4 ** The author disclaims copyright to this source code. In place of
5 ** a legal notice, here is a blessing:
7 ** May you do good and not evil.
8 ** May you find forgiveness for yourself and forgive others.
9 ** May you share freely, never taking more than you give.
11 *************************************************************************
12 ** This header file defines the interface that the SQLite library
13 ** presents to client programs. If a C-function, structure, datatype,
14 ** or constant definition does not appear in this file, then it is
15 ** not a published API of SQLite, is subject to change without
16 ** notice, and should not be referenced by programs that use SQLite.
18 ** Some of the definitions that are in this file are marked as
19 ** "experimental". Experimental interfaces are normally new
20 ** features recently added to SQLite. We do not anticipate changes
21 ** to experimental interfaces but reserve to make minor changes if
22 ** experience from use "in the wild" suggest such changes are prudent.
24 ** The official C-language API documentation for SQLite is derived
25 ** from comments in this file. This file is the authoritative source
26 ** on how SQLite interfaces are suppose to operate.
28 ** The name of this file under configuration management is "sqlite.h.in".
29 ** The makefile makes some minor changes to this file (such as inserting
30 ** the version number) and changes its name to "sqlite3.h" as
31 ** part of the build process.
33 ** @(#) $Id: sqlite.h.in,v 1.387 2008/08/05 17:53:23 drh Exp $
37 #include <stdarg.h> /* Needed for the definition of va_list */
40 ** Make sure we can call this stuff from C++.
48 ** Add the ability to override 'extern'
51 # define SQLITE_EXTERN extern
55 ** Ensure these symbols were not defined by some previous header file.
58 # undef SQLITE_VERSION
60 #ifdef SQLITE_VERSION_NUMBER
61 # undef SQLITE_VERSION_NUMBER
65 ** CAPI3REF: Compile-Time Library Version Numbers {H10010} <S60100>
67 ** The SQLITE_VERSION and SQLITE_VERSION_NUMBER #defines in
68 ** the sqlite3.h file specify the version of SQLite with which
69 ** that header file is associated.
71 ** The "version" of SQLite is a string of the form "X.Y.Z".
72 ** The phrase "alpha" or "beta" might be appended after the Z.
73 ** The X value is major version number always 3 in SQLite3.
74 ** The X value only changes when backwards compatibility is
75 ** broken and we intend to never break backwards compatibility.
76 ** The Y value is the minor version number and only changes when
77 ** there are major feature enhancements that are forwards compatible
78 ** but not backwards compatible.
79 ** The Z value is the release number and is incremented with
80 ** each release but resets back to 0 whenever Y is incremented.
82 ** See also: [sqlite3_libversion()] and [sqlite3_libversion_number()].
86 ** {H10011} The SQLITE_VERSION #define in the sqlite3.h header file shall
87 ** evaluate to a string literal that is the SQLite version
88 ** with which the header file is associated.
90 ** {H10014} The SQLITE_VERSION_NUMBER #define shall resolve to an integer
91 ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z
92 ** are the major version, minor version, and release number.
94 #define SQLITE_VERSION "3.6.1"
95 #define SQLITE_VERSION_NUMBER 3006001
98 ** CAPI3REF: Run-Time Library Version Numbers {H10020} <S60100>
99 ** KEYWORDS: sqlite3_version
101 ** These features provide the same information as the [SQLITE_VERSION]
102 ** and [SQLITE_VERSION_NUMBER] #defines in the header, but are associated
103 ** with the library instead of the header file. Cautious programmers might
104 ** include a check in their application to verify that
105 ** sqlite3_libversion_number() always returns the value
106 ** [SQLITE_VERSION_NUMBER].
108 ** The sqlite3_libversion() function returns the same information as is
109 ** in the sqlite3_version[] string constant. The function is provided
110 ** for use in DLLs since DLL users usually do not have direct access to string
111 ** constants within the DLL.
115 ** {H10021} The [sqlite3_libversion_number()] interface shall return
116 ** an integer equal to [SQLITE_VERSION_NUMBER].
118 ** {H10022} The [sqlite3_version] string constant shall contain
119 ** the text of the [SQLITE_VERSION] string.
121 ** {H10023} The [sqlite3_libversion()] function shall return
122 ** a pointer to the [sqlite3_version] string constant.
124 SQLITE_EXTERN const char sqlite3_version[];
125 const char *sqlite3_libversion(void);
126 int sqlite3_libversion_number(void);
129 ** CAPI3REF: Test To See If The Library Is Threadsafe {H10100} <S60100>
131 ** SQLite can be compiled with or without mutexes. When
132 ** the [SQLITE_THREADSAFE] C preprocessor macro is true, mutexes
133 ** are enabled and SQLite is threadsafe. When that macro is false,
134 ** the mutexes are omitted. Without the mutexes, it is not safe
135 ** to use SQLite concurrently from more than one thread.
137 ** Enabling mutexes incurs a measurable performance penalty.
138 ** So if speed is of utmost importance, it makes sense to disable
139 ** the mutexes. But for maximum safety, mutexes should be enabled.
140 ** The default behavior is for mutexes to be enabled.
142 ** This interface can be used by a program to make sure that the
143 ** version of SQLite that it is linking against was compiled with
144 ** the desired setting of the [SQLITE_THREADSAFE] macro.
146 ** This interface only reports on the compile-time mutex setting
147 ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
148 ** SQLITE_THREADSAFE=1 then mutexes are enabled by default but
149 ** can be fully or partially disabled using a call to [sqlite3_config()]
150 ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
151 ** or [SQLITE_CONFIG_MUTEX]. The return value of this function shows
152 ** only the default compile-time setting, not any run-time changes
157 ** {H10101} The [sqlite3_threadsafe()] function shall return nonzero if
158 ** SQLite was compiled with the its mutexes enabled by default
159 ** or zero if SQLite was compiled such that mutexes are
160 ** permanently disabled.
162 ** {H10102} The value returned by the [sqlite3_threadsafe()] function
163 ** shall not change when mutex setting are modified at
164 ** runtime using the [sqlite3_config()] interface and
165 ** especially the [SQLITE_CONFIG_SINGLETHREAD],
166 ** [SQLITE_CONFIG_MULTITHREAD], [SQLITE_CONFIG_SERIALIZED],
167 ** and [SQLITE_CONFIG_MUTEX] verbs.
169 int sqlite3_threadsafe(void);
172 ** CAPI3REF: Database Connection Handle {H12000} <S40200>
173 ** KEYWORDS: {database connection} {database connections}
175 ** Each open SQLite database is represented by a pointer to an instance of
176 ** the opaque structure named "sqlite3". It is useful to think of an sqlite3
177 ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
178 ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
179 ** is its destructor. There are many other interfaces (such as
180 ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
181 ** [sqlite3_busy_timeout()] to name but three) that are methods on an
184 typedef struct sqlite3 sqlite3;
187 ** CAPI3REF: 64-Bit Integer Types {H10200} <S10110>
188 ** KEYWORDS: sqlite_int64 sqlite_uint64
190 ** Because there is no cross-platform way to specify 64-bit integer types
191 ** SQLite includes typedefs for 64-bit signed and unsigned integers.
193 ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
194 ** The sqlite_int64 and sqlite_uint64 types are supported for backwards
195 ** compatibility only.
199 ** {H10201} The [sqlite_int64] and [sqlite3_int64] type shall specify
200 ** a 64-bit signed integer.
202 ** {H10202} The [sqlite_uint64] and [sqlite3_uint64] type shall specify
203 ** a 64-bit unsigned integer.
205 #ifdef SQLITE_INT64_TYPE
206 typedef SQLITE_INT64_TYPE sqlite_int64;
207 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
208 #elif defined(_MSC_VER) || defined(__BORLANDC__)
209 typedef __int64 sqlite_int64;
210 typedef unsigned __int64 sqlite_uint64;
212 typedef long long int sqlite_int64;
213 typedef unsigned long long int sqlite_uint64;
215 typedef sqlite_int64 sqlite3_int64;
216 typedef sqlite_uint64 sqlite3_uint64;
219 ** If compiling for a processor that lacks floating point support,
220 ** substitute integer for floating-point.
222 #ifdef SQLITE_OMIT_FLOATING_POINT
223 # define double sqlite3_int64
227 ** CAPI3REF: Closing A Database Connection {H12010} <S30100><S40200>
229 ** This routine is the destructor for the [sqlite3] object.
231 ** Applications should [sqlite3_finalize | finalize] all [prepared statements]
232 ** and [sqlite3_blob_close | close] all [BLOB handles] associated with
233 ** the [sqlite3] object prior to attempting to close the object.
234 ** The [sqlite3_next_stmt()] interface can be used to locate all
235 ** [prepared statements] associated with a [database connection] if desired.
236 ** Typical code might look like this:
239 ** sqlite3_stmt *pStmt;
240 ** while( (pStmt = sqlite3_next_stmt(db, 0))!=0 ){
241 ** sqlite3_finalize(pStmt);
243 ** </pre></blockquote>
245 ** If [sqlite3_close()] is invoked while a transaction is open,
246 ** the transaction is automatically rolled back.
250 ** {H12011} A successful call to [sqlite3_close(C)] shall destroy the
251 ** [database connection] object C.
253 ** {H12012} A successful call to [sqlite3_close(C)] shall return SQLITE_OK.
255 ** {H12013} A successful call to [sqlite3_close(C)] shall release all
256 ** memory and system resources associated with [database connection]
259 ** {H12014} A call to [sqlite3_close(C)] on a [database connection] C that
260 ** has one or more open [prepared statements] shall fail with
261 ** an [SQLITE_BUSY] error code.
263 ** {H12015} A call to [sqlite3_close(C)] where C is a NULL pointer shall
266 ** {H12019} When [sqlite3_close(C)] is invoked on a [database connection] C
267 ** that has a pending transaction, the transaction shall be
272 ** {A12016} The C parameter to [sqlite3_close(C)] must be either a NULL
273 ** pointer or an [sqlite3] object pointer obtained
274 ** from [sqlite3_open()], [sqlite3_open16()], or
275 ** [sqlite3_open_v2()], and not previously closed.
277 int sqlite3_close(sqlite3 *);
280 ** The type for a callback function.
281 ** This is legacy and deprecated. It is included for historical
282 ** compatibility and is not documented.
284 typedef int (*sqlite3_callback)(void*,int,char**, char**);
287 ** CAPI3REF: One-Step Query Execution Interface {H12100} <S10000>
289 ** The sqlite3_exec() interface is a convenient way of running one or more
290 ** SQL statements without having to write a lot of C code. The UTF-8 encoded
291 ** SQL statements are passed in as the second parameter to sqlite3_exec().
292 ** The statements are evaluated one by one until either an error or
293 ** an interrupt is encountered, or until they are all done. The 3rd parameter
294 ** is an optional callback that is invoked once for each row of any query
295 ** results produced by the SQL statements. The 5th parameter tells where
296 ** to write any error messages.
298 ** The error message passed back through the 5th parameter is held
299 ** in memory obtained from [sqlite3_malloc()]. To avoid a memory leak,
300 ** the calling application should call [sqlite3_free()] on any error
301 ** message returned through the 5th parameter when it has finished using
302 ** the error message.
304 ** If the SQL statement in the 2nd parameter is NULL or an empty string
305 ** or a string containing only whitespace and comments, then no SQL
306 ** statements are evaluated and the database is not changed.
308 ** The sqlite3_exec() interface is implemented in terms of
309 ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
310 ** The sqlite3_exec() routine does nothing to the database that cannot be done
311 ** by [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
315 ** {H12101} A successful invocation of [sqlite3_exec(D,S,C,A,E)]
316 ** shall sequentially evaluate all of the UTF-8 encoded,
317 ** semicolon-separated SQL statements in the zero-terminated
318 ** string S within the context of the [database connection] D.
320 ** {H12102} If the S parameter to [sqlite3_exec(D,S,C,A,E)] is NULL then
321 ** the actions of the interface shall be the same as if the
322 ** S parameter were an empty string.
324 ** {H12104} The return value of [sqlite3_exec()] shall be [SQLITE_OK] if all
325 ** SQL statements run successfully and to completion.
327 ** {H12105} The return value of [sqlite3_exec()] shall be an appropriate
328 ** non-zero [error code] if any SQL statement fails.
330 ** {H12107} If one or more of the SQL statements handed to [sqlite3_exec()]
331 ** return results and the 3rd parameter is not NULL, then
332 ** the callback function specified by the 3rd parameter shall be
333 ** invoked once for each row of result.
335 ** {H12110} If the callback returns a non-zero value then [sqlite3_exec()]
336 ** shall abort the SQL statement it is currently evaluating,
337 ** skip all subsequent SQL statements, and return [SQLITE_ABORT].
339 ** {H12113} The [sqlite3_exec()] routine shall pass its 4th parameter through
340 ** as the 1st parameter of the callback.
342 ** {H12116} The [sqlite3_exec()] routine shall set the 2nd parameter of its
343 ** callback to be the number of columns in the current row of
346 ** {H12119} The [sqlite3_exec()] routine shall set the 3rd parameter of its
347 ** callback to be an array of pointers to strings holding the
348 ** values for each column in the current result set row as
349 ** obtained from [sqlite3_column_text()].
351 ** {H12122} The [sqlite3_exec()] routine shall set the 4th parameter of its
352 ** callback to be an array of pointers to strings holding the
353 ** names of result columns as obtained from [sqlite3_column_name()].
355 ** {H12125} If the 3rd parameter to [sqlite3_exec()] is NULL then
356 ** [sqlite3_exec()] shall silently discard query results.
358 ** {H12131} If an error occurs while parsing or evaluating any of the SQL
359 ** statements in the S parameter of [sqlite3_exec(D,S,C,A,E)] and if
360 ** the E parameter is not NULL, then [sqlite3_exec()] shall store
361 ** in *E an appropriate error message written into memory obtained
362 ** from [sqlite3_malloc()].
364 ** {H12134} The [sqlite3_exec(D,S,C,A,E)] routine shall set the value of
365 ** *E to NULL if E is not NULL and there are no errors.
367 ** {H12137} The [sqlite3_exec(D,S,C,A,E)] function shall set the [error code]
368 ** and message accessible via [sqlite3_errcode()],
369 ** [sqlite3_errmsg()], and [sqlite3_errmsg16()].
371 ** {H12138} If the S parameter to [sqlite3_exec(D,S,C,A,E)] is NULL or an
372 ** empty string or contains nothing other than whitespace, comments,
373 ** and/or semicolons, then results of [sqlite3_errcode()],
374 ** [sqlite3_errmsg()], and [sqlite3_errmsg16()]
375 ** shall reset to indicate no errors.
379 ** {A12141} The first parameter to [sqlite3_exec()] must be an valid and open
380 ** [database connection].
382 ** {A12142} The database connection must not be closed while
383 ** [sqlite3_exec()] is running.
385 ** {A12143} The calling function should use [sqlite3_free()] to free
386 ** the memory that *errmsg is left pointing at once the error
387 ** message is no longer needed.
389 ** {A12145} The SQL statement text in the 2nd parameter to [sqlite3_exec()]
390 ** must remain unchanged while [sqlite3_exec()] is running.
393 sqlite3*, /* An open database */
394 const char *sql, /* SQL to be evaluated */
395 int (*callback)(void*,int,char**,char**), /* Callback function */
396 void *, /* 1st argument to callback */
397 char **errmsg /* Error msg written here */
401 ** CAPI3REF: Result Codes {H10210} <S10700>
402 ** KEYWORDS: SQLITE_OK {error code} {error codes}
403 ** KEYWORDS: {result code} {result codes}
405 ** Many SQLite functions return an integer result code from the set shown
406 ** here in order to indicates success or failure.
408 ** New error codes may be added in future versions of SQLite.
410 ** See also: [SQLITE_IOERR_READ | extended result codes]
412 #define SQLITE_OK 0 /* Successful result */
413 /* beginning-of-error-codes */
414 #define SQLITE_ERROR 1 /* SQL error or missing database */
415 #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
416 #define SQLITE_PERM 3 /* Access permission denied */
417 #define SQLITE_ABORT 4 /* Callback routine requested an abort */
418 #define SQLITE_BUSY 5 /* The database file is locked */
419 #define SQLITE_LOCKED 6 /* A table in the database is locked */
420 #define SQLITE_NOMEM 7 /* A malloc() failed */
421 #define SQLITE_READONLY 8 /* Attempt to write a readonly database */
422 #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
423 #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
424 #define SQLITE_CORRUPT 11 /* The database disk image is malformed */
425 #define SQLITE_NOTFOUND 12 /* NOT USED. Table or record not found */
426 #define SQLITE_FULL 13 /* Insertion failed because database is full */
427 #define SQLITE_CANTOPEN 14 /* Unable to open the database file */
428 #define SQLITE_PROTOCOL 15 /* NOT USED. Database lock protocol error */
429 #define SQLITE_EMPTY 16 /* Database is empty */
430 #define SQLITE_SCHEMA 17 /* The database schema changed */
431 #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
432 #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
433 #define SQLITE_MISMATCH 20 /* Data type mismatch */
434 #define SQLITE_MISUSE 21 /* Library used incorrectly */
435 #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
436 #define SQLITE_AUTH 23 /* Authorization denied */
437 #define SQLITE_FORMAT 24 /* Auxiliary database format error */
438 #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
439 #define SQLITE_NOTADB 26 /* File opened that is not a database file */
440 #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
441 #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
442 /* end-of-error-codes */
445 ** CAPI3REF: Extended Result Codes {H10220} <S10700>
446 ** KEYWORDS: {extended error code} {extended error codes}
447 ** KEYWORDS: {extended result code} {extended result codes}
449 ** In its default configuration, SQLite API routines return one of 26 integer
450 ** [SQLITE_OK | result codes]. However, experience has shown that many of
451 ** these result codes are too coarse-grained. They do not provide as
452 ** much information about problems as programmers might like. In an effort to
453 ** address this, newer versions of SQLite (version 3.3.8 and later) include
454 ** support for additional result codes that provide more detailed information
455 ** about errors. The extended result codes are enabled or disabled
456 ** on a per database connection basis using the
457 ** [sqlite3_extended_result_codes()] API.
459 ** Some of the available extended result codes are listed here.
460 ** One may expect the number of extended result codes will be expand
461 ** over time. Software that uses extended result codes should expect
462 ** to see new result codes in future releases of SQLite.
464 ** The SQLITE_OK result code will never be extended. It will always
469 ** {H10223} The symbolic name for an extended result code shall contains
470 ** a related primary result code as a prefix.
472 ** {H10224} Primary result code names shall contain a single "_" character.
474 ** {H10225} Extended result code names shall contain two or more "_" characters.
476 ** {H10226} The numeric value of an extended result code shall contain the
477 ** numeric value of its corresponding primary result code in
478 ** its least significant 8 bits.
480 #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
481 #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
482 #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
483 #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
484 #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
485 #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
486 #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
487 #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
488 #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
489 #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
490 #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
491 #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
492 #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
493 #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
496 ** CAPI3REF: Flags For File Open Operations {H10230} <H11120> <H12700>
498 ** These bit values are intended for use in the
499 ** 3rd parameter to the [sqlite3_open_v2()] interface and
500 ** in the 4th parameter to the xOpen method of the
501 ** [sqlite3_vfs] object.
503 #define SQLITE_OPEN_READONLY 0x00000001
504 #define SQLITE_OPEN_READWRITE 0x00000002
505 #define SQLITE_OPEN_CREATE 0x00000004
506 #define SQLITE_OPEN_DELETEONCLOSE 0x00000008
507 #define SQLITE_OPEN_EXCLUSIVE 0x00000010
508 #define SQLITE_OPEN_MAIN_DB 0x00000100
509 #define SQLITE_OPEN_TEMP_DB 0x00000200
510 #define SQLITE_OPEN_TRANSIENT_DB 0x00000400
511 #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800
512 #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000
513 #define SQLITE_OPEN_SUBJOURNAL 0x00002000
514 #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000
515 #define SQLITE_OPEN_NOMUTEX 0x00008000
518 ** CAPI3REF: Device Characteristics {H10240} <H11120>
520 ** The xDeviceCapabilities method of the [sqlite3_io_methods]
521 ** object returns an integer which is a vector of the these
522 ** bit values expressing I/O characteristics of the mass storage
523 ** device that holds the file that the [sqlite3_io_methods]
526 ** The SQLITE_IOCAP_ATOMIC property means that all writes of
527 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
528 ** mean that writes of blocks that are nnn bytes in size and
529 ** are aligned to an address which is an integer multiple of
530 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
531 ** that when data is appended to a file, the data is appended
532 ** first then the size of the file is extended, never the other
533 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
534 ** information is written to disk in the same order as calls
537 #define SQLITE_IOCAP_ATOMIC 0x00000001
538 #define SQLITE_IOCAP_ATOMIC512 0x00000002
539 #define SQLITE_IOCAP_ATOMIC1K 0x00000004
540 #define SQLITE_IOCAP_ATOMIC2K 0x00000008
541 #define SQLITE_IOCAP_ATOMIC4K 0x00000010
542 #define SQLITE_IOCAP_ATOMIC8K 0x00000020
543 #define SQLITE_IOCAP_ATOMIC16K 0x00000040
544 #define SQLITE_IOCAP_ATOMIC32K 0x00000080
545 #define SQLITE_IOCAP_ATOMIC64K 0x00000100
546 #define SQLITE_IOCAP_SAFE_APPEND 0x00000200
547 #define SQLITE_IOCAP_SEQUENTIAL 0x00000400
550 ** CAPI3REF: File Locking Levels {H10250} <H11120> <H11310>
552 ** SQLite uses one of these integer values as the second
553 ** argument to calls it makes to the xLock() and xUnlock() methods
554 ** of an [sqlite3_io_methods] object.
556 #define SQLITE_LOCK_NONE 0
557 #define SQLITE_LOCK_SHARED 1
558 #define SQLITE_LOCK_RESERVED 2
559 #define SQLITE_LOCK_PENDING 3
560 #define SQLITE_LOCK_EXCLUSIVE 4
563 ** CAPI3REF: Synchronization Type Flags {H10260} <H11120>
565 ** When SQLite invokes the xSync() method of an
566 ** [sqlite3_io_methods] object it uses a combination of
567 ** these integer values as the second argument.
