leading flag byte */
-  assert( nData>0 );
-  assert( pData[0]!='\0' );
+    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
+    v = cursor_vtab(pCursor);
 
-  CLEAR(pReader);
+    dataBufferInit(&doclist, 0);
 
-  /* Decode the base blockid, and set the cursor to the first term. */
-  n = fts3GetVarint(pData+1, &pReader->iBlockid);
-  assert( 1+n<=nData );
-  pReader->pData = pData+1+n;
-  pReader->nData = nData-(1+n);
+    /* termSelect() yields the same logical doclist that queries are
+    ** run against.
+    */
+    if( argc==2 ){
+      rc = termSelect(v, v->nColumn, pTerm, nTerm, 0, DL_DEFAULT, &doclist);
+    }else{
+      sqlite3_stmt *s = NULL;
 
-  /* A single-child interior node (such as when a leaf node was too
-  ** large for the segment directory) won't have any terms.
-  ** Otherwise, decode the first term.
-  */
-  if( pReader->nData==0 ){
-    dataBufferInit(&pReader->term, 0);
-  }else{
-    n = fts3GetVarint32(pReader->pData, &nTerm);
-    dataBufferInit(&pReader->term, nTerm);
-    dataBufferReplace(&pReader->term, pReader->pData+n, nTerm);
-    assert( n+nTerm<=pReader->nData );
-    pReader->pData += n+nTerm;
-    pReader->nData -= n+nTerm;
+      /* Get our specific segment's information. */
+      rc = sql_get_statement(v, SEGDIR_SELECT_SEGMENT_STMT, &s);
+      if( rc==SQLITE_OK ){
+        rc = sqlite3_bind_int(s, 1, sqlite3_value_int(argv[2]));
+        if( rc==SQLITE_OK ){
+          rc = sqlite3_bind_int(s, 2, sqlite3_value_int(argv[3]));
+        }
+      }
+
+      if( rc==SQLITE_OK ){
+        rc = sqlite3_step(s);
+
+        if( rc==SQLITE_DONE ){
+          dataBufferDestroy(&doclist);
+          generateError(pContext, "dump_doclist", "segment not found");
+          return;
+        }
+
+        /* Found a segment, load it into doclist. */
+        if( rc==SQLITE_ROW ){
+          const sqlite_int64 iLeavesEnd = sqlite3_column_int64(s, 1);
+          const char *pData = sqlite3_column_blob(s, 2);
+          const int nData = sqlite3_column_bytes(s, 2);
+
+          /* loadSegment() is used by termSelect() to load each
+          ** segment's data.
+          */
+          rc = loadSegment(v, pData, nData, iLeavesEnd, pTerm, nTerm, 0,
+                           &doclist);
+          if( rc==SQLITE_OK ){
+            rc = sqlite3_step(s);
+
+            /* Should not have more than one matching segment. */
+            if( rc!=SQLITE_DONE ){
+              sqlite3_reset(s);
+              dataBufferDestroy(&doclist);
+              generateError(pContext, "dump_doclist", "invalid segdir");
+              return;
+            }
+            rc = SQLITE_OK;
+          }
+        }
+      }
+
+      sqlite3_reset(s);
+    }
+
+    if( rc==SQLITE_OK ){
+      if( doclist.nData>0 ){
+        createDoclistResult(pContext, doclist.pData, doclist.nData);
+      }else{
+        /* TODO(shess): This can happen if the term is not present, or
+        ** if all instances of the term have been deleted and this is
+        ** an all-index dump.  It may be interesting to distinguish
+        ** these cases.
+        */
+        sqlite3_result_text(pContext, "", 0, SQLITE_STATIC);
+      }
+    }else if( rc==SQLITE_NOMEM ){
+      /* Handle out-of-memory cases specially because if they are
+      ** generated in fts3 code they may not be reflected in the db
+      ** handle.
+      */
+      /* TODO(shess): Handle this more comprehensively.
+      ** sqlite3ErrStr() has what I need, but is internal.
+      */
+      generateError(pContext, "dump_doclist", "out of memory");
+    }else{
+      generateError(pContext, "dump_doclist", NULL);
+    }
+
+    dataBufferDestroy(&doclist);
   }
 }
+#endif
 
-static int interiorReaderAtEnd(InteriorReader *pReader){
-  return pReader->term.nData==0;
+/*
+** This routine implements the xFindFunction method for the FTS3
+** virtual table.
+*/
+static int fulltextFindFunction(
+  sqlite3_vtab *pVtab,
+  int nArg,
+  const char *zName,
+  void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
+  void **ppArg
+){
+  if( strcmp(zName,"snippet")==0 ){
+    *pxFunc = snippetFunc;
+    return 1;
+  }else if( strcmp(zName,"offsets")==0 ){
+    *pxFunc = snippetOffsetsFunc;
+    return 1;
+  }else if( strcmp(zName,"optimize")==0 ){
+    *pxFunc = optimizeFunc;
+    return 1;
+#ifdef SQLITE_TEST
+    /* NOTE(shess): These functions are present only for testing
+    ** purposes.  No particular effort is made to optimize their
+    ** execution or how they build their results.
+    */
+  }else if( strcmp(zName,"dump_terms")==0 ){
+    /* fprintf(stderr, "Found dump_terms\n"); */
+    *pxFunc = dumpTermsFunc;
+    return 1;
+  }else if( strcmp(zName,"dump_doclist")==0 ){
+    /* fprintf(stderr, "Found dump_doclist\n"); */
+    *pxFunc = dumpDoclistFunc;
+    return 1;
+#endif
+  }
+  return 0;
 }
 
-static sqlite_int64 interiorReaderCurrentBlockid(InteriorReader *pReader){
-  return pReader->iBlockid;
+/*
+** Rename an fts3 table.
+*/
+static int fulltextRename(
+  sqlite3_vtab *pVtab,
+  const char *zName
+){
+  fulltext_vtab *p = (fulltext_vtab *)pVtab;
+  int rc = SQLITE_NOMEM;
+  char *zSql = sqlite3_mprintf(
+    "ALTER TABLE %Q.'%q_content'  RENAME TO '%q_content';"
+    "ALTER TABLE %Q.'%q_segments' RENAME TO '%q_segments';"
+    "ALTER TABLE %Q.'%q_segdir'   RENAME TO '%q_segdir';"
+    , p->zDb, p->zName, zName 
+    , p->zDb, p->zName, zName 
+    , p->zDb, p->zName, zName
+  );
+  if( zSql ){
+    rc = sqlite3_exec(p->db, zSql, 0, 0, 0);
+    sqlite3_free(zSql);
+  }
+  return rc;
 }
 
-static int interiorReaderTermBytes(InteriorReader *pReader){
-  assert( !interiorReaderAtEnd(pReader) );
-  return pReader->term.nData;
-}
-static const char *interiorReaderTerm(InteriorReader *pReader){
-  assert( !interiorReaderAtEnd(pReader) );
-  return pReader->term.pData;
+static const sqlite3_module fts3Module = {
+  /* iVersion      */ 0,
+  /* xCreate       */ fulltextCreate,
+  /* xConnect      */ fulltextConnect,
+  /* xBestIndex    */ fulltextBestIndex,
+  /* xDisconnect   */ fulltextDisconnect,
+  /* xDestroy      */ fulltextDestroy,
+  /* xOpen         */ fulltextOpen,
+  /* xClose        */ fulltextClose,
+  /* xFilter       */ fulltextFilter,
+  /* xNext         */ fulltextNext,
+  /* xEof          */ fulltextEof,
+  /* xColumn       */ fulltextColumn,
+  /* xRowid        */ fulltextRowid,
+  /* xUpdate       */ fulltextUpdate,
+  /* xBegin        */ fulltextBegin,
+  /* xSync         */ fulltextSync,
+  /* xCommit       */ fulltextCommit,
+  /* xRollback     */ fulltextRollback,
+  /* xFindFunction */ fulltextFindFunction,
+  /* xRename */       fulltextRename,
+};
+
+static void hashDestroy(void *p){
+  fts3Hash *pHash = (fts3Hash *)p;
+  sqlite3Fts3HashClear(pHash);
+  sqlite3_free(pHash);
 }
 
-/* Step forward to the next term in the node. */
-static void interiorReaderStep(InteriorReader *pReader){
-  assert( !interiorReaderAtEnd(pReader) );
+/*
+** The fts3 built-in tokenizers - "simple" and "porter" - are implemented
+** in files fts3_tokenizer1.c and fts3_porter.c respectively. The following
+** two forward declarations are for functions declared in these files
+** used to retrieve the respective implementations.
+**
+** Calling sqlite3Fts3SimpleTokenizerModule() sets the value pointed
+** to by the argument to point a the "simple" tokenizer implementation.
+** Function ...PorterTokenizerModule() sets *pModule to point to the
+** porter tokenizer/stemmer implementation.
+*/
+SQLITE_PRIVATE void sqlite3Fts3SimpleTokenizerModule(sqlite3_tokenizer_module const**ppModule);
+SQLITE_PRIVATE void sqlite3Fts3PorterTokenizerModule(sqlite3_tokenizer_module const**ppModule);
+SQLITE_PRIVATE void sqlite3Fts3IcuTokenizerModule(sqlite3_tokenizer_module const**ppModule);
+
+SQLITE_PRIVATE int sqlite3Fts3InitHashTable(sqlite3 *, fts3Hash *, const char *);
+
+/*
+** Initialise the fts3 extension. If this extension is built as part
+** of the sqlite library, then this function is called directly by
+** SQLite. If fts3 is built as a dynamically loadable extension, this
+** function is called by the sqlite3_extension_init() entry point.
+*/
+SQLITE_PRIVATE int sqlite3Fts3Init(sqlite3 *db){
+  int rc = SQLITE_OK;
+  fts3Hash *pHash = 0;
+  const sqlite3_tokenizer_module *pSimple = 0;
+  const sqlite3_tokenizer_module *pPorter = 0;
+  const sqlite3_tokenizer_module *pIcu = 0;
+
+  sqlite3Fts3SimpleTokenizerModule(&pSimple);
+  sqlite3Fts3PorterTokenizerModule(&pPorter);
+#ifdef SQLITE_ENABLE_ICU
+  sqlite3Fts3IcuTokenizerModule(&pIcu);
+#endif
 
-  /* If the last term has been read, signal eof, else construct the
-  ** next term.
-  */
-  if( pReader->nData==0 ){
-    dataBufferReset(&pReader->term);
+  /* Allocate and initialise the hash-table used to store tokenizers. */
+  pHash = sqlite3_malloc(sizeof(fts3Hash));
+  if( !pHash ){
+    rc = SQLITE_NOMEM;
   }else{
-    int n, nPrefix, nSuffix;
-
-    n = fts3GetVarint32(pReader->pData, &nPrefix);
-    n += fts3GetVarint32(pReader->pData+n, &nSuffix);
-
-    /* Truncate the current term and append suffix data. */
-    pReader->term.nData = nPrefix;
-    dataBufferAppend(&pReader->term, pReader->pData+n, nSuffix);
+    sqlite3Fts3HashInit(pHash, FTS3_HASH_STRING, 1);
+  }
 
-    assert( n+nSuffix<=pReader->nData );
-    pReader->pData += n+nSuffix;
-    pReader->nData -= n+nSuffix;
+  /* Load the built-in tokenizers into the hash table */
+  if( rc==SQLITE_OK ){
+    if( sqlite3Fts3HashInsert(pHash, "simple", 7, (void *)pSimple)
+     || sqlite3Fts3HashInsert(pHash, "porter", 7, (void *)pPorter) 
+     || (pIcu && sqlite3Fts3HashInsert(pHash, "icu", 4, (void *)pIcu))
+    ){
+      rc = SQLITE_NOMEM;
+    }
   }
-  pReader->iBlockid++;
-}
 
-/* Compare the current term to pTerm[nTerm], returning strcmp-style
-** results.  If isPrefix, equality means equal through nTerm bytes.
-*/
-static int interiorReaderTermCmp(InteriorReader *pReader,
-                                 const char *pTerm, int nTerm, int isPrefix){
-  const char *pReaderTerm = interiorReaderTerm(pReader);
-  int nReaderTerm = interiorReaderTermBytes(pReader);
-  int c, n = nReaderTerm0 ) return -1;
-    if( nTerm>0 ) return 1;
-    return 0;
+  /* An error has occured. Delete the hash table and return the error code. */
+  assert( rc!=SQLITE_OK );
+  if( pHash ){
+    sqlite3Fts3HashClear(pHash);
+    sqlite3_free(pHash);
   }
+  return rc;
+}
 
-  c = memcmp(pReaderTerm, pTerm, n);
-  if( c!=0 ) return c;
-  if( isPrefix && n==nTerm ) return 0;
-  return nReaderTerm - nTerm;
+#if !SQLITE_CORE
+SQLITE_API int sqlite3_extension_init(
+  sqlite3 *db, 
+  char **pzErrMsg,
+  const sqlite3_api_routines *pApi
+){
+  SQLITE_EXTENSION_INIT2(pApi)
+  return sqlite3Fts3Init(db);
 }
+#endif
 
-/****************************************************************/
-/* LeafWriter is used to collect terms and associated doclist data
-** into leaf blocks in %_segments (see top of file for format info).
-** Expected usage is:
+#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
+
+/************** End of fts3.c ************************************************/
+/************** Begin file fts3_hash.c ***************************************/
+/*
+** 2001 September 22
 **
-** LeafWriter writer;
-** leafWriterInit(0, 0, &writer);
-** while( sorted_terms_left_to_process ){
-**   // data is doclist data for that term.
-**   rc = leafWriterStep(v, &writer, pTerm, nTerm, pData, nData);
-**   if( rc!=SQLITE_OK ) goto err;
-** }
-** rc = leafWriterFinalize(v, &writer);
-**err:
-** leafWriterDestroy(&writer);
-** return rc;
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
 **
-** leafWriterStep() may write a collected leaf out to %_segments.
-** leafWriterFinalize() finishes writing any buffered data and stores
-** a root node in %_segdir.  leafWriterDestroy() frees all buffers and
-** InteriorWriters allocated as part of writing this segment.
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
 **
-** TODO(shess) Document leafWriterStepMerge().
+*************************************************************************
+** This is the implementation of generic hash-tables used in SQLite.
+** We've modified it slightly to serve as a standalone hash table
+** implementation for the full-text indexing module.
 */
 
-/* Put terms with data this big in their own block. */
-#define STANDALONE_MIN 1024
-
-/* Keep leaf blocks below this size. */
-#define LEAF_MAX 2048
-
-typedef struct LeafWriter {
-  int iLevel;
-  int idx;
-  sqlite_int64 iStartBlockid;     /* needed to create the root info */
-  sqlite_int64 iEndBlockid;       /* when we're done writing. */
-
-  DataBuffer term;                /* previous encoded term */
-  DataBuffer data;                /* encoding buffer */
-
-  /* bytes of first term in the current node which distinguishes that
-  ** term from the last term of the previous node.
-  */
-  int nTermDistinct;
-
-  InteriorWriter parentWriter;    /* if we overflow */
-  int has_parent;
-} LeafWriter;
+/*
+** The code in this file is only compiled if:
+**
+**     * The FTS3 module is being built as an extension
+**       (in which case SQLITE_CORE is not defined), or
+**
+**     * The FTS3 module is being built into the core of
+**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
+*/
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
 
-static void leafWriterInit(int iLevel, int idx, LeafWriter *pWriter){
-  CLEAR(pWriter);
-  pWriter->iLevel = iLevel;
-  pWriter->idx = idx;
 
-  dataBufferInit(&pWriter->term, 32);
 
-  /* Start out with a reasonably sized block, though it can grow. */
-  dataBufferInit(&pWriter->data, LEAF_MAX);
+/*
+** Malloc and Free functions
+*/
+static void *fts3HashMalloc(int n){
+  void *p = sqlite3_malloc(n);
+  if( p ){
+    memset(p, 0, n);
+  }
+  return p;
+}
+static void fts3HashFree(void *p){
+  sqlite3_free(p);
 }
 
-#ifndef NDEBUG
-/* Verify that the data is readable as a leaf node. */
-static void leafNodeValidate(const char *pData, int nData){
-  int n, iDummy;
-
-  if( nData==0 ) return;
-  assert( nData>0 );
-  assert( pData!=0 );
-  assert( pData+nData>pData );
-
-  /* Must lead with a varint(0) */
-  n = fts3GetVarint32(pData, &iDummy);
-  assert( iDummy==0 );
-  assert( n>0 );
-  assert( n0 );
-  assert( iDummy>0 );
-  assert( n+iDummy>0 );
-  assert( n+iDummy0 );
-  assert( iDummy>0 );
-  assert( n+iDummy>0 );
-  assert( n+iDummy<=nData );
-  ASSERT_VALID_DOCLIST(DL_DEFAULT, pData+n, iDummy, NULL);
-  pData += n+iDummy;
-  nData -= n+iDummy;
+/* Turn bulk memory into a hash table object by initializing the
+** fields of the Hash structure.
+**
+** "pNew" is a pointer to the hash table that is to be initialized.
+** keyClass is one of the constants 
+** FTS3_HASH_BINARY or FTS3_HASH_STRING.  The value of keyClass 
+** determines what kind of key the hash table will use.  "copyKey" is
+** true if the hash table should make its own private copy of keys and
+** false if it should just use the supplied pointer.
+*/
+SQLITE_PRIVATE void sqlite3Fts3HashInit(fts3Hash *pNew, int keyClass, int copyKey){
+  assert( pNew!=0 );
+  assert( keyClass>=FTS3_HASH_STRING && keyClass<=FTS3_HASH_BINARY );
+  pNew->keyClass = keyClass;
+  pNew->copyKey = copyKey;
+  pNew->first = 0;
+  pNew->count = 0;
+  pNew->htsize = 0;
+  pNew->ht = 0;
+}
 
-  /* Verify that trailing terms and doclists also are readable. */
-  while( nData!=0 ){
-    n = fts3GetVarint32(pData, &iDummy);
-    assert( n>0 );
-    assert( iDummy>=0 );
-    assert( n0 );
-    assert( iDummy>0 );
-    assert( n+iDummy>0 );
-    assert( n+iDummy0 );
-    assert( iDummy>0 );
-    assert( n+iDummy>0 );
-    assert( n+iDummy<=nData );
-    ASSERT_VALID_DOCLIST(DL_DEFAULT, pData+n, iDummy, NULL);
-    pData += n+iDummy;
-    nData -= n+iDummy;
+  assert( pH!=0 );
+  elem = pH->first;
+  pH->first = 0;
+  fts3HashFree(pH->ht);
+  pH->ht = 0;
+  pH->htsize = 0;
+  while( elem ){
+    fts3HashElem *next_elem = elem->next;
+    if( pH->copyKey && elem->pKey ){
+      fts3HashFree(elem->pKey);
+    }
+    fts3HashFree(elem);
+    elem = next_elem;
   }
+  pH->count = 0;
 }
-#define ASSERT_VALID_LEAF_NODE(p, n) leafNodeValidate(p, n)
-#else
-#define ASSERT_VALID_LEAF_NODE(p, n) assert( 1 )
-#endif
 
-/* Flush the current leaf node to %_segments, and adding the resulting
-** blockid and the starting term to the interior node which will
-** contain it.
+/*
+** Hash and comparison functions when the mode is FTS3_HASH_STRING
 */
-static int leafWriterInternalFlush(fulltext_vtab *v, LeafWriter *pWriter,
-                                   int iData, int nData){
-  sqlite_int64 iBlockid = 0;
-  const char *pStartingTerm;
-  int nStartingTerm, rc, n;
-
-  /* Must have the leading varint(0) flag, plus at least some
-  ** valid-looking data.
-  */
-  assert( nData>2 );
-  assert( iData>=0 );
-  assert( iData+nData<=pWriter->data.nData );
-  ASSERT_VALID_LEAF_NODE(pWriter->data.pData+iData, nData);
-
-  rc = block_insert(v, pWriter->data.pData+iData, nData, &iBlockid);
-  if( rc!=SQLITE_OK ) return rc;
-  assert( iBlockid!=0 );
+static int fts3StrHash(const void *pKey, int nKey){
+  const char *z = (const char *)pKey;
+  int h = 0;
+  if( nKey<=0 ) nKey = (int) strlen(z);
+  while( nKey > 0  ){
+    h = (h<<3) ^ h ^ *z++;
+    nKey--;
+  }
+  return h & 0x7fffffff;
+}
+static int fts3StrCompare(const void *pKey1, int n1, const void *pKey2, int n2){
+  if( n1!=n2 ) return 1;
+  return strncmp((const char*)pKey1,(const char*)pKey2,n1);
+}
 
-  /* Reconstruct the first term in the leaf for purposes of building
-  ** the interior node.
-  */
-  n = fts3GetVarint32(pWriter->data.pData+iData+1, &nStartingTerm);
-  pStartingTerm = pWriter->data.pData+iData+1+n;
-  assert( pWriter->data.nData>iData+1+n+nStartingTerm );
-  assert( pWriter->nTermDistinct>0 );
-  assert( pWriter->nTermDistinct<=nStartingTerm );
-  nStartingTerm = pWriter->nTermDistinct;
+/*
+** Hash and comparison functions when the mode is FTS3_HASH_BINARY
+*/
+static int fts3BinHash(const void *pKey, int nKey){
+  int h = 0;
+  const char *z = (const char *)pKey;
+  while( nKey-- > 0 ){
+    h = (h<<3) ^ h ^ *(z++);
+  }
+  return h & 0x7fffffff;
+}
+static int fts3BinCompare(const void *pKey1, int n1, const void *pKey2, int n2){
+  if( n1!=n2 ) return 1;
+  return memcmp(pKey1,pKey2,n1);
+}
 
-  if( pWriter->has_parent ){
-    interiorWriterAppend(&pWriter->parentWriter,
-                         pStartingTerm, nStartingTerm, iBlockid);
+/*
+** Return a pointer to the appropriate hash function given the key class.
+**
+** The C syntax in this function definition may be unfamilar to some 
+** programmers, so we provide the following additional explanation:
+**
+** The name of the function is "ftsHashFunction".  The function takes a
+** single parameter "keyClass".  The return value of ftsHashFunction()
+** is a pointer to another function.  Specifically, the return value
+** of ftsHashFunction() is a pointer to a function that takes two parameters
+** with types "const void*" and "int" and returns an "int".
+*/
+static int (*ftsHashFunction(int keyClass))(const void*,int){
+  if( keyClass==FTS3_HASH_STRING ){
+    return &fts3StrHash;
   }else{
-    interiorWriterInit(1, pStartingTerm, nStartingTerm, iBlockid,
-                       &pWriter->parentWriter);
-    pWriter->has_parent = 1;
+    assert( keyClass==FTS3_HASH_BINARY );
+    return &fts3BinHash;
   }
+}
 
-  /* Track the span of this segment's leaf nodes. */
-  if( pWriter->iEndBlockid==0 ){
-    pWriter->iEndBlockid = pWriter->iStartBlockid = iBlockid;
+/*
+** Return a pointer to the appropriate hash function given the key class.
+**
+** For help in interpreted the obscure C code in the function definition,
+** see the header comment on the previous function.
+*/
+static int (*ftsCompareFunction(int keyClass))(const void*,int,const void*,int){
+  if( keyClass==FTS3_HASH_STRING ){
+    return &fts3StrCompare;
   }else{
-    pWriter->iEndBlockid++;
-    assert( iBlockid==pWriter->iEndBlockid );
+    assert( keyClass==FTS3_HASH_BINARY );
+    return &fts3BinCompare;
   }
+}
 
-  return SQLITE_OK;
+/* Link an element into the hash table
+*/
+static void fts3HashInsertElement(
+  fts3Hash *pH,            /* The complete hash table */
+  struct _fts3ht *pEntry,  /* The entry into which pNew is inserted */
+  fts3HashElem *pNew       /* The element to be inserted */
+){
+  fts3HashElem *pHead;     /* First element already in pEntry */
+  pHead = pEntry->chain;
+  if( pHead ){
+    pNew->next = pHead;
+    pNew->prev = pHead->prev;
+    if( pHead->prev ){ pHead->prev->next = pNew; }
+    else             { pH->first = pNew; }
+    pHead->prev = pNew;
+  }else{
+    pNew->next = pH->first;
+    if( pH->first ){ pH->first->prev = pNew; }
+    pNew->prev = 0;
+    pH->first = pNew;
+  }
+  pEntry->count++;
+  pEntry->chain = pNew;
 }
-static int leafWriterFlush(fulltext_vtab *v, LeafWriter *pWriter){
-  int rc = leafWriterInternalFlush(v, pWriter, 0, pWriter->data.nData);
-  if( rc!=SQLITE_OK ) return rc;
 
-  /* Re-initialize the output buffer. */
-  dataBufferReset(&pWriter->data);
 
-  return SQLITE_OK;
+/* Resize the hash table so that it cantains "new_size" buckets.
+** "new_size" must be a power of 2.  The hash table might fail 
+** to resize if sqliteMalloc() fails.
+*/
+static void fts3Rehash(fts3Hash *pH, int new_size){
+  struct _fts3ht *new_ht;          /* The new hash table */
+  fts3HashElem *elem, *next_elem;  /* For looping over existing elements */
+  int (*xHash)(const void*,int);   /* The hash function */
+
+  assert( (new_size & (new_size-1))==0 );
+  new_ht = (struct _fts3ht *)fts3HashMalloc( new_size*sizeof(struct _fts3ht) );
+  if( new_ht==0 ) return;
+  fts3HashFree(pH->ht);
+  pH->ht = new_ht;
+  pH->htsize = new_size;
+  xHash = ftsHashFunction(pH->keyClass);
+  for(elem=pH->first, pH->first=0; elem; elem = next_elem){
+    int h = (*xHash)(elem->pKey, elem->nKey) & (new_size-1);
+    next_elem = elem->next;
+    fts3HashInsertElement(pH, &new_ht[h], elem);
+  }
 }
 
-/* Fetch the root info for the segment.  If the entire leaf fits
-** within ROOT_MAX, then it will be returned directly, otherwise it
-** will be flushed and the root info will be returned from the
-** interior node.  *piEndBlockid is set to the blockid of the last
-** interior or leaf node written to disk (0 if none are written at
-** all).
+/* This function (for internal use only) locates an element in an
+** hash table that matches the given key.  The hash for this key has
+** already been computed and is passed as the 4th parameter.
 */
-static int leafWriterRootInfo(fulltext_vtab *v, LeafWriter *pWriter,
-                              char **ppRootInfo, int *pnRootInfo,
-                              sqlite_int64 *piEndBlockid){
-  /* we can fit the segment entirely inline */
-  if( !pWriter->has_parent && pWriter->data.nDatadata.pData;
-    *pnRootInfo = pWriter->data.nData;
-    *piEndBlockid = 0;
-    return SQLITE_OK;
+static fts3HashElem *fts3FindElementByHash(
+  const fts3Hash *pH, /* The pH to be searched */
+  const void *pKey,   /* The key we are searching for */
+  int nKey,
+  int h               /* The hash for this key. */
+){
+  fts3HashElem *elem;            /* Used to loop thru the element list */
+  int count;                     /* Number of elements left to test */
+  int (*xCompare)(const void*,int,const void*,int);  /* comparison function */
+
+  if( pH->ht ){
+    struct _fts3ht *pEntry = &pH->ht[h];
+    elem = pEntry->chain;
+    count = pEntry->count;
+    xCompare = ftsCompareFunction(pH->keyClass);
+    while( count-- && elem ){
+      if( (*xCompare)(elem->pKey,elem->nKey,pKey,nKey)==0 ){ 
+        return elem;
+      }
+      elem = elem->next;
+    }
   }
+  return 0;
+}
 
-  /* Flush remaining leaf data. */
-  if( pWriter->data.nData>0 ){
-    int rc = leafWriterFlush(v, pWriter);
-    if( rc!=SQLITE_OK ) return rc;
+/* Remove a single entry from the hash table given a pointer to that
+** element and a hash on the element's key.
+*/
+static void fts3RemoveElementByHash(
+  fts3Hash *pH,         /* The pH containing "elem" */
+  fts3HashElem* elem,   /* The element to be removed from the pH */
+  int h                 /* Hash value for the element */
+){
+  struct _fts3ht *pEntry;
+  if( elem->prev ){
+    elem->prev->next = elem->next; 
+  }else{
+    pH->first = elem->next;
+  }
+  if( elem->next ){
+    elem->next->prev = elem->prev;
+  }
+  pEntry = &pH->ht[h];
+  if( pEntry->chain==elem ){
+    pEntry->chain = elem->next;
+  }
+  pEntry->count--;
+  if( pEntry->count<=0 ){
+    pEntry->chain = 0;
+  }
+  if( pH->copyKey && elem->pKey ){
+    fts3HashFree(elem->pKey);
+  }
+  fts3HashFree( elem );
+  pH->count--;
+  if( pH->count<=0 ){
+    assert( pH->first==0 );
+    assert( pH->count==0 );
+    fts3HashClear(pH);
   }
-
-  /* We must have flushed a leaf at some point. */
-  assert( pWriter->has_parent );
-
-  /* Tenatively set the end leaf blockid as the end blockid.  If the
-  ** interior node can be returned inline, this will be the final
-  ** blockid, otherwise it will be overwritten by
-  ** interiorWriterRootInfo().
-  */
-  *piEndBlockid = pWriter->iEndBlockid;
-
-  return interiorWriterRootInfo(v, &pWriter->parentWriter,
-                                ppRootInfo, pnRootInfo, piEndBlockid);
 }
 
-/* Collect the rootInfo data and store it into the segment directory.
-** This has the effect of flushing the segment's leaf data to
-** %_segments, and also flushing any interior nodes to %_segments.
+/* Attempt to locate an element of the hash table pH with a key
+** that matches pKey,nKey.  Return the data for this element if it is
+** found, or NULL if there is no match.
 */
-static int leafWriterFinalize(fulltext_vtab *v, LeafWriter *pWriter){
-  sqlite_int64 iEndBlockid;
-  char *pRootInfo;
-  int rc, nRootInfo;
-
-  rc = leafWriterRootInfo(v, pWriter, &pRootInfo, &nRootInfo, &iEndBlockid);
-  if( rc!=SQLITE_OK ) return rc;
-
-  /* Don't bother storing an entirely empty segment. */
-  if( iEndBlockid==0 && nRootInfo==0 ) return SQLITE_OK;
-
-  return segdir_set(v, pWriter->iLevel, pWriter->idx,
-                    pWriter->iStartBlockid, pWriter->iEndBlockid,
-                    iEndBlockid, pRootInfo, nRootInfo);
-}
+SQLITE_PRIVATE void *sqlite3Fts3HashFind(const fts3Hash *pH, const void *pKey, int nKey){
+  int h;                 /* A hash on key */
+  fts3HashElem *elem;    /* The element that matches key */
+  int (*xHash)(const void*,int);  /* The hash function */
 
-static void leafWriterDestroy(LeafWriter *pWriter){
-  if( pWriter->has_parent ) interiorWriterDestroy(&pWriter->parentWriter);
-  dataBufferDestroy(&pWriter->term);
-  dataBufferDestroy(&pWriter->data);
+  if( pH==0 || pH->ht==0 ) return 0;
+  xHash = ftsHashFunction(pH->keyClass);
+  assert( xHash!=0 );
+  h = (*xHash)(pKey,nKey);
+  assert( (pH->htsize & (pH->htsize-1))==0 );
+  elem = fts3FindElementByHash(pH,pKey,nKey, h & (pH->htsize-1));
+  return elem ? elem->data : 0;
 }
 
-/* Encode a term into the leafWriter, delta-encoding as appropriate.
-** Returns the length of the new term which distinguishes it from the
-** previous term, which can be used to set nTermDistinct when a node
-** boundary is crossed.
+/* Insert an element into the hash table pH.  The key is pKey,nKey
+** and the data is "data".
+**
+** If no element exists with a matching key, then a new
+** element is created.  A copy of the key is made if the copyKey
+** flag is set.  NULL is returned.
+**
+** If another element already exists with the same key, then the
+** new data replaces the old data and the old data is returned.
+** The key is not copied in this instance.  If a malloc fails, then
+** the new data is returned and the hash table is unchanged.
+**
+** If the "data" parameter to this function is NULL, then the
+** element corresponding to "key" is removed from the hash table.
 */
-static int leafWriterEncodeTerm(LeafWriter *pWriter,
-                                const char *pTerm, int nTerm){
-  char c[VARINT_MAX+VARINT_MAX];
-  int n, nPrefix = 0;
+SQLITE_PRIVATE void *sqlite3Fts3HashInsert(
+  fts3Hash *pH,        /* The hash table to insert into */
+  const void *pKey,    /* The key */
+  int nKey,            /* Number of bytes in the key */
+  void *data           /* The data */
+){
+  int hraw;                 /* Raw hash value of the key */
+  int h;                    /* the hash of the key modulo hash table size */
+  fts3HashElem *elem;       /* Used to loop thru the element list */
+  fts3HashElem *new_elem;   /* New element added to the pH */
+  int (*xHash)(const void*,int);  /* The hash function */
 
-  assert( nTerm>0 );
-  while( nPrefixterm.nData &&
-         pTerm[nPrefix]==pWriter->term.pData[nPrefix] ){
-    nPrefix++;
-    /* Failing this implies that the terms weren't in order. */
-    assert( nPrefixkeyClass);
+  assert( xHash!=0 );
+  hraw = (*xHash)(pKey, nKey);
+  assert( (pH->htsize & (pH->htsize-1))==0 );
+  h = hraw & (pH->htsize-1);
+  elem = fts3FindElementByHash(pH,pKey,nKey,h);
+  if( elem ){
+    void *old_data = elem->data;
+    if( data==0 ){
+      fts3RemoveElementByHash(pH,elem,h);
+    }else{
+      elem->data = data;
+    }
+    return old_data;
   }
-
-  if( pWriter->data.nData==0 ){
-    /* Encode the node header and leading term as:
-    **  varint(0)
-    **  varint(nTerm)
-    **  char pTerm[nTerm]
-    */
-    n = fts3PutVarint(c, '\0');
-    n += fts3PutVarint(c+n, nTerm);
-    dataBufferAppend2(&pWriter->data, c, n, pTerm, nTerm);
+  if( data==0 ) return 0;
+  new_elem = (fts3HashElem*)fts3HashMalloc( sizeof(fts3HashElem) );
+  if( new_elem==0 ) return data;
+  if( pH->copyKey && pKey!=0 ){
+    new_elem->pKey = fts3HashMalloc( nKey );
+    if( new_elem->pKey==0 ){
+      fts3HashFree(new_elem);
+      return data;
+    }
+    memcpy((void*)new_elem->pKey, pKey, nKey);
   }else{
-    /* Delta-encode the term as:
-    **  varint(nPrefix)
-    **  varint(nSuffix)
-    **  char pTermSuffix[nSuffix]
-    */
-    n = fts3PutVarint(c, nPrefix);
-    n += fts3PutVarint(c+n, nTerm-nPrefix);
-    dataBufferAppend2(&pWriter->data, c, n, pTerm+nPrefix, nTerm-nPrefix);
+    new_elem->pKey = (void*)pKey;
   }
-  dataBufferReplace(&pWriter->term, pTerm, nTerm);
-
-  return nPrefix+1;
+  new_elem->nKey = nKey;
+  pH->count++;
+  if( pH->htsize==0 ){
+    fts3Rehash(pH,8);
+    if( pH->htsize==0 ){
+      pH->count = 0;
+      fts3HashFree(new_elem);
+      return data;
+    }
+  }
+  if( pH->count > pH->htsize ){
+    fts3Rehash(pH,pH->htsize*2);
+  }
+  assert( pH->htsize>0 );
+  assert( (pH->htsize & (pH->htsize-1))==0 );
+  h = hraw & (pH->htsize-1);
+  fts3HashInsertElement(pH, &pH->ht[h], new_elem);
+  new_elem->data = data;
+  return 0;
 }
 
-/* Used to avoid a memmove when a large amount of doclist data is in
-** the buffer.  This constructs a node and term header before
-** iDoclistData and flushes the resulting complete node using
-** leafWriterInternalFlush().
-*/
-static int leafWriterInlineFlush(fulltext_vtab *v, LeafWriter *pWriter,
-                                 const char *pTerm, int nTerm,
-                                 int iDoclistData){
-  char c[VARINT_MAX+VARINT_MAX];
-  int iData, n = fts3PutVarint(c, 0);
-  n += fts3PutVarint(c+n, nTerm);
-
-  /* There should always be room for the header.  Even if pTerm shared
-  ** a substantial prefix with the previous term, the entire prefix
-  ** could be constructed from earlier data in the doclist, so there
-  ** should be room.
-  */
-  assert( iDoclistData>=n+nTerm );
-
-  iData = iDoclistData-(n+nTerm);
-  memcpy(pWriter->data.pData+iData, c, n);
-  memcpy(pWriter->data.pData+iData+n, pTerm, nTerm);
-
-  return leafWriterInternalFlush(v, pWriter, iData, pWriter->data.nData-iData);
-}
+#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
 
-/* Push pTerm[nTerm] along with the doclist data to the leaf layer of
-** %_segments.
+/************** End of fts3_hash.c *******************************************/
+/************** Begin file fts3_porter.c *************************************/
+/*
+** 2006 September 30
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** Implementation of the full-text-search tokenizer that implements
+** a Porter stemmer.
 */
-static int leafWriterStepMerge(fulltext_vtab *v, LeafWriter *pWriter,
-                               const char *pTerm, int nTerm,
-                               DLReader *pReaders, int nReaders){
-  char c[VARINT_MAX+VARINT_MAX];
-  int iTermData = pWriter->data.nData, iDoclistData;
-  int i, nData, n, nActualData, nActual, rc, nTermDistinct;
-
-  ASSERT_VALID_LEAF_NODE(pWriter->data.pData, pWriter->data.nData);
-  nTermDistinct = leafWriterEncodeTerm(pWriter, pTerm, nTerm);
-
-  /* Remember nTermDistinct if opening a new node. */
-  if( iTermData==0 ) pWriter->nTermDistinct = nTermDistinct;
-
-  iDoclistData = pWriter->data.nData;
-
-  /* Estimate the length of the merged doclist so we can leave space
-  ** to encode it.
-  */
-  for(i=0, nData=0; idata, c, n);
 
-  docListMerge(&pWriter->data, pReaders, nReaders);
-  ASSERT_VALID_DOCLIST(DL_DEFAULT,
-                       pWriter->data.pData+iDoclistData+n,
-                       pWriter->data.nData-iDoclistData-n, NULL);
+/*
+** The code in this file is only compiled if:
+**
+**     * The FTS3 module is being built as an extension
+**       (in which case SQLITE_CORE is not defined), or
+**
+**     * The FTS3 module is being built into the core of
+**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
+*/
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
 
-  /* The actual amount of doclist data at this point could be smaller
-  ** than the length we encoded.  Additionally, the space required to
-  ** encode this length could be smaller.  For small doclists, this is
-  ** not a big deal, we can just use memmove() to adjust things.
-  */
-  nActualData = pWriter->data.nData-(iDoclistData+n);
-  nActual = fts3PutVarint(c, nActualData);
-  assert( nActualData<=nData );
-  assert( nActual<=n );
 
-  /* If the new doclist is big enough for force a standalone leaf
-  ** node, we can immediately flush it inline without doing the
-  ** memmove().
-  */
-  /* TODO(shess) This test matches leafWriterStep(), which does this
-  ** test before it knows the cost to varint-encode the term and
-  ** doclist lengths.  At some point, change to
-  ** pWriter->data.nData-iTermData>STANDALONE_MIN.
-  */
-  if( nTerm+nActualData>STANDALONE_MIN ){
-    /* Push leaf node from before this term. */
-    if( iTermData>0 ){
-      rc = leafWriterInternalFlush(v, pWriter, 0, iTermData);
-      if( rc!=SQLITE_OK ) return rc;
 
-      pWriter->nTermDistinct = nTermDistinct;
-    }
 
-    /* Fix the encoded doclist length. */
-    iDoclistData += n - nActual;
-    memcpy(pWriter->data.pData+iDoclistData, c, nActual);
+/*
+** Class derived from sqlite3_tokenizer
+*/
+typedef struct porter_tokenizer {
+  sqlite3_tokenizer base;      /* Base class */
+} porter_tokenizer;
 
-    /* Push the standalone leaf node. */
-    rc = leafWriterInlineFlush(v, pWriter, pTerm, nTerm, iDoclistData);
-    if( rc!=SQLITE_OK ) return rc;
+/*
+** Class derived from sqlit3_tokenizer_cursor
+*/
+typedef struct porter_tokenizer_cursor {
+  sqlite3_tokenizer_cursor base;
+  const char *zInput;          /* input we are tokenizing */
+  int nInput;                  /* size of the input */
+  int iOffset;                 /* current position in zInput */
+  int iToken;                  /* index of next token to be returned */
+  char *zToken;                /* storage for current token */
+  int nAllocated;              /* space allocated to zToken buffer */
+} porter_tokenizer_cursor;
 
-    /* Leave the node empty. */
-    dataBufferReset(&pWriter->data);
 
-    return rc;
-  }
+/* Forward declaration */
+static const sqlite3_tokenizer_module porterTokenizerModule;
 
-  /* At this point, we know that the doclist was small, so do the
-  ** memmove if indicated.
-  */
-  if( nActualdata.pData+iDoclistData+nActual,
-            pWriter->data.pData+iDoclistData+n,
-            pWriter->data.nData-(iDoclistData+n));
-    pWriter->data.nData -= n-nActual;
-  }
 
-  /* Replace written length with actual length. */
-  memcpy(pWriter->data.pData+iDoclistData, c, nActual);
+/*
+** Create a new tokenizer instance.
+*/
+static int porterCreate(
+  int argc, const char * const *argv,
+  sqlite3_tokenizer **ppTokenizer
+){
+  porter_tokenizer *t;
+  t = (porter_tokenizer *) sqlite3_malloc(sizeof(*t));
+  if( t==NULL ) return SQLITE_NOMEM;
+  memset(t, 0, sizeof(*t));
+  *ppTokenizer = &t->base;
+  return SQLITE_OK;
+}
 
-  /* If the node is too large, break things up. */
-  /* TODO(shess) This test matches leafWriterStep(), which does this
-  ** test before it knows the cost to varint-encode the term and
-  ** doclist lengths.  At some point, change to
-  ** pWriter->data.nData>LEAF_MAX.
-  */
-  if( iTermData+nTerm+nActualData>LEAF_MAX ){
-    /* Flush out the leading data as a node */
-    rc = leafWriterInternalFlush(v, pWriter, 0, iTermData);
-    if( rc!=SQLITE_OK ) return rc;
+/*
+** Destroy a tokenizer
+*/
+static int porterDestroy(sqlite3_tokenizer *pTokenizer){
+  sqlite3_free(pTokenizer);
+  return SQLITE_OK;
+}
 
-    pWriter->nTermDistinct = nTermDistinct;
+/*
+** Prepare to begin tokenizing a particular string.  The input
+** string to be tokenized is zInput[0..nInput-1].  A cursor
+** used to incrementally tokenize this string is returned in 
+** *ppCursor.
+*/
+static int porterOpen(
+  sqlite3_tokenizer *pTokenizer,         /* The tokenizer */
+  const char *zInput, int nInput,        /* String to be tokenized */
+  sqlite3_tokenizer_cursor **ppCursor    /* OUT: Tokenization cursor */
+){
+  porter_tokenizer_cursor *c;
 
-    /* Rebuild header using the current term */
-    n = fts3PutVarint(pWriter->data.pData, 0);
-    n += fts3PutVarint(pWriter->data.pData+n, nTerm);
-    memcpy(pWriter->data.pData+n, pTerm, nTerm);
-    n += nTerm;
+  c = (porter_tokenizer_cursor *) sqlite3_malloc(sizeof(*c));
+  if( c==NULL ) return SQLITE_NOMEM;
 
-    /* There should always be room, because the previous encoding
-    ** included all data necessary to construct the term.
-    */
-    assert( ndata.nData-iDoclistDatadata.pData+n,
-           pWriter->data.pData+iDoclistData,
-           pWriter->data.nData-iDoclistData);
-    pWriter->data.nData -= iDoclistData-n;
+  c->zInput = zInput;
+  if( zInput==0 ){
+    c->nInput = 0;
+  }else if( nInput<0 ){
+    c->nInput = (int)strlen(zInput);
+  }else{
+    c->nInput = nInput;
   }
-  ASSERT_VALID_LEAF_NODE(pWriter->data.pData, pWriter->data.nData);
+  c->iOffset = 0;                 /* start tokenizing at the beginning */
+  c->iToken = 0;
+  c->zToken = NULL;               /* no space allocated, yet. */
+  c->nAllocated = 0;
 
+  *ppCursor = &c->base;
   return SQLITE_OK;
 }
 
-/* Push pTerm[nTerm] along with the doclist data to the leaf layer of
-** %_segments.
+/*
+** Close a tokenization cursor previously opened by a call to
+** porterOpen() above.
 */
-/* TODO(shess) Revise writeZeroSegment() so that doclists are
-** constructed directly in pWriter->data.
+static int porterClose(sqlite3_tokenizer_cursor *pCursor){
+  porter_tokenizer_cursor *c = (porter_tokenizer_cursor *) pCursor;
+  sqlite3_free(c->zToken);
+  sqlite3_free(c);
+  return SQLITE_OK;
+}
+/*
+** Vowel or consonant
 */
-static int leafWriterStep(fulltext_vtab *v, LeafWriter *pWriter,
-                          const char *pTerm, int nTerm,
-                          const char *pData, int nData){
-  int rc;
-  DLReader reader;
+static const char cType[] = {
+   0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0,
+   1, 1, 1, 2, 1
+};
 
-  dlrInit(&reader, DL_DEFAULT, pData, nData);
-  rc = leafWriterStepMerge(v, pWriter, pTerm, nTerm, &reader, 1);
-  dlrDestroy(&reader);
+/*
+** isConsonant() and isVowel() determine if their first character in
+** the string they point to is a consonant or a vowel, according
+** to Porter ruls.  
+**
+** A consonate is any letter other than 'a', 'e', 'i', 'o', or 'u'.
+** 'Y' is a consonant unless it follows another consonant,
+** in which case it is a vowel.
+**
+** In these routine, the letters are in reverse order.  So the 'y' rule
+** is that 'y' is a consonant unless it is followed by another
+** consonent.
+*/
+static int isVowel(const char*);
+static int isConsonant(const char *z){
+  int j;
+  char x = *z;
+  if( x==0 ) return 0;
+  assert( x>='a' && x<='z' );
+  j = cType[x-'a'];
+  if( j<2 ) return j;
+  return z[1]==0 || isVowel(z + 1);
+}
+static int isVowel(const char *z){
+  int j;
+  char x = *z;
+  if( x==0 ) return 0;
+  assert( x>='a' && x<='z' );
+  j = cType[x-'a'];
+  if( j<2 ) return 1-j;
+  return isConsonant(z + 1);
+}
 
-  return rc;
+/*
+** Let any sequence of one or more vowels be represented by V and let
+** C be sequence of one or more consonants.  Then every word can be
+** represented as:
+**
+**           [C] (VC){m} [V]
+**
+** In prose:  A word is an optional consonant followed by zero or
+** vowel-consonant pairs followed by an optional vowel.  "m" is the
+** number of vowel consonant pairs.  This routine computes the value
+** of m for the first i bytes of a word.
+**
+** Return true if the m-value for z is 1 or more.  In other words,
+** return true if z contains at least one vowel that is followed
+** by a consonant.
+**
+** In this routine z[] is in reverse order.  So we are really looking
+** for an instance of of a consonant followed by a vowel.
+*/
+static int m_gt_0(const char *z){
+  while( isVowel(z) ){ z++; }
+  if( *z==0 ) return 0;
+  while( isConsonant(z) ){ z++; }
+  return *z!=0;
 }
 
+/* Like mgt0 above except we are looking for a value of m which is
+** exactly 1
+*/
+static int m_eq_1(const char *z){
+  while( isVowel(z) ){ z++; }
+  if( *z==0 ) return 0;
+  while( isConsonant(z) ){ z++; }
+  if( *z==0 ) return 0;
+  while( isVowel(z) ){ z++; }
+  if( *z==0 ) return 1;
+  while( isConsonant(z) ){ z++; }
+  return *z==0;
+}
 
-/****************************************************************/
-/* LeafReader is used to iterate over an individual leaf node. */
-typedef struct LeafReader {
-  DataBuffer term;          /* copy of current term. */
+/* Like mgt0 above except we are looking for a value of m>1 instead
+** or m>0
+*/
+static int m_gt_1(const char *z){
+  while( isVowel(z) ){ z++; }
+  if( *z==0 ) return 0;
+  while( isConsonant(z) ){ z++; }
+  if( *z==0 ) return 0;
+  while( isVowel(z) ){ z++; }
+  if( *z==0 ) return 0;
+  while( isConsonant(z) ){ z++; }
+  return *z!=0;
+}
 
-  const char *pData;        /* data for current term. */
-  int nData;
-} LeafReader;
+/*
+** Return TRUE if there is a vowel anywhere within z[0..n-1]
+*/
+static int hasVowel(const char *z){
+  while( isConsonant(z) ){ z++; }
+  return *z!=0;
+}
 
-static void leafReaderDestroy(LeafReader *pReader){
-  dataBufferDestroy(&pReader->term);
-  SCRAMBLE(pReader);
+/*
+** Return TRUE if the word ends in a double consonant.
+**
+** The text is reversed here. So we are really looking at
+** the first two characters of z[].
+*/
+static int doubleConsonant(const char *z){
+  return isConsonant(z) && z[0]==z[1] && isConsonant(z+1);
 }
 
-static int leafReaderAtEnd(LeafReader *pReader){
-  return pReader->nData<=0;
+/*
+** Return TRUE if the word ends with three letters which
+** are consonant-vowel-consonent and where the final consonant
+** is not 'w', 'x', or 'y'.
+**
+** The word is reversed here.  So we are really checking the
+** first three letters and the first one cannot be in [wxy].
+*/
+static int star_oh(const char *z){
+  return
+    z[0]!=0 && isConsonant(z) &&
+    z[0]!='w' && z[0]!='x' && z[0]!='y' &&
+    z[1]!=0 && isVowel(z+1) &&
+    z[2]!=0 && isConsonant(z+2);
 }
 
-/* Access the current term. */
-static int leafReaderTermBytes(LeafReader *pReader){
-  return pReader->term.nData;
-}
-static const char *leafReaderTerm(LeafReader *pReader){
-  assert( pReader->term.nData>0 );
-  return pReader->term.pData;
+/*
+** If the word ends with zFrom and xCond() is true for the stem
+** of the word that preceeds the zFrom ending, then change the 
+** ending to zTo.
+**
+** The input word *pz and zFrom are both in reverse order.  zTo
+** is in normal order. 
+**
+** Return TRUE if zFrom matches.  Return FALSE if zFrom does not
+** match.  Not that TRUE is returned even if xCond() fails and
+** no substitution occurs.
+*/
+static int stem(
+  char **pz,             /* The word being stemmed (Reversed) */
+  const char *zFrom,     /* If the ending matches this... (Reversed) */
+  const char *zTo,       /* ... change the ending to this (not reversed) */
+  int (*xCond)(const char*)   /* Condition that must be true */
+){
+  char *z = *pz;
+  while( *zFrom && *zFrom==*z ){ z++; zFrom++; }
+  if( *zFrom!=0 ) return 0;
+  if( xCond && !xCond(z) ) return 1;
+  while( *zTo ){
+    *(--z) = *(zTo++);
+  }
+  *pz = z;
+  return 1;
 }
 
-/* Access the doclist data for the current term. */
-static int leafReaderDataBytes(LeafReader *pReader){
-  int nData;
-  assert( pReader->term.nData>0 );
-  fts3GetVarint32(pReader->pData, &nData);
-  return nData;
-}
-static const char *leafReaderData(LeafReader *pReader){
-  int n, nData;
-  assert( pReader->term.nData>0 );
-  n = fts3GetVarint32(pReader->pData, &nData);
-  return pReader->pData+n;
+/*
+** This is the fallback stemmer used when the porter stemmer is
+** inappropriate.  The input word is copied into the output with
+** US-ASCII case folding.  If the input word is too long (more
+** than 20 bytes if it contains no digits or more than 6 bytes if
+** it contains digits) then word is truncated to 20 or 6 bytes
+** by taking 10 or 3 bytes from the beginning and end.
+*/
+static void copy_stemmer(const char *zIn, int nIn, char *zOut, int *pnOut){
+  int i, mx, j;
+  int hasDigit = 0;
+  for(i=0; i='A' && c<='Z' ){
+      zOut[i] = c - 'A' + 'a';
+    }else{
+      if( c>='0' && c<='9' ) hasDigit = 1;
+      zOut[i] = c;
+    }
+  }
+  mx = hasDigit ? 3 : 10;
+  if( nIn>mx*2 ){
+    for(j=mx, i=nIn-mx; i0 );
-  assert( pData[0]=='\0' );
+/*
+** Stem the input word zIn[0..nIn-1].  Store the output in zOut.
+** zOut is at least big enough to hold nIn bytes.  Write the actual
+** size of the output word (exclusive of the '\0' terminator) into *pnOut.
+**
+** Any upper-case characters in the US-ASCII character set ([A-Z])
+** are converted to lower case.  Upper-case UTF characters are
+** unchanged.
+**
+** Words that are longer than about 20 bytes are stemmed by retaining
+** a few bytes from the beginning and the end of the word.  If the
+** word contains digits, 3 bytes are taken from the beginning and
+** 3 bytes from the end.  For long words without digits, 10 bytes
+** are taken from each end.  US-ASCII case folding still applies.
+** 
+** If the input word contains not digits but does characters not 
+** in [a-zA-Z] then no stemming is attempted and this routine just 
+** copies the input into the input into the output with US-ASCII
+** case folding.
+**
+** Stemming never increases the length of the word.  So there is
+** no chance of overflowing the zOut buffer.
+*/
+static void porter_stemmer(const char *zIn, int nIn, char *zOut, int *pnOut){
+  int i, j, c;
+  char zReverse[28];
+  char *z, *z2;
+  if( nIn<3 || nIn>=sizeof(zReverse)-7 ){
+    /* The word is too big or too small for the porter stemmer.
+    ** Fallback to the copy stemmer */
+    copy_stemmer(zIn, nIn, zOut, pnOut);
+    return;
+  }
+  for(i=0, j=sizeof(zReverse)-6; i='A' && c<='Z' ){
+      zReverse[j] = c + 'a' - 'A';
+    }else if( c>='a' && c<='z' ){
+      zReverse[j] = c;
+    }else{
+      /* The use of a character not in [a-zA-Z] means that we fallback
+      ** to the copy stemmer */
+      copy_stemmer(zIn, nIn, zOut, pnOut);
+      return;
+    }
+  }
+  memset(&zReverse[sizeof(zReverse)-5], 0, 5);
+  z = &zReverse[j+1];
 
-  CLEAR(pReader);
 
-  /* Read the first term, skipping the header byte. */
-  n = fts3GetVarint32(pData+1, &nTerm);
-  dataBufferInit(&pReader->term, nTerm);
-  dataBufferReplace(&pReader->term, pData+1+n, nTerm);
+  /* Step 1a */
+  if( z[0]=='s' ){
+    if(
+     !stem(&z, "sess", "ss", 0) &&
+     !stem(&z, "sei", "i", 0)  &&
+     !stem(&z, "ss", "ss", 0)
+    ){
+      z++;
+    }
+  }
 
-  /* Position after the first term. */
-  assert( 1+n+nTermpData = pData+1+n+nTerm;
-  pReader->nData = nData-1-n-nTerm;
-}
+  /* Step 1b */  
+  z2 = z;
+  if( stem(&z, "dee", "ee", m_gt_0) ){
+    /* Do nothing.  The work was all in the test */
+  }else if( 
+     (stem(&z, "gni", "", hasVowel) || stem(&z, "de", "", hasVowel))
+      && z!=z2
+  ){
+     if( stem(&z, "ta", "ate", 0) ||
+         stem(&z, "lb", "ble", 0) ||
+         stem(&z, "zi", "ize", 0) ){
+       /* Do nothing.  The work was all in the test */
+     }else if( doubleConsonant(z) && (*z!='l' && *z!='s' && *z!='z') ){
+       z++;
+     }else if( m_eq_1(z) && star_oh(z) ){
+       *(--z) = 'e';
+     }
+  }
 
-/* Step the reader forward to the next term. */
-static void leafReaderStep(LeafReader *pReader){
-  int n, nData, nPrefix, nSuffix;
-  assert( !leafReaderAtEnd(pReader) );
+  /* Step 1c */
+  if( z[0]=='y' && hasVowel(z+1) ){
+    z[0] = 'i';
+  }
 
-  /* Skip previous entry's data block. */
-  n = fts3GetVarint32(pReader->pData, &nData);
-  assert( n+nData<=pReader->nData );
-  pReader->pData += n+nData;
-  pReader->nData -= n+nData;
+  /* Step 2 */
+  switch( z[1] ){
+   case 'a':
+     stem(&z, "lanoita", "ate", m_gt_0) ||
+     stem(&z, "lanoit", "tion", m_gt_0);
+     break;
+   case 'c':
+     stem(&z, "icne", "ence", m_gt_0) ||
+     stem(&z, "icna", "ance", m_gt_0);
+     break;
+   case 'e':
+     stem(&z, "rezi", "ize", m_gt_0);
+     break;
+   case 'g':
+     stem(&z, "igol", "log", m_gt_0);
+     break;
+   case 'l':
+     stem(&z, "ilb", "ble", m_gt_0) ||
+     stem(&z, "illa", "al", m_gt_0) ||
+     stem(&z, "iltne", "ent", m_gt_0) ||
+     stem(&z, "ile", "e", m_gt_0) ||
+     stem(&z, "ilsuo", "ous", m_gt_0);
+     break;
+   case 'o':
+     stem(&z, "noitazi", "ize", m_gt_0) ||
+     stem(&z, "noita", "ate", m_gt_0) ||
+     stem(&z, "rota", "ate", m_gt_0);
+     break;
+   case 's':
+     stem(&z, "msila", "al", m_gt_0) ||
+     stem(&z, "ssenevi", "ive", m_gt_0) ||
+     stem(&z, "ssenluf", "ful", m_gt_0) ||
+     stem(&z, "ssensuo", "ous", m_gt_0);
+     break;
+   case 't':
+     stem(&z, "itila", "al", m_gt_0) ||
+     stem(&z, "itivi", "ive", m_gt_0) ||
+     stem(&z, "itilib", "ble", m_gt_0);
+     break;
+  }
 
-  if( !leafReaderAtEnd(pReader) ){
-    /* Construct the new term using a prefix from the old term plus a
-    ** suffix from the leaf data.
-    */
-    n = fts3GetVarint32(pReader->pData, &nPrefix);
-    n += fts3GetVarint32(pReader->pData+n, &nSuffix);
-    assert( n+nSuffixnData );
-    pReader->term.nData = nPrefix;
-    dataBufferAppend(&pReader->term, pReader->pData+n, nSuffix);
+  /* Step 3 */
+  switch( z[0] ){
+   case 'e':
+     stem(&z, "etaci", "ic", m_gt_0) ||
+     stem(&z, "evita", "", m_gt_0)   ||
+     stem(&z, "ezila", "al", m_gt_0);
+     break;
+   case 'i':
+     stem(&z, "itici", "ic", m_gt_0);
+     break;
+   case 'l':
+     stem(&z, "laci", "ic", m_gt_0) ||
+     stem(&z, "luf", "", m_gt_0);
+     break;
+   case 's':
+     stem(&z, "ssen", "", m_gt_0);
+     break;
+  }
 
-    pReader->pData += n+nSuffix;
-    pReader->nData -= n+nSuffix;
+  /* Step 4 */
+  switch( z[1] ){
+   case 'a':
+     if( z[0]=='l' && m_gt_1(z+2) ){
+       z += 2;
+     }
+     break;
+   case 'c':
+     if( z[0]=='e' && z[2]=='n' && (z[3]=='a' || z[3]=='e')  && m_gt_1(z+4)  ){
+       z += 4;
+     }
+     break;
+   case 'e':
+     if( z[0]=='r' && m_gt_1(z+2) ){
+       z += 2;
+     }
+     break;
+   case 'i':
+     if( z[0]=='c' && m_gt_1(z+2) ){
+       z += 2;
+     }
+     break;
+   case 'l':
+     if( z[0]=='e' && z[2]=='b' && (z[3]=='a' || z[3]=='i') && m_gt_1(z+4) ){
+       z += 4;
+     }
+     break;
+   case 'n':
+     if( z[0]=='t' ){
+       if( z[2]=='a' ){
+         if( m_gt_1(z+3) ){
+           z += 3;
+         }
+       }else if( z[2]=='e' ){
+         stem(&z, "tneme", "", m_gt_1) ||
+         stem(&z, "tnem", "", m_gt_1) ||
+         stem(&z, "tne", "", m_gt_1);
+       }
+     }
+     break;
+   case 'o':
+     if( z[0]=='u' ){
+       if( m_gt_1(z+2) ){
+         z += 2;
+       }
+     }else if( z[3]=='s' || z[3]=='t' ){
+       stem(&z, "noi", "", m_gt_1);
+     }
+     break;
+   case 's':
+     if( z[0]=='m' && z[2]=='i' && m_gt_1(z+3) ){
+       z += 3;
+     }
+     break;
+   case 't':
+     stem(&z, "eta", "", m_gt_1) ||
+     stem(&z, "iti", "", m_gt_1);
+     break;
+   case 'u':
+     if( z[0]=='s' && z[2]=='o' && m_gt_1(z+3) ){
+       z += 3;
+     }
+     break;
+   case 'v':
+   case 'z':
+     if( z[0]=='e' && z[2]=='i' && m_gt_1(z+3) ){
+       z += 3;
+     }
+     break;
   }
-}
 
-/* strcmp-style comparison of pReader's current term against pTerm.
-** If isPrefix, equality means equal through nTerm bytes.
-*/
-static int leafReaderTermCmp(LeafReader *pReader,
-                             const char *pTerm, int nTerm, int isPrefix){
-  int c, n = pReader->term.nDataterm.nData : nTerm;
-  if( n==0 ){
-    if( pReader->term.nData>0 ) return -1;
-    if(nTerm>0 ) return 1;
-    return 0;
+  /* Step 5a */
+  if( z[0]=='e' ){
+    if( m_gt_1(z+1) ){
+      z++;
+    }else if( m_eq_1(z+1) && !star_oh(z+1) ){
+      z++;
+    }
   }
 
-  c = memcmp(pReader->term.pData, pTerm, n);
-  if( c!=0 ) return c;
-  if( isPrefix && n==nTerm ) return 0;
-  return pReader->term.nData - nTerm;
-}
+  /* Step 5b */
+  if( m_gt_1(z) && z[0]=='l' && z[1]=='l' ){
+    z++;
+  }
 
+  /* z[] is now the stemmed word in reverse order.  Flip it back
+  ** around into forward order and return.
+  */
+  *pnOut = i = strlen(z);
+  zOut[i] = 0;
+  while( *z ){
+    zOut[--i] = *(z++);
+  }
+}
 
-/****************************************************************/
-/* LeavesReader wraps LeafReader to allow iterating over the entire
-** leaf layer of the tree.
+/*
+** Characters that can be part of a token.  We assume any character
+** whose value is greater than 0x80 (any UTF character) can be
+** part of a token.  In other words, delimiters all must have
+** values of 0x7f or lower.
 */
-typedef struct LeavesReader {
-  int idx;                  /* Index within the segment. */
+static const char porterIdChar[] = {
+/* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,  /* 3x */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 4x */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1,  /* 5x */
+    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* 6x */
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,  /* 7x */
+};
+#define isDelim(C) (((ch=C)&0x80)==0 && (ch<0x30 || !porterIdChar[ch-0x30]))
 
-  sqlite3_stmt *pStmt;      /* Statement we're streaming leaves from. */
-  int eof;                  /* we've seen SQLITE_DONE from pStmt. */
+/*
+** Extract the next token from a tokenization cursor.  The cursor must
+** have been opened by a prior call to porterOpen().
+*/
+static int porterNext(
+  sqlite3_tokenizer_cursor *pCursor,  /* Cursor returned by porterOpen */
+  const char **pzToken,               /* OUT: *pzToken is the token text */
+  int *pnBytes,                       /* OUT: Number of bytes in token */
+  int *piStartOffset,                 /* OUT: Starting offset of token */
+  int *piEndOffset,                   /* OUT: Ending offset of token */
+  int *piPosition                     /* OUT: Position integer of token */
+){
+  porter_tokenizer_cursor *c = (porter_tokenizer_cursor *) pCursor;
+  const char *z = c->zInput;
 
-  LeafReader leafReader;    /* reader for the current leaf. */
-  DataBuffer rootData;      /* root data for inline. */
-} LeavesReader;
+  while( c->iOffsetnInput ){
+    int iStartOffset, ch;
 
-/* Access the current term. */
-static int leavesReaderTermBytes(LeavesReader *pReader){
-  assert( !pReader->eof );
-  return leafReaderTermBytes(&pReader->leafReader);
-}
-static const char *leavesReaderTerm(LeavesReader *pReader){
-  assert( !pReader->eof );
-  return leafReaderTerm(&pReader->leafReader);
-}
+    /* Scan past delimiter characters */
+    while( c->iOffsetnInput && isDelim(z[c->iOffset]) ){
+      c->iOffset++;
+    }
 
-/* Access the doclist data for the current term. */
-static int leavesReaderDataBytes(LeavesReader *pReader){
-  assert( !pReader->eof );
-  return leafReaderDataBytes(&pReader->leafReader);
-}
-static const char *leavesReaderData(LeavesReader *pReader){
-  assert( !pReader->eof );
-  return leafReaderData(&pReader->leafReader);
-}
+    /* Count non-delimiter characters. */
+    iStartOffset = c->iOffset;
+    while( c->iOffsetnInput && !isDelim(z[c->iOffset]) ){
+      c->iOffset++;
+    }
 
-static int leavesReaderAtEnd(LeavesReader *pReader){
-  return pReader->eof;
+    if( c->iOffset>iStartOffset ){
+      int n = c->iOffset-iStartOffset;
+      if( n>c->nAllocated ){
+        c->nAllocated = n+20;
+        c->zToken = sqlite3_realloc(c->zToken, c->nAllocated);
+        if( c->zToken==NULL ) return SQLITE_NOMEM;
+      }
+      porter_stemmer(&z[iStartOffset], n, c->zToken, pnBytes);
+      *pzToken = c->zToken;
+      *piStartOffset = iStartOffset;
+      *piEndOffset = c->iOffset;
+      *piPosition = c->iToken++;
+      return SQLITE_OK;
+    }
+  }
+  return SQLITE_DONE;
 }
 
-/* loadSegmentLeaves() may not read all the way to SQLITE_DONE, thus
-** leaving the statement handle open, which locks the table.
+/*
+** The set of routines that implement the porter-stemmer tokenizer
 */
-/* TODO(shess) This "solution" is not satisfactory.  Really, there
-** should be check-in function for all statement handles which
-** arranges to call sqlite3_reset().  This most likely will require
-** modification to control flow all over the place, though, so for now
-** just punt.
-**
-** Note the the current system assumes that segment merges will run to
-** completion, which is why this particular probably hasn't arisen in
-** this case.  Probably a brittle assumption.
+static const sqlite3_tokenizer_module porterTokenizerModule = {
+  0,
+  porterCreate,
+  porterDestroy,
+  porterOpen,
+  porterClose,
+  porterNext,
+};
+
+/*
+** Allocate a new porter tokenizer.  Return a pointer to the new
+** tokenizer in *ppModule
 */
-static int leavesReaderReset(LeavesReader *pReader){
-  return sqlite3_reset(pReader->pStmt);
+SQLITE_PRIVATE void sqlite3Fts3PorterTokenizerModule(
+  sqlite3_tokenizer_module const**ppModule
+){
+  *ppModule = &porterTokenizerModule;
 }
 
-static void leavesReaderDestroy(LeavesReader *pReader){
-  leafReaderDestroy(&pReader->leafReader);
-  dataBufferDestroy(&pReader->rootData);
-  SCRAMBLE(pReader);
-}
+#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
+
+/************** End of fts3_porter.c *****************************************/
+/************** Begin file fts3_tokenizer.c **********************************/
+/*
+** 2007 June 22
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This is part of an SQLite module implementing full-text search.
+** This particular file implements the generic tokenizer interface.
+*/
 