569 ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
570 ** sync operation only needs to flush data to mass storage. Inode
571 ** information need not be flushed. The SQLITE_SYNC_NORMAL flag means
572 ** to use normal fsync() semantics. The SQLITE_SYNC_FULL flag means
573 ** to use Mac OS-X style fullsync instead of fsync().
575 #define SQLITE_SYNC_NORMAL 0x00002
576 #define SQLITE_SYNC_FULL 0x00003
577 #define SQLITE_SYNC_DATAONLY 0x00010
580 ** CAPI3REF: OS Interface Open File Handle {H11110} <S20110>
582 ** An [sqlite3_file] object represents an open file in the OS
583 ** interface layer. Individual OS interface implementations will
584 ** want to subclass this object by appending additional fields
585 ** for their own use. The pMethods entry is a pointer to an
586 ** [sqlite3_io_methods] object that defines methods for performing
587 ** I/O operations on the open file.
589 typedef struct sqlite3_file sqlite3_file;
590 struct sqlite3_file {
591 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
595 ** CAPI3REF: OS Interface File Virtual Methods Object {H11120} <S20110>
597 ** Every file opened by the [sqlite3_vfs] xOpen method populates an
598 ** [sqlite3_file] object (or, more commonly, a subclass of the
599 ** [sqlite3_file] object) with a pointer to an instance of this object.
600 ** This object defines the methods used to perform various operations
601 ** against the open file represented by the [sqlite3_file] object.
603 ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
604 ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
605 ** The second choice is a Mac OS-X style fullsync. The [SQLITE_SYNC_DATAONLY]
606 ** flag may be ORed in to indicate that only the data of the file
607 ** and not its inode needs to be synced.
609 ** The integer values to xLock() and xUnlock() are one of
611 ** <li> [SQLITE_LOCK_NONE],
612 ** <li> [SQLITE_LOCK_SHARED],
613 ** <li> [SQLITE_LOCK_RESERVED],
614 ** <li> [SQLITE_LOCK_PENDING], or
615 ** <li> [SQLITE_LOCK_EXCLUSIVE].
617 ** xLock() increases the lock. xUnlock() decreases the lock.
618 ** The xCheckReservedLock() method checks whether any database connection,
619 ** either in this process or in some other process, is holding a RESERVED,
620 ** PENDING, or EXCLUSIVE lock on the file. It returns true
621 ** if such a lock exists and false otherwise.
623 ** The xFileControl() method is a generic interface that allows custom
624 ** VFS implementations to directly control an open file using the
625 ** [sqlite3_file_control()] interface. The second "op" argument is an
626 ** integer opcode. The third argument is a generic pointer intended to
627 ** point to a structure that may contain arguments or space in which to
628 ** write return values. Potential uses for xFileControl() might be
629 ** functions to enable blocking locks with timeouts, to change the
630 ** locking strategy (for example to use dot-file locks), to inquire
631 ** about the status of a lock, or to break stale locks. The SQLite
632 ** core reserves all opcodes less than 100 for its own use.
633 ** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
634 ** Applications that define a custom xFileControl method should use opcodes
635 ** greater than 100 to avoid conflicts.
637 ** The xSectorSize() method returns the sector size of the
638 ** device that underlies the file. The sector size is the
639 ** minimum write that can be performed without disturbing
640 ** other bytes in the file. The xDeviceCharacteristics()
641 ** method returns a bit vector describing behaviors of the
642 ** underlying device:
645 ** <li> [SQLITE_IOCAP_ATOMIC]
646 ** <li> [SQLITE_IOCAP_ATOMIC512]
647 ** <li> [SQLITE_IOCAP_ATOMIC1K]
648 ** <li> [SQLITE_IOCAP_ATOMIC2K]
649 ** <li> [SQLITE_IOCAP_ATOMIC4K]
650 ** <li> [SQLITE_IOCAP_ATOMIC8K]
651 ** <li> [SQLITE_IOCAP_ATOMIC16K]
652 ** <li> [SQLITE_IOCAP_ATOMIC32K]
653 ** <li> [SQLITE_IOCAP_ATOMIC64K]
654 ** <li> [SQLITE_IOCAP_SAFE_APPEND]
655 ** <li> [SQLITE_IOCAP_SEQUENTIAL]
658 ** The SQLITE_IOCAP_ATOMIC property means that all writes of
659 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
660 ** mean that writes of blocks that are nnn bytes in size and
661 ** are aligned to an address which is an integer multiple of
662 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
663 ** that when data is appended to a file, the data is appended
664 ** first then the size of the file is extended, never the other
665 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
666 ** information is written to disk in the same order as calls
669 typedef struct sqlite3_io_methods sqlite3_io_methods;
670 struct sqlite3_io_methods {
672 int (*xClose)(sqlite3_file*);
673 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
674 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
675 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
676 int (*xSync)(sqlite3_file*, int flags);
677 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
678 int (*xLock)(sqlite3_file*, int);
679 int (*xUnlock)(sqlite3_file*, int);
680 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
681 int (*xFileControl)(sqlite3_file*, int op, void *pArg);
682 int (*xSectorSize)(sqlite3_file*);
683 int (*xDeviceCharacteristics)(sqlite3_file*);
684 /* Additional methods may be added in future releases */
688 ** CAPI3REF: Standard File Control Opcodes {H11310} <S30800>
690 ** These integer constants are opcodes for the xFileControl method
691 ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
694 ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
695 ** opcode causes the xFileControl method to write the current state of
696 ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
697 ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
698 ** into an integer that the pArg argument points to. This capability
699 ** is used during testing and only needs to be supported when SQLITE_TEST
702 #define SQLITE_FCNTL_LOCKSTATE 1
705 ** CAPI3REF: Mutex Handle {H17110} <S20130>
707 ** The mutex module within SQLite defines [sqlite3_mutex] to be an
708 ** abstract type for a mutex object. The SQLite core never looks
709 ** at the internal representation of an [sqlite3_mutex]. It only
710 ** deals with pointers to the [sqlite3_mutex] object.
712 ** Mutexes are created using [sqlite3_mutex_alloc()].
714 typedef struct sqlite3_mutex sqlite3_mutex;
717 ** CAPI3REF: OS Interface Object {H11140} <S20100>
719 ** An instance of the sqlite3_vfs object defines the interface between
720 ** the SQLite core and the underlying operating system. The "vfs"
721 ** in the name of the object stands for "virtual file system".
723 ** The value of the iVersion field is initially 1 but may be larger in
724 ** future versions of SQLite. Additional fields may be appended to this
725 ** object when the iVersion value is increased. Note that the structure
726 ** of the sqlite3_vfs object changes in the transaction between
727 ** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
730 ** The szOsFile field is the size of the subclassed [sqlite3_file]
731 ** structure used by this VFS. mxPathname is the maximum length of
732 ** a pathname in this VFS.
734 ** Registered sqlite3_vfs objects are kept on a linked list formed by
735 ** the pNext pointer. The [sqlite3_vfs_register()]
736 ** and [sqlite3_vfs_unregister()] interfaces manage this list
737 ** in a thread-safe way. The [sqlite3_vfs_find()] interface
738 ** searches the list. Neither the application code nor the VFS
739 ** implementation should use the pNext pointer.
741 ** The pNext field is the only field in the sqlite3_vfs
742 ** structure that SQLite will ever modify. SQLite will only access
743 ** or modify this field while holding a particular static mutex.
744 ** The application should never modify anything within the sqlite3_vfs
745 ** object once the object has been registered.
747 ** The zName field holds the name of the VFS module. The name must
748 ** be unique across all VFS modules.
750 ** {H11141} SQLite will guarantee that the zFilename parameter to xOpen
751 ** is either a NULL pointer or string obtained
752 ** from xFullPathname(). SQLite further guarantees that
753 ** the string will be valid and unchanged until xClose() is
754 ** called. {END} Because of the previous sentense,
755 ** the [sqlite3_file] can safely store a pointer to the
756 ** filename if it needs to remember the filename for some reason.
757 ** If the zFilename parameter is xOpen is a NULL pointer then xOpen
758 ** must invite its own temporary name for the file. Whenever the
759 ** xFilename parameter is NULL it will also be the case that the
760 ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
762 ** {H11142} The flags argument to xOpen() includes all bits set in
763 ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
764 ** or [sqlite3_open16()] is used, then flags includes at least
765 ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. {END}
766 ** If xOpen() opens a file read-only then it sets *pOutFlags to
767 ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
769 ** {H11143} SQLite will also add one of the following flags to the xOpen()
770 ** call, depending on the object being opened:
773 ** <li> [SQLITE_OPEN_MAIN_DB]
774 ** <li> [SQLITE_OPEN_MAIN_JOURNAL]
775 ** <li> [SQLITE_OPEN_TEMP_DB]
776 ** <li> [SQLITE_OPEN_TEMP_JOURNAL]
777 ** <li> [SQLITE_OPEN_TRANSIENT_DB]
778 ** <li> [SQLITE_OPEN_SUBJOURNAL]
779 ** <li> [SQLITE_OPEN_MASTER_JOURNAL]
782 ** The file I/O implementation can use the object type flags to
783 ** change the way it deals with files. For example, an application
784 ** that does not care about crash recovery or rollback might make
785 ** the open of a journal file a no-op. Writes to this journal would
786 ** also be no-ops, and any attempt to read the journal would return
787 ** SQLITE_IOERR. Or the implementation might recognize that a database
788 ** file will be doing page-aligned sector reads and writes in a random
789 ** order and set up its I/O subsystem accordingly.
791 ** SQLite might also add one of the following flags to the xOpen method:
794 ** <li> [SQLITE_OPEN_DELETEONCLOSE]
795 ** <li> [SQLITE_OPEN_EXCLUSIVE]
798 ** {H11145} The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
799 ** deleted when it is closed. {H11146} The [SQLITE_OPEN_DELETEONCLOSE]
800 ** will be set for TEMP databases, journals and for subjournals.
802 ** {H11147} The [SQLITE_OPEN_EXCLUSIVE] flag means the file should be opened
803 ** for exclusive access. This flag is set for all files except
804 ** for the main database file.
806 ** {H11148} At least szOsFile bytes of memory are allocated by SQLite
807 ** to hold the [sqlite3_file] structure passed as the third
808 ** argument to xOpen. {END} The xOpen method does not have to
809 ** allocate the structure; it should just fill it in.
811 ** {H11149} The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
812 ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
813 ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
814 ** to test whether a file is at least readable. {END} The file can be a
817 ** {H11150} SQLite will always allocate at least mxPathname+1 bytes for the
818 ** output buffer xFullPathname. {H11151} The exact size of the output buffer
819 ** is also passed as a parameter to both methods. {END} If the output buffer
820 ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
821 ** handled as a fatal error by SQLite, vfs implementations should endeavor
822 ** to prevent this by setting mxPathname to a sufficiently large value.
824 ** The xRandomness(), xSleep(), and xCurrentTime() interfaces
825 ** are not strictly a part of the filesystem, but they are
826 ** included in the VFS structure for completeness.
827 ** The xRandomness() function attempts to return nBytes bytes
828 ** of good-quality randomness into zOut. The return value is
829 ** the actual number of bytes of randomness obtained.
830 ** The xSleep() method causes the calling thread to sleep for at
831 ** least the number of microseconds given. The xCurrentTime()
832 ** method returns a Julian Day Number for the current date and time.
834 typedef struct sqlite3_vfs sqlite3_vfs;
836 int iVersion; /* Structure version number */
837 int szOsFile; /* Size of subclassed sqlite3_file */
838 int mxPathname; /* Maximum file pathname length */
839 sqlite3_vfs *pNext; /* Next registered VFS */
840 const char *zName; /* Name of this virtual file system */
841 void *pAppData; /* Pointer to application-specific data */
842 int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
843 int flags, int *pOutFlags);
844 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
845 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
846 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
847 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
848 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
849 void *(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol);
850 void (*xDlClose)(sqlite3_vfs*, void*);
851 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
852 int (*xSleep)(sqlite3_vfs*, int microseconds);
853 int (*xCurrentTime)(sqlite3_vfs*, double*);
854 int (*xGetLastError)(sqlite3_vfs*, int, char *);
855 /* New fields may be appended in figure versions. The iVersion
856 ** value will increment whenever this happens. */
860 ** CAPI3REF: Flags for the xAccess VFS method {H11190} <H11140>
862 ** {H11191} These integer constants can be used as the third parameter to
863 ** the xAccess method of an [sqlite3_vfs] object. {END} They determine
864 ** what kind of permissions the xAccess method is looking for.
865 ** {H11192} With SQLITE_ACCESS_EXISTS, the xAccess method
866 ** simply checks whether the file exists.
867 ** {H11193} With SQLITE_ACCESS_READWRITE, the xAccess method
868 ** checks whether the file is both readable and writable.
869 ** {H11194} With SQLITE_ACCESS_READ, the xAccess method
870 ** checks whether the file is readable.
872 #define SQLITE_ACCESS_EXISTS 0
873 #define SQLITE_ACCESS_READWRITE 1
874 #define SQLITE_ACCESS_READ 2
877 ** CAPI3REF: Initialize The SQLite Library {H10130} <S20000><S30100>
879 ** The sqlite3_initialize() routine initializes the
880 ** SQLite library. The sqlite3_shutdown() routine
881 ** deallocates any resources that were allocated by sqlite3_initialize().
883 ** A call to sqlite3_initialize() is an "effective" call if it is
884 ** the first time sqlite3_initialize() is invoked during the lifetime of
885 ** the process, or if it is the first time sqlite3_initialize() is invoked
886 ** following a call to sqlite3_shutdown(). Only an effective call
887 ** of sqlite3_initialize() does any initialization. All other calls
888 ** are harmless no-ops.
890 ** Among other things, sqlite3_initialize() shall invoke
891 ** sqlite3_os_init(). Similarly, sqlite3_shutdown()
892 ** shall invoke sqlite3_os_end().
894 ** The sqlite3_initialize() routine returns SQLITE_OK on success.
895 ** If for some reason, sqlite3_initialize() is unable to initialize
896 ** the library (perhaps it is unable to allocate a needed resource such
897 ** as a mutex) it returns an [error code] other than SQLITE_OK.
899 ** The sqlite3_initialize() routine is called internally by many other
900 ** SQLite interfaces so that an application usually does not need to
901 ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
902 ** calls sqlite3_initialize() so the SQLite library will be automatically
903 ** initialized when [sqlite3_open()] is called if it has not be initialized
904 ** already. However, if SQLite is compiled with the SQLITE_OMIT_AUTOINIT
905 ** compile-time option, then the automatic calls to sqlite3_initialize()
906 ** are omitted and the application must call sqlite3_initialize() directly
907 ** prior to using any other SQLite interface. For maximum portability,
908 ** it is recommended that applications always invoke sqlite3_initialize()
909 ** directly prior to using any other SQLite interface. Future releases
910 ** of SQLite may require this. In other words, the behavior exhibited
911 ** when SQLite is compiled with SQLITE_OMIT_AUTOINIT might become the
912 ** default behavior in some future release of SQLite.
914 ** The sqlite3_os_init() routine does operating-system specific
915 ** initialization of the SQLite library. The sqlite3_os_end()
916 ** routine undoes the effect of sqlite3_os_init(). Typical tasks
917 ** performed by these routines include allocation or deallocation
918 ** of static resources, initialization of global variables,
919 ** setting up a default [sqlite3_vfs] module, or setting up
920 ** a default configuration using [sqlite3_config()].
922 ** The application should never invoke either sqlite3_os_init()
923 ** or sqlite3_os_end() directly. The application should only invoke
924 ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
925 ** interface is called automatically by sqlite3_initialize() and
926 ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
927 ** implementations for sqlite3_os_init() and sqlite3_os_end()
928 ** are built into SQLite when it is compiled for unix, windows, or os/2.
929 ** When built for other platforms (using the SQLITE_OS_OTHER=1 compile-time
930 ** option) the application must supply a suitable implementation for
931 ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
932 ** implementation of sqlite3_os_init() or sqlite3_os_end()
933 ** must return SQLITE_OK on success and some other [error code] upon
936 int sqlite3_initialize(void);
937 int sqlite3_shutdown(void);
938 int sqlite3_os_init(void);
939 int sqlite3_os_end(void);
942 ** CAPI3REF: Configuring The SQLite Library {H10145} <S20000><S30200>
945 ** The sqlite3_config() interface is used to make global configuration
946 ** changes to SQLite in order to tune SQLite to the specific needs of
947 ** the application. The default configuration is recommended for most
948 ** applications and so this routine is usually not necessary. It is
949 ** provided to support rare applications with unusual needs.
951 ** The sqlite3_config() interface is not threadsafe. The application
952 ** must insure that no other SQLite interfaces are invoked by other
953 ** threads while sqlite3_config() is running. Furthermore, sqlite3_config()
954 ** may only be invoked prior to library initialization using
955 ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
956 ** Note, however, that sqlite3_config() can be called as part of the
957 ** implementation of an application-defined [sqlite3_os_init()].
959 ** The first argument to sqlite3_config() is an integer
960 ** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines
961 ** what property of SQLite is to be configured. Subsequent arguments
962 ** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | configuration option]
963 ** in the first argument.
965 ** When a configuration option is set, sqlite3_config() returns SQLITE_OK.
966 ** If the option is unknown or SQLite is unable to set the option
967 ** then this routine returns a non-zero [error code].
969 int sqlite3_config(int, ...);
972 ** CAPI3REF: Configure database connections {H10180} <S20000>
975 ** The sqlite3_db_config() interface is used to make configuration
976 ** changes to a [database connection]. The interface is similar to
977 ** [sqlite3_config()] except that the changes apply to a single
978 ** [database connection] (specified in the first argument). The
979 ** sqlite3_db_config() interface can only be used immediately after
980 ** the database connection is created using [sqlite3_open()],
981 ** [sqlite3_open16()], or [sqlite3_open_v2()].
983 ** The second argument to sqlite3_db_config(D,V,...) is the
984 ** configuration verb - an integer code that indicates what
985 ** aspect of the [database connection] is being configured.
986 ** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE].
987 ** New verbs are likely to be added in future releases of SQLite.
988 ** Additional arguments depend on the verb.
990 int sqlite3_db_config(sqlite3*, int op, ...);
993 ** CAPI3REF: Memory Allocation Routines {H10155} <S20120>
996 ** An instance of this object defines the interface between SQLite
997 ** and low-level memory allocation routines.
999 ** This object is used in only one place in the SQLite interface.
1000 ** A pointer to an instance of this object is the argument to
1001 ** [sqlite3_config()] when the configuration option is
1002 ** [SQLITE_CONFIG_MALLOC]. By creating an instance of this object
1003 ** and passing it to [sqlite3_config()] during configuration, an
1004 ** application can specify an alternative memory allocation subsystem
1005 ** for SQLite to use for all of its dynamic memory needs.
1007 ** Note that SQLite comes with a built-in memory allocator that is
1008 ** perfectly adequate for the overwhelming majority of applications
1009 ** and that this object is only useful to a tiny minority of applications
1010 ** with specialized memory allocation requirements. This object is
1011 ** also used during testing of SQLite in order to specify an alternative
1012 ** memory allocator that simulates memory out-of-memory conditions in
1013 ** order to verify that SQLite recovers gracefully from such
1016 ** The xMalloc, xFree, and xRealloc methods must work like the
1017 ** malloc(), free(), and realloc() functions from the standard library.
1019 ** xSize should return the allocated size of a memory allocation
1020 ** previously obtained from xMalloc or xRealloc. The allocated size
1021 ** is always at least as big as the requested size but may be larger.
1023 ** The xRoundup method returns what would be the allocated size of
1024 ** a memory allocation given a particular requested size. Most memory
1025 ** allocators round up memory allocations at least to the next multiple
1026 ** of 8. Some allocators round up to a larger multiple or to a power of 2.
1028 ** The xInit method initializes the memory allocator. (For example,
1029 ** it might allocate any require mutexes or initialize internal data
1030 ** structures. The xShutdown method is invoked (indirectly) by
1031 ** [sqlite3_shutdown()] and should deallocate any resources acquired
1032 ** by xInit. The pAppData pointer is used as the only parameter to
1033 ** xInit and xShutdown.
1035 typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1036 struct sqlite3_mem_methods {
1037 void *(*xMalloc)(int); /* Memory allocation function */
1038 void (*xFree)(void*); /* Free a prior allocation */
1039 void *(*xRealloc)(void*,int); /* Resize an allocation */
1040 int (*xSize)(void*); /* Return the size of an allocation */
1041 int (*xRoundup)(int); /* Round up request size to allocation size */
1042 int (*xInit)(void*); /* Initialize the memory allocator */
1043 void (*xShutdown)(void*); /* Deinitialize the memory allocator */
1044 void *pAppData; /* Argument to xInit() and xShutdown() */
1048 ** CAPI3REF: Configuration Options {H10160} <S20000>
1051 ** These constants are the available integer configuration options that
1052 ** can be passed as the first argument to the [sqlite3_config()] interface.
1054 ** New configuration options may be added in future releases of SQLite.
1055 ** Existing configuration options might be discontinued. Applications
1056 ** should check the return code from [sqlite3_config()] to make sure that
1057 ** the call worked. The [sqlite3_config()] interface will return a
1058 ** non-zero [error code] if a discontinued or unsupported configuration option
1062 ** <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1063 ** <dd>There are no arguments to this option. This option disables
1064 ** all mutexing and puts SQLite into a mode where it can only be used
1065 ** by a single thread.</dd>
1067 ** <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1068 ** <dd>There are no arguments to this option. This option disables
1069 ** mutexing on [database connection] and [prepared statement] objects.
1070 ** The application is responsible for serializing access to
1071 ** [database connections] and [prepared statements]. But other mutexes
1072 ** are enabled so that SQLite will be safe to use in a multi-threaded
1073 ** environment.</dd>
1075 ** <dt>SQLITE_CONFIG_SERIALIZED</dt>
1076 ** <dd>There are no arguments to this option. This option enables
1077 ** all mutexes including the recursive
1078 ** mutexes on [database connection] and [prepared statement] objects.
1079 ** In this mode (which is the default when SQLite is compiled with
1080 ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1081 ** to [database connections] and [prepared statements] so that the
1082 ** application is free to use the same [database connection] or the
1083 ** same [prepared statement] in different threads at the same time.