-/* Initialize pReader with the given root data (if iStartBlockid==0
-** the leaf data was entirely contained in the root), or from the
-** stream of blocks between iStartBlockid and iEndBlockid, inclusive.
+/*
+** The code in this file is only compiled if:
+**
+**     * The FTS3 module is being built as an extension
+**       (in which case SQLITE_CORE is not defined), or
+**
+**     * The FTS3 module is being built into the core of
+**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
 */
-static int leavesReaderInit(fulltext_vtab *v,
-                            int idx,
-                            sqlite_int64 iStartBlockid,
-                            sqlite_int64 iEndBlockid,
-                            const char *pRootData, int nRootData,
-                            LeavesReader *pReader){
-  CLEAR(pReader);
-  pReader->idx = idx;
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
 
-  dataBufferInit(&pReader->rootData, 0);
-  if( iStartBlockid==0 ){
-    /* Entire leaf level fit in root data. */
-    dataBufferReplace(&pReader->rootData, pRootData, nRootData);
-    leafReaderInit(pReader->rootData.pData, pReader->rootData.nData,
-                   &pReader->leafReader);
-  }else{
-    sqlite3_stmt *s;
-    int rc = sql_get_leaf_statement(v, idx, &s);
-    if( rc!=SQLITE_OK ) return rc;
+#ifndef SQLITE_CORE
+  SQLITE_EXTENSION_INIT1
+#endif
 
-    rc = sqlite3_bind_int64(s, 1, iStartBlockid);
-    if( rc!=SQLITE_OK ) return rc;
 
-    rc = sqlite3_bind_int64(s, 2, iEndBlockid);
-    if( rc!=SQLITE_OK ) return rc;
+/*
+** Implementation of the SQL scalar function for accessing the underlying 
+** hash table. This function may be called as follows:
+**
+**   SELECT ();
+**   SELECT (, );
+**
+** where  is the name passed as the second argument
+** to the sqlite3Fts3InitHashTable() function (e.g. 'fts3_tokenizer').
+**
+** If the  argument is specified, it must be a blob value
+** containing a pointer to be stored as the hash data corresponding
+** to the string . If  is not specified, then
+** the string  must already exist in the has table. Otherwise,
+** an error is returned.
+**
+** Whether or not the  argument is specified, the value returned
+** is a blob containing the pointer stored as the hash data corresponding
+** to string  (after the hash-table is updated, if applicable).
+*/
+static void scalarFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  fts3Hash *pHash;
+  void *pPtr = 0;
+  const unsigned char *zName;
+  int nName;
 
-    rc = sqlite3_step(s);
-    if( rc==SQLITE_DONE ){
-      pReader->eof = 1;
-      return SQLITE_OK;
-    }
-    if( rc!=SQLITE_ROW ) return rc;
+  assert( argc==1 || argc==2 );
 
-    pReader->pStmt = s;
-    leafReaderInit(sqlite3_column_blob(pReader->pStmt, 0),
-                   sqlite3_column_bytes(pReader->pStmt, 0),
-                   &pReader->leafReader);
-  }
-  return SQLITE_OK;
-}
+  pHash = (fts3Hash *)sqlite3_user_data(context);
 
-/* Step the current leaf forward to the next term.  If we reach the
-** end of the current leaf, step forward to the next leaf block.
-*/
-static int leavesReaderStep(fulltext_vtab *v, LeavesReader *pReader){
-  assert( !leavesReaderAtEnd(pReader) );
-  leafReaderStep(&pReader->leafReader);
+  zName = sqlite3_value_text(argv[0]);
+  nName = sqlite3_value_bytes(argv[0])+1;
 
-  if( leafReaderAtEnd(&pReader->leafReader) ){
-    int rc;
-    if( pReader->rootData.pData ){
-      pReader->eof = 1;
-      return SQLITE_OK;
+  if( argc==2 ){
+    void *pOld;
+    int n = sqlite3_value_bytes(argv[1]);
+    if( n!=sizeof(pPtr) ){
+      sqlite3_result_error(context, "argument type mismatch", -1);
+      return;
     }
-    rc = sqlite3_step(pReader->pStmt);
-    if( rc!=SQLITE_ROW ){
-      pReader->eof = 1;
-      return rc==SQLITE_DONE ? SQLITE_OK : rc;
+    pPtr = *(void **)sqlite3_value_blob(argv[1]);
+    pOld = sqlite3Fts3HashInsert(pHash, (void *)zName, nName, pPtr);
+    if( pOld==pPtr ){
+      sqlite3_result_error(context, "out of memory", -1);
+      return;
+    }
+  }else{
+    pPtr = sqlite3Fts3HashFind(pHash, zName, nName);
+    if( !pPtr ){
+      char *zErr = sqlite3_mprintf("unknown tokenizer: %s", zName);
+      sqlite3_result_error(context, zErr, -1);
+      sqlite3_free(zErr);
+      return;
     }
-    leafReaderDestroy(&pReader->leafReader);
-    leafReaderInit(sqlite3_column_blob(pReader->pStmt, 0),
-                   sqlite3_column_bytes(pReader->pStmt, 0),
-                   &pReader->leafReader);
   }
-  return SQLITE_OK;
+
+  sqlite3_result_blob(context, (void *)&pPtr, sizeof(pPtr), SQLITE_TRANSIENT);
 }
 
-/* Order LeavesReaders by their term, ignoring idx.  Readers at eof
-** always sort to the end.
-*/
-static int leavesReaderTermCmp(LeavesReader *lr1, LeavesReader *lr2){
-  if( leavesReaderAtEnd(lr1) ){
-    if( leavesReaderAtEnd(lr2) ) return 0;
-    return 1;
-  }
-  if( leavesReaderAtEnd(lr2) ) return -1;
+#ifdef SQLITE_TEST
 
-  return leafReaderTermCmp(&lr1->leafReader,
-                           leavesReaderTerm(lr2), leavesReaderTermBytes(lr2),
-                           0);
-}
 
-/* Similar to leavesReaderTermCmp(), with additional ordering by idx
-** so that older segments sort before newer segments.
+/*
+** Implementation of a special SQL scalar function for testing tokenizers 
+** designed to be used in concert with the Tcl testing framework. This
+** function must be called with two arguments:
+**
+**   SELECT (, );
+**   SELECT (, );
+**
+** where  is the name passed as the second argument
+** to the sqlite3Fts3InitHashTable() function (e.g. 'fts3_tokenizer')
+** concatenated with the string '_test' (e.g. 'fts3_tokenizer_test').
+**
+** The return value is a string that may be interpreted as a Tcl
+** list. For each token in the , three elements are
+** added to the returned list. The first is the token position, the 
+** second is the token text (folded, stemmed, etc.) and the third is the
+** substring of  associated with the token. For example, 
+** using the built-in "simple" tokenizer:
+**
+**   SELECT fts_tokenizer_test('simple', 'I don't see how');
+**
+** will return the string:
+**
+**   "{0 i I 1 dont don't 2 see see 3 how how}"
+**   
 */
-static int leavesReaderCmp(LeavesReader *lr1, LeavesReader *lr2){
-  int c = leavesReaderTermCmp(lr1, lr2);
-  if( c!=0 ) return c;
-  return lr1->idx-lr2->idx;
-}
+static void testFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  fts3Hash *pHash;
+  sqlite3_tokenizer_module *p;
+  sqlite3_tokenizer *pTokenizer = 0;
+  sqlite3_tokenizer_cursor *pCsr = 0;
 
-/* Assume that pLr[1]..pLr[nLr] are sorted.  Bubble pLr[0] into its
-** sorted position.
-*/
-static void leavesReaderReorder(LeavesReader *pLr, int nLr){
-  while( nLr>1 && leavesReaderCmp(pLr, pLr+1)>0 ){
-    LeavesReader tmp = pLr[0];
-    pLr[0] = pLr[1];
-    pLr[1] = tmp;
-    nLr--;
-    pLr++;
-  }
-}
+  const char *zErr = 0;
 
-/* Initializes pReaders with the segments from level iLevel, returning
-** the number of segments in *piReaders.  Leaves pReaders in sorted
-** order.
-*/
-static int leavesReadersInit(fulltext_vtab *v, int iLevel,
-                             LeavesReader *pReaders, int *piReaders){
-  sqlite3_stmt *s;
-  int i, rc = sql_get_statement(v, SEGDIR_SELECT_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+  const char *zName;
+  int nName;
+  const char *zInput;
+  int nInput;
 
-  rc = sqlite3_bind_int(s, 1, iLevel);
-  if( rc!=SQLITE_OK ) return rc;
+  const char *zArg = 0;
 
-  i = 0;
-  while( (rc = sqlite3_step(s))==SQLITE_ROW ){
-    sqlite_int64 iStart = sqlite3_column_int64(s, 0);
-    sqlite_int64 iEnd = sqlite3_column_int64(s, 1);
-    const char *pRootData = sqlite3_column_blob(s, 2);
-    int nRootData = sqlite3_column_bytes(s, 2);
+  const char *zToken;
+  int nToken;
+  int iStart;
+  int iEnd;
+  int iPos;
 
-    assert( i0 ){
-      leavesReaderDestroy(&pReaders[i]);
-    }
-    return rc;
+  assert( argc==2 || argc==3 );
+
+  nName = sqlite3_value_bytes(argv[0]);
+  zName = (const char *)sqlite3_value_text(argv[0]);
+  nInput = sqlite3_value_bytes(argv[argc-1]);
+  zInput = (const char *)sqlite3_value_text(argv[argc-1]);
+
+  if( argc==3 ){
+    zArg = (const char *)sqlite3_value_text(argv[1]);
   }
 
-  *piReaders = i;
+  pHash = (fts3Hash *)sqlite3_user_data(context);
+  p = (sqlite3_tokenizer_module *)sqlite3Fts3HashFind(pHash, zName, nName+1);
 
-  /* Leave our results sorted by term, then age. */
-  while( i-- ){
-    leavesReaderReorder(pReaders+i, *piReaders-i);
+  if( !p ){
+    char *zErr = sqlite3_mprintf("unknown tokenizer: %s", zName);
+    sqlite3_result_error(context, zErr, -1);
+    sqlite3_free(zErr);
+    return;
   }
-  return SQLITE_OK;
-}
 
-/* Merge doclists from pReaders[nReaders] into a single doclist, which
-** is written to pWriter.  Assumes pReaders is ordered oldest to
-** newest.
-*/
-/* TODO(shess) Consider putting this inline in segmentMerge(). */
-static int leavesReadersMerge(fulltext_vtab *v,
-                              LeavesReader *pReaders, int nReaders,
-                              LeafWriter *pWriter){
-  DLReader dlReaders[MERGE_COUNT];
-  const char *pTerm = leavesReaderTerm(pReaders);
-  int i, nTerm = leavesReaderTermBytes(pReaders);
+  pRet = Tcl_NewObj();
+  Tcl_IncrRefCount(pRet);
 
-  assert( nReaders<=MERGE_COUNT );
+  if( SQLITE_OK!=p->xCreate(zArg ? 1 : 0, &zArg, &pTokenizer) ){
+    zErr = "error in xCreate()";
+    goto finish;
+  }
+  pTokenizer->pModule = p;
+  if( SQLITE_OK!=p->xOpen(pTokenizer, zInput, nInput, &pCsr) ){
+    zErr = "error in xOpen()";
+    goto finish;
+  }
+  pCsr->pTokenizer = pTokenizer;
 
-  for(i=0; ixNext(pCsr, &zToken, &nToken, &iStart, &iEnd, &iPos) ){
+    Tcl_ListObjAppendElement(0, pRet, Tcl_NewIntObj(iPos));
+    Tcl_ListObjAppendElement(0, pRet, Tcl_NewStringObj(zToken, nToken));
+    zToken = &zInput[iStart];
+    nToken = iEnd-iStart;
+    Tcl_ListObjAppendElement(0, pRet, Tcl_NewStringObj(zToken, nToken));
   }
 
-  return leafWriterStepMerge(v, pWriter, pTerm, nTerm, dlReaders, nReaders);
+  if( SQLITE_OK!=p->xClose(pCsr) ){
+    zErr = "error in xClose()";
+    goto finish;
+  }
+  if( SQLITE_OK!=p->xDestroy(pTokenizer) ){
+    zErr = "error in xDestroy()";
+    goto finish;
+  }
+
+finish:
+  if( zErr ){
+    sqlite3_result_error(context, zErr, -1);
+  }else{
+    sqlite3_result_text(context, Tcl_GetString(pRet), -1, SQLITE_TRANSIENT);
+  }
+  Tcl_DecrRefCount(pRet);
 }
 
-/* Forward ref due to mutual recursion with segdirNextIndex(). */
-static int segmentMerge(fulltext_vtab *v, int iLevel);
+static
+int registerTokenizer(
+  sqlite3 *db, 
+  char *zName, 
+  const sqlite3_tokenizer_module *p
+){
+  int rc;
+  sqlite3_stmt *pStmt;
+  const char zSql[] = "SELECT fts3_tokenizer(?, ?)";
 
-/* Put the next available index at iLevel into *pidx.  If iLevel
-** already has MERGE_COUNT segments, they are merged to a higher
-** level to make room.
-*/
-static int segdirNextIndex(fulltext_vtab *v, int iLevel, int *pidx){
-  int rc = segdir_max_index(v, iLevel, pidx);
-  if( rc==SQLITE_DONE ){              /* No segments at iLevel. */
-    *pidx = 0;
-  }else if( rc==SQLITE_ROW ){
-    if( *pidx==(MERGE_COUNT-1) ){
-      rc = segmentMerge(v, iLevel);
-      if( rc!=SQLITE_OK ) return rc;
-      *pidx = 0;
-    }else{
-      (*pidx)++;
-    }
-  }else{
+  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
+  if( rc!=SQLITE_OK ){
     return rc;
   }
-  return SQLITE_OK;
-}
 
-/* Merge MERGE_COUNT segments at iLevel into a new segment at
-** iLevel+1.  If iLevel+1 is already full of segments, those will be
-** merged to make room.
-*/
-static int segmentMerge(fulltext_vtab *v, int iLevel){
-  LeafWriter writer;
-  LeavesReader lrs[MERGE_COUNT];
-  int i, rc, idx = 0;
+  sqlite3_bind_text(pStmt, 1, zName, -1, SQLITE_STATIC);
+  sqlite3_bind_blob(pStmt, 2, &p, sizeof(p), SQLITE_STATIC);
+  sqlite3_step(pStmt);
 
-  /* Determine the next available segment index at the next level,
-  ** merging as necessary.
-  */
-  rc = segdirNextIndex(v, iLevel+1, &idx);
-  if( rc!=SQLITE_OK ) return rc;
+  return sqlite3_finalize(pStmt);
+}
 
-  /* TODO(shess) This assumes that we'll always see exactly
-  ** MERGE_COUNT segments to merge at a given level.  That will be
-  ** broken if we allow the developer to request preemptive or
-  ** deferred merging.
-  */
-  memset(&lrs, '\0', sizeof(lrs));
-  rc = leavesReadersInit(v, iLevel, lrs, &i);
-  if( rc!=SQLITE_OK ) return rc;
-  assert( i==MERGE_COUNT );
+static
+int queryTokenizer(
+  sqlite3 *db, 
+  char *zName,  
+  const sqlite3_tokenizer_module **pp
+){
+  int rc;
+  sqlite3_stmt *pStmt;
+  const char zSql[] = "SELECT fts3_tokenizer(?)";
 
-  leafWriterInit(iLevel+1, idx, &writer);
+  *pp = 0;
+  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
+  if( rc!=SQLITE_OK ){
+    return rc;
+  }
 
-  /* Since leavesReaderReorder() pushes readers at eof to the end,
-  ** when the first reader is empty, all will be empty.
-  */
-  while( !leavesReaderAtEnd(lrs) ){
-    /* Figure out how many readers share their next term. */
-    for(i=1; i0 ){
-      rc = leavesReaderStep(v, lrs+i);
-      if( rc!=SQLITE_OK ) goto err;
+SQLITE_PRIVATE void sqlite3Fts3SimpleTokenizerModule(sqlite3_tokenizer_module const**ppModule);
 
-      /* Reorder by term, then by age. */
-      leavesReaderReorder(lrs+i, MERGE_COUNT-i);
-    }
-  }
+/*
+** Implementation of the scalar function fts3_tokenizer_internal_test().
+** This function is used for testing only, it is not included in the
+** build unless SQLITE_TEST is defined.
+**
+** The purpose of this is to test that the fts3_tokenizer() function
+** can be used as designed by the C-code in the queryTokenizer and
+** registerTokenizer() functions above. These two functions are repeated
+** in the README.tokenizer file as an example, so it is important to
+** test them.
+**
+** To run the tests, evaluate the fts3_tokenizer_internal_test() scalar
+** function with no arguments. An assert() will fail if a problem is
+** detected. i.e.:
+**
+**     SELECT fts3_tokenizer_internal_test();
+**
+*/
+static void intTestFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  int rc;
+  const sqlite3_tokenizer_module *p1;
+  const sqlite3_tokenizer_module *p2;
+  sqlite3 *db = (sqlite3 *)sqlite3_user_data(context);
 
-  for(i=0; i0 );
 
-  for(rc=SQLITE_OK; rc==SQLITE_OK && !leavesReaderAtEnd(pReader);
-      rc=leavesReaderStep(v, pReader)){
-    /* TODO(shess) Really want leavesReaderTermCmp(), but that name is
-    ** already taken to compare the terms of two LeavesReaders.  Think
-    ** on a better name.  [Meanwhile, break encapsulation rather than
-    ** use a confusing name.]
-    */
-    int c = leafReaderTermCmp(&pReader->leafReader, pTerm, nTerm, isPrefix);
-    if( c>0 ) break;      /* Past any possible matches. */
-    if( c==0 ){
-      const char *pData = leavesReaderData(pReader);
-      int iBuffer, nData = leavesReaderDataBytes(pReader);
 
-      /* Find the first empty buffer. */
-      for(iBuffer=0; iBuffer0 ){
-            assert(pBuffers!=NULL);
-            memcpy(p, pBuffers, nBuffers*sizeof(*pBuffers));
-            sqlite3_free(pBuffers);
-          }
-          pBuffers = p;
-        }
-        dataBufferInit(&(pBuffers[nBuffers]), 0);
-        nBuffers++;
-      }
 
-      /* At this point, must have an empty at iBuffer. */
-      assert(iBufferdelim[c];
+}
 
-        /* Handle position 0 specially to avoid need to prime pAcc
-        ** with pData/nData.
-        */
-        dataBufferSwap(p, pAcc);
-        docListAccumulateUnion(pAcc, pData, nData);
+/*
+** Create a new tokenizer instance.
+*/
+static int simpleCreate(
+  int argc, const char * const *argv,
+  sqlite3_tokenizer **ppTokenizer
+){
+  simple_tokenizer *t;
 
-        /* Accumulate remaining doclists into pAcc. */
-        for(++p; ppData, p->nData);
+  t = (simple_tokenizer *) sqlite3_malloc(sizeof(*t));
+  if( t==NULL ) return SQLITE_NOMEM;
+  memset(t, 0, sizeof(*t));
 
-          /* dataBufferReset() could allow a large doclist to blow up
-          ** our memory requirements.
-          */
-          if( p->nCapacity<1024 ){
-            dataBufferReset(p);
-          }else{
-            dataBufferDestroy(p);
-            dataBufferInit(p, 0);
-          }
-        }
+  /* TODO(shess) Delimiters need to remain the same from run to run,
+  ** else we need to reindex.  One solution would be a meta-table to
+  ** track such information in the database, then we'd only want this
+  ** information on the initial create.
+  */
+  if( argc>1 ){
+    int i, n = strlen(argv[1]);
+    for(i=0; i=0x80 ){
+        sqlite3_free(t);
+        return SQLITE_ERROR;
       }
+      t->delim[ch] = 1;
     }
-  }
-
-  /* Union all the doclists together into *out. */
-  /* TODO(shess) What if *out is big?  Sigh. */
-  if( rc==SQLITE_OK && nBuffers>0 ){
-    int iBuffer;
-    for(iBuffer=0; iBuffer0 ){
-        if( out->nData==0 ){
-          dataBufferSwap(out, &(pBuffers[iBuffer]));
-        }else{
-          docListAccumulateUnion(out, pBuffers[iBuffer].pData,
-                                 pBuffers[iBuffer].nData);
-        }
-      }
+  } else {
+    /* Mark non-alphanumeric ASCII characters as delimiters */
+    int i;
+    for(i=1; i<0x80; i++){
+      t->delim[i] = !isalnum(i);
     }
   }
 
-  while( nBuffers-- ){
-    dataBufferDestroy(&(pBuffers[nBuffers]));
-  }
-  if( pBuffers!=NULL ) sqlite3_free(pBuffers);
-
-  return rc;
+  *ppTokenizer = &t->base;
+  return SQLITE_OK;
 }
 
-/* Call loadSegmentLeavesInt() with pData/nData as input. */
-static int loadSegmentLeaf(fulltext_vtab *v, const char *pData, int nData,
-                           const char *pTerm, int nTerm, int isPrefix,
-                           DataBuffer *out){
-  LeavesReader reader;
-  int rc;
-
-  assert( nData>1 );
-  assert( *pData=='\0' );
-  rc = leavesReaderInit(v, 0, 0, 0, pData, nData, &reader);
-  if( rc!=SQLITE_OK ) return rc;
-
-  rc = loadSegmentLeavesInt(v, &reader, pTerm, nTerm, isPrefix, out);
-  leavesReaderReset(&reader);
-  leavesReaderDestroy(&reader);
-  return rc;
+/*
+** Destroy a tokenizer
+*/
+static int simpleDestroy(sqlite3_tokenizer *pTokenizer){
+  sqlite3_free(pTokenizer);
+  return SQLITE_OK;
 }
 
-/* Call loadSegmentLeavesInt() with the leaf nodes from iStartLeaf to
-** iEndLeaf (inclusive) as input, and merge the resulting doclist into
-** out.
+/*
+** Prepare to begin tokenizing a particular string.  The input
+** string to be tokenized is pInput[0..nBytes-1].  A cursor
+** used to incrementally tokenize this string is returned in 
+** *ppCursor.
 */
-static int loadSegmentLeaves(fulltext_vtab *v,
-                             sqlite_int64 iStartLeaf, sqlite_int64 iEndLeaf,
-                             const char *pTerm, int nTerm, int isPrefix,
-                             DataBuffer *out){
-  int rc;
-  LeavesReader reader;
+static int simpleOpen(
+  sqlite3_tokenizer *pTokenizer,         /* The tokenizer */
+  const char *pInput, int nBytes,        /* String to be tokenized */
+  sqlite3_tokenizer_cursor **ppCursor    /* OUT: Tokenization cursor */
+){
+  simple_tokenizer_cursor *c;
 
-  assert( iStartLeaf<=iEndLeaf );
-  rc = leavesReaderInit(v, 0, iStartLeaf, iEndLeaf, NULL, 0, &reader);
-  if( rc!=SQLITE_OK ) return rc;
+  c = (simple_tokenizer_cursor *) sqlite3_malloc(sizeof(*c));
+  if( c==NULL ) return SQLITE_NOMEM;
 
-  rc = loadSegmentLeavesInt(v, &reader, pTerm, nTerm, isPrefix, out);
-  leavesReaderReset(&reader);
-  leavesReaderDestroy(&reader);
-  return rc;
+  c->pInput = pInput;
+  if( pInput==0 ){
+    c->nBytes = 0;
+  }else if( nBytes<0 ){
+    c->nBytes = (int)strlen(pInput);
+  }else{
+    c->nBytes = nBytes;
+  }
+  c->iOffset = 0;                 /* start tokenizing at the beginning */
+  c->iToken = 0;
+  c->pToken = NULL;               /* no space allocated, yet. */
+  c->nTokenAllocated = 0;
+
+  *ppCursor = &c->base;
+  return SQLITE_OK;
 }
 
-/* Taking pData/nData as an interior node, find the sequence of child
-** nodes which could include pTerm/nTerm/isPrefix.  Note that the
-** interior node terms logically come between the blocks, so there is
-** one more blockid than there are terms (that block contains terms >=
-** the last interior-node term).
+/*
+** Close a tokenization cursor previously opened by a call to
+** simpleOpen() above.
 */
-/* TODO(shess) The calling code may already know that the end child is
-** not worth calculating, because the end may be in a later sibling
-** node.  Consider whether breaking symmetry is worthwhile.  I suspect
-** it is not worthwhile.
+static int simpleClose(sqlite3_tokenizer_cursor *pCursor){
+  simple_tokenizer_cursor *c = (simple_tokenizer_cursor *) pCursor;
+  sqlite3_free(c->pToken);
+  sqlite3_free(c);
+  return SQLITE_OK;
+}
+
+/*
+** Extract the next token from a tokenization cursor.  The cursor must
+** have been opened by a prior call to simpleOpen().
 */
-static void getChildrenContaining(const char *pData, int nData,
-                                  const char *pTerm, int nTerm, int isPrefix,
-                                  sqlite_int64 *piStartChild,
-                                  sqlite_int64 *piEndChild){
-  InteriorReader reader;
+static int simpleNext(
+  sqlite3_tokenizer_cursor *pCursor,  /* Cursor returned by simpleOpen */
+  const char **ppToken,               /* OUT: *ppToken is the token text */
+  int *pnBytes,                       /* OUT: Number of bytes in token */
+  int *piStartOffset,                 /* OUT: Starting offset of token */
+  int *piEndOffset,                   /* OUT: Ending offset of token */
+  int *piPosition                     /* OUT: Position integer of token */
+){
+  simple_tokenizer_cursor *c = (simple_tokenizer_cursor *) pCursor;
+  simple_tokenizer *t = (simple_tokenizer *) pCursor->pTokenizer;
+  unsigned char *p = (unsigned char *)c->pInput;
 
-  assert( nData>1 );
-  assert( *pData!='\0' );
-  interiorReaderInit(pData, nData, &reader);
+  while( c->iOffsetnBytes ){
+    int iStartOffset;
 
-  /* Scan for the first child which could contain pTerm/nTerm. */
-  while( !interiorReaderAtEnd(&reader) ){
-    if( interiorReaderTermCmp(&reader, pTerm, nTerm, 0)>0 ) break;
-    interiorReaderStep(&reader);
-  }
-  *piStartChild = interiorReaderCurrentBlockid(&reader);
+    /* Scan past delimiter characters */
+    while( c->iOffsetnBytes && simpleDelim(t, p[c->iOffset]) ){
+      c->iOffset++;
+    }
 
-  /* Keep scanning to find a term greater than our term, using prefix
-  ** comparison if indicated.  If isPrefix is false, this will be the
-  ** same blockid as the starting block.
-  */
-  while( !interiorReaderAtEnd(&reader) ){
-    if( interiorReaderTermCmp(&reader, pTerm, nTerm, isPrefix)>0 ) break;
-    interiorReaderStep(&reader);
-  }
-  *piEndChild = interiorReaderCurrentBlockid(&reader);
+    /* Count non-delimiter characters. */
+    iStartOffset = c->iOffset;
+    while( c->iOffsetnBytes && !simpleDelim(t, p[c->iOffset]) ){
+      c->iOffset++;
+    }
 
-  interiorReaderDestroy(&reader);
+    if( c->iOffset>iStartOffset ){
+      int i, n = c->iOffset-iStartOffset;
+      if( n>c->nTokenAllocated ){
+        c->nTokenAllocated = n+20;
+        c->pToken = sqlite3_realloc(c->pToken, c->nTokenAllocated);
+        if( c->pToken==NULL ) return SQLITE_NOMEM;
+      }
+      for(i=0; ipToken[i] = ch<0x80 ? tolower(ch) : ch;
+      }
+      *ppToken = c->pToken;
+      *pnBytes = n;
+      *piStartOffset = iStartOffset;
+      *piEndOffset = c->iOffset;
+      *piPosition = c->iToken++;
 
-  /* Children must ascend, and if !prefix, both must be the same. */
-  assert( *piEndChild>=*piStartChild );
-  assert( isPrefix || *piStartChild==*piEndChild );
+      return SQLITE_OK;
+    }
+  }
+  return SQLITE_DONE;
 }
 
-/* Read block at iBlockid and pass it with other params to
-** getChildrenContaining().
+/*
+** The set of routines that implement the simple tokenizer
 */
-static int loadAndGetChildrenContaining(
-  fulltext_vtab *v,
-  sqlite_int64 iBlockid,
-  const char *pTerm, int nTerm, int isPrefix,
-  sqlite_int64 *piStartChild, sqlite_int64 *piEndChild
+static const sqlite3_tokenizer_module simpleTokenizerModule = {
+  0,
+  simpleCreate,
+  simpleDestroy,
+  simpleOpen,
+  simpleClose,
+  simpleNext,
+};
+
+/*
+** Allocate a new simple tokenizer.  Return a pointer to the new
+** tokenizer in *ppModule
+*/
+SQLITE_PRIVATE void sqlite3Fts3SimpleTokenizerModule(
+  sqlite3_tokenizer_module const**ppModule
 ){
-  sqlite3_stmt *s = NULL;
-  int rc;
+  *ppModule = &simpleTokenizerModule;
+}
 
-  assert( iBlockid!=0 );
-  assert( pTerm!=NULL );
-  assert( nTerm!=0 );        /* TODO(shess) Why not allow this? */
-  assert( piStartChild!=NULL );
-  assert( piEndChild!=NULL );
+#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
 
-  rc = sql_get_statement(v, BLOCK_SELECT_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+/************** End of fts3_tokenizer1.c *************************************/
+/************** Begin file rtree.c *******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains code for implementations of the r-tree and r*-tree
+** algorithms packaged as an SQLite virtual table module.
+**
+** $Id: rtree.c,v 1.9 2008/09/08 11:07:03 danielk1977 Exp $
+*/
 
-  rc = sqlite3_bind_int64(s, 1, iBlockid);
-  if( rc!=SQLITE_OK ) return rc;
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_RTREE)
 
-  rc = sqlite3_step(s);
-  if( rc==SQLITE_DONE ) return SQLITE_ERROR;
-  if( rc!=SQLITE_ROW ) return rc;
+/*
+** This file contains an implementation of a couple of different variants
+** of the r-tree algorithm. See the README file for further details. The 
+** same data-structure is used for all, but the algorithms for insert and
+** delete operations vary. The variants used are selected at compile time 
+** by defining the following symbols:
+*/
 
-  getChildrenContaining(sqlite3_column_blob(s, 0), sqlite3_column_bytes(s, 0),
-                        pTerm, nTerm, isPrefix, piStartChild, piEndChild);
+/* Either, both or none of the following may be set to activate 
+** r*tree variant algorithms.
+*/
+#define VARIANT_RSTARTREE_CHOOSESUBTREE 0
+#define VARIANT_RSTARTREE_REINSERT      1
 
-  /* We expect only one row.  We must execute another sqlite3_step()
-   * to complete the iteration; otherwise the table will remain
-   * locked. */
-  rc = sqlite3_step(s);
-  if( rc==SQLITE_ROW ) return SQLITE_ERROR;
-  if( rc!=SQLITE_DONE ) return rc;
+/* 
+** Exactly one of the following must be set to 1.
+*/
+#define VARIANT_GUTTMAN_QUADRATIC_SPLIT 0
+#define VARIANT_GUTTMAN_LINEAR_SPLIT    0
+#define VARIANT_RSTARTREE_SPLIT         1
 
-  return SQLITE_OK;
-}
+#define VARIANT_GUTTMAN_SPLIT \
+        (VARIANT_GUTTMAN_LINEAR_SPLIT||VARIANT_GUTTMAN_QUADRATIC_SPLIT)
 
-/* Traverse the tree represented by pData[nData] looking for
-** pTerm[nTerm], placing its doclist into *out.  This is internal to
-** loadSegment() to make error-handling cleaner.
-*/
-static int loadSegmentInt(fulltext_vtab *v, const char *pData, int nData,
-                          sqlite_int64 iLeavesEnd,
-                          const char *pTerm, int nTerm, int isPrefix,
-                          DataBuffer *out){
-  /* Special case where root is a leaf. */
-  if( *pData=='\0' ){
-    return loadSegmentLeaf(v, pData, nData, pTerm, nTerm, isPrefix, out);
-  }else{
-    int rc;
-    sqlite_int64 iStartChild, iEndChild;
+#if VARIANT_GUTTMAN_QUADRATIC_SPLIT
+  #define PickNext QuadraticPickNext
+  #define PickSeeds QuadraticPickSeeds
+  #define AssignCells splitNodeGuttman
+#endif
+#if VARIANT_GUTTMAN_LINEAR_SPLIT
+  #define PickNext LinearPickNext
+  #define PickSeeds LinearPickSeeds
+  #define AssignCells splitNodeGuttman
+#endif
+#if VARIANT_RSTARTREE_SPLIT
+  #define AssignCells splitNodeStartree
+#endif
 
-    /* Process pData as an interior node, then loop down the tree
-    ** until we find the set of leaf nodes to scan for the term.
-    */
-    getChildrenContaining(pData, nData, pTerm, nTerm, isPrefix,
-                          &iStartChild, &iEndChild);
-    while( iStartChild>iLeavesEnd ){
-      sqlite_int64 iNextStart, iNextEnd;
-      rc = loadAndGetChildrenContaining(v, iStartChild, pTerm, nTerm, isPrefix,
-                                        &iNextStart, &iNextEnd);
-      if( rc!=SQLITE_OK ) return rc;
 
-      /* If we've branched, follow the end branch, too. */
-      if( iStartChild!=iEndChild ){
-        sqlite_int64 iDummy;
-        rc = loadAndGetChildrenContaining(v, iEndChild, pTerm, nTerm, isPrefix,
-                                          &iDummy, &iNextEnd);
-        if( rc!=SQLITE_OK ) return rc;
-      }
+#ifndef SQLITE_CORE
+  SQLITE_EXTENSION_INIT1
+#else
+#endif
 
-      assert( iNextStart<=iNextEnd );
-      iStartChild = iNextStart;
-      iEndChild = iNextEnd;
-    }
-    assert( iStartChild<=iLeavesEnd );
-    assert( iEndChild<=iLeavesEnd );
 
-    /* Scan through the leaf segments for doclists. */
-    return loadSegmentLeaves(v, iStartChild, iEndChild,
-                             pTerm, nTerm, isPrefix, out);
-  }
-}
+#ifndef SQLITE_AMALGAMATION
+typedef sqlite3_int64 i64;
+typedef unsigned char u8;
+typedef unsigned int u32;
+#endif
 