1085 ** <p>This configuration option merely sets the default mutex
1086 ** behavior to serialize access to [database connections]. Individual
1087 ** [database connections] can override this setting
1088 ** using the [SQLITE_OPEN_NOMUTEX] flag to [sqlite3_open_v2()].</p></dd>
1090 ** <dt>SQLITE_CONFIG_MALLOC</dt>
1091 ** <dd>This option takes a single argument which is a pointer to an
1092 ** instance of the [sqlite3_mem_methods] structure. The argument specifies
1093 ** alternative low-level memory allocation routines to be used in place of
1094 ** the memory allocation routines built into SQLite.</dd>
1096 ** <dt>SQLITE_CONFIG_GETMALLOC</dt>
1097 ** <dd>This option takes a single argument which is a pointer to an
1098 ** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods]
1099 ** structure is filled with the currently defined memory allocation routines.
1100 ** This option can be used to overload the default memory allocation
1101 ** routines with a wrapper that simulations memory allocation failure or
1102 ** tracks memory usage, for example.</dd>
1104 ** <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1105 ** <dd>This option takes single argument of type int, interpreted as a
1106 ** boolean, which enables or disables the collection of memory allocation
1107 ** statistics. When disabled, the following SQLite interfaces become
1110 ** <li> [sqlite3_memory_used()]
1111 ** <li> [sqlite3_memory_highwater()]
1112 ** <li> [sqlite3_soft_heap_limit()]
1113 ** <li> [sqlite3_status()]
1117 ** <dt>SQLITE_CONFIG_SCRATCH</dt>
1118 ** <dd>This option specifies a static memory buffer that SQLite can use for
1119 ** scratch memory. There are three arguments: A pointer to the memory, the
1120 ** size of each scratch buffer (sz), and the number of buffers (N). The sz
1121 ** argument must be a multiple of 16. The sz parameter should be a few bytes
1122 ** larger than the actual scratch space required due internal overhead.
1124 ** argument should point to an allocation of at least sz*N bytes of memory.
1125 ** SQLite will use no more than one scratch buffer at once per thread, so
1126 ** N should be set to the expected maximum number of threads. The sz
1127 ** parameter should be 6 times the size of the largest database page size.
1128 ** Scratch buffers are used as part of the btree balance operation. If
1129 ** The btree balancer needs additional memory beyond what is provided by
1130 ** scratch buffers or if no scratch buffer space is specified, then SQLite
1131 ** goes to [sqlite3_malloc()] to obtain the memory it needs.</dd>
1133 ** <dt>SQLITE_CONFIG_PAGECACHE</dt>
1134 ** <dd>This option specifies a static memory buffer that SQLite can use for
1135 ** the database page cache. There are three arguments: A pointer to the
1136 ** memory, the size of each page buffer (sz), and the number of pages (N).
1137 ** The sz argument must be a power of two between 512 and 32768. The first
1138 ** argument should point to an allocation of at least sz*N bytes of memory.
1139 ** SQLite will use the memory provided by the first argument to satisfy its
1140 ** memory needs for the first N pages that it adds to cache. If additional
1141 ** page cache memory is needed beyond what is provided by this option, then
1142 ** SQLite goes to [sqlite3_malloc()] for the additional storage space.
1143 ** The implementation might use one or more of the N buffers to hold
1144 ** memory accounting information. </dd>
1146 ** <dt>SQLITE_CONFIG_HEAP</dt>
1147 ** <dd>This option specifies a static memory buffer that SQLite will use
1148 ** for all of its dynamic memory allocation needs beyond those provided
1149 ** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
1150 ** There are three arguments: A pointer to the memory, the number of
1151 ** bytes in the memory buffer, and the minimum allocation size. If
1152 ** the first pointer (the memory pointer) is NULL, then SQLite reverts
1153 ** to using its default memory allocator (the system malloc() implementation),
1154 ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. If the
1155 ** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
1156 ** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
1157 ** allocator is engaged to handle all of SQLites memory allocation needs.</dd>
1159 ** <dt>SQLITE_CONFIG_MUTEX</dt>
1160 ** <dd>This option takes a single argument which is a pointer to an
1161 ** instance of the [sqlite3_mutex_methods] structure. The argument specifies
1162 ** alternative low-level mutex routines to be used in place
1163 ** the mutex routines built into SQLite.</dd>
1165 ** <dt>SQLITE_CONFIG_GETMUTEX</dt>
1166 ** <dd>This option takes a single argument which is a pointer to an
1167 ** instance of the [sqlite3_mutex_methods] structure. The
1168 ** [sqlite3_mutex_methods]
1169 ** structure is filled with the currently defined mutex routines.
1170 ** This option can be used to overload the default mutex allocation
1171 ** routines with a wrapper used to track mutex usage for performance
1172 ** profiling or testing, for example.</dd>
1174 ** <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1175 ** <dd>This option takes two arguments that determine the default
1176 ** memory allcation lookaside optimization. The first argument is the
1177 ** size of each lookaside buffer slot and the second is the number of
1178 ** slots allocated to each database connection.</dd>
1182 #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
1183 #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
1184 #define SQLITE_CONFIG_SERIALIZED 3 /* nil */
1185 #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
1186 #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
1187 #define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */
1188 #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
1189 #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
1190 #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
1191 #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
1192 #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
1193 #define SQLITE_CONFIG_CHUNKALLOC 12 /* int threshold */
1194 #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
1197 ** CAPI3REF: Configuration Options {H10170} <S20000>
1200 ** These constants are the available integer configuration options that
1201 ** can be passed as the second argument to the [sqlite3_db_config()] interface.
1203 ** New configuration options may be added in future releases of SQLite.
1204 ** Existing configuration options might be discontinued. Applications
1205 ** should check the return code from [sqlite3_db_config()] to make sure that
1206 ** the call worked. The [sqlite3_db_config()] interface will return a
1207 ** non-zero [error code] if a discontinued or unsupported configuration option
1211 ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
1212 ** <dd>This option takes three additional arguments that determine the
1213 ** [lookaside memory allocator] configuration for the [database connection].
1214 ** The first argument (the third parameter to [sqlite3_db_config()] is a
1215 ** pointer to a memory buffer to use for lookaside memory. The first
1216 ** argument may be NULL in which case SQLite will allocate the lookaside
1217 ** buffer itself using [sqlite3_malloc()]. The second argument is the
1218 ** size of each lookaside buffer slot and the third argument is the number of
1219 ** slots. The size of the buffer in the first argument must be greater than
1220 ** or equal to the product of the second and third arguments.</dd>
1224 #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
1228 ** CAPI3REF: Enable Or Disable Extended Result Codes {H12200} <S10700>
1230 ** The sqlite3_extended_result_codes() routine enables or disables the
1231 ** [extended result codes] feature of SQLite. The extended result
1232 ** codes are disabled by default for historical compatibility considerations.
1236 ** {H12201} Each new [database connection] shall have the
1237 ** [extended result codes] feature disabled by default.
1239 ** {H12202} The [sqlite3_extended_result_codes(D,F)] interface shall enable
1240 ** [extended result codes] for the [database connection] D
1241 ** if the F parameter is true, or disable them if F is false.
1243 int sqlite3_extended_result_codes(sqlite3*, int onoff);
1246 ** CAPI3REF: Last Insert Rowid {H12220} <S10700>
1248 ** Each entry in an SQLite table has a unique 64-bit signed
1249 ** integer key called the "rowid". The rowid is always available
1250 ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
1251 ** names are not also used by explicitly declared columns. If
1252 ** the table has a column of type INTEGER PRIMARY KEY then that column
1253 ** is another alias for the rowid.
1255 ** This routine returns the rowid of the most recent
1256 ** successful INSERT into the database from the [database connection]
1257 ** in the first argument. If no successful INSERTs
1258 ** have ever occurred on that database connection, zero is returned.
1260 ** If an INSERT occurs within a trigger, then the rowid of the inserted
1261 ** row is returned by this routine as long as the trigger is running.
1262 ** But once the trigger terminates, the value returned by this routine
1263 ** reverts to the last value inserted before the trigger fired.
1265 ** An INSERT that fails due to a constraint violation is not a
1266 ** successful INSERT and does not change the value returned by this
1267 ** routine. Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
1268 ** and INSERT OR ABORT make no changes to the return value of this
1269 ** routine when their insertion fails. When INSERT OR REPLACE
1270 ** encounters a constraint violation, it does not fail. The
1271 ** INSERT continues to completion after deleting rows that caused
1272 ** the constraint problem so INSERT OR REPLACE will always change
1273 ** the return value of this interface.
1275 ** For the purposes of this routine, an INSERT is considered to
1276 ** be successful even if it is subsequently rolled back.
1280 ** {H12221} The [sqlite3_last_insert_rowid()] function returns the rowid
1281 ** of the most recent successful INSERT performed on the same
1282 ** [database connection] and within the same or higher level
1283 ** trigger context, or zero if there have been no qualifying inserts.
1285 ** {H12223} The [sqlite3_last_insert_rowid()] function returns the
1286 ** same value when called from the same trigger context
1287 ** immediately before and after a ROLLBACK.
1291 ** {A12232} If a separate thread performs a new INSERT on the same
1292 ** database connection while the [sqlite3_last_insert_rowid()]
1293 ** function is running and thus changes the last insert rowid,
1294 ** then the value returned by [sqlite3_last_insert_rowid()] is
1295 ** unpredictable and might not equal either the old or the new
1296 ** last insert rowid.
1298 sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
1301 ** CAPI3REF: Count The Number Of Rows Modified {H12240} <S10600>
1303 ** This function returns the number of database rows that were changed
1304 ** or inserted or deleted by the most recently completed SQL statement
1305 ** on the [database connection] specified by the first parameter.
1306 ** Only changes that are directly specified by the INSERT, UPDATE,
1307 ** or DELETE statement are counted. Auxiliary changes caused by
1308 ** triggers are not counted. Use the [sqlite3_total_changes()] function
1309 ** to find the total number of changes including changes caused by triggers.
1311 ** A "row change" is a change to a single row of a single table
1312 ** caused by an INSERT, DELETE, or UPDATE statement. Rows that
1313 ** are changed as side effects of REPLACE constraint resolution,
1314 ** rollback, ABORT processing, DROP TABLE, or by any other
1315 ** mechanisms do not count as direct row changes.
1317 ** A "trigger context" is a scope of execution that begins and
1318 ** ends with the script of a trigger. Most SQL statements are
1319 ** evaluated outside of any trigger. This is the "top level"
1320 ** trigger context. If a trigger fires from the top level, a
1321 ** new trigger context is entered for the duration of that one
1322 ** trigger. Subtriggers create subcontexts for their duration.
1324 ** Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
1325 ** not create a new trigger context.
1327 ** This function returns the number of direct row changes in the
1328 ** most recent INSERT, UPDATE, or DELETE statement within the same
1331 ** Thus, when called from the top level, this function returns the
1332 ** number of changes in the most recent INSERT, UPDATE, or DELETE
1333 ** that also occurred at the top level. Within the body of a trigger,
1334 ** the sqlite3_changes() interface can be called to find the number of
1335 ** changes in the most recently completed INSERT, UPDATE, or DELETE
1336 ** statement within the body of the same trigger.
1337 ** However, the number returned does not include changes
1338 ** caused by subtriggers since those have their own context.
1340 ** SQLite implements the command "DELETE FROM table" without a WHERE clause
1341 ** by dropping and recreating the table. (This is much faster than going
1342 ** through and deleting individual elements from the table.) Because of this
1343 ** optimization, the deletions in "DELETE FROM table" are not row changes and
1344 ** will not be counted by the sqlite3_changes() or [sqlite3_total_changes()]
1345 ** functions, regardless of the number of elements that were originally
1346 ** in the table. To get an accurate count of the number of rows deleted, use
1347 ** "DELETE FROM table WHERE 1" instead.
1351 ** {H12241} The [sqlite3_changes()] function shall return the number of
1352 ** row changes caused by the most recent INSERT, UPDATE,
1353 ** or DELETE statement on the same database connection and
1354 ** within the same or higher trigger context, or zero if there have
1355 ** not been any qualifying row changes.
1357 ** {H12243} Statements of the form "DELETE FROM tablename" with no
1358 ** WHERE clause shall cause subsequent calls to
1359 ** [sqlite3_changes()] to return zero, regardless of the
1360 ** number of rows originally in the table.
1364 ** {A12252} If a separate thread makes changes on the same database connection
1365 ** while [sqlite3_changes()] is running then the value returned
1366 ** is unpredictable and not meaningful.
1368 int sqlite3_changes(sqlite3*);
1371 ** CAPI3REF: Total Number Of Rows Modified {H12260} <S10600>
1373 ** This function returns the number of row changes caused by INSERT,
1374 ** UPDATE or DELETE statements since the [database connection] was opened.
1375 ** The count includes all changes from all trigger contexts. However,
1376 ** the count does not include changes used to implement REPLACE constraints,
1377 ** do rollbacks or ABORT processing, or DROP table processing.
1378 ** The changes are counted as soon as the statement that makes them is
1379 ** completed (when the statement handle is passed to [sqlite3_reset()] or
1380 ** [sqlite3_finalize()]).
1382 ** SQLite implements the command "DELETE FROM table" without a WHERE clause
1383 ** by dropping and recreating the table. (This is much faster than going
1384 ** through and deleting individual elements from the table.) Because of this
1385 ** optimization, the deletions in "DELETE FROM table" are not row changes and
1386 ** will not be counted by the sqlite3_changes() or [sqlite3_total_changes()]
1387 ** functions, regardless of the number of elements that were originally
1388 ** in the table. To get an accurate count of the number of rows deleted, use
1389 ** "DELETE FROM table WHERE 1" instead.
1391 ** See also the [sqlite3_changes()] interface.
1395 ** {H12261} The [sqlite3_total_changes()] returns the total number
1396 ** of row changes caused by INSERT, UPDATE, and/or DELETE
1397 ** statements on the same [database connection], in any
1398 ** trigger context, since the database connection was created.
1400 ** {H12263} Statements of the form "DELETE FROM tablename" with no
1401 ** WHERE clause shall not change the value returned
1402 ** by [sqlite3_total_changes()].
1406 ** {A12264} If a separate thread makes changes on the same database connection
1407 ** while [sqlite3_total_changes()] is running then the value
1408 ** returned is unpredictable and not meaningful.
1410 int sqlite3_total_changes(sqlite3*);
1413 ** CAPI3REF: Interrupt A Long-Running Query {H12270} <S30500>
1415 ** This function causes any pending database operation to abort and
1416 ** return at its earliest opportunity. This routine is typically
1417 ** called in response to a user action such as pressing "Cancel"
1418 ** or Ctrl-C where the user wants a long query operation to halt
1421 ** It is safe to call this routine from a thread different from the
1422 ** thread that is currently running the database operation. But it
1423 ** is not safe to call this routine with a [database connection] that
1424 ** is closed or might close before sqlite3_interrupt() returns.
1426 ** If an SQL operation is very nearly finished at the time when
1427 ** sqlite3_interrupt() is called, then it might not have an opportunity
1428 ** to be interrupted and might continue to completion.
1430 ** An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
1431 ** If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
1432 ** that is inside an explicit transaction, then the entire transaction
1433 ** will be rolled back automatically.
1435 ** A call to sqlite3_interrupt() has no effect on SQL statements
1436 ** that are started after sqlite3_interrupt() returns.
1440 ** {H12271} The [sqlite3_interrupt()] interface will force all running
1441 ** SQL statements associated with the same database connection
1442 ** to halt after processing at most one additional row of data.
1444 ** {H12272} Any SQL statement that is interrupted by [sqlite3_interrupt()]
1445 ** will return [SQLITE_INTERRUPT].
1449 ** {A12279} If the database connection closes while [sqlite3_interrupt()]
1450 ** is running then bad things will likely happen.
1452 void sqlite3_interrupt(sqlite3*);
1455 ** CAPI3REF: Determine If An SQL Statement Is Complete {H10510} <S70200>
1457 ** These routines are useful for command-line input to determine if the
1458 ** currently entered text seems to form complete a SQL statement or
1459 ** if additional input is needed before sending the text into
1460 ** SQLite for parsing. These routines return true if the input string
1461 ** appears to be a complete SQL statement. A statement is judged to be
1462 ** complete if it ends with a semicolon token and is not a fragment of a
1463 ** CREATE TRIGGER statement. Semicolons that are embedded within
1464 ** string literals or quoted identifier names or comments are not
1465 ** independent tokens (they are part of the token in which they are
1466 ** embedded) and thus do not count as a statement terminator.
1468 ** These routines do not parse the SQL statements thus
1469 ** will not detect syntactically incorrect SQL.
1473 ** {H10511} A successful evaluation of [sqlite3_complete()] or
1474 ** [sqlite3_complete16()] functions shall
1475 ** return a numeric 1 if and only if the last non-whitespace
1476 ** token in their input is a semicolon that is not in between
1477 ** the BEGIN and END of a CREATE TRIGGER statement.
1479 ** {H10512} If a memory allocation error occurs during an invocation
1480 ** of [sqlite3_complete()] or [sqlite3_complete16()] then the
1481 ** routine shall return [SQLITE_NOMEM].
1485 ** {A10512} The input to [sqlite3_complete()] must be a zero-terminated
1488 ** {A10513} The input to [sqlite3_complete16()] must be a zero-terminated
1489 ** UTF-16 string in native byte order.
1491 int sqlite3_complete(const char *sql);
1492 int sqlite3_complete16(const void *sql);
1495 ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {H12310} <S40400>
1497 ** This routine sets a callback function that might be invoked whenever
1498 ** an attempt is made to open a database table that another thread
1499 ** or process has locked.
1501 ** If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
1502 ** is returned immediately upon encountering the lock. If the busy callback
1503 ** is not NULL, then the callback will be invoked with two arguments.
1505 ** The first argument to the handler is a copy of the void* pointer which
1506 ** is the third argument to sqlite3_busy_handler(). The second argument to
1507 ** the handler callback is the number of times that the busy handler has
1508 ** been invoked for this locking event. If the
1509 ** busy callback returns 0, then no additional attempts are made to
1510 ** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
1511 ** If the callback returns non-zero, then another attempt
1512 ** is made to open the database for reading and the cycle repeats.
1514 ** The presence of a busy handler does not guarantee that it will be invoked
1515 ** when there is lock contention. If SQLite determines that invoking the busy
1516 ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
1517 ** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
1518 ** Consider a scenario where one process is holding a read lock that
1519 ** it is trying to promote to a reserved lock and
1520 ** a second process is holding a reserved lock that it is trying
1521 ** to promote to an exclusive lock. The first process cannot proceed
1522 ** because it is blocked by the second and the second process cannot
1523 ** proceed because it is blocked by the first. If both processes
1524 ** invoke the busy handlers, neither will make any progress. Therefore,
1525 ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
1526 ** will induce the first process to release its read lock and allow
1527 ** the second process to proceed.
1529 ** The default busy callback is NULL.
1531 ** The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
1532 ** when SQLite is in the middle of a large transaction where all the
1533 ** changes will not fit into the in-memory cache. SQLite will
1534 ** already hold a RESERVED lock on the database file, but it needs
1535 ** to promote this lock to EXCLUSIVE so that it can spill cache
1536 ** pages into the database file without harm to concurrent
1537 ** readers. If it is unable to promote the lock, then the in-memory
1538 ** cache will be left in an inconsistent state and so the error
1539 ** code is promoted from the relatively benign [SQLITE_BUSY] to
1540 ** the more severe [SQLITE_IOERR_BLOCKED]. This error code promotion
1541 ** forces an automatic rollback of the changes. See the
1542 ** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
1543 ** CorruptionFollowingBusyError</a> wiki page for a discussion of why
1544 ** this is important.
1546 ** There can only be a single busy handler defined for each
1547 ** [database connection]. Setting a new busy handler clears any
1548 ** previously set handler. Note that calling [sqlite3_busy_timeout()]
1549 ** will also set or clear the busy handler.
1553 ** {H12311} The [sqlite3_busy_handler(D,C,A)] function shall replace
1554 ** busy callback in the [database connection] D with a new
1555 ** a new busy handler C and application data pointer A.
1557 ** {H12312} Newly created [database connections] shall have a busy
1560 ** {H12314} When two or more [database connections] share a
1561 ** [sqlite3_enable_shared_cache | common cache],
1562 ** the busy handler for the database connection currently using
1563 ** the cache shall be invoked when the cache encounters a lock.
1565 ** {H12316} If a busy handler callback returns zero, then the SQLite interface
1566 ** that provoked the locking event shall return [SQLITE_BUSY].
1568 ** {H12318} SQLite shall invokes the busy handler with two arguments which
1569 ** are a copy of the pointer supplied by the 3rd parameter to
1570 ** [sqlite3_busy_handler()] and a count of the number of prior
1571 ** invocations of the busy handler for the same locking event.
1575 ** {A12319} A busy handler must not close the database connection
1576 ** or [prepared statement] that invoked the busy handler.
1578 int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
1581 ** CAPI3REF: Set A Busy Timeout {H12340} <S40410>
1583 ** This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
1584 ** for a specified amount of time when a table is locked. The handler
1585 ** will sleep multiple times until at least "ms" milliseconds of sleeping
1586 ** have accumulated. {H12343} After "ms" milliseconds of sleeping,
1587 ** the handler returns 0 which causes [sqlite3_step()] to return
1588 ** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
1590 ** Calling this routine with an argument less than or equal to zero
1591 ** turns off all busy handlers.
1593 ** There can only be a single busy handler for a particular
1594 ** [database connection] any any given moment. If another busy handler
1595 ** was defined (using [sqlite3_busy_handler()]) prior to calling
1596 ** this routine, that other busy handler is cleared.
1600 ** {H12341} The [sqlite3_busy_timeout()] function shall override any prior
1601 ** [sqlite3_busy_timeout()] or [sqlite3_busy_handler()] setting
1602 ** on the same [database connection].
1604 ** {H12343} If the 2nd parameter to [sqlite3_busy_timeout()] is less than
1605 ** or equal to zero, then the busy handler shall be cleared so that
1606 ** all subsequent locking events immediately return [SQLITE_BUSY].
1608 ** {H12344} If the 2nd parameter to [sqlite3_busy_timeout()] is a positive
1609 ** number N, then a busy handler shall be set that repeatedly calls
1610 ** the xSleep() method in the [sqlite3_vfs | VFS interface] until
1611 ** either the lock clears or until the cumulative sleep time
1612 ** reported back by xSleep() exceeds N milliseconds.
1614 int sqlite3_busy_timeout(sqlite3*, int ms);
1617 ** CAPI3REF: Convenience Routines For Running Queries {H12370} <S10000>
1619 ** Definition: A <b>result table</b> is memory data structure created by the
1620 ** [sqlite3_get_table()] interface. A result table records the
1621 ** complete query results from one or more queries.
1623 ** The table conceptually has a number of rows and columns. But
1624 ** these numbers are not part of the result table itself. These
1625 ** numbers are obtained separately. Let N be the number of rows
1626 ** and M be the number of columns.
1628 ** A result table is an array of pointers to zero-terminated UTF-8 strings.
1629 ** There are (N+1)*M elements in the array. The first M pointers point
1630 ** to zero-terminated strings that contain the names of the columns.
1631 ** The remaining entries all point to query results. NULL values result
1632 ** in NULL pointers. All other values are in their UTF-8 zero-terminated
1633 ** string representation as returned by [sqlite3_column_text()].
1635 ** A result table might consist of one or more memory allocations.
1636 ** It is not safe to pass a result table directly to [sqlite3_free()].
1637 ** A result table should be deallocated using [sqlite3_free_table()].
1639 ** As an example of the result table format, suppose a query result
1642 ** <blockquote><pre>
1644 ** -----------------------
1648 ** </pre></blockquote>
1650 ** There are two column (M==2) and three rows (N==3). Thus the
1651 ** result table has 8 entries. Suppose the result table is stored
1652 ** in an array names azResult. Then azResult holds this content:
1654 ** <blockquote><pre>
1655 ** azResult[0] = "Name";
1656 ** azResult[1] = "Age";
1657 ** azResult[2] = "Alice";
1658 ** azResult[3] = "43";
1659 ** azResult[4] = "Bob";
1660 ** azResult[5] = "28";
1661 ** azResult[6] = "Cindy";
1662 ** azResult[7] = "21";
1663 ** </pre></blockquote>
1665 ** The sqlite3_get_table() function evaluates one or more
1666 ** semicolon-separated SQL statements in the zero-terminated UTF-8
1667 ** string of its 2nd parameter. It returns a result table to the
1668 ** pointer given in its 3rd parameter.
1670 ** After the calling function has finished using the result, it should
1671 ** pass the pointer to the result table to sqlite3_free_table() in order to
1672 ** release the memory that was malloced. Because of the way the
1673 ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
1674 ** function must not try to call [sqlite3_free()] directly. Only
1675 ** [sqlite3_free_table()] is able to release the memory properly and safely.
1677 ** The sqlite3_get_table() interface is implemented as a wrapper around
1678 ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
1679 ** to any internal data structures of SQLite. It uses only the public
1680 ** interface defined here. As a consequence, errors that occur in the
1681 ** wrapper layer outside of the internal [sqlite3_exec()] call are not
1682 ** reflected in subsequent calls to [sqlite3_errcode()] or [sqlite3_errmsg()].
1686 ** {H12371} If a [sqlite3_get_table()] fails a memory allocation, then
1687 ** it shall free the result table under construction, abort the
1688 ** query in process, skip any subsequent queries, set the
1689 ** *pazResult output pointer to NULL and return [SQLITE_NOMEM].
1691 ** {H12373} If the pnColumn parameter to [sqlite3_get_table()] is not NULL
1692 ** then a successful invocation of [sqlite3_get_table()] shall
1693 ** write the number of columns in the
1694 ** result set of the query into *pnColumn.
1696 ** {H12374} If the pnRow parameter to [sqlite3_get_table()] is not NULL
1697 ** then a successful invocation of [sqlite3_get_table()] shall
1698 ** writes the number of rows in the
1699 ** result set of the query into *pnRow.
1701 ** {H12376} A successful invocation of [sqlite3_get_table()] that computes
1702 ** N rows of result with C columns per row shall make *pazResult
1703 ** point to an array of pointers to (N+1)*C strings where the first
1704 ** C strings are column names as obtained from
1705 ** [sqlite3_column_name()] and the rest are column result values
1706 ** obtained from [sqlite3_column_text()].
1708 ** {H12379} The values in the pazResult array returned by [sqlite3_get_table()]
1709 ** shall remain valid until cleared by [sqlite3_free_table()].
1711 ** {H12382} When an error occurs during evaluation of [sqlite3_get_table()]
1712 ** the function shall set *pazResult to NULL, write an error message
1713 ** into memory obtained from [sqlite3_malloc()], make
1714 ** **pzErrmsg point to that error message, and return a
1715 ** appropriate [error code].
1717 int sqlite3_get_table(
1718 sqlite3 *db, /* An open database */
1719 const char *zSql, /* SQL to be evaluated */
1720 char ***pazResult, /* Results of the query */
1721 int *pnRow, /* Number of result rows written here */
1722 int *pnColumn, /* Number of result columns written here */
1723 char **pzErrmsg /* Error msg written here */
1725 void sqlite3_free_table(char **result);
1728 ** CAPI3REF: Formatted String Printing Functions {H17400} <S70000><S20000>
1730 ** These routines are workalikes of the "printf()" family of functions
1731 ** from the standard C library.
1733 ** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
1734 ** results into memory obtained from [sqlite3_malloc()].
1735 ** The strings returned by these two routines should be
1736 ** released by [sqlite3_free()]. Both routines return a
1737 ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
1738 ** memory to hold the resulting string.
1740 ** In sqlite3_snprintf() routine is similar to "snprintf()" from
1741 ** the standard C library. The result is written into the
1742 ** buffer supplied as the second parameter whose size is given by
1743 ** the first parameter. Note that the order of the
1744 ** first two parameters is reversed from snprintf(). This is an
1745 ** historical accident that cannot be fixed without breaking
1746 ** backwards compatibility. Note also that sqlite3_snprintf()
1747 ** returns a pointer to its buffer instead of the number of
1748 ** characters actually written into the buffer. We admit that
1749 ** the number of characters written would be a more useful return
1750 ** value but we cannot change the implementation of sqlite3_snprintf()
1751 ** now without breaking compatibility.
1753 ** As long as the buffer size is greater than zero, sqlite3_snprintf()
1754 ** guarantees that the buffer is always zero-terminated. The first
1755 ** parameter "n" is the total size of the buffer, including space for
1756 ** the zero terminator. So the longest string that can be completely
1757 ** written will be n-1 characters.
1759 ** These routines all implement some additional formatting
1760 ** options that are useful for constructing SQL statements.
1761 ** All of the usual printf() formatting options apply. In addition, there
1762 ** is are "%q", "%Q", and "%z" options.
1764 ** The %q option works like %s in that it substitutes a null-terminated
1765 ** string from the argument list. But %q also doubles every '\'' character.
1766 ** %q is designed for use inside a string literal. By doubling each '\''
1767 ** character it escapes that character and allows it to be inserted into
1770 ** For example, assume the string variable zText contains text as follows:
1772 ** <blockquote><pre>
1773 ** char *zText = "It's a happy day!";
1774 ** </pre></blockquote>
1776 ** One can use this text in an SQL statement as follows:
1778 ** <blockquote><pre>
1779 ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
1780 ** sqlite3_exec(db, zSQL, 0, 0, 0);
1781 ** sqlite3_free(zSQL);
1782 ** </pre></blockquote>
1784 ** Because the %q format string is used, the '\'' character in zText
1785 ** is escaped and the SQL generated is as follows:
1787 ** <blockquote><pre>
1788 ** INSERT INTO table1 VALUES('It''s a happy day!')
1789 ** </pre></blockquote>
1791 ** This is correct. Had we used %s instead of %q, the generated SQL
1792 ** would have looked like this:
1794 ** <blockquote><pre>
1795 ** INSERT INTO table1 VALUES('It's a happy day!');
1796 ** </pre></blockquote>
1798 ** This second example is an SQL syntax error. As a general rule you should
1799 ** always use %q instead of %s when inserting text into a string literal.
1801 ** The %Q option works like %q except it also adds single quotes around
1802 ** the outside of the total string. Additionally, if the parameter in the
1803 ** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
1804 ** single quotes) in place of the %Q option. So, for example, one could say:
1806 ** <blockquote><pre>
1807 ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
1808 ** sqlite3_exec(db, zSQL, 0, 0, 0);
1809 ** sqlite3_free(zSQL);
1810 ** </pre></blockquote>
1812 ** The code above will render a correct SQL statement in the zSQL
1813 ** variable even if the zText variable is a NULL pointer.
1815 ** The "%z" formatting option works exactly like "%s" with the
1816 ** addition that after the string has been read and copied into
1817 ** the result, [sqlite3_free()] is called on the input string. {END}
1821 ** {H17403} The [sqlite3_mprintf()] and [sqlite3_vmprintf()] interfaces
1822 ** return either pointers to zero-terminated UTF-8 strings held in
1823 ** memory obtained from [sqlite3_malloc()] or NULL pointers if
1824 ** a call to [sqlite3_malloc()] fails.
1826 ** {H17406} The [sqlite3_snprintf()] interface writes a zero-terminated
1827 ** UTF-8 string into the buffer pointed to by the second parameter
1828 ** provided that the first parameter is greater than zero.
1830 ** {H17407} The [sqlite3_snprintf()] interface does not write slots of
1831 ** its output buffer (the second parameter) outside the range
1832 ** of 0 through N-1 (where N is the first parameter)
1833 ** regardless of the length of the string
1834 ** requested by the format specification.
1836 char *sqlite3_mprintf(const char*,...);
1837 char *sqlite3_vmprintf(const char*, va_list);
1838 char *sqlite3_snprintf(int,char*,const char*, ...);
1841 ** CAPI3REF: Memory Allocation Subsystem {H17300} <S20000>
1843 ** The SQLite core uses these three routines for all of its own
1844 ** internal memory allocation needs. "Core" in the previous sentence
1845 ** does not include operating-system specific VFS implementation. The
1846 ** Windows VFS uses native malloc() and free() for some operations.
1848 ** The sqlite3_malloc() routine returns a pointer to a block
1849 ** of memory at least N bytes in length, where N is the parameter.
1850 ** If sqlite3_malloc() is unable to obtain sufficient free
1851 ** memory, it returns a NULL pointer. If the parameter N to
1852 ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
1855 ** Calling sqlite3_free() with a pointer previously returned
1856 ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
1857 ** that it might be reused. The sqlite3_free() routine is
1858 ** a no-op if is called with a NULL pointer. Passing a NULL pointer
1859 ** to sqlite3_free() is harmless. After being freed, memory
1860 ** should neither be read nor written. Even reading previously freed
1861 ** memory might result in a segmentation fault or other severe error.
1862 ** Memory corruption, a segmentation fault, or other severe error
1863 ** might result if sqlite3_free() is called with a non-NULL pointer that
1864 ** was not obtained from sqlite3_malloc() or sqlite3_free().
1866 ** The sqlite3_realloc() interface attempts to resize a
1867 ** prior memory allocation to be at least N bytes, where N is the
1868 ** second parameter. The memory allocation to be resized is the first
1869 ** parameter. If the first parameter to sqlite3_realloc()
1870 ** is a NULL pointer then its behavior is identical to calling
1871 ** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
1872 ** If the second parameter to sqlite3_realloc() is zero or
1873 ** negative then the behavior is exactly the same as calling
1874 ** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
1875 ** sqlite3_realloc() returns a pointer to a memory allocation
1876 ** of at least N bytes in size or NULL if sufficient memory is unavailable.
1877 ** If M is the size of the prior allocation, then min(N,M) bytes
1878 ** of the prior allocation are copied into the beginning of buffer returned
1879 ** by sqlite3_realloc() and the prior allocation is freed.
1880 ** If sqlite3_realloc() returns NULL, then the prior allocation
1883 ** The memory returned by sqlite3_malloc() and sqlite3_realloc()
1884 ** is always aligned to at least an 8 byte boundary. {END}
1886 ** The default implementation of the memory allocation subsystem uses
1887 ** the malloc(), realloc() and free() provided by the standard C library.
1888 ** {H17382} However, if SQLite is compiled with the
1889 ** SQLITE_MEMORY_SIZE=<i>NNN</i> C preprocessor macro (where <i>NNN</i>
1890 ** is an integer), then SQLite create a static array of at least
1891 ** <i>NNN</i> bytes in size and uses that array for all of its dynamic
1892 ** memory allocation needs. {END} Additional memory allocator options
1893 ** may be added in future releases.
1895 ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
1896 ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
1897 ** implementation of these routines to be omitted. That capability
1898 ** is no longer provided. Only built-in memory allocators can be used.
1900 ** The Windows OS interface layer calls
1901 ** the system malloc() and free() directly when converting
1902 ** filenames between the UTF-8 encoding used by SQLite
1903 ** and whatever filename encoding is used by the particular Windows
1904 ** installation. Memory allocation errors are detected, but
1905 ** they are reported back as [SQLITE_CANTOPEN] or
1906 ** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
1910 ** {H17303} The [sqlite3_malloc(N)] interface returns either a pointer to
1911 ** a newly checked-out block of at least N bytes of memory
1912 ** that is 8-byte aligned, or it returns NULL if it is unable
1913 ** to fulfill the request.
1915 ** {H17304} The [sqlite3_malloc(N)] interface returns a NULL pointer if
1916 ** N is less than or equal to zero.
1918 ** {H17305} The [sqlite3_free(P)] interface releases memory previously
1919 ** returned from [sqlite3_malloc()] or [sqlite3_realloc()],
1920 ** making it available for reuse.
1922 ** {H17306} A call to [sqlite3_free(NULL)] is a harmless no-op.
1924 ** {H17310} A call to [sqlite3_realloc(0,N)] is equivalent to a call
1925 ** to [sqlite3_malloc(N)].
1927 ** {H17312} A call to [sqlite3_realloc(P,0)] is equivalent to a call
1928 ** to [sqlite3_free(P)].
1930 ** {H17315} The SQLite core uses [sqlite3_malloc()], [sqlite3_realloc()],
1931 ** and [sqlite3_free()] for all of its memory allocation and
1932 ** deallocation needs.
1934 ** {H17318} The [sqlite3_realloc(P,N)] interface returns either a pointer
1935 ** to a block of checked-out memory of at least N bytes in size
1936 ** that is 8-byte aligned, or a NULL pointer.
1938 ** {H17321} When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
1939 ** copies the first K bytes of content from P into the newly
1940 ** allocated block, where K is the lesser of N and the size of
1943 ** {H17322} When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
1944 ** releases the buffer P.
1946 ** {H17323} When [sqlite3_realloc(P,N)] returns NULL, the buffer P is
1947 ** not modified or released.
1951 ** {A17350} The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
1952 ** must be either NULL or else pointers obtained from a prior
1953 ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
1954 ** not yet been released.
1956 ** {A17351} The application must not read or write any part of
1957 ** a block of memory after it has been released using
1958 ** [sqlite3_free()] or [sqlite3_realloc()].
1960 void *sqlite3_malloc(int);
1961 void *sqlite3_realloc(void*, int);
1962 void sqlite3_free(void*);
1965 ** CAPI3REF: Memory Allocator Statistics {H17370} <S30210>
1967 ** SQLite provides these two interfaces for reporting on the status
1968 ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
1969 ** routines, which form the built-in memory allocation subsystem.
1973 ** {H17371} The [sqlite3_memory_used()] routine returns the number of bytes
1974 ** of memory currently outstanding (malloced but not freed).
1976 ** {H17373} The [sqlite3_memory_highwater()] routine returns the maximum
1977 ** value of [sqlite3_memory_used()] since the high-water mark
1980 ** {H17374} The values returned by [sqlite3_memory_used()] and
1981 ** [sqlite3_memory_highwater()] include any overhead
1982 ** added by SQLite in its implementation of [sqlite3_malloc()],
1983 ** but not overhead added by the any underlying system library
1984 ** routines that [sqlite3_malloc()] may call.
1986 ** {H17375} The memory high-water mark is reset to the current value of
1987 ** [sqlite3_memory_used()] if and only if the parameter to
1988 ** [sqlite3_memory_highwater()] is true. The value returned
1989 ** by [sqlite3_memory_highwater(1)] is the high-water mark
1990 ** prior to the reset.
1992 sqlite3_int64 sqlite3_memory_used(void);
1993 sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
1996 ** CAPI3REF: Pseudo-Random Number Generator {H17390} <S20000>
1998 ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
1999 ** select random ROWIDs when inserting new records into a table that
2000 ** already uses the largest possible ROWID. The PRNG is also used for
2001 ** the build-in random() and randomblob() SQL functions. This interface allows
2002 ** applications to access the same PRNG for other purposes.
2004 ** A call to this routine stores N bytes of randomness into buffer P.
2006 ** The first time this routine is invoked (either internally or by
2007 ** the application) the PRNG is seeded using randomness obtained
2008 ** from the xRandomness method of the default [sqlite3_vfs] object.
2009 ** On all subsequent invocations, the pseudo-randomness is generated
2010 ** internally and without recourse to the [sqlite3_vfs] xRandomness
2015 ** {H17392} The [sqlite3_randomness(N,P)] interface writes N bytes of
2016 ** high-quality pseudo-randomness into buffer P.
2018 void sqlite3_randomness(int N, void *P);
2021 ** CAPI3REF: Compile-Time Authorization Callbacks {H12500} <S70100>
2023 ** This routine registers a authorizer callback with a particular
2024 ** [database connection], supplied in the first argument.
2025 ** The authorizer callback is invoked as SQL statements are being compiled
2026 ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
2027 ** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. At various
2028 ** points during the compilation process, as logic is being created
2029 ** to perform various actions, the authorizer callback is invoked to
2030 ** see if those actions are allowed. The authorizer callback should
2031 ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
2032 ** specific action but allow the SQL statement to continue to be
2033 ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
2034 ** rejected with an error. If the authorizer callback returns
2035 ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
2036 ** then the [sqlite3_prepare_v2()] or equivalent call that triggered
2037 ** the authorizer will fail with an error message.
2039 ** When the callback returns [SQLITE_OK], that means the operation
2040 ** requested is ok. When the callback returns [SQLITE_DENY], the
2041 ** [sqlite3_prepare_v2()] or equivalent call that triggered the
2042 ** authorizer will fail with an error message explaining that
2043 ** access is denied. If the authorizer code is [SQLITE_READ]
2044 ** and the callback returns [SQLITE_IGNORE] then the
2045 ** [prepared statement] statement is constructed to substitute
2046 ** a NULL value in place of the table column that would have
2047 ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
2048 ** return can be used to deny an untrusted user access to individual
2049 ** columns of a table.
2051 ** The first parameter to the authorizer callback is a copy of the third
2052 ** parameter to the sqlite3_set_authorizer() interface. The second parameter
2053 ** to the callback is an integer [SQLITE_COPY | action code] that specifies
2054 ** the particular action to be authorized. The third through sixth parameters
2055 ** to the callback are zero-terminated strings that contain additional
2056 ** details about the action to be authorized.
2058 ** An authorizer is used when [sqlite3_prepare | preparing]
2059 ** SQL statements from an untrusted source, to ensure that the SQL statements
2060 ** do not try to access data they are not allowed to see, or that they do not
2061 ** try to execute malicious statements that damage the database. For
2062 ** example, an application may allow a user to enter arbitrary
2063 ** SQL queries for evaluation by a database. But the application does
2064 ** not want the user to be able to make arbitrary changes to the
2065 ** database. An authorizer could then be put in place while the
2066 ** user-entered SQL is being [sqlite3_prepare | prepared] that
2067 ** disallows everything except [SELECT] statements.
2069 ** Applications that need to process SQL from untrusted sources
2070 ** might also consider lowering resource limits using [sqlite3_limit()]
2071 ** and limiting database size using the [max_page_count] [PRAGMA]
2072 ** in addition to using an authorizer.
2074 ** Only a single authorizer can be in place on a database connection
2075 ** at a time. Each call to sqlite3_set_authorizer overrides the
2076 ** previous call. Disable the authorizer by installing a NULL callback.
2077 ** The authorizer is disabled by default.
2079 ** Note that the authorizer callback is invoked only during
2080 ** [sqlite3_prepare()] or its variants. Authorization is not
2081 ** performed during statement evaluation in [sqlite3_step()].
2085 ** {H12501} The [sqlite3_set_authorizer(D,...)] interface registers a
2086 ** authorizer callback with database connection D.
2088 ** {H12502} The authorizer callback is invoked as SQL statements are
2091 ** {H12503} If the authorizer callback returns any value other than
2092 ** [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY], then
2093 ** the [sqlite3_prepare_v2()] or equivalent call that caused
2094 ** the authorizer callback to run shall fail with an
2095 ** [SQLITE_ERROR] error code and an appropriate error message.
2097 ** {H12504} When the authorizer callback returns [SQLITE_OK], the operation
2098 ** described is processed normally.
2100 ** {H12505} When the authorizer callback returns [SQLITE_DENY], the
2101 ** [sqlite3_prepare_v2()] or equivalent call that caused the
2102 ** authorizer callback to run shall fail
2103 ** with an [SQLITE_ERROR] error code and an error message
2104 ** explaining that access is denied.
2106 ** {H12506} If the authorizer code (the 2nd parameter to the authorizer
2107 ** callback) is [SQLITE_READ] and the authorizer callback returns
2108 ** [SQLITE_IGNORE], then the prepared statement is constructed to
2109 ** insert a NULL value in place of the table column that would have
2110 ** been read if [SQLITE_OK] had been returned.
2112 ** {H12507} If the authorizer code (the 2nd parameter to the authorizer
2113 ** callback) is anything other than [SQLITE_READ], then
2114 ** a return of [SQLITE_IGNORE] has the same effect as [SQLITE_DENY].
2116 ** {H12510} The first parameter to the authorizer callback is a copy of
2117 ** the third parameter to the [sqlite3_set_authorizer()] interface.
2119 ** {H12511} The second parameter to the callback is an integer
2120 ** [SQLITE_COPY | action code] that specifies the particular action
2121 ** to be authorized.
2123 ** {H12512} The third through sixth parameters to the callback are
2124 ** zero-terminated strings that contain
2125 ** additional details about the action to be authorized.
2127 ** {H12520} Each call to [sqlite3_set_authorizer()] overrides
2128 ** any previously installed authorizer.
2130 ** {H12521} A NULL authorizer means that no authorization
2131 ** callback is invoked.