-/* Call loadSegmentInt() to collect the doclist for pTerm/nTerm, then
-** merge its doclist over *out (any duplicate doclists read from the
-** segment rooted at pData will overwrite those in *out).
-*/
-/* TODO(shess) Consider changing this to determine the depth of the
-** leaves using either the first characters of interior nodes (when
-** ==1, we're one level above the leaves), or the first character of
-** the root (which will describe the height of the tree directly).
-** Either feels somewhat tricky to me.
-*/
-/* TODO(shess) The current merge is likely to be slow for large
-** doclists (though it should process from newest/smallest to
-** oldest/largest, so it may not be that bad).  It might be useful to
-** modify things to allow for N-way merging.  This could either be
-** within a segment, with pairwise merges across segments, or across
-** all segments at once.
-*/
-static int loadSegment(fulltext_vtab *v, const char *pData, int nData,
-                       sqlite_int64 iLeavesEnd,
-                       const char *pTerm, int nTerm, int isPrefix,
-                       DataBuffer *out){
-  DataBuffer result;
-  int rc;
+typedef struct Rtree Rtree;
+typedef struct RtreeCursor RtreeCursor;
+typedef struct RtreeNode RtreeNode;
+typedef struct RtreeCell RtreeCell;
+typedef struct RtreeConstraint RtreeConstraint;
+typedef union RtreeCoord RtreeCoord;
 
-  assert( nData>1 );
+/* The rtree may have between 1 and RTREE_MAX_DIMENSIONS dimensions. */
+#define RTREE_MAX_DIMENSIONS 5
 
-  /* This code should never be called with buffered updates. */
-  assert( v->nPendingData<0 );
+/* Size of hash table Rtree.aHash. This hash table is not expected to
+** ever contain very many entries, so a fixed number of buckets is 
+** used.
+*/
+#define HASHSIZE 128
 
-  dataBufferInit(&result, 0);
-  rc = loadSegmentInt(v, pData, nData, iLeavesEnd,
-                      pTerm, nTerm, isPrefix, &result);
-  if( rc==SQLITE_OK && result.nData>0 ){
-    if( out->nData==0 ){
-      DataBuffer tmp = *out;
-      *out = result;
-      result = tmp;
-    }else{
-      DataBuffer merged;
-      DLReader readers[2];
+/* 
+** An rtree virtual-table object.
+*/
+struct Rtree {
+  sqlite3_vtab base;
+  sqlite3 *db;                /* Host database connection */
+  int iNodeSize;              /* Size in bytes of each node in the node table */
+  int nDim;                   /* Number of dimensions */
+  int nBytesPerCell;          /* Bytes consumed per cell */
+  int iDepth;                 /* Current depth of the r-tree structure */
+  char *zDb;                  /* Name of database containing r-tree table */
+  char *zName;                /* Name of r-tree table */ 
+  RtreeNode *aHash[HASHSIZE]; /* Hash table of in-memory nodes. */ 
+  int nBusy;                  /* Current number of users of this structure */
+
+  /* List of nodes removed during a CondenseTree operation. List is
+  ** linked together via the pointer normally used for hash chains -
+  ** RtreeNode.pNext. RtreeNode.iNode stores the depth of the sub-tree 
+  ** headed by the node (leaf nodes have RtreeNode.iNode==0).
+  */
+  RtreeNode *pDeleted;
+  int iReinsertHeight;        /* Height of sub-trees Reinsert() has run on */
+
+  /* Statements to read/write/delete a record from xxx_node */
+  sqlite3_stmt *pReadNode;
+  sqlite3_stmt *pWriteNode;
+  sqlite3_stmt *pDeleteNode;
+
+  /* Statements to read/write/delete a record from xxx_rowid */
+  sqlite3_stmt *pReadRowid;
+  sqlite3_stmt *pWriteRowid;
+  sqlite3_stmt *pDeleteRowid;
+
+  /* Statements to read/write/delete a record from xxx_parent */
+  sqlite3_stmt *pReadParent;
+  sqlite3_stmt *pWriteParent;
+  sqlite3_stmt *pDeleteParent;
+
+  int eCoordType;
+};
 
-      dlrInit(&readers[0], DL_DEFAULT, out->pData, out->nData);
-      dlrInit(&readers[1], DL_DEFAULT, result.pData, result.nData);
-      dataBufferInit(&merged, out->nData+result.nData);
-      docListMerge(&merged, readers, 2);
-      dataBufferDestroy(out);
-      *out = merged;
-      dlrDestroy(&readers[0]);
-      dlrDestroy(&readers[1]);
-    }
-  }
-  dataBufferDestroy(&result);
-  return rc;
-}
+/* Possible values for eCoordType: */
+#define RTREE_COORD_REAL32 0
+#define RTREE_COORD_INT32  1
 
-/* Scan the database and merge together the posting lists for the term
-** into *out.
+/*
+** The minimum number of cells allowed for a node is a third of the 
+** maximum. In Gutman's notation:
+**
+**     m = M/3
+**
+** If an R*-tree "Reinsert" operation is required, the same number of
+** cells are removed from the overfull node and reinserted into the tree.
 */
-static int termSelect(fulltext_vtab *v, int iColumn,
-                      const char *pTerm, int nTerm, int isPrefix,
-                      DocListType iType, DataBuffer *out){
-  DataBuffer doclist;
-  sqlite3_stmt *s;
-  int rc = sql_get_statement(v, SEGDIR_SELECT_ALL_STMT, &s);
-  if( rc!=SQLITE_OK ) return rc;
+#define RTREE_MINCELLS(p) ((((p)->iNodeSize-4)/(p)->nBytesPerCell)/3)
+#define RTREE_REINSERT(p) RTREE_MINCELLS(p)
+#define RTREE_MAXCELLS 51
 
-  /* This code should never be called with buffered updates. */
-  assert( v->nPendingData<0 );
+/* 
+** An rtree cursor object.
+*/
+struct RtreeCursor {
+  sqlite3_vtab_cursor base;
+  RtreeNode *pNode;                 /* Node cursor is currently pointing at */
+  int iCell;                        /* Index of current cell in pNode */
+  int iStrategy;                    /* Copy of idxNum search parameter */
+  int nConstraint;                  /* Number of entries in aConstraint */
+  RtreeConstraint *aConstraint;     /* Search constraints. */
+};
 
-  dataBufferInit(&doclist, 0);
+union RtreeCoord {
+  float f;
+  int i;
+};
 
-  /* Traverse the segments from oldest to newest so that newer doclist
-  ** elements for given docids overwrite older elements.
-  */
-  while( (rc = sqlite3_step(s))==SQLITE_ROW ){
-    const char *pData = sqlite3_column_blob(s, 0);
-    const int nData = sqlite3_column_bytes(s, 0);
-    const sqlite_int64 iLeavesEnd = sqlite3_column_int64(s, 1);
-    rc = loadSegment(v, pData, nData, iLeavesEnd, pTerm, nTerm, isPrefix,
-                     &doclist);
-    if( rc!=SQLITE_OK ) goto err;
-  }
-  if( rc==SQLITE_DONE ){
-    if( doclist.nData!=0 ){
-      /* TODO(shess) The old term_select_all() code applied the column
-      ** restrict as we merged segments, leading to smaller buffers.
-      ** This is probably worthwhile to bring back, once the new storage
-      ** system is checked in.
-      */
-      if( iColumn==v->nColumn) iColumn = -1;
-      docListTrim(DL_DEFAULT, doclist.pData, doclist.nData,
-                  iColumn, iType, out);
-    }
-    rc = SQLITE_OK;
-  }
+/*
+** The argument is an RtreeCoord. Return the value stored within the RtreeCoord
+** formatted as a double. This macro assumes that local variable pRtree points
+** to the Rtree structure associated with the RtreeCoord.
+*/
+#define DCOORD(coord) (                           \
+  (pRtree->eCoordType==RTREE_COORD_REAL32) ?      \
+    ((double)coord.f) :                           \
+    ((double)coord.i)                             \
+)
 
- err:
-  dataBufferDestroy(&doclist);
-  return rc;
-}
+/*
+** A search constraint.
+*/
+struct RtreeConstraint {
+  int iCoord;                       /* Index of constrained coordinate */
+  int op;                           /* Constraining operation */
+  double rValue;                    /* Constraint value. */
+};
 
-/****************************************************************/
-/* Used to hold hashtable data for sorting. */
-typedef struct TermData {
-  const char *pTerm;
-  int nTerm;
-  DLCollector *pCollector;
-} TermData;
+/* Possible values for RtreeConstraint.op */
+#define RTREE_EQ 0x41
+#define RTREE_LE 0x42
+#define RTREE_LT 0x43
+#define RTREE_GE 0x44
+#define RTREE_GT 0x45
 
-/* Orders TermData elements in strcmp fashion ( <0 for less-than, 0
-** for equal, >0 for greater-than).
+/* 
+** An rtree structure node.
+**
+** Data format (RtreeNode.zData):
+**
+**   1. If the node is the root node (node 1), then the first 2 bytes
+**      of the node contain the tree depth as a big-endian integer.
+**      For non-root nodes, the first 2 bytes are left unused.
+**
+**   2. The next 2 bytes contain the number of entries currently 
+**      stored in the node.
+**
+**   3. The remainder of the node contains the node entries. Each entry
+**      consists of a single 8-byte integer followed by an even number
+**      of 4-byte coordinates. For leaf nodes the integer is the rowid
+**      of a record. For internal nodes it is the node number of a
+**      child page.
 */
-static int termDataCmp(const void *av, const void *bv){
-  const TermData *a = (const TermData *)av;
-  const TermData *b = (const TermData *)bv;
-  int n = a->nTermnTerm ? a->nTerm : b->nTerm;
-  int c = memcmp(a->pTerm, b->pTerm, n);
-  if( c!=0 ) return c;
-  return a->nTerm-b->nTerm;
-}
+struct RtreeNode {
+  RtreeNode *pParent;               /* Parent node */
+  i64 iNode;
+  int nRef;
+  int isDirty;
+  u8 *zData;
+  RtreeNode *pNext;                 /* Next node in this hash chain */
+};
+#define NCELL(pNode) readInt16(&(pNode)->zData[2])
 
-/* Order pTerms data by term, then write a new level 0 segment using
-** LeafWriter.
+/* 
+** Structure to store a deserialized rtree record.
 */
-static int writeZeroSegment(fulltext_vtab *v, fts3Hash *pTerms){
-  fts3HashElem *e;
-  int idx, rc, i, n;
-  TermData *pData;
-  LeafWriter writer;
-  DataBuffer dl;
+struct RtreeCell {
+  i64 iRowid;
+  RtreeCoord aCoord[RTREE_MAX_DIMENSIONS*2];
+};
 
-  /* Determine the next index at level 0, merging as necessary. */
-  rc = segdirNextIndex(v, 0, &idx);
-  if( rc!=SQLITE_OK ) return rc;
+#define MAX(x,y) ((x) < (y) ? (y) : (x))
+#define MIN(x,y) ((x) > (y) ? (y) : (x))
 
-  n = fts3HashCount(pTerms);
-  pData = sqlite3_malloc(n*sizeof(TermData));
+/*
+** Functions to deserialize a 16 bit integer, 32 bit real number and
+** 64 bit integer. The deserialized value is returned.
+*/
+static int readInt16(u8 *p){
+  return (p[0]<<8) + p[1];
+}
+static void readCoord(u8 *p, RtreeCoord *pCoord){
+  u32 i = (
+    (((u32)p[0]) << 24) + 
+    (((u32)p[1]) << 16) + 
+    (((u32)p[2]) <<  8) + 
+    (((u32)p[3]) <<  0)
+  );
+  *(u32 *)pCoord = i;
+}
+static i64 readInt64(u8 *p){
+  return (
+    (((i64)p[0]) << 56) + 
+    (((i64)p[1]) << 48) + 
+    (((i64)p[2]) << 40) + 
+    (((i64)p[3]) << 32) + 
+    (((i64)p[4]) << 24) + 
+    (((i64)p[5]) << 16) + 
+    (((i64)p[6]) <<  8) + 
+    (((i64)p[7]) <<  0)
+  );
+}
 
-  for(i = 0, e = fts3HashFirst(pTerms); e; i++, e = fts3HashNext(e)){
-    assert( i> 8)&0xFF;
+  p[1] = (i>> 0)&0xFF;
+  return 2;
+}
+static int writeCoord(u8 *p, RtreeCoord *pCoord){
+  u32 i;
+  assert( sizeof(RtreeCoord)==4 );
+  assert( sizeof(u32)==4 );
+  i = *(u32 *)pCoord;
+  p[0] = (i>>24)&0xFF;
+  p[1] = (i>>16)&0xFF;
+  p[2] = (i>> 8)&0xFF;
+  p[3] = (i>> 0)&0xFF;
+  return 4;
+}
+static int writeInt64(u8 *p, i64 i){
+  p[0] = (i>>56)&0xFF;
+  p[1] = (i>>48)&0xFF;
+  p[2] = (i>>40)&0xFF;
+  p[3] = (i>>32)&0xFF;
+  p[4] = (i>>24)&0xFF;
+  p[5] = (i>>16)&0xFF;
+  p[6] = (i>> 8)&0xFF;
+  p[7] = (i>> 0)&0xFF;
+  return 8;
+}
+
+/*
+** Increment the reference count of node p.
+*/
+static void nodeReference(RtreeNode *p){
+  if( p ){
+    p->nRef++;
   }
-  assert( i==n );
-
-  /* TODO(shess) Should we allow user-defined collation sequences,
-  ** here?  I think we only need that once we support prefix searches.
-  */
-  if( n>1 ) qsort(pData, n, sizeof(*pData), termDataCmp);
+}
 
-  /* TODO(shess) Refactor so that we can write directly to the segment
-  ** DataBuffer, as happens for segment merges.
-  */
-  leafWriterInit(0, idx, &writer);
-  dataBufferInit(&dl, 0);
-  for(i=0; izData[2], 0, pRtree->iNodeSize-2);
+    p->isDirty = 1;
   }
-  rc = leafWriterFinalize(v, &writer);
+}
 
- err:
-  dataBufferDestroy(&dl);
-  sqlite3_free(pData);
-  leafWriterDestroy(&writer);
-  return rc;
+/*
+** Given a node number iNode, return the corresponding key to use
+** in the Rtree.aHash table.
+*/
+static int nodeHash(i64 iNode){
+  return (
+    (iNode>>56) ^ (iNode>>48) ^ (iNode>>40) ^ (iNode>>32) ^ 
+    (iNode>>24) ^ (iNode>>16) ^ (iNode>> 8) ^ (iNode>> 0)
+  ) % HASHSIZE;
 }
 
-/* If pendingTerms has data, free it. */
-static int clearPendingTerms(fulltext_vtab *v){
-  if( v->nPendingData>=0 ){
-    fts3HashElem *e;
-    for(e=fts3HashFirst(&v->pendingTerms); e; e=fts3HashNext(e)){
-      dlcDelete(fts3HashData(e));
-    }
-    fts3HashClear(&v->pendingTerms);
-    v->nPendingData = -1;
-  }
-  return SQLITE_OK;
+/*
+** Search the node hash table for node iNode. If found, return a pointer
+** to it. Otherwise, return 0.
+*/
+static RtreeNode *nodeHashLookup(Rtree *pRtree, i64 iNode){
+  RtreeNode *p;
+  assert( iNode!=0 );
+  for(p=pRtree->aHash[nodeHash(iNode)]; p && p->iNode!=iNode; p=p->pNext);
+  return p;
 }
 
-/* If pendingTerms has data, flush it to a level-zero segment, and
-** free it.
+/*
+** Add node pNode to the node hash table.
 */
-static int flushPendingTerms(fulltext_vtab *v){
-  if( v->nPendingData>=0 ){
-    int rc = writeZeroSegment(v, &v->pendingTerms);
-    if( rc==SQLITE_OK ) clearPendingTerms(v);
-    return rc;
+static void nodeHashInsert(Rtree *pRtree, RtreeNode *pNode){
+  if( pNode ){
+    int iHash;
+    assert( pNode->pNext==0 );
+    iHash = nodeHash(pNode->iNode);
+    pNode->pNext = pRtree->aHash[iHash];
+    pRtree->aHash[iHash] = pNode;
   }
-  return SQLITE_OK;
 }
 
-/* If pendingTerms is "too big", or docid is out of order, flush it.
-** Regardless, be certain that pendingTerms is initialized for use.
+/*
+** Remove node pNode from the node hash table.
 */
-static int initPendingTerms(fulltext_vtab *v, sqlite_int64 iDocid){
-  /* TODO(shess) Explore whether partially flushing the buffer on
-  ** forced-flush would provide better performance.  I suspect that if
-  ** we ordered the doclists by size and flushed the largest until the
-  ** buffer was half empty, that would let the less frequent terms
-  ** generate longer doclists.
-  */
-  if( iDocid<=v->iPrevDocid || v->nPendingData>kPendingThreshold ){
-    int rc = flushPendingTerms(v);
-    if( rc!=SQLITE_OK ) return rc;
+static void nodeHashDelete(Rtree *pRtree, RtreeNode *pNode){
+  RtreeNode **pp;
+  if( pNode->iNode!=0 ){
+    pp = &pRtree->aHash[nodeHash(pNode->iNode)];
+    for( ; (*pp)!=pNode; pp = &(*pp)->pNext){ assert(*pp); }
+    *pp = pNode->pNext;
+    pNode->pNext = 0;
   }
-  if( v->nPendingData<0 ){
-    fts3HashInit(&v->pendingTerms, FTS3_HASH_STRING, 1);
-    v->nPendingData = 0;
+}
+
+/*
+** Allocate and return new r-tree node. Initially, (RtreeNode.iNode==0),
+** indicating that node has not yet been assigned a node number. It is
+** assigned a node number when nodeWrite() is called to write the
+** node contents out to the database.
+*/
+static RtreeNode *nodeNew(Rtree *pRtree, RtreeNode *pParent, int zero){
+  RtreeNode *pNode;
+  pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode) + pRtree->iNodeSize);
+  if( pNode ){
+    memset(pNode, 0, sizeof(RtreeNode) + (zero?pRtree->iNodeSize:0));
+    pNode->zData = (u8 *)&pNode[1];
+    pNode->nRef = 1;
+    pNode->pParent = pParent;
+    pNode->isDirty = 1;
+    nodeReference(pParent);
   }
-  v->iPrevDocid = iDocid;
-  return SQLITE_OK;
+  return pNode;
 }
 
-/* This function implements the xUpdate callback; it is the top-level entry
- * point for inserting, deleting or updating a row in a full-text table. */
-static int fulltextUpdate(sqlite3_vtab *pVtab, int nArg, sqlite3_value **ppArg,
-                          sqlite_int64 *pRowid){
-  fulltext_vtab *v = (fulltext_vtab *) pVtab;
+/*
+** Obtain a reference to an r-tree node.
+*/
+static int
+nodeAcquire(
+  Rtree *pRtree,             /* R-tree structure */
+  i64 iNode,                 /* Node number to load */
+  RtreeNode *pParent,        /* Either the parent node or NULL */
+  RtreeNode **ppNode         /* OUT: Acquired node */
+){
   int rc;
+  RtreeNode *pNode;
 
-  FTSTRACE(("FTS3 Update %p\n", pVtab));
-
-  if( nArg<2 ){
-    rc = index_delete(v, sqlite3_value_int64(ppArg[0]));
-  } else if( sqlite3_value_type(ppArg[0]) != SQLITE_NULL ){
-    /* An update:
-     * ppArg[0] = old rowid
-     * ppArg[1] = new rowid
-     * ppArg[2..2+v->nColumn-1] = values
-     * ppArg[2+v->nColumn] = value for magic column (we ignore this)
-     * ppArg[2+v->nColumn+1] = value for docid
-     */
-    sqlite_int64 rowid = sqlite3_value_int64(ppArg[0]);
-    if( sqlite3_value_type(ppArg[1]) != SQLITE_INTEGER ||
-        sqlite3_value_int64(ppArg[1]) != rowid ){
-      rc = SQLITE_ERROR;  /* we don't allow changing the rowid */
-    }else if( sqlite3_value_type(ppArg[2+v->nColumn+1]) != SQLITE_INTEGER ||
-              sqlite3_value_int64(ppArg[2+v->nColumn+1]) != rowid ){
-      rc = SQLITE_ERROR;  /* we don't allow changing the docid */
-    }else{
-      assert( nArg==2+v->nColumn+2);
-      rc = index_update(v, rowid, &ppArg[2]);
-    }
-  } else {
-    /* An insert:
-     * ppArg[1] = requested rowid
-     * ppArg[2..2+v->nColumn-1] = values
-     * ppArg[2+v->nColumn] = value for magic column (we ignore this)
-     * ppArg[2+v->nColumn+1] = value for docid
-     */
-    sqlite3_value *pRequestDocid = ppArg[2+v->nColumn+1];
-    assert( nArg==2+v->nColumn+2);
-    if( SQLITE_NULL != sqlite3_value_type(pRequestDocid) &&
-        SQLITE_NULL != sqlite3_value_type(ppArg[1]) ){
-      /* TODO(shess) Consider allowing this to work if the values are
-      ** identical.  I'm inclined to discourage that usage, though,
-      ** given that both rowid and docid are special columns.  Better
-      ** would be to define one or the other as the default winner,
-      ** but should it be fts3-centric (docid) or SQLite-centric
-      ** (rowid)?
-      */
-      rc = SQLITE_ERROR;
-    }else{
-      if( SQLITE_NULL == sqlite3_value_type(pRequestDocid) ){
-        pRequestDocid = ppArg[1];
-      }
-      rc = index_insert(v, pRequestDocid, &ppArg[2], pRowid);
+  /* Check if the requested node is already in the hash table. If so,
+  ** increase its reference count and return it.
+  */
+  if( (pNode = nodeHashLookup(pRtree, iNode)) ){
+    assert( !pParent || !pNode->pParent || pNode->pParent==pParent );
+    if( pParent ){
+      pNode->pParent = pParent;
     }
+    pNode->nRef++;
+    *ppNode = pNode;
+    return SQLITE_OK;
+  }
+
+  pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode) + pRtree->iNodeSize);
+  if( !pNode ){
+    *ppNode = 0;
+    return SQLITE_NOMEM;
+  }
+  pNode->pParent = pParent;
+  pNode->zData = (u8 *)&pNode[1];
+  pNode->nRef = 1;
+  pNode->iNode = iNode;
+  pNode->isDirty = 0;
+  pNode->pNext = 0;
+
+  sqlite3_bind_int64(pRtree->pReadNode, 1, iNode);
+  rc = sqlite3_step(pRtree->pReadNode);
+  if( rc==SQLITE_ROW ){
+    const u8 *zBlob = sqlite3_column_blob(pRtree->pReadNode, 0);
+    memcpy(pNode->zData, zBlob, pRtree->iNodeSize);
+    nodeReference(pParent);
+  }else{
+    sqlite3_free(pNode);
+    pNode = 0;
+  }
+
+  *ppNode = pNode;
+  rc = sqlite3_reset(pRtree->pReadNode);
+
+  if( rc==SQLITE_OK && iNode==1 ){
+    pRtree->iDepth = readInt16(pNode->zData);
   }
 
+  assert( (rc==SQLITE_OK && pNode) || (pNode==0 && rc!=SQLITE_OK) );
+  nodeHashInsert(pRtree, pNode);
+
   return rc;
 }
 
-static int fulltextSync(sqlite3_vtab *pVtab){
-  FTSTRACE(("FTS3 xSync()\n"));
-  return flushPendingTerms((fulltext_vtab *)pVtab);
+/*
+** Overwrite cell iCell of node pNode with the contents of pCell.
+*/
+static void nodeOverwriteCell(
+  Rtree *pRtree, 
+  RtreeNode *pNode,  
+  RtreeCell *pCell, 
+  int iCell
+){
+  int ii;
+  u8 *p = &pNode->zData[4 + pRtree->nBytesPerCell*iCell];
+  p += writeInt64(p, pCell->iRowid);
+  for(ii=0; ii<(pRtree->nDim*2); ii++){
+    p += writeCoord(p, &pCell->aCoord[ii]);
+  }
+  pNode->isDirty = 1;
 }
 
-static int fulltextBegin(sqlite3_vtab *pVtab){
-  fulltext_vtab *v = (fulltext_vtab *) pVtab;
-  FTSTRACE(("FTS3 xBegin()\n"));
-
-  /* Any buffered updates should have been cleared by the previous
-  ** transaction.
-  */
-  assert( v->nPendingData<0 );
-  return clearPendingTerms(v);
+/*
+** Remove cell the cell with index iCell from node pNode.
+*/
+static void nodeDeleteCell(Rtree *pRtree, RtreeNode *pNode, int iCell){
+  u8 *pDst = &pNode->zData[4 + pRtree->nBytesPerCell*iCell];
+  u8 *pSrc = &pDst[pRtree->nBytesPerCell];
+  int nByte = (NCELL(pNode) - iCell - 1) * pRtree->nBytesPerCell;
+  memmove(pDst, pSrc, nByte);
+  writeInt16(&pNode->zData[2], NCELL(pNode)-1);
+  pNode->isDirty = 1;
 }
 
-static int fulltextCommit(sqlite3_vtab *pVtab){
-  fulltext_vtab *v = (fulltext_vtab *) pVtab;
-  FTSTRACE(("FTS3 xCommit()\n"));
+/*
+** Insert the contents of cell pCell into node pNode. If the insert
+** is successful, return SQLITE_OK.
+**
+** If there is not enough free space in pNode, return SQLITE_FULL.
+*/
+static int
+nodeInsertCell(
+  Rtree *pRtree, 
+  RtreeNode *pNode, 
+  RtreeCell *pCell 
+){
+  int nCell;                    /* Current number of cells in pNode */
+  int nMaxCell;                 /* Maximum number of cells for pNode */
 
-  /* Buffered updates should have been cleared by fulltextSync(). */
-  assert( v->nPendingData<0 );
-  return clearPendingTerms(v);
+  nMaxCell = (pRtree->iNodeSize-4)/pRtree->nBytesPerCell;
+  nCell = NCELL(pNode);
+
+  assert(nCell<=nMaxCell);
+
+  if( nCellzData[2], nCell+1);
+    pNode->isDirty = 1;
+  }
+
+  return (nCell==nMaxCell);
 }
 
-static int fulltextRollback(sqlite3_vtab *pVtab){
-  FTSTRACE(("FTS3 xRollback()\n"));
-  return clearPendingTerms((fulltext_vtab *)pVtab);
+/*
+** If the node is dirty, write it out to the database.
+*/
+static int
+nodeWrite(Rtree *pRtree, RtreeNode *pNode){
+  int rc = SQLITE_OK;
+  if( pNode->isDirty ){
+    sqlite3_stmt *p = pRtree->pWriteNode;
+    if( pNode->iNode ){
+      sqlite3_bind_int64(p, 1, pNode->iNode);
+    }else{
+      sqlite3_bind_null(p, 1);
+    }
+    sqlite3_bind_blob(p, 2, pNode->zData, pRtree->iNodeSize, SQLITE_STATIC);
+    sqlite3_step(p);
+    pNode->isDirty = 0;
+    rc = sqlite3_reset(p);
+    if( pNode->iNode==0 && rc==SQLITE_OK ){
+      pNode->iNode = sqlite3_last_insert_rowid(pRtree->db);
+      nodeHashInsert(pRtree, pNode);
+    }
+  }
+  return rc;
 }
 
 /*
-** Implementation of the snippet() function for FTS3
+** Release a reference to a node. If the node is dirty and the reference
+** count drops to zero, the node data is written to the database.
 */
-static void snippetFunc(
-  sqlite3_context *pContext,
-  int argc,
-  sqlite3_value **argv
-){
-  fulltext_cursor *pCursor;
-  if( argc<1 ) return;
-  if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
-      sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
-    sqlite3_result_error(pContext, "illegal first argument to html_snippet",-1);
-  }else{
-    const char *zStart = "";
-    const char *zEnd = "";
-    const char *zEllipsis = "...";
-    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
-    if( argc>=2 ){
-      zStart = (const char*)sqlite3_value_text(argv[1]);
-      if( argc>=3 ){
-        zEnd = (const char*)sqlite3_value_text(argv[2]);
-        if( argc>=4 ){
-          zEllipsis = (const char*)sqlite3_value_text(argv[3]);
-        }
+static int
+nodeRelease(Rtree *pRtree, RtreeNode *pNode){
+  int rc = SQLITE_OK;
+  if( pNode ){
+    assert( pNode->nRef>0 );
+    pNode->nRef--;
+    if( pNode->nRef==0 ){
+      if( pNode->iNode==1 ){
+        pRtree->iDepth = -1;
+      }
+      if( pNode->pParent ){
+        rc = nodeRelease(pRtree, pNode->pParent);
+      }
+      if( rc==SQLITE_OK ){
+        rc = nodeWrite(pRtree, pNode);
       }
+      nodeHashDelete(pRtree, pNode);
+      sqlite3_free(pNode);
     }
-    snippetAllOffsets(pCursor);
-    snippetText(pCursor, zStart, zEnd, zEllipsis);
-    sqlite3_result_text(pContext, pCursor->snippet.zSnippet,
-                        pCursor->snippet.nSnippet, SQLITE_STATIC);
   }
+  return rc;
 }
 
 /*
-** Implementation of the offsets() function for FTS3
+** Return the 64-bit integer value associated with cell iCell of
+** node pNode. If pNode is a leaf node, this is a rowid. If it is
+** an internal node, then the 64-bit integer is a child page number.
 */
-static void snippetOffsetsFunc(
-  sqlite3_context *pContext,
-  int argc,
-  sqlite3_value **argv
+static i64 nodeGetRowid(
+  Rtree *pRtree, 
+  RtreeNode *pNode, 
+  int iCell
 ){
-  fulltext_cursor *pCursor;
-  if( argc<1 ) return;
-  if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
-      sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
-    sqlite3_result_error(pContext, "illegal first argument to offsets",-1);
-  }else{
-    memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
-    snippetAllOffsets(pCursor);
-    snippetOffsetText(&pCursor->snippet);
-    sqlite3_result_text(pContext,
-                        pCursor->snippet.zOffset, pCursor->snippet.nOffset,
-                        SQLITE_STATIC);
-  }
+  assert( iCellzData[4 + pRtree->nBytesPerCell*iCell]);
 }
 
 /*
-** This routine implements the xFindFunction method for the FTS3
-** virtual table.
+** Return coordinate iCoord from cell iCell in node pNode.
 */
-static int fulltextFindFunction(
-  sqlite3_vtab *pVtab,
-  int nArg,
-  const char *zName,
-  void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
-  void **ppArg
+static void nodeGetCoord(
+  Rtree *pRtree, 
+  RtreeNode *pNode, 
+  int iCell,
+  int iCoord,
+  RtreeCoord *pCoord           /* Space to write result to */
 ){
-  if( strcmp(zName,"snippet")==0 ){
-    *pxFunc = snippetFunc;
-    return 1;
-  }else if( strcmp(zName,"offsets")==0 ){
-    *pxFunc = snippetOffsetsFunc;
-    return 1;
-  }
-  return 0;
+  readCoord(&pNode->zData[12 + pRtree->nBytesPerCell*iCell + 4*iCoord], pCoord);
 }
 
 /*
-** Rename an fts3 table.
+** Deserialize cell iCell of node pNode. Populate the structure pointed
+** to by pCell with the results.
 */
-static int fulltextRename(
-  sqlite3_vtab *pVtab,
-  const char *zName
+static void nodeGetCell(
+  Rtree *pRtree, 
+  RtreeNode *pNode, 
+  int iCell,
+  RtreeCell *pCell
 ){
-  fulltext_vtab *p = (fulltext_vtab *)pVtab;
-  int rc = SQLITE_NOMEM;
-  char *zSql = sqlite3_mprintf(
-    "ALTER TABLE %Q.'%q_content'  RENAME TO '%q_content';"
-    "ALTER TABLE %Q.'%q_segments' RENAME TO '%q_segments';"
-    "ALTER TABLE %Q.'%q_segdir'   RENAME TO '%q_segdir';"
-    , p->zDb, p->zName, zName 
-    , p->zDb, p->zName, zName 
-    , p->zDb, p->zName, zName
-  );
-  if( zSql ){
-    rc = sqlite3_exec(p->db, zSql, 0, 0, 0);
-    sqlite3_free(zSql);
+  int ii;
+  pCell->iRowid = nodeGetRowid(pRtree, pNode, iCell);
+  for(ii=0; iinDim*2; ii++){
+    nodeGetCoord(pRtree, pNode, iCell, ii, &pCell->aCoord[ii]);
   }
-  return rc;
 }
 
-static const sqlite3_module fts3Module = {
-  /* iVersion      */ 0,
-  /* xCreate       */ fulltextCreate,
-  /* xConnect      */ fulltextConnect,
-  /* xBestIndex    */ fulltextBestIndex,
-  /* xDisconnect   */ fulltextDisconnect,
-  /* xDestroy      */ fulltextDestroy,
-  /* xOpen         */ fulltextOpen,
-  /* xClose        */ fulltextClose,
-  /* xFilter       */ fulltextFilter,
-  /* xNext         */ fulltextNext,
-  /* xEof          */ fulltextEof,
-  /* xColumn       */ fulltextColumn,
-  /* xRowid        */ fulltextRowid,
-  /* xUpdate       */ fulltextUpdate,
-  /* xBegin        */ fulltextBegin,
-  /* xSync         */ fulltextSync,
-  /* xCommit       */ fulltextCommit,
-  /* xRollback     */ fulltextRollback,
-  /* xFindFunction */ fulltextFindFunction,
-  /* xRename */       fulltextRename,
-};
 
-static void hashDestroy(void *p){
-  fts3Hash *pHash = (fts3Hash *)p;
-  sqlite3Fts3HashClear(pHash);
-  sqlite3_free(pHash);
+/* Forward declaration for the function that does the work of
+** the virtual table module xCreate() and xConnect() methods.
+*/
+static int rtreeInit(
+  sqlite3 *, void *, int, const char *const*, sqlite3_vtab **, char **, int, int
+);
+
+/* 
+** Rtree virtual table module xCreate method.
+*/
+static int rtreeCreate(
+  sqlite3 *db,
+  void *pAux,
+  int argc, const char *const*argv,
+  sqlite3_vtab **ppVtab,
+  char **pzErr
+){
+  return rtreeInit(db, pAux, argc, argv, ppVtab, pzErr, 1, (int)pAux);
 }
 