2133 ** {H12522} The default authorizer is NULL.
2135 int sqlite3_set_authorizer(
2137 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
2142 ** CAPI3REF: Authorizer Return Codes {H12590} <H12500>
2144 ** The [sqlite3_set_authorizer | authorizer callback function] must
2145 ** return either [SQLITE_OK] or one of these two constants in order
2146 ** to signal SQLite whether or not the action is permitted. See the
2147 ** [sqlite3_set_authorizer | authorizer documentation] for additional
2150 #define SQLITE_DENY 1 /* Abort the SQL statement with an error */
2151 #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
2154 ** CAPI3REF: Authorizer Action Codes {H12550} <H12500>
2156 ** The [sqlite3_set_authorizer()] interface registers a callback function
2157 ** that is invoked to authorize certain SQL statement actions. The
2158 ** second parameter to the callback is an integer code that specifies
2159 ** what action is being authorized. These are the integer action codes that
2160 ** the authorizer callback may be passed.
2162 ** These action code values signify what kind of operation is to be
2163 ** authorized. The 3rd and 4th parameters to the authorization
2164 ** callback function will be parameters or NULL depending on which of these
2165 ** codes is used as the second parameter. The 5th parameter to the
2166 ** authorizer callback is the name of the database ("main", "temp",
2167 ** etc.) if applicable. The 6th parameter to the authorizer callback
2168 ** is the name of the inner-most trigger or view that is responsible for
2169 ** the access attempt or NULL if this access attempt is directly from
2170 ** top-level SQL code.
2174 ** {H12551} The second parameter to an
2175 ** [sqlite3_set_authorizer | authorizer callback] is always an integer
2176 ** [SQLITE_COPY | authorizer code] that specifies what action
2177 ** is being authorized.
2179 ** {H12552} The 3rd and 4th parameters to the
2180 ** [sqlite3_set_authorizer | authorization callback]
2181 ** will be parameters or NULL depending on which
2182 ** [SQLITE_COPY | authorizer code] is used as the second parameter.
2184 ** {H12553} The 5th parameter to the
2185 ** [sqlite3_set_authorizer | authorizer callback] is the name
2186 ** of the database (example: "main", "temp", etc.) if applicable.
2188 ** {H12554} The 6th parameter to the
2189 ** [sqlite3_set_authorizer | authorizer callback] is the name
2190 ** of the inner-most trigger or view that is responsible for
2191 ** the access attempt or NULL if this access attempt is directly from
2192 ** top-level SQL code.
2194 /******************************************* 3rd ************ 4th ***********/
2195 #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
2196 #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
2197 #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
2198 #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
2199 #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
2200 #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
2201 #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
2202 #define SQLITE_CREATE_VIEW 8 /* View Name NULL */
2203 #define SQLITE_DELETE 9 /* Table Name NULL */
2204 #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
2205 #define SQLITE_DROP_TABLE 11 /* Table Name NULL */
2206 #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
2207 #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
2208 #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
2209 #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
2210 #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
2211 #define SQLITE_DROP_VIEW 17 /* View Name NULL */
2212 #define SQLITE_INSERT 18 /* Table Name NULL */
2213 #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
2214 #define SQLITE_READ 20 /* Table Name Column Name */
2215 #define SQLITE_SELECT 21 /* NULL NULL */
2216 #define SQLITE_TRANSACTION 22 /* NULL NULL */
2217 #define SQLITE_UPDATE 23 /* Table Name Column Name */
2218 #define SQLITE_ATTACH 24 /* Filename NULL */
2219 #define SQLITE_DETACH 25 /* Database Name NULL */
2220 #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
2221 #define SQLITE_REINDEX 27 /* Index Name NULL */
2222 #define SQLITE_ANALYZE 28 /* Table Name NULL */
2223 #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
2224 #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
2225 #define SQLITE_FUNCTION 31 /* Function Name NULL */
2226 #define SQLITE_COPY 0 /* No longer used */
2229 ** CAPI3REF: Tracing And Profiling Functions {H12280} <S60400>
2232 ** These routines register callback functions that can be used for
2233 ** tracing and profiling the execution of SQL statements.
2235 ** The callback function registered by sqlite3_trace() is invoked at
2236 ** various times when an SQL statement is being run by [sqlite3_step()].
2237 ** The callback returns a UTF-8 rendering of the SQL statement text
2238 ** as the statement first begins executing. Additional callbacks occur
2239 ** as each triggered subprogram is entered. The callbacks for triggers
2240 ** contain a UTF-8 SQL comment that identifies the trigger.
2242 ** The callback function registered by sqlite3_profile() is invoked
2243 ** as each SQL statement finishes. The profile callback contains
2244 ** the original statement text and an estimate of wall-clock time
2245 ** of how long that statement took to run.
2249 ** {H12281} The callback function registered by [sqlite3_trace()] is
2250 ** whenever an SQL statement first begins to execute and
2251 ** whenever a trigger subprogram first begins to run.
2253 ** {H12282} Each call to [sqlite3_trace()] overrides the previously
2254 ** registered trace callback.
2256 ** {H12283} A NULL trace callback disables tracing.
2258 ** {H12284} The first argument to the trace callback is a copy of
2259 ** the pointer which was the 3rd argument to [sqlite3_trace()].
2261 ** {H12285} The second argument to the trace callback is a
2262 ** zero-terminated UTF-8 string containing the original text
2263 ** of the SQL statement as it was passed into [sqlite3_prepare_v2()]
2264 ** or the equivalent, or an SQL comment indicating the beginning
2265 ** of a trigger subprogram.
2267 ** {H12287} The callback function registered by [sqlite3_profile()] is invoked
2268 ** as each SQL statement finishes.
2270 ** {H12288} The first parameter to the profile callback is a copy of
2271 ** the 3rd parameter to [sqlite3_profile()].
2273 ** {H12289} The second parameter to the profile callback is a
2274 ** zero-terminated UTF-8 string that contains the complete text of
2275 ** the SQL statement as it was processed by [sqlite3_prepare_v2()]
2276 ** or the equivalent.
2278 ** {H12290} The third parameter to the profile callback is an estimate
2279 ** of the number of nanoseconds of wall-clock time required to
2280 ** run the SQL statement from start to finish.
2282 void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
2283 void *sqlite3_profile(sqlite3*,
2284 void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
2287 ** CAPI3REF: Query Progress Callbacks {H12910} <S60400>
2289 ** This routine configures a callback function - the
2290 ** progress callback - that is invoked periodically during long
2291 ** running calls to [sqlite3_exec()], [sqlite3_step()] and
2292 ** [sqlite3_get_table()]. An example use for this
2293 ** interface is to keep a GUI updated during a large query.
2295 ** If the progress callback returns non-zero, the operation is
2296 ** interrupted. This feature can be used to implement a
2297 ** "Cancel" button on a GUI dialog box.
2301 ** {H12911} The callback function registered by sqlite3_progress_handler()
2302 ** is invoked periodically during long running calls to
2303 ** [sqlite3_step()].
2305 ** {H12912} The progress callback is invoked once for every N virtual
2306 ** machine opcodes, where N is the second argument to
2307 ** the [sqlite3_progress_handler()] call that registered
2308 ** the callback. If N is less than 1, sqlite3_progress_handler()
2309 ** acts as if a NULL progress handler had been specified.
2311 ** {H12913} The progress callback itself is identified by the third
2312 ** argument to sqlite3_progress_handler().
2314 ** {H12914} The fourth argument to sqlite3_progress_handler() is a
2315 ** void pointer passed to the progress callback
2316 ** function each time it is invoked.
2318 ** {H12915} If a call to [sqlite3_step()] results in fewer than N opcodes
2319 ** being executed, then the progress callback is never invoked.
2321 ** {H12916} Every call to [sqlite3_progress_handler()]
2322 ** overwrites any previously registered progress handler.
2324 ** {H12917} If the progress handler callback is NULL then no progress
2325 ** handler is invoked.
2327 ** {H12918} If the progress callback returns a result other than 0, then
2328 ** the behavior is a if [sqlite3_interrupt()] had been called.
2331 void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
2334 ** CAPI3REF: Opening A New Database Connection {H12700} <S40200>
2336 ** These routines open an SQLite database file whose name is given by the
2337 ** filename argument. The filename argument is interpreted as UTF-8 for
2338 ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
2339 ** order for sqlite3_open16(). A [database connection] handle is usually
2340 ** returned in *ppDb, even if an error occurs. The only exception is that
2341 ** if SQLite is unable to allocate memory to hold the [sqlite3] object,
2342 ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
2343 ** object. If the database is opened (and/or created) successfully, then
2344 ** [SQLITE_OK] is returned. Otherwise an [error code] is returned. The
2345 ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
2346 ** an English language description of the error.
2348 ** The default encoding for the database will be UTF-8 if
2349 ** sqlite3_open() or sqlite3_open_v2() is called and
2350 ** UTF-16 in the native byte order if sqlite3_open16() is used.
2352 ** Whether or not an error occurs when it is opened, resources
2353 ** associated with the [database connection] handle should be released by
2354 ** passing it to [sqlite3_close()] when it is no longer required.
2356 ** The sqlite3_open_v2() interface works like sqlite3_open()
2357 ** except that it accepts two additional parameters for additional control
2358 ** over the new database connection. The flags parameter can take one of
2359 ** the following three values, optionally combined with the
2360 ** [SQLITE_OPEN_NOMUTEX] flag:
2363 ** <dt>[SQLITE_OPEN_READONLY]</dt>
2364 ** <dd>The database is opened in read-only mode. If the database does not
2365 ** already exist, an error is returned.</dd>
2367 ** <dt>[SQLITE_OPEN_READWRITE]</dt>
2368 ** <dd>The database is opened for reading and writing if possible, or reading
2369 ** only if the file is write protected by the operating system. In either
2370 ** case the database must already exist, otherwise an error is returned.</dd>
2372 ** <dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
2373 ** <dd>The database is opened for reading and writing, and is creates it if
2374 ** it does not already exist. This is the behavior that is always used for
2375 ** sqlite3_open() and sqlite3_open16().</dd>
2378 ** If the 3rd parameter to sqlite3_open_v2() is not one of the
2379 ** combinations shown above or one of the combinations shown above combined
2380 ** with the [SQLITE_OPEN_NOMUTEX] flag, then the behavior is undefined.
2382 ** If the [SQLITE_OPEN_NOMUTEX] flag is set, then mutexes on the
2383 ** opened [database connection] are disabled and the appliation must
2384 ** insure that access to the [database connection] and its associated
2385 ** [prepared statements] is serialized. The [SQLITE_OPEN_NOMUTEX] flag
2386 ** is the default behavior is SQLite is configured using the
2387 ** [SQLITE_CONFIG_MULTITHREAD] or [SQLITE_CONFIG_SINGLETHREAD] options
2388 ** to [sqlite3_config()]. The [SQLITE_OPEN_NOMUTEX] flag only makes a
2389 ** difference when SQLite is in its default [SQLITE_CONFIG_SERIALIZED] mode.
2391 ** If the filename is ":memory:", then a private, temporary in-memory database
2392 ** is created for the connection. This in-memory database will vanish when
2393 ** the database connection is closed. Future versions of SQLite might
2394 ** make use of additional special filenames that begin with the ":" character.
2395 ** It is recommended that when a database filename actually does begin with
2396 ** a ":" character you should prefix the filename with a pathname such as
2397 ** "./" to avoid ambiguity.
2399 ** If the filename is an empty string, then a private, temporary
2400 ** on-disk database will be created. This private database will be
2401 ** automatically deleted as soon as the database connection is closed.
2403 ** The fourth parameter to sqlite3_open_v2() is the name of the
2404 ** [sqlite3_vfs] object that defines the operating system interface that
2405 ** the new database connection should use. If the fourth parameter is
2406 ** a NULL pointer then the default [sqlite3_vfs] object is used.
2408 ** <b>Note to Windows users:</b> The encoding used for the filename argument
2409 ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
2410 ** codepage is currently defined. Filenames containing international
2411 ** characters must be converted to UTF-8 prior to passing them into
2412 ** sqlite3_open() or sqlite3_open_v2().
2416 ** {H12701} The [sqlite3_open()], [sqlite3_open16()], and
2417 ** [sqlite3_open_v2()] interfaces create a new
2418 ** [database connection] associated with
2419 ** the database file given in their first parameter.
2421 ** {H12702} The filename argument is interpreted as UTF-8
2422 ** for [sqlite3_open()] and [sqlite3_open_v2()] and as UTF-16
2423 ** in the native byte order for [sqlite3_open16()].
2425 ** {H12703} A successful invocation of [sqlite3_open()], [sqlite3_open16()],
2426 ** or [sqlite3_open_v2()] writes a pointer to a new
2427 ** [database connection] into *ppDb.
2429 ** {H12704} The [sqlite3_open()], [sqlite3_open16()], and
2430 ** [sqlite3_open_v2()] interfaces return [SQLITE_OK] upon success,
2431 ** or an appropriate [error code] on failure.
2433 ** {H12706} The default text encoding for a new database created using
2434 ** [sqlite3_open()] or [sqlite3_open_v2()] will be UTF-8.
2436 ** {H12707} The default text encoding for a new database created using
2437 ** [sqlite3_open16()] will be UTF-16.
2439 ** {H12709} The [sqlite3_open(F,D)] interface is equivalent to
2440 ** [sqlite3_open_v2(F,D,G,0)] where the G parameter is
2441 ** [SQLITE_OPEN_READWRITE]|[SQLITE_OPEN_CREATE].
2443 ** {H12711} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
2444 ** bit value [SQLITE_OPEN_READONLY] then the database is opened
2445 ** for reading only.
2447 ** {H12712} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
2448 ** bit value [SQLITE_OPEN_READWRITE] then the database is opened
2449 ** reading and writing if possible, or for reading only if the
2450 ** file is write protected by the operating system.
2452 ** {H12713} If the G parameter to [sqlite3_open(v2(F,D,G,V)] omits the
2453 ** bit value [SQLITE_OPEN_CREATE] and the database does not
2454 ** previously exist, an error is returned.
2456 ** {H12714} If the G parameter to [sqlite3_open(v2(F,D,G,V)] contains the
2457 ** bit value [SQLITE_OPEN_CREATE] and the database does not
2458 ** previously exist, then an attempt is made to create and
2459 ** initialize the database.
2461 ** {H12717} If the filename argument to [sqlite3_open()], [sqlite3_open16()],
2462 ** or [sqlite3_open_v2()] is ":memory:", then an private,
2463 ** ephemeral, in-memory database is created for the connection.
2464 ** <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required
2465 ** in sqlite3_open_v2()?</todo>
2467 ** {H12719} If the filename is NULL or an empty string, then a private,
2468 ** ephemeral on-disk database will be created.
2469 ** <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required
2470 ** in sqlite3_open_v2()?</todo>
2472 ** {H12721} The [database connection] created by [sqlite3_open_v2(F,D,G,V)]
2473 ** will use the [sqlite3_vfs] object identified by the V parameter,
2474 ** or the default [sqlite3_vfs] object if V is a NULL pointer.
2476 ** {H12723} Two [database connections] will share a common cache if both were
2477 ** opened with the same VFS while [shared cache mode] was enabled and
2478 ** if both filenames compare equal using memcmp() after having been
2479 ** processed by the [sqlite3_vfs | xFullPathname] method of the VFS.
2482 const char *filename, /* Database filename (UTF-8) */
2483 sqlite3 **ppDb /* OUT: SQLite db handle */
2486 const void *filename, /* Database filename (UTF-16) */
2487 sqlite3 **ppDb /* OUT: SQLite db handle */
2489 int sqlite3_open_v2(
2490 const char *filename, /* Database filename (UTF-8) */
2491 sqlite3 **ppDb, /* OUT: SQLite db handle */
2492 int flags, /* Flags */
2493 const char *zVfs /* Name of VFS module to use */
2497 ** CAPI3REF: Error Codes And Messages {H12800} <S60200>
2499 ** The sqlite3_errcode() interface returns the numeric [result code] or
2500 ** [extended result code] for the most recent failed sqlite3_* API call
2501 ** associated with a [database connection]. If a prior API call failed
2502 ** but the most recent API call succeeded, the return value from
2503 ** sqlite3_errcode() is undefined.
2505 ** The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
2506 ** text that describes the error, as either UTF-8 or UTF-16 respectively.
2507 ** Memory to hold the error message string is managed internally.
2508 ** The application does not need to worry about freeing the result.
2509 ** However, the error string might be overwritten or deallocated by
2510 ** subsequent calls to other SQLite interface functions.
2512 ** If an interface fails with SQLITE_MISUSE, that means the interface
2513 ** was invoked incorrectly by the application. In that case, the
2514 ** error code and message may or may not be set.
2518 ** {H12801} The [sqlite3_errcode(D)] interface returns the numeric
2519 ** [result code] or [extended result code] for the most recently
2520 ** failed interface call associated with the [database connection] D.
2522 ** {H12803} The [sqlite3_errmsg(D)] and [sqlite3_errmsg16(D)]
2523 ** interfaces return English-language text that describes
2524 ** the error in the mostly recently failed interface call,
2525 ** encoded as either UTF-8 or UTF-16 respectively.
2527 ** {H12807} The strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()]
2528 ** are valid until the next SQLite interface call.
2530 ** {H12808} Calls to API routines that do not return an error code
2531 ** (example: [sqlite3_data_count()]) do not
2532 ** change the error code or message returned by
2533 ** [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()].
2535 ** {H12809} Interfaces that are not associated with a specific
2536 ** [database connection] (examples:
2537 ** [sqlite3_mprintf()] or [sqlite3_enable_shared_cache()]
2538 ** do not change the values returned by
2539 ** [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()].
2541 int sqlite3_errcode(sqlite3 *db);
2542 const char *sqlite3_errmsg(sqlite3*);
2543 const void *sqlite3_errmsg16(sqlite3*);
2546 ** CAPI3REF: SQL Statement Object {H13000} <H13010>
2547 ** KEYWORDS: {prepared statement} {prepared statements}
2549 ** An instance of this object represents a single SQL statement.
2550 ** This object is variously known as a "prepared statement" or a
2551 ** "compiled SQL statement" or simply as a "statement".
2553 ** The life of a statement object goes something like this:
2556 ** <li> Create the object using [sqlite3_prepare_v2()] or a related
2558 ** <li> Bind values to [host parameters] using the sqlite3_bind_*()
2560 ** <li> Run the SQL by calling [sqlite3_step()] one or more times.
2561 ** <li> Reset the statement using [sqlite3_reset()] then go back
2562 ** to step 2. Do this zero or more times.
2563 ** <li> Destroy the object using [sqlite3_finalize()].
2566 ** Refer to documentation on individual methods above for additional
2569 typedef struct sqlite3_stmt sqlite3_stmt;
2572 ** CAPI3REF: Run-time Limits {H12760} <S20600>
2574 ** This interface allows the size of various constructs to be limited
2575 ** on a connection by connection basis. The first parameter is the
2576 ** [database connection] whose limit is to be set or queried. The
2577 ** second parameter is one of the [limit categories] that define a
2578 ** class of constructs to be size limited. The third parameter is the
2579 ** new limit for that construct. The function returns the old limit.
2581 ** If the new limit is a negative number, the limit is unchanged.
2582 ** For the limit category of SQLITE_LIMIT_XYZ there is a hard upper
2583 ** bound set by a compile-time C preprocessor macro named SQLITE_MAX_XYZ.
2584 ** (The "_LIMIT_" in the name is changed to "_MAX_".)
2585 ** Attempts to increase a limit above its hard upper bound are
2586 ** silently truncated to the hard upper limit.
2588 ** Run time limits are intended for use in applications that manage
2589 ** both their own internal database and also databases that are controlled
2590 ** by untrusted external sources. An example application might be a
2591 ** webbrowser that has its own databases for storing history and
2592 ** separate databases controlled by JavaScript applications downloaded
2593 ** off the Internet. The internal databases can be given the
2594 ** large, default limits. Databases managed by external sources can
2595 ** be given much smaller limits designed to prevent a denial of service
2596 ** attack. Developers might also want to use the [sqlite3_set_authorizer()]
2597 ** interface to further control untrusted SQL. The size of the database
2598 ** created by an untrusted script can be contained using the
2599 ** [max_page_count] [PRAGMA].
2601 ** New run-time limit categories may be added in future releases.
2605 ** {H12762} A successful call to [sqlite3_limit(D,C,V)] where V is
2606 ** positive changes the limit on the size of construct C in the
2607 ** [database connection] D to the lesser of V and the hard upper
2608 ** bound on the size of C that is set at compile-time.
2610 ** {H12766} A successful call to [sqlite3_limit(D,C,V)] where V is negative
2611 ** leaves the state of the [database connection] D unchanged.
2613 ** {H12769} A successful call to [sqlite3_limit(D,C,V)] returns the
2614 ** value of the limit on the size of construct C in the
2615 ** [database connection] D as it was prior to the call.
2617 int sqlite3_limit(sqlite3*, int id, int newVal);
2620 ** CAPI3REF: Run-Time Limit Categories {H12790} <H12760>
2621 ** KEYWORDS: {limit category} {limit categories}
2623 ** These constants define various aspects of a [database connection]
2624 ** that can be limited in size by calls to [sqlite3_limit()].
2625 ** The meanings of the various limits are as follows:
2628 ** <dt>SQLITE_LIMIT_LENGTH</dt>
2629 ** <dd>The maximum size of any string or BLOB or table row.<dd>
2631 ** <dt>SQLITE_LIMIT_SQL_LENGTH</dt>
2632 ** <dd>The maximum length of an SQL statement.</dd>
2634 ** <dt>SQLITE_LIMIT_COLUMN</dt>
2635 ** <dd>The maximum number of columns in a table definition or in the
2636 ** result set of a SELECT or the maximum number of columns in an index
2637 ** or in an ORDER BY or GROUP BY clause.</dd>
2639 ** <dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
2640 ** <dd>The maximum depth of the parse tree on any expression.</dd>
2642 ** <dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
2643 ** <dd>The maximum number of terms in a compound SELECT statement.</dd>
2645 ** <dt>SQLITE_LIMIT_VDBE_OP</dt>
2646 ** <dd>The maximum number of instructions in a virtual machine program
2647 ** used to implement an SQL statement.</dd>
2649 ** <dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
2650 ** <dd>The maximum number of arguments on a function.</dd>
2652 ** <dt>SQLITE_LIMIT_ATTACHED</dt>
2653 ** <dd>The maximum number of attached databases.</dd>
2655 ** <dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
2656 ** <dd>The maximum length of the pattern argument to the LIKE or
2657 ** GLOB operators.</dd>
2659 ** <dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
2660 ** <dd>The maximum number of variables in an SQL statement that can
2664 #define SQLITE_LIMIT_LENGTH 0
2665 #define SQLITE_LIMIT_SQL_LENGTH 1
2666 #define SQLITE_LIMIT_COLUMN 2
2667 #define SQLITE_LIMIT_EXPR_DEPTH 3
2668 #define SQLITE_LIMIT_COMPOUND_SELECT 4
2669 #define SQLITE_LIMIT_VDBE_OP 5
2670 #define SQLITE_LIMIT_FUNCTION_ARG 6
2671 #define SQLITE_LIMIT_ATTACHED 7
2672 #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
2673 #define SQLITE_LIMIT_VARIABLE_NUMBER 9
2676 ** CAPI3REF: Compiling An SQL Statement {H13010} <S10000>
2677 ** KEYWORDS: {SQL statement compiler}
2679 ** To execute an SQL query, it must first be compiled into a byte-code
2680 ** program using one of these routines.
2682 ** The first argument, "db", is a [database connection] obtained from a
2683 ** prior call to [sqlite3_open()], [sqlite3_open_v2()] or [sqlite3_open16()].
2685 ** The second argument, "zSql", is the statement to be compiled, encoded
2686 ** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
2687 ** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
2690 ** If the nByte argument is less than zero, then zSql is read up to the
2691 ** first zero terminator. If nByte is non-negative, then it is the maximum
2692 ** number of bytes read from zSql. When nByte is non-negative, the
2693 ** zSql string ends at either the first '\000' or '\u0000' character or
2694 ** the nByte-th byte, whichever comes first. If the caller knows
2695 ** that the supplied string is nul-terminated, then there is a small
2696 ** performance advantage to be gained by passing an nByte parameter that
2697 ** is equal to the number of bytes in the input string <i>including</i>
2698 ** the nul-terminator bytes.
2700 ** *pzTail is made to point to the first byte past the end of the
2701 ** first SQL statement in zSql. These routines only compile the first
2702 ** statement in zSql, so *pzTail is left pointing to what remains
2705 ** *ppStmt is left pointing to a compiled [prepared statement] that can be
2706 ** executed using [sqlite3_step()]. If there is an error, *ppStmt is set
2707 ** to NULL. If the input text contains no SQL (if the input is an empty
2708 ** string or a comment) then *ppStmt is set to NULL.
2709 ** {A13018} The calling procedure is responsible for deleting the compiled
2710 ** SQL statement using [sqlite3_finalize()] after it has finished with it.
2712 ** On success, [SQLITE_OK] is returned, otherwise an [error code] is returned.
2714 ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
2715 ** recommended for all new programs. The two older interfaces are retained
2716 ** for backwards compatibility, but their use is discouraged.
2717 ** In the "v2" interfaces, the prepared statement
2718 ** that is returned (the [sqlite3_stmt] object) contains a copy of the
2719 ** original SQL text. This causes the [sqlite3_step()] interface to
2720 ** behave a differently in two ways:
2724 ** If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
2725 ** always used to do, [sqlite3_step()] will automatically recompile the SQL
2726 ** statement and try to run it again. If the schema has changed in
2727 ** a way that makes the statement no longer valid, [sqlite3_step()] will still
2728 ** return [SQLITE_SCHEMA]. But unlike the legacy behavior, [SQLITE_SCHEMA] is
2729 ** now a fatal error. Calling [sqlite3_prepare_v2()] again will not make the
2730 ** error go away. Note: use [sqlite3_errmsg()] to find the text
2731 ** of the parsing error that results in an [SQLITE_SCHEMA] return.
2735 ** When an error occurs, [sqlite3_step()] will return one of the detailed
2736 ** [error codes] or [extended error codes]. The legacy behavior was that
2737 ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
2738 ** and you would have to make a second call to [sqlite3_reset()] in order
2739 ** to find the underlying cause of the problem. With the "v2" prepare
2740 ** interfaces, the underlying reason for the error is returned immediately.
2746 ** {H13011} The [sqlite3_prepare(db,zSql,...)] and
2747 ** [sqlite3_prepare_v2(db,zSql,...)] interfaces interpret the
2748 ** text in their zSql parameter as UTF-8.
2750 ** {H13012} The [sqlite3_prepare16(db,zSql,...)] and
2751 ** [sqlite3_prepare16_v2(db,zSql,...)] interfaces interpret the
2752 ** text in their zSql parameter as UTF-16 in the native byte order.
2754 ** {H13013} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
2755 ** and its variants is less than zero, the SQL text is
2756 ** read from zSql is read up to the first zero terminator.
2758 ** {H13014} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
2759 ** and its variants is non-negative, then at most nBytes bytes of
2760 ** SQL text is read from zSql.
2762 ** {H13015} In [sqlite3_prepare_v2(db,zSql,N,P,pzTail)] and its variants
2763 ** if the zSql input text contains more than one SQL statement
2764 ** and pzTail is not NULL, then *pzTail is made to point to the
2765 ** first byte past the end of the first SQL statement in zSql.
2766 ** <todo>What does *pzTail point to if there is one statement?</todo>
2768 ** {H13016} A successful call to [sqlite3_prepare_v2(db,zSql,N,ppStmt,...)]
2769 ** or one of its variants writes into *ppStmt a pointer to a new
2770 ** [prepared statement] or a pointer to NULL if zSql contains
2771 ** nothing other than whitespace or comments.
2773 ** {H13019} The [sqlite3_prepare_v2()] interface and its variants return
2774 ** [SQLITE_OK] or an appropriate [error code] upon failure.
2776 ** {H13021} Before [sqlite3_prepare(db,zSql,nByte,ppStmt,pzTail)] or its
2777 ** variants returns an error (any value other than [SQLITE_OK]),
2778 ** they first set *ppStmt to NULL.
2780 int sqlite3_prepare(
2781 sqlite3 *db, /* Database handle */
2782 const char *zSql, /* SQL statement, UTF-8 encoded */
2783 int nByte, /* Maximum length of zSql in bytes. */
2784 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2785 const char **pzTail /* OUT: Pointer to unused portion of zSql */
2787 int sqlite3_prepare_v2(
2788 sqlite3 *db, /* Database handle */
2789 const char *zSql, /* SQL statement, UTF-8 encoded */
2790 int nByte, /* Maximum length of zSql in bytes. */
2791 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2792 const char **pzTail /* OUT: Pointer to unused portion of zSql */
2794 int sqlite3_prepare16(
2795 sqlite3 *db, /* Database handle */
2796 const void *zSql, /* SQL statement, UTF-16 encoded */
2797 int nByte, /* Maximum length of zSql in bytes. */
2798 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2799 const void **pzTail /* OUT: Pointer to unused portion of zSql */
2801 int sqlite3_prepare16_v2(
2802 sqlite3 *db, /* Database handle */
2803 const void *zSql, /* SQL statement, UTF-16 encoded */
2804 int nByte, /* Maximum length of zSql in bytes. */
2805 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2806 const void **pzTail /* OUT: Pointer to unused portion of zSql */
2810 ** CAPIREF: Retrieving Statement SQL {H13100} <H13000>
2812 ** This interface can be used to retrieve a saved copy of the original
2813 ** SQL text used to create a [prepared statement] if that statement was
2814 ** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
2818 ** {H13101} If the [prepared statement] passed as the argument to
2819 ** [sqlite3_sql()] was compiled using either [sqlite3_prepare_v2()] or
2820 ** [sqlite3_prepare16_v2()], then [sqlite3_sql()] returns
2821 ** a pointer to a zero-terminated string containing a UTF-8 rendering
2822 ** of the original SQL statement.
2824 ** {H13102} If the [prepared statement] passed as the argument to
2825 ** [sqlite3_sql()] was compiled using either [sqlite3_prepare()] or
2826 ** [sqlite3_prepare16()], then [sqlite3_sql()] returns a NULL pointer.
2828 ** {H13103} The string returned by [sqlite3_sql(S)] is valid until the
2829 ** [prepared statement] S is deleted using [sqlite3_finalize(S)].
2831 const char *sqlite3_sql(sqlite3_stmt *pStmt);
2834 ** CAPI3REF: Dynamically Typed Value Object {H15000} <S20200>
2835 ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
2837 ** SQLite uses the sqlite3_value object to represent all values
2838 ** that can be stored in a database table. SQLite uses dynamic typing
2839 ** for the values it stores. Values stored in sqlite3_value objects
2840 ** can be integers, floating point values, strings, BLOBs, or NULL.
2842 ** An sqlite3_value object may be either "protected" or "unprotected".
2843 ** Some interfaces require a protected sqlite3_value. Other interfaces
2844 ** will accept either a protected or an unprotected sqlite3_value.
2845 ** Every interface that accepts sqlite3_value arguments specifies
2846 ** whether or not it requires a protected sqlite3_value.
2848 ** The terms "protected" and "unprotected" refer to whether or not
2849 ** a mutex is held. A internal mutex is held for a protected
2850 ** sqlite3_value object but no mutex is held for an unprotected
2851 ** sqlite3_value object. If SQLite is compiled to be single-threaded
2852 ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
2853 ** or if SQLite is run in one of reduced mutex modes
2854 ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
2855 ** then there is no distinction between protected and unprotected
2856 ** sqlite3_value objects and they can be used interchangeably. However,
2857 ** for maximum code portability it is recommended that applications
2858 ** still make the distinction between between protected and unprotected
2859 ** sqlite3_value objects even when not strictly required.
2861 ** The sqlite3_value objects that are passed as parameters into the
2862 ** implementation of [application-defined SQL functions] are protected.
2863 ** The sqlite3_value object returned by
2864 ** [sqlite3_column_value()] is unprotected.
2865 ** Unprotected sqlite3_value objects may only be used with
2866 ** [sqlite3_result_value()] and [sqlite3_bind_value()].
2867 ** The [sqlite3_value_blob | sqlite3_value_type()] family of
2868 ** interfaces require protected sqlite3_value objects.
2870 typedef struct Mem sqlite3_value;
2873 ** CAPI3REF: SQL Function Context Object {H16001} <S20200>
2875 ** The context in which an SQL function executes is stored in an
2876 ** sqlite3_context object. A pointer to an sqlite3_context object
2877 ** is always first parameter to [application-defined SQL functions].
2878 ** The application-defined SQL function implementation will pass this
2879 ** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
2880 ** [sqlite3_aggregate_context()], [sqlite3_user_data()],
2881 ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
2882 ** and/or [sqlite3_set_auxdata()].
2884 typedef struct sqlite3_context sqlite3_context;
2887 ** CAPI3REF: Binding Values To Prepared Statements {H13500} <S70300>
2888 ** KEYWORDS: {host parameter} {host parameters} {host parameter name}
2889 ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
2891 ** In the SQL strings input to [sqlite3_prepare_v2()] and its variants,
2892 ** literals may be replaced by a parameter in one of these forms:
2902 ** In the parameter forms shown above NNN is an integer literal,
2903 ** and VVV is an alpha-numeric parameter name. The values of these
2904 ** parameters (also called "host parameter names" or "SQL parameters")
2905 ** can be set using the sqlite3_bind_*() routines defined here.
2907 ** The first argument to the sqlite3_bind_*() routines is always
2908 ** a pointer to the [sqlite3_stmt] object returned from
2909 ** [sqlite3_prepare_v2()] or its variants.
2911 ** The second argument is the index of the SQL parameter to be set.
2912 ** The leftmost SQL parameter has an index of 1. When the same named
2913 ** SQL parameter is used more than once, second and subsequent
2914 ** occurrences have the same index as the first occurrence.
2915 ** The index for named parameters can be looked up using the
2916 ** [sqlite3_bind_parameter_index()] API if desired. The index
2917 ** for "?NNN" parameters is the value of NNN.
2918 ** The NNN value must be between 1 and the [sqlite3_limit()]
2919 ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
2921 ** The third argument is the value to bind to the parameter.
2923 ** In those routines that have a fourth argument, its value is the
2924 ** number of bytes in the parameter. To be clear: the value is the
2925 ** number of <u>bytes</u> in the value, not the number of characters.
2926 ** If the fourth parameter is negative, the length of the string is
2927 ** the number of bytes up to the first zero terminator.
2929 ** The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
2930 ** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
2931 ** string after SQLite has finished with it. If the fifth argument is
2932 ** the special value [SQLITE_STATIC], then SQLite assumes that the
2933 ** information is in static, unmanaged space and does not need to be freed.
2934 ** If the fifth argument has the value [SQLITE_TRANSIENT], then
2935 ** SQLite makes its own private copy of the data immediately, before
2936 ** the sqlite3_bind_*() routine returns.
2938 ** The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
2939 ** is filled with zeroes. A zeroblob uses a fixed amount of memory
2940 ** (just an integer to hold its size) while it is being processed.
2941 ** Zeroblobs are intended to serve as placeholders for BLOBs whose
2942 ** content is later written using
2943 ** [sqlite3_blob_open | incremental BLOB I/O] routines.
2944 ** A negative value for the zeroblob results in a zero-length BLOB.
2946 ** The sqlite3_bind_*() routines must be called after
2947 ** [sqlite3_prepare_v2()] (and its variants) or [sqlite3_reset()] and
2948 ** before [sqlite3_step()].
2949 ** Bindings are not cleared by the [sqlite3_reset()] routine.
2950 ** Unbound parameters are interpreted as NULL.
2952 ** These routines return [SQLITE_OK] on success or an error code if
2953 ** anything goes wrong. [SQLITE_RANGE] is returned if the parameter
2954 ** index is out of range. [SQLITE_NOMEM] is returned if malloc() fails.
2955 ** [SQLITE_MISUSE] might be returned if these routines are called on a
2956 ** virtual machine that is the wrong state or which has already been finalized.
2957 ** Detection of misuse is unreliable. Applications should not depend
2958 ** on SQLITE_MISUSE returns. SQLITE_MISUSE is intended to indicate a
2959 ** a logic error in the application. Future versions of SQLite might
2960 ** panic rather than return SQLITE_MISUSE.
2962 ** See also: [sqlite3_bind_parameter_count()],
2963 ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
2967 ** {H13506} The [SQL statement compiler] recognizes tokens of the forms
2968 ** "?", "?NNN", "$VVV", ":VVV", and "@VVV" as SQL parameters,
2969 ** where NNN is any sequence of one or more digits
2970 ** and where VVV is any sequence of one or more alphanumeric
2971 ** characters or "::" optionally followed by a string containing
2972 ** no spaces and contained within parentheses.
2974 ** {H13509} The initial value of an SQL parameter is NULL.
2976 ** {H13512} The index of an "?" SQL parameter is one larger than the
2977 ** largest index of SQL parameter to the left, or 1 if
2978 ** the "?" is the leftmost SQL parameter.
2980 ** {H13515} The index of an "?NNN" SQL parameter is the integer NNN.
2982 ** {H13518} The index of an ":VVV", "$VVV", or "@VVV" SQL parameter is
2983 ** the same as the index of leftmost occurrences of the same
2984 ** parameter, or one more than the largest index over all
2985 ** parameters to the left if this is the first occurrence
2986 ** of this parameter, or 1 if this is the leftmost parameter.
2988 ** {H13521} The [SQL statement compiler] fails with an [SQLITE_RANGE]
2989 ** error if the index of an SQL parameter is less than 1
2990 ** or greater than the compile-time SQLITE_MAX_VARIABLE_NUMBER
2993 ** {H13524} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,V,...)]
2994 ** associate the value V with all SQL parameters having an
2995 ** index of N in the [prepared statement] S.
2997 ** {H13527} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,...)]
2998 ** override prior calls with the same values of S and N.
3000 ** {H13530} Bindings established by [sqlite3_bind_text | sqlite3_bind(S,...)]
3001 ** persist across calls to [sqlite3_reset(S)].
3003 ** {H13533} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
3004 ** [sqlite3_bind_text(S,N,V,L,D)], or
3005 ** [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds the first L
3006 ** bytes of the BLOB or string pointed to by V, when L
3009 ** {H13536} In calls to [sqlite3_bind_text(S,N,V,L,D)] or
3010 ** [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds characters
3011 ** from V through the first zero character when L is negative.
3013 ** {H13539} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
3014 ** [sqlite3_bind_text(S,N,V,L,D)], or
3015 ** [sqlite3_bind_text16(S,N,V,L,D)] when D is the special
3016 ** constant [SQLITE_STATIC], SQLite assumes that the value V
3017 ** is held in static unmanaged space that will not change
3018 ** during the lifetime of the binding.
3020 ** {H13542} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
3021 ** [sqlite3_bind_text(S,N,V,L,D)], or
3022 ** [sqlite3_bind_text16(S,N,V,L,D)] when D is the special
3023 ** constant [SQLITE_TRANSIENT], the routine makes a
3024 ** private copy of the value V before it returns.
3026 ** {H13545} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
3027 ** [sqlite3_bind_text(S,N,V,L,D)], or
3028 ** [sqlite3_bind_text16(S,N,V,L,D)] when D is a pointer to
3029 ** a function, SQLite invokes that function to destroy the
3030 ** value V after it has finished using the value V.
3032 ** {H13548} In calls to [sqlite3_bind_zeroblob(S,N,V,L)] the value bound
3033 ** is a BLOB of L bytes, or a zero-length BLOB if L is negative.
3035 ** {H13551} In calls to [sqlite3_bind_value(S,N,V)] the V argument may
3036 ** be either a [protected sqlite3_value] object or an
3037 ** [unprotected sqlite3_value] object.
3039 int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
3040 int sqlite3_bind_double(sqlite3_stmt*, int, double);
3041 int sqlite3_bind_int(sqlite3_stmt*, int, int);
3042 int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
3043 int sqlite3_bind_null(sqlite3_stmt*, int);
3044 int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
3045 int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
3046 int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
3047 int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
3050 ** CAPI3REF: Number Of SQL Parameters {H13600} <S70300>
3052 ** This routine can be used to find the number of [SQL parameters]
3053 ** in a [prepared statement]. SQL parameters are tokens of the
3054 ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
3055 ** placeholders for values that are [sqlite3_bind_blob | bound]
3056 ** to the parameters at a later time.
3058 ** This routine actually returns the index of the largest (rightmost)
3059 ** parameter. For all forms except ?NNN, this will correspond to the
3060 ** number of unique parameters. If parameters of the ?NNN are used,
3061 ** there may be gaps in the list.
3063 ** See also: [sqlite3_bind_blob|sqlite3_bind()],
3064 ** [sqlite3_bind_parameter_name()], and
3065 ** [sqlite3_bind_parameter_index()].
3069 ** {H13601} The [sqlite3_bind_parameter_count(S)] interface returns
3070 ** the largest index of all SQL parameters in the
3071 ** [prepared statement] S, or 0 if S contains no SQL parameters.
3073 int sqlite3_bind_parameter_count(sqlite3_stmt*);
3076 ** CAPI3REF: Name Of A Host Parameter {H13620} <S70300>
3078 ** This routine returns a pointer to the name of the n-th
3079 ** [SQL parameter] in a [prepared statement].
3080 ** SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
3081 ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
3083 ** In other words, the initial ":" or "$" or "@" or "?"
3084 ** is included as part of the name.
3085 ** Parameters of the form "?" without a following integer have no name
3086 ** and are also referred to as "anonymous parameters".
3088 ** The first host parameter has an index of 1, not 0.
3090 ** If the value n is out of range or if the n-th parameter is
3091 ** nameless, then NULL is returned. The returned string is
3092 ** always in UTF-8 encoding even if the named parameter was
3093 ** originally specified as UTF-16 in [sqlite3_prepare16()] or
3094 ** [sqlite3_prepare16_v2()].
3096 ** See also: [sqlite3_bind_blob|sqlite3_bind()],
3097 ** [sqlite3_bind_parameter_count()], and
3098 ** [sqlite3_bind_parameter_index()].
3102 ** {H13621} The [sqlite3_bind_parameter_name(S,N)] interface returns
3103 ** a UTF-8 rendering of the name of the SQL parameter in
3104 ** the [prepared statement] S having index N, or
3105 ** NULL if there is no SQL parameter with index N or if the
3106 ** parameter with index N is an anonymous parameter "?".
3108 const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
3111 ** CAPI3REF: Index Of A Parameter With A Given Name {H13640} <S70300>
3113 ** Return the index of an SQL parameter given its name. The
3114 ** index value returned is suitable for use as the second
3115 ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. A zero
3116 ** is returned if no matching parameter is found. The parameter
3117 ** name must be given in UTF-8 even if the original statement
3118 ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
3120 ** See also: [sqlite3_bind_blob|sqlite3_bind()],
3121 ** [sqlite3_bind_parameter_count()], and
3122 ** [sqlite3_bind_parameter_index()].
3126 ** {H13641} The [sqlite3_bind_parameter_index(S,N)] interface returns
3127 ** the index of SQL parameter in the [prepared statement]
3128 ** S whose name matches the UTF-8 string N, or 0 if there is
3131 int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
3134 ** CAPI3REF: Reset All Bindings On A Prepared Statement {H13660} <S70300>
3136 ** Contrary to the intuition of many, [sqlite3_reset()] does not reset
3137 ** the [sqlite3_bind_blob | bindings] on a [prepared statement].
3138 ** Use this routine to reset all host parameters to NULL.
3142 ** {H13661} The [sqlite3_clear_bindings(S)] interface resets all SQL
3143 ** parameter bindings in the [prepared statement] S back to NULL.
3145 int sqlite3_clear_bindings(sqlite3_stmt*);
3148 ** CAPI3REF: Number Of Columns In A Result Set {H13710} <S10700>
3150 ** Return the number of columns in the result set returned by the
3151 ** [prepared statement]. This routine returns 0 if pStmt is an SQL
3152 ** statement that does not return data (for example an [UPDATE]).
3156 ** {H13711} The [sqlite3_column_count(S)] interface returns the number of
3157 ** columns in the result set generated by the [prepared statement] S,
3158 ** or 0 if S does not generate a result set.