-/*
-** The fts3 built-in tokenizers - "simple" and "porter" - are implemented
-** in files fts3_tokenizer1.c and fts3_porter.c respectively. The following
-** two forward declarations are for functions declared in these files
-** used to retrieve the respective implementations.
-**
-** Calling sqlite3Fts3SimpleTokenizerModule() sets the value pointed
-** to by the argument to point a the "simple" tokenizer implementation.
-** Function ...PorterTokenizerModule() sets *pModule to point to the
-** porter tokenizer/stemmer implementation.
+/* 
+** Rtree virtual table module xConnect method.
 */
-SQLITE_PRIVATE void sqlite3Fts3SimpleTokenizerModule(sqlite3_tokenizer_module const**ppModule);
-SQLITE_PRIVATE void sqlite3Fts3PorterTokenizerModule(sqlite3_tokenizer_module const**ppModule);
-SQLITE_PRIVATE void sqlite3Fts3IcuTokenizerModule(sqlite3_tokenizer_module const**ppModule);
+static int rtreeConnect(
+  sqlite3 *db,
+  void *pAux,
+  int argc, const char *const*argv,
+  sqlite3_vtab **ppVtab,
+  char **pzErr
+){
+  return rtreeInit(db, pAux, argc, argv, ppVtab, pzErr, 0, (int)pAux);
+}
 
-SQLITE_PRIVATE int sqlite3Fts3InitHashTable(sqlite3 *, fts3Hash *, const char *);
+/*
+** Increment the r-tree reference count.
+*/
+static void rtreeReference(Rtree *pRtree){
+  pRtree->nBusy++;
+}
 
 /*
-** Initialise the fts3 extension. If this extension is built as part
-** of the sqlite library, then this function is called directly by
-** SQLite. If fts3 is built as a dynamically loadable extension, this
-** function is called by the sqlite3_extension_init() entry point.
+** Decrement the r-tree reference count. When the reference count reaches
+** zero the structure is deleted.
 */
-SQLITE_PRIVATE int sqlite3Fts3Init(sqlite3 *db){
-  int rc = SQLITE_OK;
-  fts3Hash *pHash = 0;
-  const sqlite3_tokenizer_module *pSimple = 0;
-  const sqlite3_tokenizer_module *pPorter = 0;
-  const sqlite3_tokenizer_module *pIcu = 0;
+static void rtreeRelease(Rtree *pRtree){
+  pRtree->nBusy--;
+  if( pRtree->nBusy==0 ){
+    sqlite3_finalize(pRtree->pReadNode);
+    sqlite3_finalize(pRtree->pWriteNode);
+    sqlite3_finalize(pRtree->pDeleteNode);
+    sqlite3_finalize(pRtree->pReadRowid);
+    sqlite3_finalize(pRtree->pWriteRowid);
+    sqlite3_finalize(pRtree->pDeleteRowid);
+    sqlite3_finalize(pRtree->pReadParent);
+    sqlite3_finalize(pRtree->pWriteParent);
+    sqlite3_finalize(pRtree->pDeleteParent);
+    sqlite3_free(pRtree);
+  }
+}
 
-  sqlite3Fts3SimpleTokenizerModule(&pSimple);
-  sqlite3Fts3PorterTokenizerModule(&pPorter);
-#ifdef SQLITE_ENABLE_ICU
-  sqlite3Fts3IcuTokenizerModule(&pIcu);
-#endif
+/* 
+** Rtree virtual table module xDisconnect method.
+*/
+static int rtreeDisconnect(sqlite3_vtab *pVtab){
+  rtreeRelease((Rtree *)pVtab);
+  return SQLITE_OK;
+}
 
-  /* Allocate and initialise the hash-table used to store tokenizers. */
-  pHash = sqlite3_malloc(sizeof(fts3Hash));
-  if( !pHash ){
+/* 
+** Rtree virtual table module xDestroy method.
+*/
+static int rtreeDestroy(sqlite3_vtab *pVtab){
+  Rtree *pRtree = (Rtree *)pVtab;
+  int rc;
+  char *zCreate = sqlite3_mprintf(
+    "DROP TABLE '%q'.'%q_node';"
+    "DROP TABLE '%q'.'%q_rowid';"
+    "DROP TABLE '%q'.'%q_parent';",
+    pRtree->zDb, pRtree->zName, 
+    pRtree->zDb, pRtree->zName,
+    pRtree->zDb, pRtree->zName
+  );
+  if( !zCreate ){
     rc = SQLITE_NOMEM;
   }else{
-    sqlite3Fts3HashInit(pHash, FTS3_HASH_STRING, 1);
+    rc = sqlite3_exec(pRtree->db, zCreate, 0, 0, 0);
+    sqlite3_free(zCreate);
   }
-
-  /* Load the built-in tokenizers into the hash table */
   if( rc==SQLITE_OK ){
-    if( sqlite3Fts3HashInsert(pHash, "simple", 7, (void *)pSimple)
-     || sqlite3Fts3HashInsert(pHash, "porter", 7, (void *)pPorter) 
-     || (pIcu && sqlite3Fts3HashInsert(pHash, "icu", 4, (void *)pIcu))
-    ){
-      rc = SQLITE_NOMEM;
-    }
+    rtreeRelease(pRtree);
   }
 
-  /* Create the virtual table wrapper around the hash-table and overload 
-  ** the two scalar functions. If this is successful, register the
-  ** module with sqlite.
-  */
-  if( SQLITE_OK==rc 
-   && SQLITE_OK==(rc = sqlite3Fts3InitHashTable(db, pHash, "fts3_tokenizer"))
-   && SQLITE_OK==(rc = sqlite3_overload_function(db, "snippet", -1))
-   && SQLITE_OK==(rc = sqlite3_overload_function(db, "offsets", -1))
-  ){
-    return sqlite3_create_module_v2(
-        db, "fts3", &fts3Module, (void *)pHash, hashDestroy
-    );
-  }
+  return rc;
+}
 
-  /* An error has occured. Delete the hash table and return the error code. */
-  assert( rc!=SQLITE_OK );
-  if( pHash ){
-    sqlite3Fts3HashClear(pHash);
-    sqlite3_free(pHash);
+/* 
+** Rtree virtual table module xOpen method.
+*/
+static int rtreeOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
+  int rc = SQLITE_NOMEM;
+  RtreeCursor *pCsr;
+
+  pCsr = (RtreeCursor *)sqlite3_malloc(sizeof(RtreeCursor));
+  if( pCsr ){
+    memset(pCsr, 0, sizeof(RtreeCursor));
+    pCsr->base.pVtab = pVTab;
+    rc = SQLITE_OK;
   }
+  *ppCursor = (sqlite3_vtab_cursor *)pCsr;
+
   return rc;
 }
 
-#if !SQLITE_CORE
-SQLITE_API int sqlite3_extension_init(
-  sqlite3 *db, 
-  char **pzErrMsg,
-  const sqlite3_api_routines *pApi
-){
-  SQLITE_EXTENSION_INIT2(pApi)
-  return sqlite3Fts3Init(db);
+/* 
+** Rtree virtual table module xClose method.
+*/
+static int rtreeClose(sqlite3_vtab_cursor *cur){
+  Rtree *pRtree = (Rtree *)(cur->pVtab);
+  int rc;
+  RtreeCursor *pCsr = (RtreeCursor *)cur;
+  sqlite3_free(pCsr->aConstraint);
+  rc = nodeRelease(pRtree, pCsr->pNode);
+  sqlite3_free(pCsr);
+  return rc;
 }
-#endif
-
-#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
 
-/************** End of fts3.c ************************************************/
-/************** Begin file fts3_hash.c ***************************************/
 /*
-** 2001 September 22
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
+** Rtree virtual table module xEof method.
 **
-*************************************************************************
-** This is the implementation of generic hash-tables used in SQLite.
-** We've modified it slightly to serve as a standalone hash table
-** implementation for the full-text indexing module.
+** Return non-zero if the cursor does not currently point to a valid 
+** record (i.e if the scan has finished), or zero otherwise.
 */
+static int rtreeEof(sqlite3_vtab_cursor *cur){
+  RtreeCursor *pCsr = (RtreeCursor *)cur;
+  return (pCsr->pNode==0);
+}
 
-/*
-** The code in this file is only compiled if:
-**
-**     * The FTS3 module is being built as an extension
-**       (in which case SQLITE_CORE is not defined), or
-**
-**     * The FTS3 module is being built into the core of
-**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
+/* 
+** Cursor pCursor currently points to a cell in a non-leaf page.
+** Return true if the sub-tree headed by the cell is filtered
+** (excluded) by the constraints in the pCursor->aConstraint[] 
+** array, or false otherwise.
 */
-#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
+static int testRtreeCell(Rtree *pRtree, RtreeCursor *pCursor){
+  RtreeCell cell;
+  int ii;
+  int bRes = 0;
 
+  nodeGetCell(pRtree, pCursor->pNode, pCursor->iCell, &cell);
+  for(ii=0; bRes==0 && iinConstraint; ii++){
+    RtreeConstraint *p = &pCursor->aConstraint[ii];
+    double cell_min = DCOORD(cell.aCoord[(p->iCoord>>1)*2]);
+    double cell_max = DCOORD(cell.aCoord[(p->iCoord>>1)*2+1]);
 
+    assert(p->op==RTREE_LE || p->op==RTREE_LT || p->op==RTREE_GE 
+        || p->op==RTREE_GT || p->op==RTREE_EQ
+    );
 
-/*
-** Malloc and Free functions
-*/
-static void *fts3HashMalloc(int n){
-  void *p = sqlite3_malloc(n);
-  if( p ){
-    memset(p, 0, n);
+    switch( p->op ){
+      case RTREE_LE: case RTREE_LT: bRes = p->rValuerValue>cell_max; break;
+      case RTREE_EQ: 
+        bRes = (p->rValue>cell_max || p->rValueaConstraint[] array, or false otherwise.
 **
-** "pNew" is a pointer to the hash table that is to be initialized.
-** keyClass is one of the constants 
-** FTS3_HASH_BINARY or FTS3_HASH_STRING.  The value of keyClass 
-** determines what kind of key the hash table will use.  "copyKey" is
-** true if the hash table should make its own private copy of keys and
-** false if it should just use the supplied pointer.
+** This function assumes that the cell is part of a leaf node.
 */
-SQLITE_PRIVATE void sqlite3Fts3HashInit(fts3Hash *pNew, int keyClass, int copyKey){
-  assert( pNew!=0 );
-  assert( keyClass>=FTS3_HASH_STRING && keyClass<=FTS3_HASH_BINARY );
-  pNew->keyClass = keyClass;
-  pNew->copyKey = copyKey;
-  pNew->first = 0;
-  pNew->count = 0;
-  pNew->htsize = 0;
-  pNew->ht = 0;
+static int testRtreeEntry(Rtree *pRtree, RtreeCursor *pCursor){
+  RtreeCell cell;
+  int ii;
+
+  nodeGetCell(pRtree, pCursor->pNode, pCursor->iCell, &cell);
+  for(ii=0; iinConstraint; ii++){
+    RtreeConstraint *p = &pCursor->aConstraint[ii];
+    double coord = DCOORD(cell.aCoord[p->iCoord]);
+    int res;
+    assert(p->op==RTREE_LE || p->op==RTREE_LT || p->op==RTREE_GE 
+        || p->op==RTREE_GT || p->op==RTREE_EQ
+    );
+    switch( p->op ){
+      case RTREE_LE: res = (coord<=p->rValue); break;
+      case RTREE_LT: res = (coordrValue);  break;
+      case RTREE_GE: res = (coord>=p->rValue); break;
+      case RTREE_GT: res = (coord>p->rValue);  break;
+      case RTREE_EQ: res = (coord==p->rValue); break;
+    }
+
+    if( !res ) return 1;
+  }
+
+  return 0;
 }
 
-/* Remove all entries from a hash table.  Reclaim all memory.
-** Call this routine to delete a hash table or to reset a hash table
-** to the empty state.
+/*
+** Cursor pCursor currently points at a node that heads a sub-tree of
+** height iHeight (if iHeight==0, then the node is a leaf). Descend
+** to point to the left-most cell of the sub-tree that matches the 
+** configured constraints.
 */
-SQLITE_PRIVATE void sqlite3Fts3HashClear(fts3Hash *pH){
-  fts3HashElem *elem;         /* For looping over all elements of the table */
+static int descendToCell(
+  Rtree *pRtree, 
+  RtreeCursor *pCursor, 
+  int iHeight,
+  int *pEof                 /* OUT: Set to true if cannot descend */
+){
+  int isEof;
+  int rc;
+  int ii;
+  RtreeNode *pChild;
+  sqlite3_int64 iRowid;
 
-  assert( pH!=0 );
-  elem = pH->first;
-  pH->first = 0;
-  fts3HashFree(pH->ht);
-  pH->ht = 0;
-  pH->htsize = 0;
-  while( elem ){
-    fts3HashElem *next_elem = elem->next;
-    if( pH->copyKey && elem->pKey ){
-      fts3HashFree(elem->pKey);
+  RtreeNode *pSavedNode = pCursor->pNode;
+  int iSavedCell = pCursor->iCell;
+
+  assert( iHeight>=0 );
+
+  if( iHeight==0 ){
+    isEof = testRtreeEntry(pRtree, pCursor);
+  }else{
+    isEof = testRtreeCell(pRtree, pCursor);
+  }
+  if( isEof || iHeight==0 ){
+    *pEof = isEof;
+    return SQLITE_OK;
+  }
+
+  iRowid = nodeGetRowid(pRtree, pCursor->pNode, pCursor->iCell);
+  rc = nodeAcquire(pRtree, iRowid, pCursor->pNode, &pChild);
+  if( rc!=SQLITE_OK ){
+    return rc;
+  }
+
+  nodeRelease(pRtree, pCursor->pNode);
+  pCursor->pNode = pChild;
+  isEof = 1;
+  for(ii=0; isEof && iiiCell = ii;
+    rc = descendToCell(pRtree, pCursor, iHeight-1, &isEof);
+    if( rc!=SQLITE_OK ){
+      return rc;
     }
-    fts3HashFree(elem);
-    elem = next_elem;
   }
-  pH->count = 0;
+
+  if( isEof ){
+    assert( pCursor->pNode==pChild );
+    nodeReference(pSavedNode);
+    nodeRelease(pRtree, pChild);
+    pCursor->pNode = pSavedNode;
+    pCursor->iCell = iSavedCell;
+  }
+
+  *pEof = isEof;
+  return SQLITE_OK;
 }
 
 /*
-** Hash and comparison functions when the mode is FTS3_HASH_STRING
+** One of the cells in node pNode is guaranteed to have a 64-bit 
+** integer value equal to iRowid. Return the index of this cell.
 */
-static int fts3StrHash(const void *pKey, int nKey){
-  const char *z = (const char *)pKey;
-  int h = 0;
-  if( nKey<=0 ) nKey = (int) strlen(z);
-  while( nKey > 0  ){
-    h = (h<<3) ^ h ^ *z++;
-    nKey--;
+static int nodeRowidIndex(Rtree *pRtree, RtreeNode *pNode, i64 iRowid){
+  int ii;
+  for(ii=0; nodeGetRowid(pRtree, pNode, ii)!=iRowid; ii++){
+    assert( ii<(NCELL(pNode)-1) );
   }
-  return h & 0x7fffffff;
-}
-static int fts3StrCompare(const void *pKey1, int n1, const void *pKey2, int n2){
-  if( n1!=n2 ) return 1;
-  return strncmp((const char*)pKey1,(const char*)pKey2,n1);
+  return ii;
 }
 
 /*
-** Hash and comparison functions when the mode is FTS3_HASH_BINARY
+** Return the index of the cell containing a pointer to node pNode
+** in its parent. If pNode is the root node, return -1.
 */
-static int fts3BinHash(const void *pKey, int nKey){
-  int h = 0;
-  const char *z = (const char *)pKey;
-  while( nKey-- > 0 ){
-    h = (h<<3) ^ h ^ *(z++);
+static int nodeParentIndex(Rtree *pRtree, RtreeNode *pNode){
+  RtreeNode *pParent = pNode->pParent;
+  if( pParent ){
+    return nodeRowidIndex(pRtree, pParent, pNode->iNode);
   }
-  return h & 0x7fffffff;
-}
-static int fts3BinCompare(const void *pKey1, int n1, const void *pKey2, int n2){
-  if( n1!=n2 ) return 1;
-  return memcmp(pKey1,pKey2,n1);
+  return -1;
 }
 
-/*
-** Return a pointer to the appropriate hash function given the key class.
-**
-** The C syntax in this function definition may be unfamilar to some 
-** programmers, so we provide the following additional explanation:
-**
-** The name of the function is "ftsHashFunction".  The function takes a
-** single parameter "keyClass".  The return value of ftsHashFunction()
-** is a pointer to another function.  Specifically, the return value
-** of ftsHashFunction() is a pointer to a function that takes two parameters
-** with types "const void*" and "int" and returns an "int".
+/* 
+** Rtree virtual table module xNext method.
 */
-static int (*ftsHashFunction(int keyClass))(const void*,int){
-  if( keyClass==FTS3_HASH_STRING ){
-    return &fts3StrHash;
-  }else{
-    assert( keyClass==FTS3_HASH_BINARY );
-    return &fts3BinHash;
+static int rtreeNext(sqlite3_vtab_cursor *pVtabCursor){
+  Rtree *pRtree = (Rtree *)(pVtabCursor->pVtab);
+  RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
+  int rc = SQLITE_OK;
+
+  if( pCsr->iStrategy==1 ){
+    /* This "scan" is a direct lookup by rowid. There is no next entry. */
+    nodeRelease(pRtree, pCsr->pNode);
+    pCsr->pNode = 0;
+  }
+
+  else if( pCsr->pNode ){
+    /* Move to the next entry that matches the configured constraints. */
+    int iHeight = 0;
+    while( pCsr->pNode ){
+      RtreeNode *pNode = pCsr->pNode;
+      int nCell = NCELL(pNode);
+      for(pCsr->iCell++; pCsr->iCelliCell++){
+        int isEof;
+        rc = descendToCell(pRtree, pCsr, iHeight, &isEof);
+        if( rc!=SQLITE_OK || !isEof ){
+          return rc;
+        }
+      }
+      pCsr->pNode = pNode->pParent;
+      pCsr->iCell = nodeParentIndex(pRtree, pNode);
+      nodeReference(pCsr->pNode);
+      nodeRelease(pRtree, pNode);
+      iHeight++;
+    }
   }
+
+  return rc;
 }
 
-/*
-** Return a pointer to the appropriate hash function given the key class.
-**
-** For help in interpreted the obscure C code in the function definition,
-** see the header comment on the previous function.
+/* 
+** Rtree virtual table module xRowid method.
 */
-static int (*ftsCompareFunction(int keyClass))(const void*,int,const void*,int){
-  if( keyClass==FTS3_HASH_STRING ){
-    return &fts3StrCompare;
+static int rtreeRowid(sqlite3_vtab_cursor *pVtabCursor, sqlite_int64 *pRowid){
+  Rtree *pRtree = (Rtree *)pVtabCursor->pVtab;
+  RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
+
+  assert(pCsr->pNode);
+  *pRowid = nodeGetRowid(pRtree, pCsr->pNode, pCsr->iCell);
+
+  return SQLITE_OK;
+}
+
+/* 
+** Rtree virtual table module xColumn method.
+*/
+static int rtreeColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
+  Rtree *pRtree = (Rtree *)cur->pVtab;
+  RtreeCursor *pCsr = (RtreeCursor *)cur;
+
+  if( i==0 ){
+    i64 iRowid = nodeGetRowid(pRtree, pCsr->pNode, pCsr->iCell);
+    sqlite3_result_int64(ctx, iRowid);
   }else{
-    assert( keyClass==FTS3_HASH_BINARY );
-    return &fts3BinCompare;
+    RtreeCoord c;
+    nodeGetCoord(pRtree, pCsr->pNode, pCsr->iCell, i-1, &c);
+    if( pRtree->eCoordType==RTREE_COORD_REAL32 ){
+      sqlite3_result_double(ctx, c.f);
+    }else{
+      assert( pRtree->eCoordType==RTREE_COORD_INT32 );
+      sqlite3_result_int(ctx, c.i);
+    }
   }
+
+  return SQLITE_OK;
 }
 
-/* Link an element into the hash table
+/* 
+** Use nodeAcquire() to obtain the leaf node containing the record with 
+** rowid iRowid. If successful, set *ppLeaf to point to the node and
+** return SQLITE_OK. If there is no such record in the table, set
+** *ppLeaf to 0 and return SQLITE_OK. If an error occurs, set *ppLeaf
+** to zero and return an SQLite error code.
 */
-static void fts3HashInsertElement(
-  fts3Hash *pH,            /* The complete hash table */
-  struct _fts3ht *pEntry,  /* The entry into which pNew is inserted */
-  fts3HashElem *pNew       /* The element to be inserted */
-){
-  fts3HashElem *pHead;     /* First element already in pEntry */
-  pHead = pEntry->chain;
-  if( pHead ){
-    pNew->next = pHead;
-    pNew->prev = pHead->prev;
-    if( pHead->prev ){ pHead->prev->next = pNew; }
-    else             { pH->first = pNew; }
-    pHead->prev = pNew;
+static int findLeafNode(Rtree *pRtree, i64 iRowid, RtreeNode **ppLeaf){
+  int rc;
+  *ppLeaf = 0;
+  sqlite3_bind_int64(pRtree->pReadRowid, 1, iRowid);
+  if( sqlite3_step(pRtree->pReadRowid)==SQLITE_ROW ){
+    i64 iNode = sqlite3_column_int64(pRtree->pReadRowid, 0);
+    rc = nodeAcquire(pRtree, iNode, 0, ppLeaf);
+    sqlite3_reset(pRtree->pReadRowid);
   }else{
-    pNew->next = pH->first;
-    if( pH->first ){ pH->first->prev = pNew; }
-    pNew->prev = 0;
-    pH->first = pNew;
+    rc = sqlite3_reset(pRtree->pReadRowid);
   }
-  pEntry->count++;
-  pEntry->chain = pNew;
+  return rc;
 }
 
 
-/* Resize the hash table so that it cantains "new_size" buckets.
-** "new_size" must be a power of 2.  The hash table might fail 
-** to resize if sqliteMalloc() fails.
+/* 
+** Rtree virtual table module xFilter method.
 */
-static void fts3Rehash(fts3Hash *pH, int new_size){
-  struct _fts3ht *new_ht;          /* The new hash table */
-  fts3HashElem *elem, *next_elem;  /* For looping over existing elements */
-  int (*xHash)(const void*,int);   /* The hash function */
+static int rtreeFilter(
+  sqlite3_vtab_cursor *pVtabCursor, 
+  int idxNum, const char *idxStr,
+  int argc, sqlite3_value **argv
+){
+  Rtree *pRtree = (Rtree *)pVtabCursor->pVtab;
+  RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
 
-  assert( (new_size & (new_size-1))==0 );
-  new_ht = (struct _fts3ht *)fts3HashMalloc( new_size*sizeof(struct _fts3ht) );
-  if( new_ht==0 ) return;
-  fts3HashFree(pH->ht);
-  pH->ht = new_ht;
-  pH->htsize = new_size;
-  xHash = ftsHashFunction(pH->keyClass);
-  for(elem=pH->first, pH->first=0; elem; elem = next_elem){
-    int h = (*xHash)(elem->pKey, elem->nKey) & (new_size-1);
-    next_elem = elem->next;
-    fts3HashInsertElement(pH, &new_ht[h], elem);
+  RtreeNode *pRoot = 0;
+  int ii;
+  int rc = SQLITE_OK;
+
+  rtreeReference(pRtree);
+
+  sqlite3_free(pCsr->aConstraint);
+  pCsr->aConstraint = 0;
+  pCsr->iStrategy = idxNum;
+
+  if( idxNum==1 ){
+    /* Special case - lookup by rowid. */
+    RtreeNode *pLeaf;        /* Leaf on which the required cell resides */
+    i64 iRowid = sqlite3_value_int64(argv[0]);
+    rc = findLeafNode(pRtree, iRowid, &pLeaf);
+    pCsr->pNode = pLeaf; 
+    if( pLeaf && rc==SQLITE_OK ){
+      pCsr->iCell = nodeRowidIndex(pRtree, pLeaf, iRowid);
+    }
+  }else{
+    /* Normal case - r-tree scan. Set up the RtreeCursor.aConstraint array 
+    ** with the configured constraints. 
+    */
+    if( argc>0 ){
+      pCsr->aConstraint = sqlite3_malloc(sizeof(RtreeConstraint)*argc);
+      pCsr->nConstraint = argc;
+      if( !pCsr->aConstraint ){
+        rc = SQLITE_NOMEM;
+      }else{
+        assert( (idxStr==0 && argc==0) || strlen(idxStr)==argc*2 );
+        for(ii=0; iiaConstraint[ii];
+          p->op = idxStr[ii*2];
+          p->iCoord = idxStr[ii*2+1]-'a';
+          p->rValue = sqlite3_value_double(argv[ii]);
+        }
+      }
+    }
+  
+    if( rc==SQLITE_OK ){
+      pCsr->pNode = 0;
+      rc = nodeAcquire(pRtree, 1, 0, &pRoot);
+    }
+    if( rc==SQLITE_OK ){
+      int isEof = 1;
+      int nCell = NCELL(pRoot);
+      pCsr->pNode = pRoot;
+      for(pCsr->iCell=0; rc==SQLITE_OK && pCsr->iCelliCell++){
+        assert( pCsr->pNode==pRoot );
+        rc = descendToCell(pRtree, pCsr, pRtree->iDepth, &isEof);
+        if( !isEof ){
+          break;
+        }
+      }
+      if( rc==SQLITE_OK && isEof ){
+        assert( pCsr->pNode==pRoot );
+        nodeRelease(pRtree, pRoot);
+        pCsr->pNode = 0;
+      }
+      assert( rc!=SQLITE_OK || !pCsr->pNode || pCsr->iCellpNode) );
+    }
   }
+
+  rtreeRelease(pRtree);
+  return rc;
 }
 
-/* This function (for internal use only) locates an element in an
-** hash table that matches the given key.  The hash for this key has
-** already been computed and is passed as the 4th parameter.
+/*
+** Rtree virtual table module xBestIndex method. There are three
+** table scan strategies to choose from (in order from most to 
+** least desirable):
+**
+**   idxNum     idxStr        Strategy
+**   ------------------------------------------------
+**     1        Unused        Direct lookup by rowid.
+**     2        See below     R-tree query.
+**     3        Unused        Full table scan.
+**   ------------------------------------------------
+**
+** If strategy 1 or 3 is used, then idxStr is not meaningful. If strategy
+** 2 is used, idxStr is formatted to contain 2 bytes for each 
+** constraint used. The first two bytes of idxStr correspond to 
+** the constraint in sqlite3_index_info.aConstraintUsage[] with
+** (argvIndex==1) etc.
+**
+** The first of each pair of bytes in idxStr identifies the constraint
+** operator as follows:
+**
+**   Operator    Byte Value
+**   ----------------------
+**      =        0x41 ('A')
+**     <=        0x42 ('B')
+**      <        0x43 ('C')
+**     >=        0x44 ('D')
+**      >        0x45 ('E')
+**   ----------------------
+**
+** The second of each pair of bytes identifies the coordinate column
+** to which the constraint applies. The leftmost coordinate column
+** is 'a', the second from the left 'b' etc.
 */
-static fts3HashElem *fts3FindElementByHash(
-  const fts3Hash *pH, /* The pH to be searched */
-  const void *pKey,   /* The key we are searching for */
-  int nKey,
-  int h               /* The hash for this key. */
-){
-  fts3HashElem *elem;            /* Used to loop thru the element list */
-  int count;                     /* Number of elements left to test */
-  int (*xCompare)(const void*,int,const void*,int);  /* comparison function */
+static int rtreeBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
+  int rc = SQLITE_OK;
+  int ii, cCol;
 
-  if( pH->ht ){
-    struct _fts3ht *pEntry = &pH->ht[h];
-    elem = pEntry->chain;
-    count = pEntry->count;
-    xCompare = ftsCompareFunction(pH->keyClass);
-    while( count-- && elem ){
-      if( (*xCompare)(elem->pKey,elem->nKey,pKey,nKey)==0 ){ 
-        return elem;
+  int iIdx = 0;
+  char zIdxStr[RTREE_MAX_DIMENSIONS*8+1];
+  memset(zIdxStr, 0, sizeof(zIdxStr));
+
+  assert( pIdxInfo->idxStr==0 );
+  for(ii=0; iinConstraint; ii++){
+    struct sqlite3_index_constraint *p = &pIdxInfo->aConstraint[ii];
+
+    if( p->usable && p->iColumn==0 && p->op==SQLITE_INDEX_CONSTRAINT_EQ ){
+      /* We have an equality constraint on the rowid. Use strategy 1. */
+      int jj;
+      for(jj=0; jjaConstraintUsage[jj].argvIndex = 0;
+        pIdxInfo->aConstraintUsage[jj].omit = 0;
+      }
+      pIdxInfo->idxNum = 1;
+      pIdxInfo->aConstraintUsage[ii].argvIndex = 1;
+      pIdxInfo->aConstraintUsage[jj].omit = 1;
+
+      /* This strategy involves a two rowid lookups on an B-Tree structures
+      ** and then a linear search of an R-Tree node. This should be 
+      ** considered almost as quick as a direct rowid lookup (for which 
+      ** sqlite uses an internal cost of 0.0).
+      */ 
+      pIdxInfo->estimatedCost = 10.0;
+      return SQLITE_OK;
+    }
+
+    if( p->usable && p->iColumn>0 ){
+      u8 op = 0;
+      switch( p->op ){
+        case SQLITE_INDEX_CONSTRAINT_EQ: op = RTREE_EQ; break;
+        case SQLITE_INDEX_CONSTRAINT_GT: op = RTREE_GT; break;
+        case SQLITE_INDEX_CONSTRAINT_LE: op = RTREE_LE; break;
+        case SQLITE_INDEX_CONSTRAINT_LT: op = RTREE_LT; break;
+        case SQLITE_INDEX_CONSTRAINT_GE: op = RTREE_GE; break;
+      }
+      if( op ){
+        /* Make sure this particular constraint has not been used before.
+        ** If it has been used before, ignore it.
+        **
+        ** A <= or < can be used if there is a prior >= or >.
+        ** A >= or > can be used if there is a prior < or <=.
+        ** A <= or < is disqualified if there is a prior <=, <, or ==.
+        ** A >= or > is disqualified if there is a prior >=, >, or ==.
+        ** A == is disqualifed if there is any prior constraint.
+        */
+        int j, opmsk;
+        static const unsigned char compatible[] = { 0, 0, 1, 1, 2, 2 };
+        assert( compatible[RTREE_EQ & 7]==0 );
+        assert( compatible[RTREE_LT & 7]==1 );
+        assert( compatible[RTREE_LE & 7]==1 );
+        assert( compatible[RTREE_GT & 7]==2 );
+        assert( compatible[RTREE_GE & 7]==2 );
+        cCol = p->iColumn - 1 + 'a';
+        opmsk = compatible[op & 7];
+        for(j=0; jaConstraintUsage[ii].argvIndex = (iIdx/2);
+        pIdxInfo->aConstraintUsage[ii].omit = 1;
       }
-      elem = elem->next;
     }
   }
-  return 0;
+
+  pIdxInfo->idxNum = 2;
+  pIdxInfo->needToFreeIdxStr = 1;
+  if( iIdx>0 && 0==(pIdxInfo->idxStr = sqlite3_mprintf("%s", zIdxStr)) ){
+    return SQLITE_NOMEM;
+  }
+  assert( iIdx>=0 );
+  pIdxInfo->estimatedCost = (2000000.0 / (double)(iIdx + 1));
+  return rc;
 }
 
-/* Remove a single entry from the hash table given a pointer to that
-** element and a hash on the element's key.
+/*
+** Return the N-dimensional volumn of the cell stored in *p.
 */
-static void fts3RemoveElementByHash(
-  fts3Hash *pH,         /* The pH containing "elem" */
-  fts3HashElem* elem,   /* The element to be removed from the pH */
-  int h                 /* Hash value for the element */
-){
-  struct _fts3ht *pEntry;
-  if( elem->prev ){
-    elem->prev->next = elem->next; 
-  }else{
-    pH->first = elem->next;
-  }
-  if( elem->next ){
-    elem->next->prev = elem->prev;
-  }
-  pEntry = &pH->ht[h];
-  if( pEntry->chain==elem ){
-    pEntry->chain = elem->next;
+static float cellArea(Rtree *pRtree, RtreeCell *p){
+  float area = 1.0;
+  int ii;
+  for(ii=0; ii<(pRtree->nDim*2); ii+=2){
+    area = area * (DCOORD(p->aCoord[ii+1]) - DCOORD(p->aCoord[ii]));
   }
-  pEntry->count--;
-  if( pEntry->count<=0 ){
-    pEntry->chain = 0;
+  return area;
+}
+
+/*
+** Return the margin length of cell p. The margin length is the sum
+** of the objects size in each dimension.
+*/
+static float cellMargin(Rtree *pRtree, RtreeCell *p){
+  float margin = 0.0;
+  int ii;
+  for(ii=0; ii<(pRtree->nDim*2); ii+=2){
+    margin += (DCOORD(p->aCoord[ii+1]) - DCOORD(p->aCoord[ii]));
   }
-  if( pH->copyKey && elem->pKey ){
-    fts3HashFree(elem->pKey);
+  return margin;
+}
+
+/*
+** Store the union of cells p1 and p2 in p1.
+*/
+static void cellUnion(Rtree *pRtree, RtreeCell *p1, RtreeCell *p2){
+  int ii;
+  if( pRtree->eCoordType==RTREE_COORD_REAL32 ){
+    for(ii=0; ii<(pRtree->nDim*2); ii+=2){
+      p1->aCoord[ii].f = MIN(p1->aCoord[ii].f, p2->aCoord[ii].f);
+      p1->aCoord[ii+1].f = MAX(p1->aCoord[ii+1].f, p2->aCoord[ii+1].f);
+    }
+  }else{
+    for(ii=0; ii<(pRtree->nDim*2); ii+=2){
+      p1->aCoord[ii].i = MIN(p1->aCoord[ii].i, p2->aCoord[ii].i);
+      p1->aCoord[ii+1].i = MAX(p1->aCoord[ii+1].i, p2->aCoord[ii+1].i);
+    }
   }
-  fts3HashFree( elem );
-  pH->count--;
-  if( pH->count<=0 ){
-    assert( pH->first==0 );
-    assert( pH->count==0 );
-    fts3HashClear(pH);
+}
+
+/*
+** Return true if the area covered by p2 is a subset of the area covered
+** by p1. False otherwise.
+*/
+static int cellContains(Rtree *pRtree, RtreeCell *p1, RtreeCell *p2){
+  int ii;
+  int isInt = (pRtree->eCoordType==RTREE_COORD_INT32);
+  for(ii=0; ii<(pRtree->nDim*2); ii+=2){
+    RtreeCoord *a1 = &p1->aCoord[ii];
+    RtreeCoord *a2 = &p2->aCoord[ii];
+    if( (!isInt && (a2[0].fa1[1].f)) 
+     || ( isInt && (a2[0].ia1[1].i)) 
+    ){
+      return 0;
+    }
   }
+  return 1;
 }
 
-/* Attempt to locate an element of the hash table pH with a key
-** that matches pKey,nKey.  Return the data for this element if it is
-** found, or NULL if there is no match.
+/*
+** Return the amount cell p would grow by if it were unioned with pCell.
 */
-SQLITE_PRIVATE void *sqlite3Fts3HashFind(const fts3Hash *pH, const void *pKey, int nKey){
-  int h;                 /* A hash on key */
-  fts3HashElem *elem;    /* The element that matches key */
-  int (*xHash)(const void*,int);  /* The hash function */
+static float cellGrowth(Rtree *pRtree, RtreeCell *p, RtreeCell *pCell){
+  float area;
+  RtreeCell cell;
+  memcpy(&cell, p, sizeof(RtreeCell));
+  area = cellArea(pRtree, &cell);
+  cellUnion(pRtree, &cell, pCell);
+  return (cellArea(pRtree, &cell)-area);
+}
 
-  if( pH==0 || pH->ht==0 ) return 0;
-  xHash = ftsHashFunction(pH->keyClass);
-  assert( xHash!=0 );
-  h = (*xHash)(pKey,nKey);
-  assert( (pH->htsize & (pH->htsize-1))==0 );
-  elem = fts3FindElementByHash(pH,pKey,nKey, h & (pH->htsize-1));
-  return elem ? elem->data : 0;
+#if VARIANT_RSTARTREE_CHOOSESUBTREE || VARIANT_RSTARTREE_SPLIT
+static float cellOverlap(
+  Rtree *pRtree, 
+  RtreeCell *p, 
+  RtreeCell *aCell, 
+  int nCell, 
+  int iExclude
+){
+  int ii;
+  float overlap = 0.0;
+  for(ii=0; iinDim*2); jj+=2){
+        double x1;
+        double x2;
+
+        x1 = MAX(DCOORD(p->aCoord[jj]), DCOORD(aCell[ii].aCoord[jj]));
+        x2 = MIN(DCOORD(p->aCoord[jj+1]), DCOORD(aCell[ii].aCoord[jj+1]));
+
+        if( x2keyClass);
-  assert( xHash!=0 );
-  hraw = (*xHash)(pKey, nKey);
-  assert( (pH->htsize & (pH->htsize-1))==0 );
-  h = hraw & (pH->htsize-1);
-  elem = fts3FindElementByHash(pH,pKey,nKey,h);
-  if( elem ){
-    void *old_data = elem->data;
-    if( data==0 ){
-      fts3RemoveElementByHash(pH,elem,h);
-    }else{
-      elem->data = data;
+  for(ii=0; rc==SQLITE_OK && ii<(pRtree->iDepth-iHeight); ii++){
+    int iCell;
+    sqlite3_int64 iBest;
+
+    float fMinGrowth;
+    float fMinArea;
+    float fMinOverlap;
+
+    int nCell = NCELL(pNode);
+    RtreeCell cell;
+    RtreeNode *pChild;
+
+    RtreeCell *aCell = 0;
+
+#if VARIANT_RSTARTREE_CHOOSESUBTREE
+    if( ii==(pRtree->iDepth-1) ){
+      int jj;
+      aCell = sqlite3_malloc(sizeof(RtreeCell)*nCell);
+      if( !aCell ){
+        rc = SQLITE_NOMEM;
+        nodeRelease(pRtree, pNode);
+        pNode = 0;
+        continue;
+      }
+      for(jj=0; jjcopyKey && pKey!=0 ){
-    new_elem->pKey = fts3HashMalloc( nKey );
-    if( new_elem->pKey==0 ){
-      fts3HashFree(new_elem);
-      return data;
+#endif
+
+    /* Select the child node which will be enlarged the least if pCell
+    ** is inserted into it. Resolve ties by choosing the entry with
+    ** the smallest area.
+    */
+    for(iCell=0; iCelliDepth-1) ){
+        overlap = cellOverlapEnlargement(pRtree,&cell,pCell,aCell,nCell,iCell);
+      }
+#endif
+      if( (iCell==0) 
+       || (overlappKey, pKey, nKey);
-  }else{
-    new_elem->pKey = (void*)pKey;
+
+    sqlite3_free(aCell);
+    rc = nodeAcquire(pRtree, iBest, pNode, &pChild);
+    nodeRelease(pRtree, pNode);
+    pNode = pChild;
   }
-  new_elem->nKey = nKey;
-  pH->count++;
-  if( pH->htsize==0 ){
-    fts3Rehash(pH,8);
-    if( pH->htsize==0 ){
-      pH->count = 0;
-      fts3HashFree(new_elem);
-      return data;
+
+  *ppLeaf = pNode;
+  return rc;
+}
+
+/*
+** A cell with the same content as pCell has just been inserted into
+** the node pNode. This function updates the bounding box cells in
+** all ancestor elements.
+*/
+static void AdjustTree(
+  Rtree *pRtree,                    /* Rtree table */
+  RtreeNode *pNode,                 /* Adjust ancestry of this node. */
+  RtreeCell *pCell                  /* This cell was just inserted */
+){
+  RtreeNode *p = pNode;
+  while( p->pParent ){
+    RtreeCell cell;
+    RtreeNode *pParent = p->pParent;
+    int iCell = nodeParentIndex(pRtree, p);
+
+    nodeGetCell(pRtree, pParent, iCell, &cell);
+    if( !cellContains(pRtree, &cell, pCell) ){
+      cellUnion(pRtree, &cell, pCell);
+      nodeOverwriteCell(pRtree, pParent, &cell, iCell);
     }
+ 
+    p = pParent;
   }
-  if( pH->count > pH->htsize ){
-    fts3Rehash(pH,pH->htsize*2);
-  }
-  assert( pH->htsize>0 );
-  assert( (pH->htsize & (pH->htsize-1))==0 );
-  h = hraw & (pH->htsize-1);
-  fts3HashInsertElement(pH, &pH->ht[h], new_elem);
-  new_elem->data = data;
-  return 0;
 }
 
-#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
-
-/************** End of fts3_hash.c *******************************************/
-/************** Begin file fts3_porter.c *************************************/
-/*
-** 2006 September 30
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** Implementation of the full-text-search tokenizer that implements
-** a Porter stemmer.
+/*
+** Write mapping (iRowid->iNode) to the _rowid table.
 */
+static int rowidWrite(Rtree *pRtree, sqlite3_int64 iRowid, sqlite3_int64 iNode){
+  sqlite3_bind_int64(pRtree->pWriteRowid, 1, iRowid);
+  sqlite3_bind_int64(pRtree->pWriteRowid, 2, iNode);
+  sqlite3_step(pRtree->pWriteRowid);
+  return sqlite3_reset(pRtree->pWriteRowid);
+}
 
 /*
-** The code in this file is only compiled if:
-**
-**     * The FTS3 module is being built as an extension
-**       (in which case SQLITE_CORE is not defined), or
-**
-**     * The FTS3 module is being built into the core of
-**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
+** Write mapping (iNode->iPar) to the _parent table.
 */
-#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
+static int parentWrite(Rtree *pRtree, sqlite3_int64 iNode, sqlite3_int64 iPar){
+  sqlite3_bind_int64(pRtree->pWriteParent, 1, iNode);
+  sqlite3_bind_int64(pRtree->pWriteParent, 2, iPar);
+  sqlite3_step(pRtree->pWriteParent);
+  return sqlite3_reset(pRtree->pWriteParent);
+}
+
+static int rtreeInsertCell(Rtree *, RtreeNode *, RtreeCell *, int);
+
+#if VARIANT_GUTTMAN_LINEAR_SPLIT
+/*
+** Implementation of the linear variant of the PickNext() function from
+** Guttman[84].
+*/
+static RtreeCell *LinearPickNext(
+  Rtree *pRtree,
+  RtreeCell *aCell, 
+  int nCell, 
+  RtreeCell *pLeftBox, 
+  RtreeCell *pRightBox,
+  int *aiUsed
+){
+  int ii;
+  for(ii=0; aiUsed[ii]; ii++);
+  aiUsed[ii] = 1;
+  return &aCell[ii];
+}
+
+/*
+** Implementation of the linear variant of the PickSeeds() function from
+** Guttman[84].
+*/
+static void LinearPickSeeds(
+  Rtree *pRtree,
+  RtreeCell *aCell, 
+  int nCell, 
+  int *piLeftSeed, 
+  int *piRightSeed
+){
+  int i;
+  int iLeftSeed = 0;
+  int iRightSeed = 1;
+  float maxNormalInnerWidth = 0.0;
+
+  /* Pick two "seed" cells from the array of cells. The algorithm used
+  ** here is the LinearPickSeeds algorithm from Gutman[1984]. The 
+  ** indices of the two seed cells in the array are stored in local
+  ** variables iLeftSeek and iRightSeed.
+  */
+  for(i=0; inDim; i++){
+    float x1 = aCell[0].aCoord[i*2];
+    float x2 = aCell[0].aCoord[i*2+1];
+    float x3 = x1;
+    float x4 = x2;
+    int jj;
+
+    int iCellLeft = 0;
+    int iCellRight = 0;
 
+    for(jj=1; jjx4 ) x4 = right;
+      if( left>x3 ){
+        x3 = left;
+        iCellRight = jj;
+      }
+      if( rightmaxNormalInnerWidth ){
+        iLeftSeed = iCellLeft;
+        iRightSeed = iCellRight;
+      }
+    }
+  }
 
+  *piLeftSeed = iLeftSeed;
+  *piRightSeed = iRightSeed;
+}
+#endif /* VARIANT_GUTTMAN_LINEAR_SPLIT */
 
+#if VARIANT_GUTTMAN_QUADRATIC_SPLIT
 /*
-** Class derived from sqlite3_tokenizer
+** Implementation of the quadratic variant of the PickNext() function from
+** Guttman[84].
 */
-typedef struct porter_tokenizer {
-  sqlite3_tokenizer base;      /* Base class */
-} porter_tokenizer;
+static RtreeCell *QuadraticPickNext(
+  Rtree *pRtree,
+  RtreeCell *aCell, 
+  int nCell, 
+  RtreeCell *pLeftBox, 
+  RtreeCell *pRightBox,
+  int *aiUsed
+){
+  #define FABS(a) ((a)<0.0?-1.0*(a):(a))
+
+  int iSelect = -1;
+  float fDiff;
+  int ii;
+  for(ii=0; iifDiff ){
+        fDiff = diff;
+        iSelect = ii;
+      }
+    }
+  }
+  aiUsed[iSelect] = 1;
+  return &aCell[iSelect];
+}
 
 /*
-** Class derived from sqlit3_tokenizer_cursor
+** Implementation of the quadratic variant of the PickSeeds() function from
+** Guttman[84].
 */
-typedef struct porter_tokenizer_cursor {
-  sqlite3_tokenizer_cursor base;
-  const char *zInput;          /* input we are tokenizing */
-  int nInput;                  /* size of the input */
-  int iOffset;                 /* current position in zInput */
-  int iToken;                  /* index of next token to be returned */
-  char *zToken;                /* storage for current token */
-  int nAllocated;              /* space allocated to zToken buffer */
-} porter_tokenizer_cursor;
+static void QuadraticPickSeeds(
+  Rtree *pRtree,
+  RtreeCell *aCell, 
+  int nCell, 
+  int *piLeftSeed, 
+  int *piRightSeed
+){
+  int ii;
+  int jj;
 
+  int iLeftSeed = 0;
+  int iRightSeed = 1;
+  float fWaste = 0.0;
 
-/* Forward declaration */
-static const sqlite3_tokenizer_module porterTokenizerModule;
+  for(ii=0; iifWaste ){
+        iLeftSeed = ii;
+        iRightSeed = jj;
+        fWaste = waste;
+      }
+    }
+  }
 
+  *piLeftSeed = iLeftSeed;
+  *piRightSeed = iRightSeed;
+}
+#endif /* VARIANT_GUTTMAN_QUADRATIC_SPLIT */
 
 /*
-** Create a new tokenizer instance.
+** Arguments aIdx, aDistance and aSpare all point to arrays of size
+** nIdx. The aIdx array contains the set of integers from 0 to 
+** (nIdx-1) in no particular order. This function sorts the values
+** in aIdx according to the indexed values in aDistance. For
+** example, assuming the inputs:
+**
+**   aIdx      = { 0,   1,   2,   3 }
+**   aDistance = { 5.0, 2.0, 7.0, 6.0 }
+**
+** this function sets the aIdx array to contain:
+**
+**   aIdx      = { 0,   1,   2,   3 }
+**
+** The aSpare array is used as temporary working space by the
+** sorting algorithm.
 */
-static int porterCreate(
-  int argc, const char * const *argv,
-  sqlite3_tokenizer **ppTokenizer
+static void SortByDistance(
+  int *aIdx, 
+  int nIdx, 
+  float *aDistance, 
+  int *aSpare
 ){
-  porter_tokenizer *t;
-  t = (porter_tokenizer *) sqlite3_malloc(sizeof(*t));
-  if( t==NULL ) return SQLITE_NOMEM;
-  memset(t, 0, sizeof(*t));
-  *ppTokenizer = &t->base;
-  return SQLITE_OK;
+  if( nIdx>1 ){
+    int iLeft = 0;
+    int iRight = 0;
+
+    int nLeft = nIdx/2;
+    int nRight = nIdx-nLeft;
+    int *aLeft = aIdx;
+    int *aRight = &aIdx[nLeft];
+
+    SortByDistance(aLeft, nLeft, aDistance, aSpare);
+    SortByDistance(aRight, nRight, aDistance, aSpare);
+
+    memcpy(aSpare, aLeft, sizeof(int)*nLeft);
+    aLeft = aSpare;
+
+    while( iLeft1 ){
+
+    int iLeft = 0;
+    int iRight = 0;
+
+    int nLeft = nIdx/2;
+    int nRight = nIdx-nLeft;
+    int *aLeft = aIdx;
+    int *aRight = &aIdx[nLeft];
+
+    SortByDimension(pRtree, aLeft, nLeft, iDim, aCell, aSpare);
+    SortByDimension(pRtree, aRight, nRight, iDim, aCell, aSpare);
+
+    memcpy(aSpare, aLeft, sizeof(int)*nLeft);
+    aLeft = aSpare;
+    while( iLeftzInput = zInput;
-  if( zInput==0 ){
-    c->nInput = 0;
-  }else if( nInput<0 ){
-    c->nInput = (int)strlen(zInput);
-  }else{
-    c->nInput = nInput;
+  int nByte = (pRtree->nDim+1)*(sizeof(int*)+nCell*sizeof(int));
+
+  aaSorted = (int **)sqlite3_malloc(nByte);
+  if( !aaSorted ){
+    return SQLITE_NOMEM;
   }
-  c->iOffset = 0;                 /* start tokenizing at the beginning */
-  c->iToken = 0;
-  c->zToken = NULL;               /* no space allocated, yet. */
-  c->nAllocated = 0;
 
-  *ppCursor = &c->base;
+  aSpare = &((int *)&aaSorted[pRtree->nDim])[pRtree->nDim*nCell];
+  memset(aaSorted, 0, nByte);
+  for(ii=0; iinDim; ii++){
+    int jj;
+    aaSorted[ii] = &((int *)&aaSorted[pRtree->nDim])[ii*nCell];
+    for(jj=0; jjnDim; ii++){
+    float margin = 0.0;
+    float fBestOverlap;
+    float fBestArea;
+    int iBestLeft;
+    int nLeft;
+
+    for(
+      nLeft=RTREE_MINCELLS(pRtree); 
+      nLeft<=(nCell-RTREE_MINCELLS(pRtree)); 
+      nLeft++
+    ){
+      RtreeCell left;
+      RtreeCell right;
+      int kk;
+      float overlap;
+      float area;
+
+      memcpy(&left, &aCell[aaSorted[ii][0]], sizeof(RtreeCell));
+      memcpy(&right, &aCell[aaSorted[ii][nCell-1]], sizeof(RtreeCell));
+      for(kk=1; kk<(nCell-1); kk++){
+        if( kkzToken);
-  sqlite3_free(c);
+static int splitNodeGuttman(
+  Rtree *pRtree,
+  RtreeCell *aCell,
+  int nCell,
+  RtreeNode *pLeft,
+  RtreeNode *pRight,
+  RtreeCell *pBboxLeft,
+  RtreeCell *pBboxRight
+){
+  int iLeftSeed = 0;
+  int iRightSeed = 1;
+  int *aiUsed;
+  int i;
+
+  aiUsed = sqlite3_malloc(sizeof(int)*nCell);
+  memset(aiUsed, 0, sizeof(int)*nCell);
+
+  PickSeeds(pRtree, aCell, nCell, &iLeftSeed, &iRightSeed);
+
+  memcpy(pBboxLeft, &aCell[iLeftSeed], sizeof(RtreeCell));
+  memcpy(pBboxRight, &aCell[iRightSeed], sizeof(RtreeCell));
+  nodeInsertCell(pRtree, pLeft, &aCell[iLeftSeed]);
+  nodeInsertCell(pRtree, pRight, &aCell[iRightSeed]);
+  aiUsed[iLeftSeed] = 1;
+  aiUsed[iRightSeed] = 1;
+
+  for(i=nCell-2; i>0; i--){
+    RtreeCell *pNext;
+    pNext = PickNext(pRtree, aCell, nCell, pBboxLeft, pBboxRight, aiUsed);
+    float diff =  
+      cellGrowth(pRtree, pBboxLeft, pNext) - 
+      cellGrowth(pRtree, pBboxRight, pNext)
+    ;
+    if( (RTREE_MINCELLS(pRtree)-NCELL(pRight)==i)
+     || (diff>0.0 && (RTREE_MINCELLS(pRtree)-NCELL(pLeft)!=i))
+    ){
+      nodeInsertCell(pRtree, pRight, pNext);
+      cellUnion(pRtree, pBboxRight, pNext);
+    }else{
+      nodeInsertCell(pRtree, pLeft, pNext);
+      cellUnion(pRtree, pBboxLeft, pNext);
+    }
+  }
+
+  sqlite3_free(aiUsed);
   return SQLITE_OK;
 }
-/*
-** Vowel or consonant
-*/
-static const char cType[] = {
-   0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0,
-   1, 1, 1, 2, 1
-};
+#endif
 
-/*
-** isConsonant() and isVowel() determine if their first character in
-** the string they point to is a consonant or a vowel, according
-** to Porter ruls.  
-**
-** A consonate is any letter other than 'a', 'e', 'i', 'o', or 'u'.
-** 'Y' is a consonant unless it follows another consonant,
-** in which case it is a vowel.
-**
-** In these routine, the letters are in reverse order.  So the 'y' rule
-** is that 'y' is a consonant unless it is followed by another
-** consonent.
-*/
-static int isVowel(const char*);
-static int isConsonant(const char *z){
-  int j;
-  char x = *z;
-  if( x==0 ) return 0;
-  assert( x>='a' && x<='z' );
-  j = cType[x-'a'];
-  if( j<2 ) return j;
-  return z[1]==0 || isVowel(z + 1);
+static int updateMapping(
+  Rtree *pRtree, 
+  i64 iRowid, 
+  RtreeNode *pNode, 
+  int iHeight
+){
+  int (*xSetMapping)(Rtree *, sqlite3_int64, sqlite3_int64);
+  xSetMapping = ((iHeight==0)?rowidWrite:parentWrite);
+  if( iHeight>0 ){
+    RtreeNode *pChild = nodeHashLookup(pRtree, iRowid);
+    if( pChild ){
+      nodeRelease(pRtree, pChild->pParent);
+      nodeReference(pNode);
+      pChild->pParent = pNode;
+    }
+  }
+  return xSetMapping(pRtree, iRowid, pNode->iNode);
 }
-static int isVowel(const char *z){
-  int j;
-  char x = *z;
-  if( x==0 ) return 0;
-  assert( x>='a' && x<='z' );
-  j = cType[x-'a'];
-  if( j<2 ) return 1-j;
-  return isConsonant(z + 1);
+
+static int SplitNode(
+  Rtree *pRtree,
+  RtreeNode *pNode,
+  RtreeCell *pCell,
+  int iHeight
+){
+  int i;
+  int newCellIsRight = 0;
+
+  int rc = SQLITE_OK;
+  int nCell = NCELL(pNode);
+  RtreeCell *aCell;
+  int *aiUsed;
+
+  RtreeNode *pLeft = 0;
+  RtreeNode *pRight = 0;
+
+  RtreeCell leftbbox;
+  RtreeCell rightbbox;
+
+  /* Allocate an array and populate it with a copy of pCell and 
+  ** all cells from node pLeft. Then zero the original node.
+  */
+  aCell = sqlite3_malloc((sizeof(RtreeCell)+sizeof(int))*(nCell+1));
+  if( !aCell ){
+    rc = SQLITE_NOMEM;
+    goto splitnode_out;
+  }
+  aiUsed = (int *)&aCell[nCell+1];
+  memset(aiUsed, 0, sizeof(int)*(nCell+1));
+  for(i=0; iiNode==1 ){
+    pRight = nodeNew(pRtree, pNode, 1);
+    pLeft = nodeNew(pRtree, pNode, 1);
+    pRtree->iDepth++;
+    pNode->isDirty = 1;
+    writeInt16(pNode->zData, pRtree->iDepth);
+  }else{
+    pLeft = pNode;
+    pRight = nodeNew(pRtree, pLeft->pParent, 1);
+    nodeReference(pLeft);
+  }
+
+  if( !pLeft || !pRight ){
+    rc = SQLITE_NOMEM;
+    goto splitnode_out;
+  }
+
+  memset(pLeft->zData, 0, pRtree->iNodeSize);
+  memset(pRight->zData, 0, pRtree->iNodeSize);
+
+  rc = AssignCells(pRtree, aCell, nCell, pLeft, pRight, &leftbbox, &rightbbox);
+  if( rc!=SQLITE_OK ){
+    goto splitnode_out;
+  }
+
+  /* Ensure both child nodes have node numbers assigned to them. */
+  if( (0==pRight->iNode && SQLITE_OK!=(rc = nodeWrite(pRtree, pRight)))
+   || (0==pLeft->iNode && SQLITE_OK!=(rc = nodeWrite(pRtree, pLeft)))
+  ){
+    goto splitnode_out;
+  }
+
+  rightbbox.iRowid = pRight->iNode;
+  leftbbox.iRowid = pLeft->iNode;
+
+  if( pNode->iNode==1 ){
+    rc = rtreeInsertCell(pRtree, pLeft->pParent, &leftbbox, iHeight+1);
+    if( rc!=SQLITE_OK ){
+      goto splitnode_out;
+    }
+  }else{
+    RtreeNode *pParent = pLeft->pParent;
+    int iCell = nodeParentIndex(pRtree, pLeft);
+    nodeOverwriteCell(pRtree, pParent, &leftbbox, iCell);
+    AdjustTree(pRtree, pParent, &leftbbox);
+  }
+  if( (rc = rtreeInsertCell(pRtree, pRight->pParent, &rightbbox, iHeight+1)) ){
+    goto splitnode_out;
+  }
+
+  for(i=0; iiRowid ){
+      newCellIsRight = 1;
+    }
+    if( rc!=SQLITE_OK ){
+      goto splitnode_out;
+    }
+  }
+  if( pNode->iNode==1 ){
+    for(i=0; iiRowid, pLeft, iHeight);
+  }
+
+  if( rc==SQLITE_OK ){
+    rc = nodeRelease(pRtree, pRight);
+    pRight = 0;
+  }
+  if( rc==SQLITE_OK ){
+    rc = nodeRelease(pRtree, pLeft);
+    pLeft = 0;
+  }
+
+splitnode_out:
+  nodeRelease(pRtree, pRight);
+  nodeRelease(pRtree, pLeft);
+  sqlite3_free(aCell);
+  return rc;
 }
 
-/*
-** Let any sequence of one or more vowels be represented by V and let
-** C be sequence of one or more consonants.  Then every word can be
-** represented as:
-**
-**           [C] (VC){m} [V]
-**
-** In prose:  A word is an optional consonant followed by zero or
-** vowel-consonant pairs followed by an optional vowel.  "m" is the
-** number of vowel consonant pairs.  This routine computes the value
-** of m for the first i bytes of a word.
-**
-** Return true if the m-value for z is 1 or more.  In other words,
-** return true if z contains at least one vowel that is followed
-** by a consonant.
-**
-** In this routine z[] is in reverse order.  So we are really looking
-** for an instance of of a consonant followed by a vowel.
-*/
-static int m_gt_0(const char *z){
-  while( isVowel(z) ){ z++; }
-  if( *z==0 ) return 0;
-  while( isConsonant(z) ){ z++; }
-  return *z!=0;
+static int fixLeafParent(Rtree *pRtree, RtreeNode *pLeaf){
+  int rc = SQLITE_OK;
+  if( pLeaf->iNode!=1 && pLeaf->pParent==0 ){
+    sqlite3_bind_int64(pRtree->pReadParent, 1, pLeaf->iNode);
+    if( sqlite3_step(pRtree->pReadParent)==SQLITE_ROW ){
+      i64 iNode = sqlite3_column_int64(pRtree->pReadParent, 0);
+      rc = nodeAcquire(pRtree, iNode, 0, &pLeaf->pParent);
+    }else{
+      rc = SQLITE_ERROR;
+    }
+    sqlite3_reset(pRtree->pReadParent);
+    if( rc==SQLITE_OK ){
+      rc = fixLeafParent(pRtree, pLeaf->pParent);
+    }
+  }
+  return rc;
 }
 
-/* Like mgt0 above except we are looking for a value of m which is
-** exactly 1
-*/
-static int m_eq_1(const char *z){
-  while( isVowel(z) ){ z++; }
-  if( *z==0 ) return 0;
-  while( isConsonant(z) ){ z++; }
-  if( *z==0 ) return 0;
-  while( isVowel(z) ){ z++; }
-  if( *z==0 ) return 1;
-  while( isConsonant(z) ){ z++; }
-  return *z==0;
+static int deleteCell(Rtree *, RtreeNode *, int, int);
+
+static int removeNode(Rtree *pRtree, RtreeNode *pNode, int iHeight){
+  int rc;
+  RtreeNode *pParent;
+  int iCell;
+
+  assert( pNode->nRef==1 );
+
+  /* Remove the entry in the parent cell. */
+  iCell = nodeParentIndex(pRtree, pNode);
+  pParent = pNode->pParent;
+  pNode->pParent = 0;
+  if( SQLITE_OK!=(rc = deleteCell(pRtree, pParent, iCell, iHeight+1)) 
+   || SQLITE_OK!=(rc = nodeRelease(pRtree, pParent))
+  ){
+    return rc;
+  }
+
+  /* Remove the xxx_node entry. */
+  sqlite3_bind_int64(pRtree->pDeleteNode, 1, pNode->iNode);
+  sqlite3_step(pRtree->pDeleteNode);
+  if( SQLITE_OK!=(rc = sqlite3_reset(pRtree->pDeleteNode)) ){
+    return rc;
+  }
+
+  /* Remove the xxx_parent entry. */
+  sqlite3_bind_int64(pRtree->pDeleteParent, 1, pNode->iNode);
+  sqlite3_step(pRtree->pDeleteParent);
+  if( SQLITE_OK!=(rc = sqlite3_reset(pRtree->pDeleteParent)) ){
+    return rc;
+  }
+  
+  /* Remove the node from the in-memory hash table and link it into
+  ** the Rtree.pDeleted list. Its contents will be re-inserted later on.
+  */
+  nodeHashDelete(pRtree, pNode);
+  pNode->iNode = iHeight;
+  pNode->pNext = pRtree->pDeleted;
+  pNode->nRef++;
+  pRtree->pDeleted = pNode;
+
+  return SQLITE_OK;
 }
 
-/* Like mgt0 above except we are looking for a value of m>1 instead
-** or m>0
-*/
-static int m_gt_1(const char *z){
-  while( isVowel(z) ){ z++; }
-  if( *z==0 ) return 0;
-  while( isConsonant(z) ){ z++; }
-  if( *z==0 ) return 0;
-  while( isVowel(z) ){ z++; }
-  if( *z==0 ) return 0;
-  while( isConsonant(z) ){ z++; }
-  return *z!=0;
+static void fixBoundingBox(Rtree *pRtree, RtreeNode *pNode){
+  RtreeNode *pParent = pNode->pParent;
+  if( pParent ){
+    int ii; 
+    int nCell = NCELL(pNode);
+    RtreeCell box;                            /* Bounding box for pNode */
+    nodeGetCell(pRtree, pNode, 0, &box);
+    for(ii=1; iiiNode;
+    ii = nodeParentIndex(pRtree, pNode);
+    nodeOverwriteCell(pRtree, pParent, &box, ii);
+    fixBoundingBox(pRtree, pParent);
+  }
 }
 
 /*
-** Return TRUE if there is a vowel anywhere within z[0..n-1]
+** Delete the cell at index iCell of node pNode. After removing the
+** cell, adjust the r-tree data structure if required.
 */
-static int hasVowel(const char *z){
-  while( isConsonant(z) ){ z++; }
-  return *z!=0;
+static int deleteCell(Rtree *pRtree, RtreeNode *pNode, int iCell, int iHeight){
+  int rc;
+
+  if( SQLITE_OK!=(rc = fixLeafParent(pRtree, pNode)) ){
+    return rc;
+  }
+
+  /* Remove the cell from the node. This call just moves bytes around
+  ** the in-memory node image, so it cannot fail.
+  */
+  nodeDeleteCell(pRtree, pNode, iCell);
+
+  /* If the node is not the tree root and now has less than the minimum
+  ** number of cells, remove it from the tree. Otherwise, update the
+  ** cell in the parent node so that it tightly contains the updated
+  ** node.
+  */
+  if( pNode->iNode!=1 ){
+    RtreeNode *pParent = pNode->pParent;
+    if( (pParent->iNode!=1 || NCELL(pParent)!=1) 
+     && (NCELL(pNode)nDim; iDim++){
+      aCenterCoord[iDim] += DCOORD(aCell[ii].aCoord[iDim*2]);
+      aCenterCoord[iDim] += DCOORD(aCell[ii].aCoord[iDim*2+1]);
+    }
+  }
+  for(iDim=0; iDimnDim; iDim++){
+    aCenterCoord[iDim] = aCenterCoord[iDim]/((float)nCell*2.0);
+  }
+
+  for(ii=0; iinDim; iDim++){
+      float coord = DCOORD(aCell[ii].aCoord[iDim*2+1]) - 
+          DCOORD(aCell[ii].aCoord[iDim*2]);
+      aDistance[ii] += (coord-aCenterCoord[iDim])*(coord-aCenterCoord[iDim]);
+    }
+  }
+
+  SortByDistance(aOrder, nCell, aDistance, aSpare);
+  nodeZero(pRtree, pNode);
+
+  for(ii=0; rc==SQLITE_OK && ii<(nCell-(RTREE_MINCELLS(pRtree)+1)); ii++){
+    RtreeCell *p = &aCell[aOrder[ii]];
+    nodeInsertCell(pRtree, pNode, p);
+    if( p->iRowid==pCell->iRowid ){
+      if( iHeight==0 ){
+        rc = rowidWrite(pRtree, p->iRowid, pNode->iNode);
+      }else{
+        rc = parentWrite(pRtree, p->iRowid, pNode->iNode);
+      }
+    }
+  }
+  if( rc==SQLITE_OK ){
+    fixBoundingBox(pRtree, pNode);
+  }
+  for(; rc==SQLITE_OK && iiiNode currently contains
+    ** the height of the sub-tree headed by the cell.
+    */
+    RtreeNode *pInsert;
+    RtreeCell *p = &aCell[aOrder[ii]];
+    rc = ChooseLeaf(pRtree, p, iHeight, &pInsert);
+    if( rc==SQLITE_OK ){
+      int rc2;
+      rc = rtreeInsertCell(pRtree, pInsert, p, iHeight);
+      rc2 = nodeRelease(pRtree, pInsert);
+      if( rc==SQLITE_OK ){
+        rc = rc2;
+      }
+    }
+  }
+
+  sqlite3_free(aCell);
+  return rc;
 }
 
 /*
-** Return TRUE if the word ends with three letters which
-** are consonant-vowel-consonent and where the final consonant
-** is not 'w', 'x', or 'y'.
-**
-** The word is reversed here.  So we are really checking the
-** first three letters and the first one cannot be in [wxy].
+** Insert cell pCell into node pNode. Node pNode is the head of a 
+** subtree iHeight high (leaf nodes have iHeight==0).
 */
-static int star_oh(const char *z){
-  return
-    z[0]!=0 && isConsonant(z) &&
-    z[0]!='w' && z[0]!='x' && z[0]!='y' &&
-    z[1]!=0 && isVowel(z+1) &&
-    z[2]!=0 && isConsonant(z+2);
+static int rtreeInsertCell(
+  Rtree *pRtree,
+  RtreeNode *pNode,
+  RtreeCell *pCell,
+  int iHeight
+){
+  int rc = SQLITE_OK;
+  if( iHeight>0 ){
+    RtreeNode *pChild = nodeHashLookup(pRtree, pCell->iRowid);
+    if( pChild ){
+      nodeRelease(pRtree, pChild->pParent);
+      nodeReference(pNode);
+      pChild->pParent = pNode;
+    }
+  }
+  if( nodeInsertCell(pRtree, pNode, pCell) ){
+#if VARIANT_RSTARTREE_REINSERT
+    if( iHeight<=pRtree->iReinsertHeight || pNode->iNode==1){
+      rc = SplitNode(pRtree, pNode, pCell, iHeight);
+    }else{
+      pRtree->iReinsertHeight = iHeight;
+      rc = Reinsert(pRtree, pNode, pCell, iHeight);
+    }
+#else
+    rc = SplitNode(pRtree, pNode, pCell, iHeight);
+#endif
+  }else{
+    AdjustTree(pRtree, pNode, pCell);
+    if( iHeight==0 ){
+      rc = rowidWrite(pRtree, pCell->iRowid, pNode->iNode);
+    }else{
+      rc = parentWrite(pRtree, pCell->iRowid, pNode->iNode);
+    }
+  }
+  return rc;
+}
+
+static int reinsertNodeContent(Rtree *pRtree, RtreeNode *pNode){
+  int ii;
+  int rc = SQLITE_OK;
+  int nCell = NCELL(pNode);
+
+  for(ii=0; rc==SQLITE_OK && iiiNode currently contains
+    ** the height of the sub-tree headed by the cell.
+    */
+    rc = ChooseLeaf(pRtree, &cell, pNode->iNode, &pInsert);
+    if( rc==SQLITE_OK ){
+      int rc2;
+      rc = rtreeInsertCell(pRtree, pInsert, &cell, pNode->iNode);
+      rc2 = nodeRelease(pRtree, pInsert);
+      if( rc==SQLITE_OK ){
+        rc = rc2;
+      }
+    }
+  }
+  return rc;
 }
 