3160 int sqlite3_column_count(sqlite3_stmt *pStmt);
3163 ** CAPI3REF: Column Names In A Result Set {H13720} <S10700>
3165 ** These routines return the name assigned to a particular column
3166 ** in the result set of a [SELECT] statement. The sqlite3_column_name()
3167 ** interface returns a pointer to a zero-terminated UTF-8 string
3168 ** and sqlite3_column_name16() returns a pointer to a zero-terminated
3169 ** UTF-16 string. The first parameter is the [prepared statement]
3170 ** that implements the [SELECT] statement. The second parameter is the
3171 ** column number. The leftmost column is number 0.
3173 ** The returned string pointer is valid until either the [prepared statement]
3174 ** is destroyed by [sqlite3_finalize()] or until the next call to
3175 ** sqlite3_column_name() or sqlite3_column_name16() on the same column.
3177 ** If sqlite3_malloc() fails during the processing of either routine
3178 ** (for example during a conversion from UTF-8 to UTF-16) then a
3179 ** NULL pointer is returned.
3181 ** The name of a result column is the value of the "AS" clause for
3182 ** that column, if there is an AS clause. If there is no AS clause
3183 ** then the name of the column is unspecified and may change from
3184 ** one release of SQLite to the next.
3188 ** {H13721} A successful invocation of the [sqlite3_column_name(S,N)]
3189 ** interface returns the name of the Nth column (where 0 is
3190 ** the leftmost column) for the result set of the
3191 ** [prepared statement] S as a zero-terminated UTF-8 string.
3193 ** {H13723} A successful invocation of the [sqlite3_column_name16(S,N)]
3194 ** interface returns the name of the Nth column (where 0 is
3195 ** the leftmost column) for the result set of the
3196 ** [prepared statement] S as a zero-terminated UTF-16 string
3197 ** in the native byte order.
3199 ** {H13724} The [sqlite3_column_name()] and [sqlite3_column_name16()]
3200 ** interfaces return a NULL pointer if they are unable to
3201 ** allocate memory to hold their normal return strings.
3203 ** {H13725} If the N parameter to [sqlite3_column_name(S,N)] or
3204 ** [sqlite3_column_name16(S,N)] is out of range, then the
3205 ** interfaces return a NULL pointer.
3207 ** {H13726} The strings returned by [sqlite3_column_name(S,N)] and
3208 ** [sqlite3_column_name16(S,N)] are valid until the next
3209 ** call to either routine with the same S and N parameters
3210 ** or until [sqlite3_finalize(S)] is called.
3212 ** {H13727} When a result column of a [SELECT] statement contains
3213 ** an AS clause, the name of that column is the identifier
3214 ** to the right of the AS keyword.
3216 const char *sqlite3_column_name(sqlite3_stmt*, int N);
3217 const void *sqlite3_column_name16(sqlite3_stmt*, int N);
3220 ** CAPI3REF: Source Of Data In A Query Result {H13740} <S10700>
3222 ** These routines provide a means to determine what column of what
3223 ** table in which database a result of a [SELECT] statement comes from.
3224 ** The name of the database or table or column can be returned as
3225 ** either a UTF-8 or UTF-16 string. The _database_ routines return
3226 ** the database name, the _table_ routines return the table name, and
3227 ** the origin_ routines return the column name.
3228 ** The returned string is valid until the [prepared statement] is destroyed
3229 ** using [sqlite3_finalize()] or until the same information is requested
3230 ** again in a different encoding.
3232 ** The names returned are the original un-aliased names of the
3233 ** database, table, and column.
3235 ** The first argument to the following calls is a [prepared statement].
3236 ** These functions return information about the Nth column returned by
3237 ** the statement, where N is the second function argument.
3239 ** If the Nth column returned by the statement is an expression or
3240 ** subquery and is not a column value, then all of these functions return
3241 ** NULL. These routine might also return NULL if a memory allocation error
3242 ** occurs. Otherwise, they return the name of the attached database, table
3243 ** and column that query result column was extracted from.
3245 ** As with all other SQLite APIs, those postfixed with "16" return
3246 ** UTF-16 encoded strings, the other functions return UTF-8. {END}
3248 ** These APIs are only available if the library was compiled with the
3249 ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
3252 ** If two or more threads call one or more of these routines against the same
3253 ** prepared statement and column at the same time then the results are
3258 ** {H13741} The [sqlite3_column_database_name(S,N)] interface returns either
3259 ** the UTF-8 zero-terminated name of the database from which the
3260 ** Nth result column of the [prepared statement] S is extracted,
3261 ** or NULL if the Nth column of S is a general expression
3262 ** or if unable to allocate memory to store the name.
3264 ** {H13742} The [sqlite3_column_database_name16(S,N)] interface returns either
3265 ** the UTF-16 native byte order zero-terminated name of the database
3266 ** from which the Nth result column of the [prepared statement] S is
3267 ** extracted, or NULL if the Nth column of S is a general expression
3268 ** or if unable to allocate memory to store the name.
3270 ** {H13743} The [sqlite3_column_table_name(S,N)] interface returns either
3271 ** the UTF-8 zero-terminated name of the table from which the
3272 ** Nth result column of the [prepared statement] S is extracted,
3273 ** or NULL if the Nth column of S is a general expression
3274 ** or if unable to allocate memory to store the name.
3276 ** {H13744} The [sqlite3_column_table_name16(S,N)] interface returns either
3277 ** the UTF-16 native byte order zero-terminated name of the table
3278 ** from which the Nth result column of the [prepared statement] S is
3279 ** extracted, or NULL if the Nth column of S is a general expression
3280 ** or if unable to allocate memory to store the name.
3282 ** {H13745} The [sqlite3_column_origin_name(S,N)] interface returns either
3283 ** the UTF-8 zero-terminated name of the table column from which the
3284 ** Nth result column of the [prepared statement] S is extracted,
3285 ** or NULL if the Nth column of S is a general expression
3286 ** or if unable to allocate memory to store the name.
3288 ** {H13746} The [sqlite3_column_origin_name16(S,N)] interface returns either
3289 ** the UTF-16 native byte order zero-terminated name of the table
3290 ** column from which the Nth result column of the
3291 ** [prepared statement] S is extracted, or NULL if the Nth column
3292 ** of S is a general expression or if unable to allocate memory
3293 ** to store the name.
3295 ** {H13748} The return values from
3296 ** [sqlite3_column_database_name | column metadata interfaces]
3297 ** are valid for the lifetime of the [prepared statement]
3298 ** or until the encoding is changed by another metadata
3299 ** interface call for the same prepared statement and column.
3303 ** {A13751} If two or more threads call one or more
3304 ** [sqlite3_column_database_name | column metadata interfaces]
3305 ** for the same [prepared statement] and result column
3306 ** at the same time then the results are undefined.
3308 const char *sqlite3_column_database_name(sqlite3_stmt*,int);
3309 const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
3310 const char *sqlite3_column_table_name(sqlite3_stmt*,int);
3311 const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
3312 const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
3313 const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
3316 ** CAPI3REF: Declared Datatype Of A Query Result {H13760} <S10700>
3318 ** The first parameter is a [prepared statement].
3319 ** If this statement is a [SELECT] statement and the Nth column of the
3320 ** returned result set of that [SELECT] is a table column (not an
3321 ** expression or subquery) then the declared type of the table
3322 ** column is returned. If the Nth column of the result set is an
3323 ** expression or subquery, then a NULL pointer is returned.
3324 ** The returned string is always UTF-8 encoded. {END}
3326 ** For example, given the database schema:
3328 ** CREATE TABLE t1(c1 VARIANT);
3330 ** and the following statement to be compiled:
3332 ** SELECT c1 + 1, c1 FROM t1;
3334 ** this routine would return the string "VARIANT" for the second result
3335 ** column (i==1), and a NULL pointer for the first result column (i==0).
3337 ** SQLite uses dynamic run-time typing. So just because a column
3338 ** is declared to contain a particular type does not mean that the
3339 ** data stored in that column is of the declared type. SQLite is
3340 ** strongly typed, but the typing is dynamic not static. Type
3341 ** is associated with individual values, not with the containers
3342 ** used to hold those values.
3346 ** {H13761} A successful call to [sqlite3_column_decltype(S,N)] returns a
3347 ** zero-terminated UTF-8 string containing the declared datatype
3348 ** of the table column that appears as the Nth column (numbered
3349 ** from 0) of the result set to the [prepared statement] S.
3351 ** {H13762} A successful call to [sqlite3_column_decltype16(S,N)]
3352 ** returns a zero-terminated UTF-16 native byte order string
3353 ** containing the declared datatype of the table column that appears
3354 ** as the Nth column (numbered from 0) of the result set to the
3355 ** [prepared statement] S.
3357 ** {H13763} If N is less than 0 or N is greater than or equal to
3358 ** the number of columns in the [prepared statement] S,
3359 ** or if the Nth column of S is an expression or subquery rather
3360 ** than a table column, or if a memory allocation failure
3361 ** occurs during encoding conversions, then
3362 ** calls to [sqlite3_column_decltype(S,N)] or
3363 ** [sqlite3_column_decltype16(S,N)] return NULL.
3365 const char *sqlite3_column_decltype(sqlite3_stmt*,int);
3366 const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
3369 ** CAPI3REF: Evaluate An SQL Statement {H13200} <S10000>
3371 ** After a [prepared statement] has been prepared using either
3372 ** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
3373 ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
3374 ** must be called one or more times to evaluate the statement.
3376 ** The details of the behavior of the sqlite3_step() interface depend
3377 ** on whether the statement was prepared using the newer "v2" interface
3378 ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
3379 ** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
3380 ** new "v2" interface is recommended for new applications but the legacy
3381 ** interface will continue to be supported.
3383 ** In the legacy interface, the return value will be either [SQLITE_BUSY],
3384 ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
3385 ** With the "v2" interface, any of the other [result codes] or
3386 ** [extended result codes] might be returned as well.
3388 ** [SQLITE_BUSY] means that the database engine was unable to acquire the
3389 ** database locks it needs to do its job. If the statement is a [COMMIT]
3390 ** or occurs outside of an explicit transaction, then you can retry the
3391 ** statement. If the statement is not a [COMMIT] and occurs within a
3392 ** explicit transaction then you should rollback the transaction before
3395 ** [SQLITE_DONE] means that the statement has finished executing
3396 ** successfully. sqlite3_step() should not be called again on this virtual
3397 ** machine without first calling [sqlite3_reset()] to reset the virtual
3398 ** machine back to its initial state.
3400 ** If the SQL statement being executed returns any data, then [SQLITE_ROW]
3401 ** is returned each time a new row of data is ready for processing by the
3402 ** caller. The values may be accessed using the [column access functions].
3403 ** sqlite3_step() is called again to retrieve the next row of data.
3405 ** [SQLITE_ERROR] means that a run-time error (such as a constraint
3406 ** violation) has occurred. sqlite3_step() should not be called again on
3407 ** the VM. More information may be found by calling [sqlite3_errmsg()].
3408 ** With the legacy interface, a more specific error code (for example,
3409 ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
3410 ** can be obtained by calling [sqlite3_reset()] on the
3411 ** [prepared statement]. In the "v2" interface,
3412 ** the more specific error code is returned directly by sqlite3_step().
3414 ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
3415 ** Perhaps it was called on a [prepared statement] that has
3416 ** already been [sqlite3_finalize | finalized] or on one that had
3417 ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
3418 ** be the case that the same database connection is being used by two or
3419 ** more threads at the same moment in time.
3421 ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
3422 ** API always returns a generic error code, [SQLITE_ERROR], following any
3423 ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
3424 ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
3425 ** specific [error codes] that better describes the error.
3426 ** We admit that this is a goofy design. The problem has been fixed
3427 ** with the "v2" interface. If you prepare all of your SQL statements
3428 ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
3429 ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
3430 ** then the more specific [error codes] are returned directly
3431 ** by sqlite3_step(). The use of the "v2" interface is recommended.
3435 ** {H13202} If the [prepared statement] S is ready to be run, then
3436 ** [sqlite3_step(S)] advances that prepared statement until
3437 ** completion or until it is ready to return another row of the
3438 ** result set, or until an [sqlite3_interrupt | interrupt]
3439 ** or a run-time error occurs.
3441 ** {H15304} When a call to [sqlite3_step(S)] causes the [prepared statement]
3442 ** S to run to completion, the function returns [SQLITE_DONE].
3444 ** {H15306} When a call to [sqlite3_step(S)] stops because it is ready to
3445 ** return another row of the result set, it returns [SQLITE_ROW].
3447 ** {H15308} If a call to [sqlite3_step(S)] encounters an
3448 ** [sqlite3_interrupt | interrupt] or a run-time error,
3449 ** it returns an appropriate error code that is not one of
3450 ** [SQLITE_OK], [SQLITE_ROW], or [SQLITE_DONE].
3452 ** {H15310} If an [sqlite3_interrupt | interrupt] or a run-time error
3453 ** occurs during a call to [sqlite3_step(S)]
3454 ** for a [prepared statement] S created using
3455 ** legacy interfaces [sqlite3_prepare()] or
3456 ** [sqlite3_prepare16()], then the function returns either
3457 ** [SQLITE_ERROR], [SQLITE_BUSY], or [SQLITE_MISUSE].
3459 int sqlite3_step(sqlite3_stmt*);
3462 ** CAPI3REF: Number of columns in a result set {H13770} <S10700>
3464 ** Returns the number of values in the current row of the result set.
3468 ** {H13771} After a call to [sqlite3_step(S)] that returns [SQLITE_ROW],
3469 ** the [sqlite3_data_count(S)] routine will return the same value
3470 ** as the [sqlite3_column_count(S)] function.
3472 ** {H13772} After [sqlite3_step(S)] has returned any value other than
3473 ** [SQLITE_ROW] or before [sqlite3_step(S)] has been called on the
3474 ** [prepared statement] for the first time since it was
3475 ** [sqlite3_prepare | prepared] or [sqlite3_reset | reset],
3476 ** the [sqlite3_data_count(S)] routine returns zero.
3478 int sqlite3_data_count(sqlite3_stmt *pStmt);
3481 ** CAPI3REF: Fundamental Datatypes {H10265} <S10110><S10120>
3482 ** KEYWORDS: SQLITE_TEXT
3484 ** {H10266} Every value in SQLite has one of five fundamental datatypes:
3487 ** <li> 64-bit signed integer
3488 ** <li> 64-bit IEEE floating point number
3494 ** These constants are codes for each of those types.
3496 ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
3497 ** for a completely different meaning. Software that links against both
3498 ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
3501 #define SQLITE_INTEGER 1
3502 #define SQLITE_FLOAT 2
3503 #define SQLITE_BLOB 4
3504 #define SQLITE_NULL 5
3508 # define SQLITE_TEXT 3
3510 #define SQLITE3_TEXT 3
3513 ** CAPI3REF: Result Values From A Query {H13800} <S10700>
3514 ** KEYWORDS: {column access functions}
3516 ** These routines form the "result set query" interface.
3518 ** These routines return information about a single column of the current
3519 ** result row of a query. In every case the first argument is a pointer
3520 ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
3521 ** that was returned from [sqlite3_prepare_v2()] or one of its variants)
3522 ** and the second argument is the index of the column for which information
3523 ** should be returned. The leftmost column of the result set has the index 0.
3525 ** If the SQL statement does not currently point to a valid row, or if the
3526 ** column index is out of range, the result is undefined.
3527 ** These routines may only be called when the most recent call to
3528 ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
3529 ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
3530 ** If any of these routines are called after [sqlite3_reset()] or
3531 ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
3532 ** something other than [SQLITE_ROW], the results are undefined.
3533 ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
3534 ** are called from a different thread while any of these routines
3535 ** are pending, then the results are undefined.
3537 ** The sqlite3_column_type() routine returns the
3538 ** [SQLITE_INTEGER | datatype code] for the initial data type
3539 ** of the result column. The returned value is one of [SQLITE_INTEGER],
3540 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
3541 ** returned by sqlite3_column_type() is only meaningful if no type
3542 ** conversions have occurred as described below. After a type conversion,
3543 ** the value returned by sqlite3_column_type() is undefined. Future
3544 ** versions of SQLite may change the behavior of sqlite3_column_type()
3545 ** following a type conversion.
3547 ** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
3548 ** routine returns the number of bytes in that BLOB or string.
3549 ** If the result is a UTF-16 string, then sqlite3_column_bytes() converts
3550 ** the string to UTF-8 and then returns the number of bytes.
3551 ** If the result is a numeric value then sqlite3_column_bytes() uses
3552 ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
3553 ** the number of bytes in that string.
3554 ** The value returned does not include the zero terminator at the end
3555 ** of the string. For clarity: the value returned is the number of
3556 ** bytes in the string, not the number of characters.
3558 ** Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
3559 ** even empty strings, are always zero terminated. The return
3560 ** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary
3561 ** pointer, possibly even a NULL pointer.
3563 ** The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
3564 ** but leaves the result in UTF-16 in native byte order instead of UTF-8.
3565 ** The zero terminator is not included in this count.
3567 ** The object returned by [sqlite3_column_value()] is an
3568 ** [unprotected sqlite3_value] object. An unprotected sqlite3_value object
3569 ** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
3570 ** If the [unprotected sqlite3_value] object returned by
3571 ** [sqlite3_column_value()] is used in any other way, including calls
3572 ** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
3573 ** or [sqlite3_value_bytes()], then the behavior is undefined.
3575 ** These routines attempt to convert the value where appropriate. For
3576 ** example, if the internal representation is FLOAT and a text result
3577 ** is requested, [sqlite3_snprintf()] is used internally to perform the
3578 ** conversion automatically. The following table details the conversions
3579 ** that are applied:
3582 ** <table border="1">
3583 ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
3585 ** <tr><td> NULL <td> INTEGER <td> Result is 0
3586 ** <tr><td> NULL <td> FLOAT <td> Result is 0.0
3587 ** <tr><td> NULL <td> TEXT <td> Result is NULL pointer
3588 ** <tr><td> NULL <td> BLOB <td> Result is NULL pointer
3589 ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
3590 ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
3591 ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
3592 ** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer
3593 ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
3594 ** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT
3595 ** <tr><td> TEXT <td> INTEGER <td> Use atoi()
3596 ** <tr><td> TEXT <td> FLOAT <td> Use atof()
3597 ** <tr><td> TEXT <td> BLOB <td> No change
3598 ** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi()
3599 ** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof()
3600 ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
3604 ** The table above makes reference to standard C library functions atoi()
3605 ** and atof(). SQLite does not really use these functions. It has its
3606 ** own equivalent internal routines. The atoi() and atof() names are
3607 ** used in the table for brevity and because they are familiar to most
3610 ** Note that when type conversions occur, pointers returned by prior
3611 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
3612 ** sqlite3_column_text16() may be invalidated.
3613 ** Type conversions and pointer invalidations might occur
3614 ** in the following cases:
3617 ** <li> The initial content is a BLOB and sqlite3_column_text() or
3618 ** sqlite3_column_text16() is called. A zero-terminator might
3619 ** need to be added to the string.</li>
3620 ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
3621 ** sqlite3_column_text16() is called. The content must be converted
3623 ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
3624 ** sqlite3_column_text() is called. The content must be converted
3628 ** Conversions between UTF-16be and UTF-16le are always done in place and do
3629 ** not invalidate a prior pointer, though of course the content of the buffer
3630 ** that the prior pointer points to will have been modified. Other kinds
3631 ** of conversion are done in place when it is possible, but sometimes they
3632 ** are not possible and in those cases prior pointers are invalidated.
3634 ** The safest and easiest to remember policy is to invoke these routines
3635 ** in one of the following ways:
3638 ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
3639 ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
3640 ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
3643 ** In other words, you should call sqlite3_column_text(),
3644 ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
3645 ** into the desired format, then invoke sqlite3_column_bytes() or
3646 ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
3647 ** to sqlite3_column_text() or sqlite3_column_blob() with calls to
3648 ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
3649 ** with calls to sqlite3_column_bytes().
3651 ** The pointers returned are valid until a type conversion occurs as
3652 ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
3653 ** [sqlite3_finalize()] is called. The memory space used to hold strings
3654 ** and BLOBs is freed automatically. Do <b>not</b> pass the pointers returned
3655 ** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
3656 ** [sqlite3_free()].
3658 ** If a memory allocation error occurs during the evaluation of any
3659 ** of these routines, a default value is returned. The default value
3660 ** is either the integer 0, the floating point number 0.0, or a NULL
3661 ** pointer. Subsequent calls to [sqlite3_errcode()] will return
3666 ** {H13803} The [sqlite3_column_blob(S,N)] interface converts the
3667 ** Nth column in the current row of the result set for
3668 ** the [prepared statement] S into a BLOB and then returns a
3669 ** pointer to the converted value.
3671 ** {H13806} The [sqlite3_column_bytes(S,N)] interface returns the
3672 ** number of bytes in the BLOB or string (exclusive of the
3673 ** zero terminator on the string) that was returned by the
3674 ** most recent call to [sqlite3_column_blob(S,N)] or
3675 ** [sqlite3_column_text(S,N)].
3677 ** {H13809} The [sqlite3_column_bytes16(S,N)] interface returns the
3678 ** number of bytes in the string (exclusive of the
3679 ** zero terminator on the string) that was returned by the
3680 ** most recent call to [sqlite3_column_text16(S,N)].
3682 ** {H13812} The [sqlite3_column_double(S,N)] interface converts the
3683 ** Nth column in the current row of the result set for the
3684 ** [prepared statement] S into a floating point value and
3685 ** returns a copy of that value.
3687 ** {H13815} The [sqlite3_column_int(S,N)] interface converts the
3688 ** Nth column in the current row of the result set for the
3689 ** [prepared statement] S into a 64-bit signed integer and
3690 ** returns the lower 32 bits of that integer.
3692 ** {H13818} The [sqlite3_column_int64(S,N)] interface converts the
3693 ** Nth column in the current row of the result set for the
3694 ** [prepared statement] S into a 64-bit signed integer and
3695 ** returns a copy of that integer.
3697 ** {H13821} The [sqlite3_column_text(S,N)] interface converts the
3698 ** Nth column in the current row of the result set for
3699 ** the [prepared statement] S into a zero-terminated UTF-8
3700 ** string and returns a pointer to that string.