 /*
-** If the word ends with zFrom and xCond() is true for the stem
-** of the word that preceeds the zFrom ending, then change the 
-** ending to zTo.
-**
-** The input word *pz and zFrom are both in reverse order.  zTo
-** is in normal order. 
-**
-** Return TRUE if zFrom matches.  Return FALSE if zFrom does not
-** match.  Not that TRUE is returned even if xCond() fails and
-** no substitution occurs.
+** Select a currently unused rowid for a new r-tree record.
 */
-static int stem(
-  char **pz,             /* The word being stemmed (Reversed) */
-  const char *zFrom,     /* If the ending matches this... (Reversed) */
-  const char *zTo,       /* ... change the ending to this (not reversed) */
-  int (*xCond)(const char*)   /* Condition that must be true */
-){
-  char *z = *pz;
-  while( *zFrom && *zFrom==*z ){ z++; zFrom++; }
-  if( *zFrom!=0 ) return 0;
-  if( xCond && !xCond(z) ) return 1;
-  while( *zTo ){
-    *(--z) = *(zTo++);
+static int newRowid(Rtree *pRtree, i64 *piRowid){
+  int rc;
+  sqlite3_bind_null(pRtree->pWriteRowid, 1);
+  sqlite3_bind_null(pRtree->pWriteRowid, 2);
+  sqlite3_step(pRtree->pWriteRowid);
+  rc = sqlite3_reset(pRtree->pWriteRowid);
+  *piRowid = sqlite3_last_insert_rowid(pRtree->db);
+  return rc;
+}
+
+#ifndef NDEBUG
+static int hashIsEmpty(Rtree *pRtree){
+  int ii;
+  for(ii=0; iiaHash[ii] );
   }
-  *pz = z;
   return 1;
 }
+#endif
 
 /*
-** This is the fallback stemmer used when the porter stemmer is
-** inappropriate.  The input word is copied into the output with
-** US-ASCII case folding.  If the input word is too long (more
-** than 20 bytes if it contains no digits or more than 6 bytes if
-** it contains digits) then word is truncated to 20 or 6 bytes
-** by taking 10 or 3 bytes from the beginning and end.
+** The xUpdate method for rtree module virtual tables.
 */
-static void copy_stemmer(const char *zIn, int nIn, char *zOut, int *pnOut){
-  int i, mx, j;
-  int hasDigit = 0;
-  for(i=0; i='A' && c<='Z' ){
-      zOut[i] = c - 'A' + 'a';
+int rtreeUpdate(
+  sqlite3_vtab *pVtab, 
+  int nData, 
+  sqlite3_value **azData, 
+  sqlite_int64 *pRowid
+){
+  Rtree *pRtree = (Rtree *)pVtab;
+  int rc = SQLITE_OK;
+
+  rtreeReference(pRtree);
+
+  assert(nData>=1);
+  assert(hashIsEmpty(pRtree));
+
+  /* If azData[0] is not an SQL NULL value, it is the rowid of a
+  ** record to delete from the r-tree table. The following block does
+  ** just that.
+  */
+  if( sqlite3_value_type(azData[0])!=SQLITE_NULL ){
+    i64 iDelete;                /* The rowid to delete */
+    RtreeNode *pLeaf;           /* Leaf node containing record iDelete */
+    int iCell;                  /* Index of iDelete cell in pLeaf */
+    RtreeNode *pRoot;
+
+    /* Obtain a reference to the root node to initialise Rtree.iDepth */
+    rc = nodeAcquire(pRtree, 1, 0, &pRoot);
+
+    /* Obtain a reference to the leaf node that contains the entry 
+    ** about to be deleted. 
+    */
+    if( rc==SQLITE_OK ){
+      iDelete = sqlite3_value_int64(azData[0]);
+      rc = findLeafNode(pRtree, iDelete, &pLeaf);
+    }
+
+    /* Delete the cell in question from the leaf node. */
+    if( rc==SQLITE_OK ){
+      int rc2;
+      iCell = nodeRowidIndex(pRtree, pLeaf, iDelete);
+      rc = deleteCell(pRtree, pLeaf, iCell, 0);
+      rc2 = nodeRelease(pRtree, pLeaf);
+      if( rc==SQLITE_OK ){
+        rc = rc2;
+      }
+    }
+
+    /* Delete the corresponding entry in the _rowid table. */
+    if( rc==SQLITE_OK ){
+      sqlite3_bind_int64(pRtree->pDeleteRowid, 1, iDelete);
+      sqlite3_step(pRtree->pDeleteRowid);
+      rc = sqlite3_reset(pRtree->pDeleteRowid);
+    }
+
+    /* Check if the root node now has exactly one child. If so, remove
+    ** it, schedule the contents of the child for reinsertion and 
+    ** reduce the tree height by one.
+    **
+    ** This is equivalent to copying the contents of the child into
+    ** the root node (the operation that Gutman's paper says to perform 
+    ** in this scenario).
+    */
+    if( rc==SQLITE_OK && pRtree->iDepth>0 ){
+      if( rc==SQLITE_OK && NCELL(pRoot)==1 ){
+        RtreeNode *pChild;
+        i64 iChild = nodeGetRowid(pRtree, pRoot, 0);
+        rc = nodeAcquire(pRtree, iChild, pRoot, &pChild);
+        if( rc==SQLITE_OK ){
+          rc = removeNode(pRtree, pChild, pRtree->iDepth-1);
+        }
+        if( rc==SQLITE_OK ){
+          pRtree->iDepth--;
+          writeInt16(pRoot->zData, pRtree->iDepth);
+          pRoot->isDirty = 1;
+        }
+      }
+    }
+
+    /* Re-insert the contents of any underfull nodes removed from the tree. */
+    for(pLeaf=pRtree->pDeleted; pLeaf; pLeaf=pRtree->pDeleted){
+      if( rc==SQLITE_OK ){
+        rc = reinsertNodeContent(pRtree, pLeaf);
+      }
+      pRtree->pDeleted = pLeaf->pNext;
+      sqlite3_free(pLeaf);
+    }
+
+    /* Release the reference to the root node. */
+    if( rc==SQLITE_OK ){
+      rc = nodeRelease(pRtree, pRoot);
+    }else{
+      nodeRelease(pRtree, pRoot);
+    }
+  }
+
+  /* If the azData[] array contains more than one element, elements
+  ** (azData[2]..azData[argc-1]) contain a new record to insert into
+  ** the r-tree structure.
+  */
+  if( rc==SQLITE_OK && nData>1 ){
+    /* Insert a new record into the r-tree */
+    RtreeCell cell;
+    int ii;
+    RtreeNode *pLeaf;
+
+    /* Populate the cell.aCoord[] array. The first coordinate is azData[3]. */
+    assert( nData==(pRtree->nDim*2 + 3) );
+    if( pRtree->eCoordType==RTREE_COORD_REAL32 ){
+      for(ii=0; ii<(pRtree->nDim*2); ii+=2){
+        cell.aCoord[ii].f = (float)sqlite3_value_double(azData[ii+3]);
+        cell.aCoord[ii+1].f = (float)sqlite3_value_double(azData[ii+4]);
+        if( cell.aCoord[ii].f>cell.aCoord[ii+1].f ){
+          rc = SQLITE_CONSTRAINT;
+          goto constraint;
+        }
+      }
     }else{
-      if( c>='0' && c<='9' ) hasDigit = 1;
-      zOut[i] = c;
+      for(ii=0; ii<(pRtree->nDim*2); ii+=2){
+        cell.aCoord[ii].i = sqlite3_value_int(azData[ii+3]);
+        cell.aCoord[ii+1].i = sqlite3_value_int(azData[ii+4]);
+        if( cell.aCoord[ii].i>cell.aCoord[ii+1].i ){
+          rc = SQLITE_CONSTRAINT;
+          goto constraint;
+        }
+      }
     }
-  }
-  mx = hasDigit ? 3 : 10;
-  if( nIn>mx*2 ){
-    for(j=mx, i=nIn-mx; ipReadRowid, 1, cell.iRowid);
+      if( SQLITE_ROW==sqlite3_step(pRtree->pReadRowid) ){
+        sqlite3_reset(pRtree->pReadRowid);
+        rc = SQLITE_CONSTRAINT;
+        goto constraint;
+      }
+      rc = sqlite3_reset(pRtree->pReadRowid);
+    }
+
+    if( rc==SQLITE_OK ){
+      rc = ChooseLeaf(pRtree, &cell, 0, &pLeaf);
+    }
+    if( rc==SQLITE_OK ){
+      int rc2;
+      pRtree->iReinsertHeight = -1;
+      rc = rtreeInsertCell(pRtree, pLeaf, &cell, 0);
+      rc2 = nodeRelease(pRtree, pLeaf);
+      if( rc==SQLITE_OK ){
+        rc = rc2;
+      }
     }
-    i = j;
   }
-  zOut[i] = 0;
-  *pnOut = i;
-}
 
+constraint:
+  rtreeRelease(pRtree);
+  return rc;
+}
 
 /*
-** Stem the input word zIn[0..nIn-1].  Store the output in zOut.
-** zOut is at least big enough to hold nIn bytes.  Write the actual
-** size of the output word (exclusive of the '\0' terminator) into *pnOut.
-**
-** Any upper-case characters in the US-ASCII character set ([A-Z])
-** are converted to lower case.  Upper-case UTF characters are
-** unchanged.
-**
-** Words that are longer than about 20 bytes are stemmed by retaining
-** a few bytes from the beginning and the end of the word.  If the
-** word contains digits, 3 bytes are taken from the beginning and
-** 3 bytes from the end.  For long words without digits, 10 bytes
-** are taken from each end.  US-ASCII case folding still applies.
-** 
-** If the input word contains not digits but does characters not 
-** in [a-zA-Z] then no stemming is attempted and this routine just 
-** copies the input into the input into the output with US-ASCII
-** case folding.
-**
-** Stemming never increases the length of the word.  So there is
-** no chance of overflowing the zOut buffer.
+** The xRename method for rtree module virtual tables.
 */
-static void porter_stemmer(const char *zIn, int nIn, char *zOut, int *pnOut){
-  int i, j, c;
-  char zReverse[28];
-  char *z, *z2;
-  if( nIn<3 || nIn>=sizeof(zReverse)-7 ){
-    /* The word is too big or too small for the porter stemmer.
-    ** Fallback to the copy stemmer */
-    copy_stemmer(zIn, nIn, zOut, pnOut);
-    return;
+static int rtreeRename(sqlite3_vtab *pVtab, const char *zNewName){
+  Rtree *pRtree = (Rtree *)pVtab;
+  int rc = SQLITE_NOMEM;
+  char *zSql = sqlite3_mprintf(
+    "ALTER TABLE %Q.'%q_node'   RENAME TO \"%w_node\";"
+    "ALTER TABLE %Q.'%q_parent' RENAME TO \"%w_parent\";"
+    "ALTER TABLE %Q.'%q_rowid'  RENAME TO \"%w_rowid\";"
+    , pRtree->zDb, pRtree->zName, zNewName 
+    , pRtree->zDb, pRtree->zName, zNewName 
+    , pRtree->zDb, pRtree->zName, zNewName
+  );
+  if( zSql ){
+    rc = sqlite3_exec(pRtree->db, zSql, 0, 0, 0);
+    sqlite3_free(zSql);
   }
-  for(i=0, j=sizeof(zReverse)-6; i='A' && c<='Z' ){
-      zReverse[j] = c + 'a' - 'A';
-    }else if( c>='a' && c<='z' ){
-      zReverse[j] = c;
-    }else{
-      /* The use of a character not in [a-zA-Z] means that we fallback
-      ** to the copy stemmer */
-      copy_stemmer(zIn, nIn, zOut, pnOut);
-      return;
+  return rc;
+}
+
+static sqlite3_module rtreeModule = {
+  0,                         /* iVersion */
+  rtreeCreate,                /* xCreate - create a table */
+  rtreeConnect,               /* xConnect - connect to an existing table */
+  rtreeBestIndex,             /* xBestIndex - Determine search strategy */
+  rtreeDisconnect,            /* xDisconnect - Disconnect from a table */
+  rtreeDestroy,               /* xDestroy - Drop a table */
+  rtreeOpen,                  /* xOpen - open a cursor */
+  rtreeClose,                 /* xClose - close a cursor */
+  rtreeFilter,                /* xFilter - configure scan constraints */
+  rtreeNext,                  /* xNext - advance a cursor */
+  rtreeEof,                   /* xEof */
+  rtreeColumn,                /* xColumn - read data */
+  rtreeRowid,                 /* xRowid - read data */
+  rtreeUpdate,                /* xUpdate - write data */
+  0,                          /* xBegin - begin transaction */
+  0,                          /* xSync - sync transaction */
+  0,                          /* xCommit - commit transaction */
+  0,                          /* xRollback - rollback transaction */
+  0,                          /* xFindFunction - function overloading */
+  rtreeRename                 /* xRename - rename the table */
+};
+
+static int rtreeSqlInit(
+  Rtree *pRtree, 
+  sqlite3 *db, 
+  const char *zDb, 
+  const char *zPrefix, 
+  int isCreate
+){
+  int rc = SQLITE_OK;
+
+  #define N_STATEMENT 9
+  static const char *azSql[N_STATEMENT] = {
+    /* Read and write the xxx_node table */
+    "SELECT data FROM '%q'.'%q_node' WHERE nodeno = :1",
+    "INSERT OR REPLACE INTO '%q'.'%q_node' VALUES(:1, :2)",
+    "DELETE FROM '%q'.'%q_node' WHERE nodeno = :1",
+
+    /* Read and write the xxx_rowid table */
+    "SELECT nodeno FROM '%q'.'%q_rowid' WHERE rowid = :1",
+    "INSERT OR REPLACE INTO '%q'.'%q_rowid' VALUES(:1, :2)",
+    "DELETE FROM '%q'.'%q_rowid' WHERE rowid = :1",
+
+    /* Read and write the xxx_parent table */
+    "SELECT parentnode FROM '%q'.'%q_parent' WHERE nodeno = :1",
+    "INSERT OR REPLACE INTO '%q'.'%q_parent' VALUES(:1, :2)",
+    "DELETE FROM '%q'.'%q_parent' WHERE nodeno = :1"
+  };
+  sqlite3_stmt **appStmt[N_STATEMENT];
+  int i;
+
+  pRtree->db = db;
+
+  if( isCreate ){
+    char *zCreate = sqlite3_mprintf(
+"CREATE TABLE \"%w\".\"%w_node\"(nodeno INTEGER PRIMARY KEY, data BLOB);"
+"CREATE TABLE \"%w\".\"%w_rowid\"(rowid INTEGER PRIMARY KEY, nodeno INTEGER);"
+"CREATE TABLE \"%w\".\"%w_parent\"(nodeno INTEGER PRIMARY KEY, parentnode INTEGER);"
+"INSERT INTO '%q'.'%q_node' VALUES(1, zeroblob(%d))",
+      zDb, zPrefix, zDb, zPrefix, zDb, zPrefix, zDb, zPrefix, pRtree->iNodeSize
+    );
+    if( !zCreate ){
+      return SQLITE_NOMEM;
+    }
+    rc = sqlite3_exec(db, zCreate, 0, 0, 0);
+    sqlite3_free(zCreate);
+    if( rc!=SQLITE_OK ){
+      return rc;
     }
   }
-  memset(&zReverse[sizeof(zReverse)-5], 0, 5);
-  z = &zReverse[j+1];
 
+  appStmt[0] = &pRtree->pReadNode;
+  appStmt[1] = &pRtree->pWriteNode;
+  appStmt[2] = &pRtree->pDeleteNode;
+  appStmt[3] = &pRtree->pReadRowid;
+  appStmt[4] = &pRtree->pWriteRowid;
+  appStmt[5] = &pRtree->pDeleteRowid;
+  appStmt[6] = &pRtree->pReadParent;
+  appStmt[7] = &pRtree->pWriteParent;
+  appStmt[8] = &pRtree->pDeleteParent;
 
-  /* Step 1a */
-  if( z[0]=='s' ){
-    if(
-     !stem(&z, "sess", "ss", 0) &&
-     !stem(&z, "sei", "i", 0)  &&
-     !stem(&z, "ss", "ss", 0)
-    ){
-      z++;
+  for(i=0; i module name
+**   argv[1]   -> database name
+**   argv[2]   -> table name
+**   argv[...] -> column names...
+*/
+static int rtreeInit(
+  sqlite3 *db,                        /* Database connection */
+  void *pAux,                         /* Pointer to head of rtree list */
+  int argc, const char *const*argv,   /* Parameters to CREATE TABLE statement */
+  sqlite3_vtab **ppVtab,              /* OUT: New virtual table */
+  char **pzErr,                       /* OUT: Error message, if any */
+  int isCreate,                       /* True for xCreate, false for xConnect */
+  int eCoordType                      /* One of the RTREE_COORD_* constants */
+){
+  int rc = SQLITE_OK;
+  int iPageSize = 0;
+  Rtree *pRtree;
+  int nDb;              /* Length of string argv[1] */
+  int nName;            /* Length of string argv[2] */
+
+  const char *aErrMsg[] = {
+    0,                                                    /* 0 */
+    "Wrong number of columns for an rtree table",         /* 1 */
+    "Too few columns for an rtree table",                 /* 2 */
+    "Too many columns for an rtree table"                 /* 3 */
+  };
+
+  int iErr = (argc<6) ? 2 : argc>(RTREE_MAX_DIMENSIONS*2+4) ? 3 : argc%2;
+  if( aErrMsg[iErr] ){
+    *pzErr = sqlite3_mprintf("%s", aErrMsg[iErr]);
+    return SQLITE_ERROR;
   }
 
-  /* Step 5a */
-  if( z[0]=='e' ){
-    if( m_gt_1(z+1) ){
-      z++;
-    }else if( m_eq_1(z+1) && !star_oh(z+1) ){
-      z++;
-    }
+  rc = getPageSize(db, argv[1], &iPageSize);
+  if( rc!=SQLITE_OK ){
+    return rc;
   }
 
-  /* Step 5b */
-  if( m_gt_1(z) && z[0]=='l' && z[1]=='l' ){
-    z++;
+  /* Allocate the sqlite3_vtab structure */
+  nDb = strlen(argv[1]);
+  nName = strlen(argv[2]);
+  pRtree = (Rtree *)sqlite3_malloc(sizeof(Rtree)+nDb+nName+2);
+  if( !pRtree ){
+    return SQLITE_NOMEM;
+  }
+  memset(pRtree, 0, sizeof(Rtree)+nDb+nName+2);
+  pRtree->nBusy = 1;
+  pRtree->base.pModule = &rtreeModule;
+  pRtree->zDb = (char *)&pRtree[1];
+  pRtree->zName = &pRtree->zDb[nDb+1];
+  pRtree->nDim = (argc-4)/2;
+  pRtree->nBytesPerCell = 8 + pRtree->nDim*4*2;
+  pRtree->eCoordType = eCoordType;
+  memcpy(pRtree->zDb, argv[1], nDb);
+  memcpy(pRtree->zName, argv[2], nName);
+
+  /* Figure out the node size to use. By default, use 64 bytes less than
+  ** the database page-size. This ensures that each node is stored on
+  ** a single database page.
+  **
+  ** If the databasd page-size is so large that more than RTREE_MAXCELLS
+  ** entries would fit in a single node, use a smaller node-size.
+  */
+  pRtree->iNodeSize = iPageSize-64;
+  if( (4+pRtree->nBytesPerCell*RTREE_MAXCELLS)iNodeSize ){
+    pRtree->iNodeSize = 4+pRtree->nBytesPerCell*RTREE_MAXCELLS;
   }
 
-  /* z[] is now the stemmed word in reverse order.  Flip it back
-  ** around into forward order and return.
+  /* Create/Connect to the underlying relational database schema. If
+  ** that is successful, call sqlite3_declare_vtab() to configure
+  ** the r-tree table schema.
   */
-  *pnOut = i = strlen(z);
-  zOut[i] = 0;
-  while( *z ){
-    zOut[--i] = *(z++);
+  if( (rc = rtreeSqlInit(pRtree, db, argv[1], argv[2], isCreate)) ){
+    *pzErr = sqlite3_mprintf("%s", sqlite3_errmsg(db));
+  }else{
+    char *zSql = sqlite3_mprintf("CREATE TABLE x(%s", argv[3]);
+    char *zTmp;
+    int ii;
+    for(ii=4; zSql && ii*2 coordinates.
 */
-static int porterNext(
-  sqlite3_tokenizer_cursor *pCursor,  /* Cursor returned by porterOpen */
-  const char **pzToken,               /* OUT: *pzToken is the token text */
-  int *pnBytes,                       /* OUT: Number of bytes in token */
-  int *piStartOffset,                 /* OUT: Starting offset of token */
-  int *piEndOffset,                   /* OUT: Ending offset of token */
-  int *piPosition                     /* OUT: Position integer of token */
-){
-  porter_tokenizer_cursor *c = (porter_tokenizer_cursor *) pCursor;
-  const char *z = c->zInput;
-
-  while( c->iOffsetnInput ){
-    int iStartOffset, ch;
-
-    /* Scan past delimiter characters */
-    while( c->iOffsetnInput && isDelim(z[c->iOffset]) ){
-      c->iOffset++;
-    }
+static void rtreenode(sqlite3_context *ctx, int nArg, sqlite3_value **apArg){
+  char *zText = 0;
+  RtreeNode node;
+  Rtree tree;
+  int ii;
 
-    /* Count non-delimiter characters. */
-    iStartOffset = c->iOffset;
-    while( c->iOffsetnInput && !isDelim(z[c->iOffset]) ){
-      c->iOffset++;
+  memset(&node, 0, sizeof(RtreeNode));
+  memset(&tree, 0, sizeof(Rtree));
+  tree.nDim = sqlite3_value_int(apArg[0]);
+  tree.nBytesPerCell = 8 + 8 * tree.nDim;
+  node.zData = (u8 *)sqlite3_value_blob(apArg[1]);
+
+  for(ii=0; iiiOffset>iStartOffset ){
-      int n = c->iOffset-iStartOffset;
-      if( n>c->nAllocated ){
-        c->nAllocated = n+20;
-        c->zToken = sqlite3_realloc(c->zToken, c->nAllocated);
-        if( c->zToken==NULL ) return SQLITE_NOMEM;
-      }
-      porter_stemmer(&z[iStartOffset], n, c->zToken, pnBytes);
-      *pzToken = c->zToken;
-      *piStartOffset = iStartOffset;
-      *piEndOffset = c->iOffset;
-      *piPosition = c->iToken++;
-      return SQLITE_OK;
-    }
+static void rtreedepth(sqlite3_context *ctx, int nArg, sqlite3_value **apArg){
+  if( sqlite3_value_type(apArg[0])!=SQLITE_BLOB 
+   || sqlite3_value_bytes(apArg[0])<2
+  ){
+    sqlite3_result_error(ctx, "Invalid argument to rtreedepth()", -1); 
+  }else{
+    u8 *zBlob = (u8 *)sqlite3_value_blob(apArg[0]);
+    sqlite3_result_int(ctx, readInt16(zBlob));
   }
-  return SQLITE_DONE;
 }
 
 /*
-** The set of routines that implement the porter-stemmer tokenizer
+** Register the r-tree module with database handle db. This creates the
+** virtual table module "rtree" and the debugging/analysis scalar 
+** function "rtreenode".
 */
-static const sqlite3_tokenizer_module porterTokenizerModule = {
-  0,
-  porterCreate,
-  porterDestroy,
-  porterOpen,
-  porterClose,
-  porterNext,
-};
+SQLITE_PRIVATE int sqlite3RtreeInit(sqlite3 *db){
+  int rc = SQLITE_OK;
 
-/*
-** Allocate a new porter tokenizer.  Return a pointer to the new
-** tokenizer in *ppModule
-*/
-SQLITE_PRIVATE void sqlite3Fts3PorterTokenizerModule(
-  sqlite3_tokenizer_module const**ppModule
+  if( rc==SQLITE_OK ){
+    int utf8 = SQLITE_UTF8;
+    rc = sqlite3_create_function(db, "rtreenode", 2, utf8, 0, rtreenode, 0, 0);
+  }
+  if( rc==SQLITE_OK ){
+    int utf8 = SQLITE_UTF8;
+    rc = sqlite3_create_function(db, "rtreedepth", 1, utf8, 0,rtreedepth, 0, 0);
+  }
+  if( rc==SQLITE_OK ){
+    void *c = (void *)RTREE_COORD_REAL32;
+    rc = sqlite3_create_module_v2(db, "rtree", &rtreeModule, c, 0);
+  }
+  if( rc==SQLITE_OK ){
+    void *c = (void *)RTREE_COORD_INT32;
+    rc = sqlite3_create_module_v2(db, "rtree_i32", &rtreeModule, c, 0);
+  }
+
+  return rc;
+}
+
+#if !SQLITE_CORE
+SQLITE_API int sqlite3_extension_init(
+  sqlite3 *db,
+  char **pzErrMsg,
+  const sqlite3_api_routines *pApi
 ){
-  *ppModule = &porterTokenizerModule;
+  SQLITE_EXTENSION_INIT2(pApi)
+  return sqlite3RtreeInit(db);
 }
+#endif
 
-#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
+#endif
 
-/************** End of fts3_porter.c *****************************************/
-/************** Begin file fts3_tokenizer.c **********************************/
+/************** End of rtree.c ***********************************************/
+/************** Begin file icu.c *********************************************/
 /*
-** 2007 June 22
+** 2007 May 6
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
@@ -83959,366 +97030,497 @@ SQLITE_PRIVATE void sqlite3Fts3PorterTokenizerModule(
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
-******************************************************************************
+*************************************************************************
+** $Id: icu.c,v 1.7 2007/12/13 21:54:11 drh Exp $
 **
-** This is part of an SQLite module implementing full-text search.
-** This particular file implements the generic tokenizer interface.
+** This file implements an integration between the ICU library 
+** ("International Components for Unicode", an open-source library 
+** for handling unicode data) and SQLite. The integration uses 
+** ICU to provide the following to SQLite:
+**
+**   * An implementation of the SQL regexp() function (and hence REGEXP
+**     operator) using the ICU uregex_XX() APIs.
+**
+**   * Implementations of the SQL scalar upper() and lower() functions
+**     for case mapping.
+**
+**   * Integration of ICU and SQLite collation seqences.
+**
+**   * An implementation of the LIKE operator that uses ICU to 
+**     provide case-independent matching.
+*/
+
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_ICU)
+
+/* Include ICU headers */
+#include 
+#include 
+#include 
+#include 
+
+
+#ifndef SQLITE_CORE
+  SQLITE_EXTENSION_INIT1
+#else
+#endif
+
+/*
+** Maximum length (in bytes) of the pattern in a LIKE or GLOB
+** operator.
+*/
+#ifndef SQLITE_MAX_LIKE_PATTERN_LENGTH
+# define SQLITE_MAX_LIKE_PATTERN_LENGTH 50000
+#endif
+
+/*
+** Version of sqlite3_free() that is always a function, never a macro.
+*/
+static void xFree(void *p){
+  sqlite3_free(p);
+}
+
+/*
+** Compare two UTF-8 strings for equality where the first string is
+** a "LIKE" expression. Return true (1) if they are the same and 
+** false (0) if they are different.
+*/
+static int icuLikeCompare(
+  const uint8_t *zPattern,   /* LIKE pattern */
+  const uint8_t *zString,    /* The UTF-8 string to compare against */
+  const UChar32 uEsc         /* The escape character */
+){
+  static const int MATCH_ONE = (UChar32)'_';
+  static const int MATCH_ALL = (UChar32)'%';
+
+  int iPattern = 0;       /* Current byte index in zPattern */
+  int iString = 0;        /* Current byte index in zString */
+
+  int prevEscape = 0;     /* True if the previous character was uEsc */
+
+  while( zPattern[iPattern]!=0 ){
+
+    /* Read (and consume) the next character from the input pattern. */
+    UChar32 uPattern;
+    U8_NEXT_UNSAFE(zPattern, iPattern, uPattern);
+    assert(uPattern!=0);
+
+    /* There are now 4 possibilities:
+    **
+    **     1. uPattern is an unescaped match-all character "%",
+    **     2. uPattern is an unescaped match-one character "_",
+    **     3. uPattern is an unescaped escape character, or
+    **     4. uPattern is to be handled as an ordinary character
+    */
+    if( !prevEscape && uPattern==MATCH_ALL ){
+      /* Case 1. */
+      uint8_t c;
+
+      /* Skip any MATCH_ALL or MATCH_ONE characters that follow a
+      ** MATCH_ALL. For each MATCH_ONE, skip one character in the 
+      ** test string.
+      */
+      while( (c=zPattern[iPattern]) == MATCH_ALL || c == MATCH_ONE ){
+        if( c==MATCH_ONE ){
+          if( zString[iString]==0 ) return 0;
+          U8_FWD_1_UNSAFE(zString, iString);
+        }
+        iPattern++;
+      }
+
+      if( zPattern[iPattern]==0 ) return 1;
+
+      while( zString[iString] ){
+        if( icuLikeCompare(&zPattern[iPattern], &zString[iString], uEsc) ){
+          return 1;
+        }
+        U8_FWD_1_UNSAFE(zString, iString);
+      }
+      return 0;
+
+    }else if( !prevEscape && uPattern==MATCH_ONE ){
+      /* Case 2. */
+      if( zString[iString]==0 ) return 0;
+      U8_FWD_1_UNSAFE(zString, iString);
+
+    }else if( !prevEscape && uPattern==uEsc){
+      /* Case 3. */
+      prevEscape = 1;
+
+    }else{
+      /* Case 4. */
+      UChar32 uString;
+      U8_NEXT_UNSAFE(zString, iString, uString);
+      uString = u_foldCase(uString, U_FOLD_CASE_DEFAULT);
+      uPattern = u_foldCase(uPattern, U_FOLD_CASE_DEFAULT);
+      if( uString!=uPattern ){
+        return 0;
+      }
+      prevEscape = 0;
+    }
+  }
+
+  return zString[iString]==0;
+}
+
+/*
+** Implementation of the like() SQL function.  This function implements
+** the build-in LIKE operator.  The first argument to the function is the
+** pattern and the second argument is the string.  So, the SQL statements:
+**
+**       A LIKE B
+**
+** is implemented as like(B, A). If there is an escape character E, 
+**
+**       A LIKE B ESCAPE E
+**
+** is mapped to like(B, A, E).
 */
+static void icuLikeFunc(
+  sqlite3_context *context, 
+  int argc, 
+  sqlite3_value **argv
+){
+  const unsigned char *zA = sqlite3_value_text(argv[0]);
+  const unsigned char *zB = sqlite3_value_text(argv[1]);
+  UChar32 uEsc = 0;
+
+  /* Limit the length of the LIKE or GLOB pattern to avoid problems
+  ** of deep recursion and N*N behavior in patternCompare().
+  */
+  if( sqlite3_value_bytes(argv[0])>SQLITE_MAX_LIKE_PATTERN_LENGTH ){
+    sqlite3_result_error(context, "LIKE or GLOB pattern too complex", -1);
+    return;
+  }
+
+
+  if( argc==3 ){
+    /* The escape character string must consist of a single UTF-8 character.
+    ** Otherwise, return an error.
+    */
+    int nE= sqlite3_value_bytes(argv[2]);
+    const unsigned char *zE = sqlite3_value_text(argv[2]);
+    int i = 0;
+    if( zE==0 ) return;
+    U8_NEXT(zE, i, nE, uEsc);
+    if( i!=nE){
+      sqlite3_result_error(context, 
+          "ESCAPE expression must be a single character", -1);
+      return;
+    }
+  }
+
+  if( zA && zB ){
+    sqlite3_result_int(context, icuLikeCompare(zA, zB, uEsc));
+  }
+}
 
 /*
-** The code in this file is only compiled if:
-**
-**     * The FTS3 module is being built as an extension
-**       (in which case SQLITE_CORE is not defined), or
+** This function is called when an ICU function called from within
+** the implementation of an SQL scalar function returns an error.
 **
-**     * The FTS3 module is being built into the core of
-**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
+** The scalar function context passed as the first argument is 
+** loaded with an error message based on the following two args.
 */
-#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
-
-#ifndef SQLITE_CORE
-  SQLITE_EXTENSION_INIT1
-#endif
+static void icuFunctionError(
+  sqlite3_context *pCtx,       /* SQLite scalar function context */
+  const char *zName,           /* Name of ICU function that failed */
+  UErrorCode e                 /* Error code returned by ICU function */
+){
+  char zBuf[128];
+  sqlite3_snprintf(128, zBuf, "ICU error: %s(): %s", zName, u_errorName(e));
+  zBuf[127] = '\0';
+  sqlite3_result_error(pCtx, zBuf, -1);
+}
 
+/*
+** Function to delete compiled regexp objects. Registered as
+** a destructor function with sqlite3_set_auxdata().
+*/
+static void icuRegexpDelete(void *p){
+  URegularExpression *pExpr = (URegularExpression *)p;
+  uregex_close(pExpr);
+}
 
 /*
-** Implementation of the SQL scalar function for accessing the underlying 
-** hash table. This function may be called as follows:
+** Implementation of SQLite REGEXP operator. This scalar function takes
+** two arguments. The first is a regular expression pattern to compile
+** the second is a string to match against that pattern. If either 
+** argument is an SQL NULL, then NULL Is returned. Otherwise, the result
+** is 1 if the string matches the pattern, or 0 otherwise.
 **
-**   SELECT ();
-**   SELECT (, );
+** SQLite maps the regexp() function to the regexp() operator such
+** that the following two are equivalent:
 **
-** where  is the name passed as the second argument
-** to the sqlite3Fts3InitHashTable() function (e.g. 'fts3_tokenizer').
+**     zString REGEXP zPattern
+**     regexp(zPattern, zString)
 **
-** If the  argument is specified, it must be a blob value
-** containing a pointer to be stored as the hash data corresponding
-** to the string . If  is not specified, then
-** the string  must already exist in the has table. Otherwise,
-** an error is returned.
+** Uses the following ICU regexp APIs:
 **
-** Whether or not the  argument is specified, the value returned
-** is a blob containing the pointer stored as the hash data corresponding
-** to string  (after the hash-table is updated, if applicable).
+**     uregex_open()
+**     uregex_matches()
+**     uregex_close()
 */
-static void scalarFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  fts3Hash *pHash;
-  void *pPtr = 0;
-  const unsigned char *zName;
-  int nName;
+static void icuRegexpFunc(sqlite3_context *p, int nArg, sqlite3_value **apArg){
+  UErrorCode status = U_ZERO_ERROR;
+  URegularExpression *pExpr;
+  UBool res;
+  const UChar *zString = sqlite3_value_text16(apArg[1]);
 
-  assert( argc==1 || argc==2 );
-
-  pHash = (fts3Hash *)sqlite3_user_data(context);
-
-  zName = sqlite3_value_text(argv[0]);
-  nName = sqlite3_value_bytes(argv[0])+1;
+  /* If the left hand side of the regexp operator is NULL, 
+  ** then the result is also NULL. 
+  */
+  if( !zString ){
+    return;
+  }
 
-  if( argc==2 ){
-    void *pOld;
-    int n = sqlite3_value_bytes(argv[1]);
-    if( n!=sizeof(pPtr) ){
-      sqlite3_result_error(context, "argument type mismatch", -1);
-      return;
-    }
-    pPtr = *(void **)sqlite3_value_blob(argv[1]);
-    pOld = sqlite3Fts3HashInsert(pHash, (void *)zName, nName, pPtr);
-    if( pOld==pPtr ){
-      sqlite3_result_error(context, "out of memory", -1);
+  pExpr = sqlite3_get_auxdata(p, 0);
+  if( !pExpr ){
+    const UChar *zPattern = sqlite3_value_text16(apArg[0]);
+    if( !zPattern ){
       return;
     }
-  }else{
-    pPtr = sqlite3Fts3HashFind(pHash, zName, nName);
-    if( !pPtr ){
-      char *zErr = sqlite3_mprintf("unknown tokenizer: %s", zName);
-      sqlite3_result_error(context, zErr, -1);
-      sqlite3_free(zErr);
+    pExpr = uregex_open(zPattern, -1, 0, 0, &status);
+
+    if( U_SUCCESS(status) ){
+      sqlite3_set_auxdata(p, 0, pExpr, icuRegexpDelete);
+    }else{
+      assert(!pExpr);
+      icuFunctionError(p, "uregex_open", status);
       return;
     }
   }
 
-  sqlite3_result_blob(context, (void *)&pPtr, sizeof(pPtr), SQLITE_TRANSIENT);
-}
+  /* Configure the text that the regular expression operates on. */
+  uregex_setText(pExpr, zString, -1, &status);
+  if( !U_SUCCESS(status) ){
+    icuFunctionError(p, "uregex_setText", status);
+    return;
+  }
 
-#ifdef SQLITE_TEST
+  /* Attempt the match */
+  res = uregex_matches(pExpr, 0, &status);
+  if( !U_SUCCESS(status) ){
+    icuFunctionError(p, "uregex_matches", status);
+    return;
+  }
 
+  /* Set the text that the regular expression operates on to a NULL
+  ** pointer. This is not really necessary, but it is tidier than 
+  ** leaving the regular expression object configured with an invalid
+  ** pointer after this function returns.
+  */
+  uregex_setText(pExpr, 0, 0, &status);
+
+  /* Return 1 or 0. */
+  sqlite3_result_int(p, res ? 1 : 0);
+}
 
 /*
-** Implementation of a special SQL scalar function for testing tokenizers 
-** designed to be used in concert with the Tcl testing framework. This
-** function must be called with two arguments:
+** Implementations of scalar functions for case mapping - upper() and 
+** lower(). Function upper() converts its input to upper-case (ABC).
+** Function lower() converts to lower-case (abc).
 **
-**   SELECT (, );
-**   SELECT (, );
+** ICU provides two types of case mapping, "general" case mapping and
+** "language specific". Refer to ICU documentation for the differences
+** between the two.
 **
-** where  is the name passed as the second argument
-** to the sqlite3Fts3InitHashTable() function (e.g. 'fts3_tokenizer')
-** concatenated with the string '_test' (e.g. 'fts3_tokenizer_test').
+** To utilise "general" case mapping, the upper() or lower() scalar 
+** functions are invoked with one argument:
 **
-** The return value is a string that may be interpreted as a Tcl
-** list. For each token in the , three elements are
-** added to the returned list. The first is the token position, the 
-** second is the token text (folded, stemmed, etc.) and the third is the
-** substring of  associated with the token. For example, 
-** using the built-in "simple" tokenizer:
+**     upper('ABC') -> 'abc'
+**     lower('abc') -> 'ABC'
 **
-**   SELECT fts_tokenizer_test('simple', 'I don't see how');
+** To access ICU "language specific" case mapping, upper() or lower()
+** should be invoked with two arguments. The second argument is the name
+** of the locale to use. Passing an empty string ("") or SQL NULL value
+** as the second argument is the same as invoking the 1 argument version
+** of upper() or lower().
 **
-** will return the string:
+**     lower('I', 'en_us') -> 'i'
+**     lower('I', 'tr_tr') -> 'ı' (small dotless i)
 **
-**   "{0 i I 1 dont don't 2 see see 3 how how}"
-**   
+** http://www.icu-project.org/userguide/posix.html#case_mappings
 */
-static void testFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  fts3Hash *pHash;
-  sqlite3_tokenizer_module *p;
-  sqlite3_tokenizer *pTokenizer = 0;
-  sqlite3_tokenizer_cursor *pCsr = 0;
-
-  const char *zErr = 0;
-
-  const char *zName;
-  int nName;
-  const char *zInput;
+static void icuCaseFunc16(sqlite3_context *p, int nArg, sqlite3_value **apArg){
+  const UChar *zInput;
+  UChar *zOutput;
   int nInput;
+  int nOutput;
 
-  const char *zArg = 0;
-
-  const char *zToken;
-  int nToken;
-  int iStart;
-  int iEnd;
-  int iPos;
-
-  Tcl_Obj *pRet;
-
-  assert( argc==2 || argc==3 );
-
-  nName = sqlite3_value_bytes(argv[0]);
-  zName = (const char *)sqlite3_value_text(argv[0]);
-  nInput = sqlite3_value_bytes(argv[argc-1]);
-  zInput = (const char *)sqlite3_value_text(argv[argc-1]);
+  UErrorCode status = U_ZERO_ERROR;
+  const char *zLocale = 0;
 
-  if( argc==3 ){
-    zArg = (const char *)sqlite3_value_text(argv[1]);
+  assert(nArg==1 || nArg==2);
+  if( nArg==2 ){
+    zLocale = (const char *)sqlite3_value_text(apArg[1]);
   }
 
-  pHash = (fts3Hash *)sqlite3_user_data(context);
-  p = (sqlite3_tokenizer_module *)sqlite3Fts3HashFind(pHash, zName, nName+1);
-
-  if( !p ){
-    char *zErr = sqlite3_mprintf("unknown tokenizer: %s", zName);
-    sqlite3_result_error(context, zErr, -1);
-    sqlite3_free(zErr);
+  zInput = sqlite3_value_text16(apArg[0]);
+  if( !zInput ){
     return;
   }
+  nInput = sqlite3_value_bytes16(apArg[0]);
 
-  pRet = Tcl_NewObj();
-  Tcl_IncrRefCount(pRet);
-
-  if( SQLITE_OK!=p->xCreate(zArg ? 1 : 0, &zArg, &pTokenizer) ){
-    zErr = "error in xCreate()";
-    goto finish;
-  }
-  pTokenizer->pModule = p;
-  if( SQLITE_OK!=p->xOpen(pTokenizer, zInput, nInput, &pCsr) ){
-    zErr = "error in xOpen()";
-    goto finish;
-  }
-  pCsr->pTokenizer = pTokenizer;
-
-  while( SQLITE_OK==p->xNext(pCsr, &zToken, &nToken, &iStart, &iEnd, &iPos) ){
-    Tcl_ListObjAppendElement(0, pRet, Tcl_NewIntObj(iPos));
-    Tcl_ListObjAppendElement(0, pRet, Tcl_NewStringObj(zToken, nToken));
-    zToken = &zInput[iStart];
-    nToken = iEnd-iStart;
-    Tcl_ListObjAppendElement(0, pRet, Tcl_NewStringObj(zToken, nToken));
-  }
-
-  if( SQLITE_OK!=p->xClose(pCsr) ){
-    zErr = "error in xClose()";
-    goto finish;
-  }
-  if( SQLITE_OK!=p->xDestroy(pTokenizer) ){
-    zErr = "error in xDestroy()";
-    goto finish;
+  nOutput = nInput * 2 + 2;
+  zOutput = sqlite3_malloc(nOutput);
+  if( !zOutput ){
+    return;
   }
 
-finish:
-  if( zErr ){
-    sqlite3_result_error(context, zErr, -1);
+  if( sqlite3_user_data(p) ){
+    u_strToUpper(zOutput, nOutput/2, zInput, nInput/2, zLocale, &status);
   }else{
-    sqlite3_result_text(context, Tcl_GetString(pRet), -1, SQLITE_TRANSIENT);
+    u_strToLower(zOutput, nOutput/2, zInput, nInput/2, zLocale, &status);
   }
-  Tcl_DecrRefCount(pRet);
-}
-
-static
-int registerTokenizer(
-  sqlite3 *db, 
-  char *zName, 
-  const sqlite3_tokenizer_module *p
-){
-  int rc;
-  sqlite3_stmt *pStmt;
-  const char zSql[] = "SELECT fts3_tokenizer(?, ?)";
 
-  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
-  if( rc!=SQLITE_OK ){
-    return rc;
+  if( !U_SUCCESS(status) ){
+    icuFunctionError(p, "u_strToLower()/u_strToUpper", status);
+    return;
   }
 
-  sqlite3_bind_text(pStmt, 1, zName, -1, SQLITE_STATIC);
-  sqlite3_bind_blob(pStmt, 2, &p, sizeof(p), SQLITE_STATIC);
-  sqlite3_step(pStmt);
+  sqlite3_result_text16(p, zOutput, -1, xFree);
+}
 
-  return sqlite3_finalize(pStmt);
+/*
+** Collation sequence destructor function. The pCtx argument points to
+** a UCollator structure previously allocated using ucol_open().
+*/
+static void icuCollationDel(void *pCtx){
+  UCollator *p = (UCollator *)pCtx;
+  ucol_close(p);
 }
 
-static
-int queryTokenizer(
-  sqlite3 *db, 
-  char *zName,  
-  const sqlite3_tokenizer_module **pp
+/*
+** Collation sequence comparison function. The pCtx argument points to
+** a UCollator structure previously allocated using ucol_open().
+*/
+static int icuCollationColl(
+  void *pCtx,
+  int nLeft,
+  const void *zLeft,
+  int nRight,
+  const void *zRight
 ){
-  int rc;
-  sqlite3_stmt *pStmt;
-  const char zSql[] = "SELECT fts3_tokenizer(?)";
-
-  *pp = 0;
-  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
-  if( rc!=SQLITE_OK ){
-    return rc;
-  }
-
-  sqlite3_bind_text(pStmt, 1, zName, -1, SQLITE_STATIC);
-  if( SQLITE_ROW==sqlite3_step(pStmt) ){
-    if( sqlite3_column_type(pStmt, 0)==SQLITE_BLOB ){
-      memcpy(pp, sqlite3_column_blob(pStmt, 0), sizeof(*pp));
-    }
-  }
-
-  return sqlite3_finalize(pStmt);
+  UCollationResult res;
+  UCollator *p = (UCollator *)pCtx;
+  res = ucol_strcoll(p, (UChar *)zLeft, nLeft/2, (UChar *)zRight, nRight/2);
+  switch( res ){
+    case UCOL_LESS:    return -1;
+    case UCOL_GREATER: return +1;
+    case UCOL_EQUAL:   return 0;
+  }
+  assert(!"Unexpected return value from ucol_strcoll()");
+  return 0;
 }
 
-SQLITE_PRIVATE void sqlite3Fts3SimpleTokenizerModule(sqlite3_tokenizer_module const**ppModule);
-
 /*
-** Implementation of the scalar function fts3_tokenizer_internal_test().
-** This function is used for testing only, it is not included in the
-** build unless SQLITE_TEST is defined.
-**
-** The purpose of this is to test that the fts3_tokenizer() function
-** can be used as designed by the C-code in the queryTokenizer and
-** registerTokenizer() functions above. These two functions are repeated
-** in the README.tokenizer file as an example, so it is important to
-** test them.
+** Implementation of the scalar function icu_load_collation().
 **
-** To run the tests, evaluate the fts3_tokenizer_internal_test() scalar
-** function with no arguments. An assert() will fail if a problem is
-** detected. i.e.:
+** This scalar function is used to add ICU collation based collation 
+** types to an SQLite database connection. It is intended to be called
+** as follows:
 **
-**     SELECT fts3_tokenizer_internal_test();
+**     SELECT icu_load_collation(, );
 **
+** Where  is a string containing an ICU locale identifier (i.e.
+** "en_AU", "tr_TR" etc.) and  is the name of the
+** collation sequence to create.
 */
-static void intTestFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
+static void icuLoadCollation(
+  sqlite3_context *p, 
+  int nArg, 
+  sqlite3_value **apArg
 ){
-  int rc;
-  const sqlite3_tokenizer_module *p1;
-  const sqlite3_tokenizer_module *p2;
-  sqlite3 *db = (sqlite3 *)sqlite3_user_data(context);
-
-  /* Test the query function */
-  sqlite3Fts3SimpleTokenizerModule(&p1);
-  rc = queryTokenizer(db, "simple", &p2);
-  assert( rc==SQLITE_OK );
-  assert( p1==p2 );
-  rc = queryTokenizer(db, "nosuchtokenizer", &p2);
-  assert( rc==SQLITE_ERROR );
-  assert( p2==0 );
-  assert( 0==strcmp(sqlite3_errmsg(db), "unknown tokenizer: nosuchtokenizer") );
+  sqlite3 *db = (sqlite3 *)sqlite3_user_data(p);
+  UErrorCode status = U_ZERO_ERROR;
+  const char *zLocale;      /* Locale identifier - (eg. "jp_JP") */
+  const char *zName;        /* SQL Collation sequence name (eg. "japanese") */
+  UCollator *pUCollator;    /* ICU library collation object */
+  int rc;                   /* Return code from sqlite3_create_collation_x() */
+
+  assert(nArg==2);
+  zLocale = (const char *)sqlite3_value_text(apArg[0]);
+  zName = (const char *)sqlite3_value_text(apArg[1]);
+
+  if( !zLocale || !zName ){
+    return;
+  }
 
-  /* Test the storage function */
-  rc = registerTokenizer(db, "nosuchtokenizer", p1);
-  assert( rc==SQLITE_OK );
-  rc = queryTokenizer(db, "nosuchtokenizer", &p2);
-  assert( rc==SQLITE_OK );
-  assert( p2==p1 );
+  pUCollator = ucol_open(zLocale, &status);
+  if( !U_SUCCESS(status) ){
+    icuFunctionError(p, "ucol_open", status);
+    return;
+  }
+  assert(p);
 
-  sqlite3_result_text(context, "ok", -1, SQLITE_STATIC);
+  rc = sqlite3_create_collation_v2(db, zName, SQLITE_UTF16, (void *)pUCollator, 
+      icuCollationColl, icuCollationDel
+  );
+  if( rc!=SQLITE_OK ){
+    ucol_close(pUCollator);
+    sqlite3_result_error(p, "Error registering collation function", -1);
+  }
 }
 
-#endif
-
 /*
-** Set up SQL objects in database db used to access the contents of
-** the hash table pointed to by argument pHash. The hash table must
-** been initialised to use string keys, and to take a private copy 
-** of the key when a value is inserted. i.e. by a call similar to:
-**
-**    sqlite3Fts3HashInit(pHash, FTS3_HASH_STRING, 1);
-**
-** This function adds a scalar function (see header comment above
-** scalarFunc() in this file for details) and, if ENABLE_TABLE is
-** defined at compilation time, a temporary virtual table (see header 
-** comment above struct HashTableVtab) to the database schema. Both 
-** provide read/write access to the contents of *pHash.
-**
-** The third argument to this function, zName, is used as the name
-** of both the scalar and, if created, the virtual table.
+** Register the ICU extension functions with database db.
 */
-SQLITE_PRIVATE int sqlite3Fts3InitHashTable(
-  sqlite3 *db, 
-  fts3Hash *pHash, 
-  const char *zName
-){
+SQLITE_PRIVATE int sqlite3IcuInit(sqlite3 *db){
+  struct IcuScalar {
+    const char *zName;                        /* Function name */
+    int nArg;                                 /* Number of arguments */
+    int enc;                                  /* Optimal text encoding */
+    void *pContext;                           /* sqlite3_user_data() context */
+    void (*xFunc)(sqlite3_context*,int,sqlite3_value**);
+  } scalars[] = {
+    {"regexp",-1, SQLITE_ANY,          0, icuRegexpFunc},
+
+    {"lower",  1, SQLITE_UTF16,        0, icuCaseFunc16},
+    {"lower",  2, SQLITE_UTF16,        0, icuCaseFunc16},
+    {"upper",  1, SQLITE_UTF16, (void*)1, icuCaseFunc16},
+    {"upper",  2, SQLITE_UTF16, (void*)1, icuCaseFunc16},
+
+    {"lower",  1, SQLITE_UTF8,         0, icuCaseFunc16},
+    {"lower",  2, SQLITE_UTF8,         0, icuCaseFunc16},
+    {"upper",  1, SQLITE_UTF8,  (void*)1, icuCaseFunc16},
+    {"upper",  2, SQLITE_UTF8,  (void*)1, icuCaseFunc16},
+
+    {"like",   2, SQLITE_UTF8,         0, icuLikeFunc},
+    {"like",   3, SQLITE_UTF8,         0, icuLikeFunc},
+
+    {"icu_load_collation",  2, SQLITE_UTF8, (void*)db, icuLoadCollation},
+  };
+
   int rc = SQLITE_OK;
-  void *p = (void *)pHash;
-  const int any = SQLITE_ANY;
-  char *zTest = 0;
-  char *zTest2 = 0;
+  int i;
 
-#ifdef SQLITE_TEST
-  void *pdb = (void *)db;
-  zTest = sqlite3_mprintf("%s_test", zName);
-  zTest2 = sqlite3_mprintf("%s_internal_test", zName);
-  if( !zTest || !zTest2 ){
-    rc = SQLITE_NOMEM;
+  for(i=0; rc==SQLITE_OK && i<(sizeof(scalars)/sizeof(struct IcuScalar)); i++){
+    struct IcuScalar *p = &scalars[i];
+    rc = sqlite3_create_function(
+        db, p->zName, p->nArg, p->enc, p->pContext, p->xFunc, 0, 0
+    );
   }
-#endif
-
-  if( rc!=SQLITE_OK
-   || (rc = sqlite3_create_function(db, zName, 1, any, p, scalarFunc, 0, 0))
-   || (rc = sqlite3_create_function(db, zName, 2, any, p, scalarFunc, 0, 0))
-#ifdef SQLITE_TEST
-   || (rc = sqlite3_create_function(db, zTest, 2, any, p, testFunc, 0, 0))
-   || (rc = sqlite3_create_function(db, zTest, 3, any, p, testFunc, 0, 0))
-   || (rc = sqlite3_create_function(db, zTest2, 0, any, pdb, intTestFunc, 0, 0))
-#endif
-  );
 
-  sqlite3_free(zTest);
-  sqlite3_free(zTest2);
   return rc;
 }
 
-#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
+#if !SQLITE_CORE
+SQLITE_API int sqlite3_extension_init(
+  sqlite3 *db, 
+  char **pzErrMsg,
+  const sqlite3_api_routines *pApi
+){
+  SQLITE_EXTENSION_INIT2(pApi)
+  return sqlite3IcuInit(db);
+}
+#endif
 
-/************** End of fts3_tokenizer.c **************************************/
-/************** Begin file fts3_tokenizer1.c *********************************/
+#endif
+
+/************** End of icu.c *************************************************/
+/************** Begin file fts3_icu.c ****************************************/
 /*
-** 2006 Oct 10
+** 2007 June 22
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
@@ -84327,94 +97529,77 @@ SQLITE_PRIVATE int sqlite3Fts3InitHashTable(
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
-******************************************************************************
-**
-** Implementation of the "simple" full-text-search tokenizer.
+*************************************************************************
+** This file implements a tokenizer for fts3 based on the ICU library.
+** 
+** $Id: fts3_icu.c,v 1.3 2008/09/01 18:34:20 danielk1977 Exp $
 */
 
-/*
-** The code in this file is only compiled if:
-**
-**     * The FTS3 module is being built as an extension
-**       (in which case SQLITE_CORE is not defined), or
-**
-**     * The FTS3 module is being built into the core of
-**       SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
-*/
 #if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
+#ifdef SQLITE_ENABLE_ICU
 
 
+#include 
+#include 
 
+typedef struct IcuTokenizer IcuTokenizer;
+typedef struct IcuCursor IcuCursor;
 
-typedef struct simple_tokenizer {
+struct IcuTokenizer {
   sqlite3_tokenizer base;
-  char delim[128];             /* flag ASCII delimiters */
-} simple_tokenizer;
+  char *zLocale;
+};
 
-typedef struct simple_tokenizer_cursor {
+struct IcuCursor {
   sqlite3_tokenizer_cursor base;
-  const char *pInput;          /* input we are tokenizing */
-  int nBytes;                  /* size of the input */
-  int iOffset;                 /* current position in pInput */
-  int iToken;                  /* index of next token to be returned */
-  char *pToken;                /* storage for current token */
-  int nTokenAllocated;         /* space allocated to zToken buffer */
-} simple_tokenizer_cursor;
 
+  UBreakIterator *pIter;      /* ICU break-iterator object */
+  int nChar;                  /* Number of UChar elements in pInput */
+  UChar *aChar;               /* Copy of input using utf-16 encoding */
+  int *aOffset;               /* Offsets of each character in utf-8 input */
 
-/* Forward declaration */
-static const sqlite3_tokenizer_module simpleTokenizerModule;
+  int nBuffer;
+  char *zBuffer;
 
-static int simpleDelim(simple_tokenizer *t, unsigned char c){
-  return c<0x80 && t->delim[c];
-}
+  int iToken;
+};
 
 /*
 ** Create a new tokenizer instance.
 */
-static int simpleCreate(
-  int argc, const char * const *argv,
-  sqlite3_tokenizer **ppTokenizer
+static int icuCreate(
+  int argc,                            /* Number of entries in argv[] */
+  const char * const *argv,            /* Tokenizer creation arguments */
+  sqlite3_tokenizer **ppTokenizer      /* OUT: Created tokenizer */
 ){
-  simple_tokenizer *t;
+  IcuTokenizer *p;
+  int n = 0;
 
-  t = (simple_tokenizer *) sqlite3_malloc(sizeof(*t));
-  if( t==NULL ) return SQLITE_NOMEM;
-  memset(t, 0, sizeof(*t));
+  if( argc>0 ){
+    n = strlen(argv[0])+1;
+  }
+  p = (IcuTokenizer *)sqlite3_malloc(sizeof(IcuTokenizer)+n);
+  if( !p ){
+    return SQLITE_NOMEM;
+  }
+  memset(p, 0, sizeof(IcuTokenizer));
 
-  /* TODO(shess) Delimiters need to remain the same from run to run,
-  ** else we need to reindex.  One solution would be a meta-table to
-  ** track such information in the database, then we'd only want this
-  ** information on the initial create.
-  */
-  if( argc>1 ){
-    int i, n = strlen(argv[1]);
-    for(i=0; i=0x80 ){
-        sqlite3_free(t);
-        return SQLITE_ERROR;
-      }
-      t->delim[ch] = 1;
-    }
-  } else {
-    /* Mark non-alphanumeric ASCII characters as delimiters */
-    int i;
-    for(i=1; i<0x80; i++){
-      t->delim[i] = !isalnum(i);
-    }
+  if( n ){
+    p->zLocale = (char *)&p[1];
+    memcpy(p->zLocale, argv[0], n);
   }
 
-  *ppTokenizer = &t->base;
+  *ppTokenizer = (sqlite3_tokenizer *)p;
+
   return SQLITE_OK;
 }
 
 /*
 ** Destroy a tokenizer
 */
-static int simpleDestroy(sqlite3_tokenizer *pTokenizer){
-  sqlite3_free(pTokenizer);
+static int icuDestroy(sqlite3_tokenizer *pTokenizer){
+  IcuTokenizer *p = (IcuTokenizer *)pTokenizer;
+  sqlite3_free(p);
   return SQLITE_OK;
 }
 
@@ -84424,49 +97609,87 @@ static int simpleDestroy(sqlite3_tokenizer *pTokenizer){
 ** used to incrementally tokenize this string is returned in 
 ** *ppCursor.
 */
-static int simpleOpen(
+static int icuOpen(
   sqlite3_tokenizer *pTokenizer,         /* The tokenizer */
-  const char *pInput, int nBytes,        /* String to be tokenized */
+  const char *zInput,                    /* Input string */
+  int nInput,                            /* Length of zInput in bytes */
   sqlite3_tokenizer_cursor **ppCursor    /* OUT: Tokenization cursor */
 ){
-  simple_tokenizer_cursor *c;
+  IcuTokenizer *p = (IcuTokenizer *)pTokenizer;
+  IcuCursor *pCsr;
 
-  c = (simple_tokenizer_cursor *) sqlite3_malloc(sizeof(*c));
-  if( c==NULL ) return SQLITE_NOMEM;
+  const int32_t opt = U_FOLD_CASE_DEFAULT;
+  UErrorCode status = U_ZERO_ERROR;
+  int nChar;
 
-  c->pInput = pInput;
-  if( pInput==0 ){
-    c->nBytes = 0;
-  }else if( nBytes<0 ){
-    c->nBytes = (int)strlen(pInput);
-  }else{
-    c->nBytes = nBytes;
+  UChar32 c;
+  int iInput = 0;
+  int iOut = 0;
+
+  *ppCursor = 0;
+
+  if( nInput<0 ){
+    nInput = strlen(zInput);
   }
-  c->iOffset = 0;                 /* start tokenizing at the beginning */
-  c->iToken = 0;
-  c->pToken = NULL;               /* no space allocated, yet. */
-  c->nTokenAllocated = 0;
+  nChar = nInput+1;
+  pCsr = (IcuCursor *)sqlite3_malloc(
+      sizeof(IcuCursor) +                /* IcuCursor */
+      nChar * sizeof(UChar) +            /* IcuCursor.aChar[] */
+      (nChar+1) * sizeof(int)            /* IcuCursor.aOffset[] */
+  );
+  if( !pCsr ){
+    return SQLITE_NOMEM;
+  }
+  memset(pCsr, 0, sizeof(IcuCursor));
+  pCsr->aChar = (UChar *)&pCsr[1];
+  pCsr->aOffset = (int *)&pCsr->aChar[nChar];
+
+  pCsr->aOffset[iOut] = iInput;
+  U8_NEXT(zInput, iInput, nInput, c); 
+  while( c>0 ){
+    int isError = 0;
+    c = u_foldCase(c, opt);
+    U16_APPEND(pCsr->aChar, iOut, nChar, c, isError);
+    if( isError ){
+      sqlite3_free(pCsr);
+      return SQLITE_ERROR;
+    }
+    pCsr->aOffset[iOut] = iInput;
 
-  *ppCursor = &c->base;
+    if( iInputpIter = ubrk_open(UBRK_WORD, p->zLocale, pCsr->aChar, iOut, &status);
+  if( !U_SUCCESS(status) ){
+    sqlite3_free(pCsr);
+    return SQLITE_ERROR;
+  }
+  pCsr->nChar = iOut;
+
+  ubrk_first(pCsr->pIter);
+  *ppCursor = (sqlite3_tokenizer_cursor *)pCsr;
   return SQLITE_OK;
 }
 
 /*
-** Close a tokenization cursor previously opened by a call to
-** simpleOpen() above.
+** Close a tokenization cursor previously opened by a call to icuOpen().
 */
-static int simpleClose(sqlite3_tokenizer_cursor *pCursor){
-  simple_tokenizer_cursor *c = (simple_tokenizer_cursor *) pCursor;
-  sqlite3_free(c->pToken);
-  sqlite3_free(c);
+static int icuClose(sqlite3_tokenizer_cursor *pCursor){
+  IcuCursor *pCsr = (IcuCursor *)pCursor;
+  ubrk_close(pCsr->pIter);
+  sqlite3_free(pCsr->zBuffer);
+  sqlite3_free(pCsr);
   return SQLITE_OK;
 }
 
 /*
-** Extract the next token from a tokenization cursor.  The cursor must
-** have been opened by a prior call to simpleOpen().
+** Extract the next token from a tokenization cursor.
 */
-static int simpleNext(
+static int icuNext(
   sqlite3_tokenizer_cursor *pCursor,  /* Cursor returned by simpleOpen */
   const char **ppToken,               /* OUT: *ppToken is the token text */
   int *pnBytes,                       /* OUT: Number of bytes in token */
@@ -84474,72 +97697,82 @@ static int simpleNext(
   int *piEndOffset,                   /* OUT: Ending offset of token */
   int *piPosition                     /* OUT: Position integer of token */
 ){
-  simple_tokenizer_cursor *c = (simple_tokenizer_cursor *) pCursor;
-  simple_tokenizer *t = (simple_tokenizer *) pCursor->pTokenizer;
-  unsigned char *p = (unsigned char *)c->pInput;
+  IcuCursor *pCsr = (IcuCursor *)pCursor;
 
-  while( c->iOffsetnBytes ){
-    int iStartOffset;
+  int iStart = 0;
+  int iEnd = 0;
+  int nByte = 0;
 
-    /* Scan past delimiter characters */
-    while( c->iOffsetnBytes && simpleDelim(t, p[c->iOffset]) ){
-      c->iOffset++;
-    }
+  while( iStart==iEnd ){
+    UChar32 c;
 
-    /* Count non-delimiter characters. */
-    iStartOffset = c->iOffset;
-    while( c->iOffsetnBytes && !simpleDelim(t, p[c->iOffset]) ){
-      c->iOffset++;
+    iStart = ubrk_current(pCsr->pIter);
+    iEnd = ubrk_next(pCsr->pIter);
+    if( iEnd==UBRK_DONE ){
+      return SQLITE_DONE;
     }
 
-    if( c->iOffset>iStartOffset ){
-      int i, n = c->iOffset-iStartOffset;
-      if( n>c->nTokenAllocated ){
-        c->nTokenAllocated = n+20;
-        c->pToken = sqlite3_realloc(c->pToken, c->nTokenAllocated);
-        if( c->pToken==NULL ) return SQLITE_NOMEM;
-      }
-      for(i=0; ipToken[i] = ch<0x80 ? tolower(ch) : ch;
+    while( iStartaChar, iWhite, pCsr->nChar, c);
+      if( u_isspace(c) ){
+        iStart = iWhite;
+      }else{
+        break;
       }
-      *ppToken = c->pToken;
-      *pnBytes = n;
-      *piStartOffset = iStartOffset;
-      *piEndOffset = c->iOffset;
-      *piPosition = c->iToken++;
-
-      return SQLITE_OK;
     }
+    assert(iStart<=iEnd);
   }
-  return SQLITE_DONE;
+
+  do {
+    UErrorCode status = U_ZERO_ERROR;
+    if( nByte ){
+      char *zNew = sqlite3_realloc(pCsr->zBuffer, nByte);
+      if( !zNew ){
+        return SQLITE_NOMEM;
+      }
+      pCsr->zBuffer = zNew;
+      pCsr->nBuffer = nByte;
+    }
+
+    u_strToUTF8(
+        pCsr->zBuffer, pCsr->nBuffer, &nByte,    /* Output vars */
+        &pCsr->aChar[iStart], iEnd-iStart,       /* Input vars */
+        &status                                  /* Output success/failure */
+    );
+  } while( nByte>pCsr->nBuffer );
+
+  *ppToken = pCsr->zBuffer;
+  *pnBytes = nByte;
+  *piStartOffset = pCsr->aOffset[iStart];
+  *piEndOffset = pCsr->aOffset[iEnd];
+  *piPosition = pCsr->iToken++;
+
+  return SQLITE_OK;
 }
 
 /*
 ** The set of routines that implement the simple tokenizer
 */
-static const sqlite3_tokenizer_module simpleTokenizerModule = {
-  0,
-  simpleCreate,
-  simpleDestroy,
-  simpleOpen,
-  simpleClose,
-  simpleNext,
+static const sqlite3_tokenizer_module icuTokenizerModule = {
+  0,                           /* iVersion */
+  icuCreate,                   /* xCreate  */
+  icuDestroy,                  /* xCreate  */
+  icuOpen,                     /* xOpen    */
+  icuClose,                    /* xClose   */
+  icuNext,                     /* xNext    */
 };
 
 /*
-** Allocate a new simple tokenizer.  Return a pointer to the new
-** tokenizer in *ppModule
+** Set *ppModule to point at the implementation of the ICU tokenizer.
 */
-SQLITE_PRIVATE void sqlite3Fts3SimpleTokenizerModule(
+SQLITE_PRIVATE void sqlite3Fts3IcuTokenizerModule(
   sqlite3_tokenizer_module const**ppModule
 ){
-  *ppModule = &simpleTokenizerModule;
+  *ppModule = &icuTokenizerModule;
 }
 
+#endif /* defined(SQLITE_ENABLE_ICU) */
 #endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
 
-/************** End of fts3_tokenizer1.c *************************************/
+/************** End of fts3_icu.c ********************************************/