3702 ** {H13824} The [sqlite3_column_text16(S,N)] interface converts the
3703 ** Nth column in the current row of the result set for the
3704 ** [prepared statement] S into a zero-terminated 2-byte
3705 ** aligned UTF-16 native byte order string and returns
3706 ** a pointer to that string.
3708 ** {H13827} The [sqlite3_column_type(S,N)] interface returns
3709 ** one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT],
3710 ** [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for
3711 ** the Nth column in the current row of the result set for
3712 ** the [prepared statement] S.
3714 ** {H13830} The [sqlite3_column_value(S,N)] interface returns a
3715 ** pointer to an [unprotected sqlite3_value] object for the
3716 ** Nth column in the current row of the result set for
3717 ** the [prepared statement] S.
3719 const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
3720 int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
3721 int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
3722 double sqlite3_column_double(sqlite3_stmt*, int iCol);
3723 int sqlite3_column_int(sqlite3_stmt*, int iCol);
3724 sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
3725 const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
3726 const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
3727 int sqlite3_column_type(sqlite3_stmt*, int iCol);
3728 sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
3731 ** CAPI3REF: Destroy A Prepared Statement Object {H13300} <S70300><S30100>
3733 ** The sqlite3_finalize() function is called to delete a [prepared statement].
3734 ** If the statement was executed successfully or not executed at all, then
3735 ** SQLITE_OK is returned. If execution of the statement failed then an
3736 ** [error code] or [extended error code] is returned.
3738 ** This routine can be called at any point during the execution of the
3739 ** [prepared statement]. If the virtual machine has not
3740 ** completed execution when this routine is called, that is like
3741 ** encountering an error or an [sqlite3_interrupt | interrupt].
3742 ** Incomplete updates may be rolled back and transactions canceled,
3743 ** depending on the circumstances, and the
3744 ** [error code] returned will be [SQLITE_ABORT].
3748 ** {H11302} The [sqlite3_finalize(S)] interface destroys the
3749 ** [prepared statement] S and releases all
3750 ** memory and file resources held by that object.
3752 ** {H11304} If the most recent call to [sqlite3_step(S)] for the
3753 ** [prepared statement] S returned an error,
3754 ** then [sqlite3_finalize(S)] returns that same error.
3756 int sqlite3_finalize(sqlite3_stmt *pStmt);
3759 ** CAPI3REF: Reset A Prepared Statement Object {H13330} <S70300>
3761 ** The sqlite3_reset() function is called to reset a [prepared statement]
3762 ** object back to its initial state, ready to be re-executed.
3763 ** Any SQL statement variables that had values bound to them using
3764 ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
3765 ** Use [sqlite3_clear_bindings()] to reset the bindings.
3767 ** {H11332} The [sqlite3_reset(S)] interface resets the [prepared statement] S
3768 ** back to the beginning of its program.
3770 ** {H11334} If the most recent call to [sqlite3_step(S)] for the
3771 ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
3772 ** or if [sqlite3_step(S)] has never before been called on S,
3773 ** then [sqlite3_reset(S)] returns [SQLITE_OK].
3775 ** {H11336} If the most recent call to [sqlite3_step(S)] for the
3776 ** [prepared statement] S indicated an error, then
3777 ** [sqlite3_reset(S)] returns an appropriate [error code].
3779 ** {H11338} The [sqlite3_reset(S)] interface does not change the values
3780 ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
3782 int sqlite3_reset(sqlite3_stmt *pStmt);
3785 ** CAPI3REF: Create Or Redefine SQL Functions {H16100} <S20200>
3786 ** KEYWORDS: {function creation routines}
3787 ** KEYWORDS: {application-defined SQL function}
3788 ** KEYWORDS: {application-defined SQL functions}
3790 ** These two functions (collectively known as "function creation routines")
3791 ** are used to add SQL functions or aggregates or to redefine the behavior
3792 ** of existing SQL functions or aggregates. The only difference between the
3793 ** two is that the second parameter, the name of the (scalar) function or
3794 ** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16
3795 ** for sqlite3_create_function16().
3797 ** The first parameter is the [database connection] to which the SQL
3798 ** function is to be added. If a single program uses more than one database
3799 ** connection internally, then SQL functions must be added individually to
3800 ** each database connection.
3802 ** The second parameter is the name of the SQL function to be created or
3803 ** redefined. The length of the name is limited to 255 bytes, exclusive of
3804 ** the zero-terminator. Note that the name length limit is in bytes, not
3805 ** characters. Any attempt to create a function with a longer name
3806 ** will result in [SQLITE_ERROR] being returned.
3808 ** The third parameter is the number of arguments that the SQL function or
3809 ** aggregate takes. If this parameter is negative, then the SQL function or
3810 ** aggregate may take any number of arguments.
3812 ** The fourth parameter, eTextRep, specifies what
3813 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
3814 ** its parameters. Any SQL function implementation should be able to work
3815 ** work with UTF-8, UTF-16le, or UTF-16be. But some implementations may be
3816 ** more efficient with one encoding than another. It is allowed to
3817 ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
3818 ** times with the same function but with different values of eTextRep.
3819 ** When multiple implementations of the same function are available, SQLite
3820 ** will pick the one that involves the least amount of data conversion.
3821 ** If there is only a single implementation which does not care what text
3822 ** encoding is used, then the fourth argument should be [SQLITE_ANY].
3824 ** The fifth parameter is an arbitrary pointer. The implementation of the
3825 ** function can gain access to this pointer using [sqlite3_user_data()].
3827 ** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
3828 ** pointers to C-language functions that implement the SQL function or
3829 ** aggregate. A scalar SQL function requires an implementation of the xFunc
3830 ** callback only, NULL pointers should be passed as the xStep and xFinal
3831 ** parameters. An aggregate SQL function requires an implementation of xStep
3832 ** and xFinal and NULL should be passed for xFunc. To delete an existing
3833 ** SQL function or aggregate, pass NULL for all three function callbacks.
3835 ** It is permitted to register multiple implementations of the same
3836 ** functions with the same name but with either differing numbers of
3837 ** arguments or differing preferred text encodings. SQLite will use
3838 ** the implementation most closely matches the way in which the
3839 ** SQL function is used.
3843 ** {H16103} The [sqlite3_create_function16()] interface behaves exactly
3844 ** like [sqlite3_create_function()] in every way except that it
3845 ** interprets the zFunctionName argument as zero-terminated UTF-16
3846 ** native byte order instead of as zero-terminated UTF-8.
3848 ** {H16106} A successful invocation of
3849 ** the [sqlite3_create_function(D,X,N,E,...)] interface registers
3850 ** or replaces callback functions in the [database connection] D
3851 ** used to implement the SQL function named X with N parameters
3852 ** and having a preferred text encoding of E.
3854 ** {H16109} A successful call to [sqlite3_create_function(D,X,N,E,P,F,S,L)]
3855 ** replaces the P, F, S, and L values from any prior calls with
3856 ** the same D, X, N, and E values.
3858 ** {H16112} The [sqlite3_create_function(D,X,...)] interface fails with
3859 ** a return code of [SQLITE_ERROR] if the SQL function name X is
3860 ** longer than 255 bytes exclusive of the zero terminator.
3862 ** {H16118} Either F must be NULL and S and L are non-NULL or else F
3863 ** is non-NULL and S and L are NULL, otherwise
3864 ** [sqlite3_create_function(D,X,N,E,P,F,S,L)] returns [SQLITE_ERROR].
3866 ** {H16121} The [sqlite3_create_function(D,...)] interface fails with an
3867 ** error code of [SQLITE_BUSY] if there exist [prepared statements]
3868 ** associated with the [database connection] D.
3870 ** {H16124} The [sqlite3_create_function(D,X,N,...)] interface fails with an
3871 ** error code of [SQLITE_ERROR] if parameter N (specifying the number
3872 ** of arguments to the SQL function being registered) is less
3873 ** than -1 or greater than 127.
3875 ** {H16127} When N is non-negative, the [sqlite3_create_function(D,X,N,...)]
3876 ** interface causes callbacks to be invoked for the SQL function
3877 ** named X when the number of arguments to the SQL function is
3880 ** {H16130} When N is -1, the [sqlite3_create_function(D,X,N,...)]
3881 ** interface causes callbacks to be invoked for the SQL function
3882 ** named X with any number of arguments.
3884 ** {H16133} When calls to [sqlite3_create_function(D,X,N,...)]
3885 ** specify multiple implementations of the same function X
3886 ** and when one implementation has N>=0 and the other has N=(-1)
3887 ** the implementation with a non-zero N is preferred.
3889 ** {H16136} When calls to [sqlite3_create_function(D,X,N,E,...)]
3890 ** specify multiple implementations of the same function X with
3891 ** the same number of arguments N but with different
3892 ** encodings E, then the implementation where E matches the
3893 ** database encoding is preferred.
3895 ** {H16139} For an aggregate SQL function created using
3896 ** [sqlite3_create_function(D,X,N,E,P,0,S,L)] the finalizer
3897 ** function L will always be invoked exactly once if the
3898 ** step function S is called one or more times.
3900 ** {H16142} When SQLite invokes either the xFunc or xStep function of
3901 ** an application-defined SQL function or aggregate created
3902 ** by [sqlite3_create_function()] or [sqlite3_create_function16()],
3903 ** then the array of [sqlite3_value] objects passed as the
3904 ** third parameter are always [protected sqlite3_value] objects.
3906 int sqlite3_create_function(
3908 const char *zFunctionName,
3912 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
3913 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
3914 void (*xFinal)(sqlite3_context*)
3916 int sqlite3_create_function16(
3918 const void *zFunctionName,
3922 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
3923 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
3924 void (*xFinal)(sqlite3_context*)
3928 ** CAPI3REF: Text Encodings {H10267} <S50200> <H16100>
3930 ** These constant define integer codes that represent the various
3931 ** text encodings supported by SQLite.
3933 #define SQLITE_UTF8 1
3934 #define SQLITE_UTF16LE 2
3935 #define SQLITE_UTF16BE 3
3936 #define SQLITE_UTF16 4 /* Use native byte order */
3937 #define SQLITE_ANY 5 /* sqlite3_create_function only */
3938 #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
3941 ** CAPI3REF: Deprecated Functions
3944 ** These functions are [deprecated]. In order to maintain
3945 ** backwards compatibility with older code, these functions continue
3946 ** to be supported. However, new applications should avoid
3947 ** the use of these functions. To help encourage people to avoid
3948 ** using these functions, we are not going to tell you want they do.
3950 int sqlite3_aggregate_count(sqlite3_context*);
3951 int sqlite3_expired(sqlite3_stmt*);
3952 int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
3953 int sqlite3_global_recover(void);
3954 void sqlite3_thread_cleanup(void);
3955 int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
3958 ** CAPI3REF: Obtaining SQL Function Parameter Values {H15100} <S20200>
3960 ** The C-language implementation of SQL functions and aggregates uses
3961 ** this set of interface routines to access the parameter values on
3962 ** the function or aggregate.
3964 ** The xFunc (for scalar functions) or xStep (for aggregates) parameters
3965 ** to [sqlite3_create_function()] and [sqlite3_create_function16()]
3966 ** define callbacks that implement the SQL functions and aggregates.
3967 ** The 4th parameter to these callbacks is an array of pointers to
3968 ** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
3969 ** each parameter to the SQL function. These routines are used to
3970 ** extract values from the [sqlite3_value] objects.
3972 ** These routines work only with [protected sqlite3_value] objects.
3973 ** Any attempt to use these routines on an [unprotected sqlite3_value]
3974 ** object results in undefined behavior.
3976 ** These routines work just like the corresponding [column access functions]
3977 ** except that these routines take a single [protected sqlite3_value] object
3978 ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
3980 ** The sqlite3_value_text16() interface extracts a UTF-16 string
3981 ** in the native byte-order of the host machine. The
3982 ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
3983 ** extract UTF-16 strings as big-endian and little-endian respectively.
3985 ** The sqlite3_value_numeric_type() interface attempts to apply
3986 ** numeric affinity to the value. This means that an attempt is
3987 ** made to convert the value to an integer or floating point. If
3988 ** such a conversion is possible without loss of information (in other
3989 ** words, if the value is a string that looks like a number)
3990 ** then the conversion is performed. Otherwise no conversion occurs.
3991 ** The [SQLITE_INTEGER | datatype] after conversion is returned.
3993 ** Please pay particular attention to the fact that the pointer returned
3994 ** from [sqlite3_value_blob()], [sqlite3_value_text()], or
3995 ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
3996 ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
3997 ** or [sqlite3_value_text16()].
3999 ** These routines must be called from the same thread as
4000 ** the SQL function that supplied the [sqlite3_value*] parameters.
4004 ** {H15103} The [sqlite3_value_blob(V)] interface converts the
4005 ** [protected sqlite3_value] object V into a BLOB and then
4006 ** returns a pointer to the converted value.
4008 ** {H15106} The [sqlite3_value_bytes(V)] interface returns the
4009 ** number of bytes in the BLOB or string (exclusive of the
4010 ** zero terminator on the string) that was returned by the
4011 ** most recent call to [sqlite3_value_blob(V)] or
4012 ** [sqlite3_value_text(V)].
4014 ** {H15109} The [sqlite3_value_bytes16(V)] interface returns the
4015 ** number of bytes in the string (exclusive of the
4016 ** zero terminator on the string) that was returned by the
4017 ** most recent call to [sqlite3_value_text16(V)],
4018 ** [sqlite3_value_text16be(V)], or [sqlite3_value_text16le(V)].
4020 ** {H15112} The [sqlite3_value_double(V)] interface converts the
4021 ** [protected sqlite3_value] object V into a floating point value and
4022 ** returns a copy of that value.
4024 ** {H15115} The [sqlite3_value_int(V)] interface converts the
4025 ** [protected sqlite3_value] object V into a 64-bit signed integer and
4026 ** returns the lower 32 bits of that integer.
4028 ** {H15118} The [sqlite3_value_int64(V)] interface converts the
4029 ** [protected sqlite3_value] object V into a 64-bit signed integer and
4030 ** returns a copy of that integer.
4032 ** {H15121} The [sqlite3_value_text(V)] interface converts the
4033 ** [protected sqlite3_value] object V into a zero-terminated UTF-8
4034 ** string and returns a pointer to that string.
4036 ** {H15124} The [sqlite3_value_text16(V)] interface converts the
4037 ** [protected sqlite3_value] object V into a zero-terminated 2-byte
4038 ** aligned UTF-16 native byte order
4039 ** string and returns a pointer to that string.
4041 ** {H15127} The [sqlite3_value_text16be(V)] interface converts the
4042 ** [protected sqlite3_value] object V into a zero-terminated 2-byte
4043 ** aligned UTF-16 big-endian
4044 ** string and returns a pointer to that string.
4046 ** {H15130} The [sqlite3_value_text16le(V)] interface converts the
4047 ** [protected sqlite3_value] object V into a zero-terminated 2-byte
4048 ** aligned UTF-16 little-endian
4049 ** string and returns a pointer to that string.
4051 ** {H15133} The [sqlite3_value_type(V)] interface returns
4052 ** one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT],
4053 ** [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for
4054 ** the [sqlite3_value] object V.
4056 ** {H15136} The [sqlite3_value_numeric_type(V)] interface converts
4057 ** the [protected sqlite3_value] object V into either an integer or
4058 ** a floating point value if it can do so without loss of
4059 ** information, and returns one of [SQLITE_NULL],
4060 ** [SQLITE_INTEGER], [SQLITE_FLOAT], [SQLITE_TEXT], or
4061 ** [SQLITE_BLOB] as appropriate for the
4062 ** [protected sqlite3_value] object V after the conversion attempt.
4064 const void *sqlite3_value_blob(sqlite3_value*);
4065 int sqlite3_value_bytes(sqlite3_value*);
4066 int sqlite3_value_bytes16(sqlite3_value*);
4067 double sqlite3_value_double(sqlite3_value*);
4068 int sqlite3_value_int(sqlite3_value*);
4069 sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
4070 const unsigned char *sqlite3_value_text(sqlite3_value*);
4071 const void *sqlite3_value_text16(sqlite3_value*);
4072 const void *sqlite3_value_text16le(sqlite3_value*);
4073 const void *sqlite3_value_text16be(sqlite3_value*);
4074 int sqlite3_value_type(sqlite3_value*);
4075 int sqlite3_value_numeric_type(sqlite3_value*);
4078 ** CAPI3REF: Obtain Aggregate Function Context {H16210} <S20200>
4080 ** The implementation of aggregate SQL functions use this routine to allocate
4081 ** a structure for storing their state.
4083 ** The first time the sqlite3_aggregate_context() routine is called for a
4084 ** particular aggregate, SQLite allocates nBytes of memory, zeroes out that
4085 ** memory, and returns a pointer to it. On second and subsequent calls to
4086 ** sqlite3_aggregate_context() for the same aggregate function index,
4087 ** the same buffer is returned. The implementation of the aggregate can use
4088 ** the returned buffer to accumulate data.
4090 ** SQLite automatically frees the allocated buffer when the aggregate
4093 ** The first parameter should be a copy of the
4094 ** [sqlite3_context | SQL function context] that is the first parameter
4095 ** to the callback routine that implements the aggregate function.
4097 ** This routine must be called from the same thread in which
4098 ** the aggregate SQL function is running.
4102 ** {H16211} The first invocation of [sqlite3_aggregate_context(C,N)] for
4103 ** a particular instance of an aggregate function (for a particular
4104 ** context C) causes SQLite to allocate N bytes of memory,
4105 ** zero that memory, and return a pointer to the allocated memory.
4107 ** {H16213} If a memory allocation error occurs during
4108 ** [sqlite3_aggregate_context(C,N)] then the function returns 0.
4110 ** {H16215} Second and subsequent invocations of
4111 ** [sqlite3_aggregate_context(C,N)] for the same context pointer C
4112 ** ignore the N parameter and return a pointer to the same
4113 ** block of memory returned by the first invocation.
4115 ** {H16217} The memory allocated by [sqlite3_aggregate_context(C,N)] is
4116 ** automatically freed on the next call to [sqlite3_reset()]
4117 ** or [sqlite3_finalize()] for the [prepared statement] containing
4118 ** the aggregate function associated with context C.
4120 void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
4123 ** CAPI3REF: User Data For Functions {H16240} <S20200>
4125 ** The sqlite3_user_data() interface returns a copy of
4126 ** the pointer that was the pUserData parameter (the 5th parameter)
4127 ** of the [sqlite3_create_function()]
4128 ** and [sqlite3_create_function16()] routines that originally
4129 ** registered the application defined function. {END}
4131 ** This routine must be called from the same thread in which
4132 ** the application-defined function is running.
4136 ** {H16243} The [sqlite3_user_data(C)] interface returns a copy of the
4137 ** P pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)]
4138 ** or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that
4139 ** registered the SQL function associated with [sqlite3_context] C.
4141 void *sqlite3_user_data(sqlite3_context*);
4144 ** CAPI3REF: Database Connection For Functions {H16250} <S60600><S20200>
4146 ** The sqlite3_context_db_handle() interface returns a copy of
4147 ** the pointer to the [database connection] (the 1st parameter)
4148 ** of the [sqlite3_create_function()]
4149 ** and [sqlite3_create_function16()] routines that originally
4150 ** registered the application defined function.
4154 ** {H16253} The [sqlite3_context_db_handle(C)] interface returns a copy of the
4155 ** D pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)]
4156 ** or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that
4157 ** registered the SQL function associated with [sqlite3_context] C.
4159 sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
4162 ** CAPI3REF: Function Auxiliary Data {H16270} <S20200>
4164 ** The following two functions may be used by scalar SQL functions to
4165 ** associate metadata with argument values. If the same value is passed to
4166 ** multiple invocations of the same SQL function during query execution, under
4167 ** some circumstances the associated metadata may be preserved. This may
4168 ** be used, for example, to add a regular-expression matching scalar
4169 ** function. The compiled version of the regular expression is stored as
4170 ** metadata associated with the SQL value passed as the regular expression
4171 ** pattern. The compiled regular expression can be reused on multiple
4172 ** invocations of the same function so that the original pattern string
4173 ** does not need to be recompiled on each invocation.
4175 ** The sqlite3_get_auxdata() interface returns a pointer to the metadata
4176 ** associated by the sqlite3_set_auxdata() function with the Nth argument
4177 ** value to the application-defined function. If no metadata has been ever
4178 ** been set for the Nth argument of the function, or if the corresponding
4179 ** function parameter has changed since the meta-data was set,
4180 ** then sqlite3_get_auxdata() returns a NULL pointer.
4182 ** The sqlite3_set_auxdata() interface saves the metadata
4183 ** pointed to by its 3rd parameter as the metadata for the N-th
4184 ** argument of the application-defined function. Subsequent
4185 ** calls to sqlite3_get_auxdata() might return this data, if it has
4186 ** not been destroyed.
4187 ** If it is not NULL, SQLite will invoke the destructor
4188 ** function given by the 4th parameter to sqlite3_set_auxdata() on
4189 ** the metadata when the corresponding function parameter changes
4190 ** or when the SQL statement completes, whichever comes first.
4192 ** SQLite is free to call the destructor and drop metadata on any
4193 ** parameter of any function at any time. The only guarantee is that
4194 ** the destructor will be called before the metadata is dropped.
4196 ** In practice, metadata is preserved between function calls for
4197 ** expressions that are constant at compile time. This includes literal
4198 ** values and SQL variables.
4200 ** These routines must be called from the same thread in which
4201 ** the SQL function is running.
4205 ** {H16272} The [sqlite3_get_auxdata(C,N)] interface returns a pointer
4206 ** to metadata associated with the Nth parameter of the SQL function
4207 ** whose context is C, or NULL if there is no metadata associated
4208 ** with that parameter.
4210 ** {H16274} The [sqlite3_set_auxdata(C,N,P,D)] interface assigns a metadata
4211 ** pointer P to the Nth parameter of the SQL function with context C.
4213 ** {H16276} SQLite will invoke the destructor D with a single argument
4214 ** which is the metadata pointer P following a call to
4215 ** [sqlite3_set_auxdata(C,N,P,D)] when SQLite ceases to hold
4218 ** {H16277} SQLite ceases to hold metadata for an SQL function parameter
4219 ** when the value of that parameter changes.
4221 ** {H16278} When [sqlite3_set_auxdata(C,N,P,D)] is invoked, the destructor
4222 ** is called for any prior metadata associated with the same function
4223 ** context C and parameter N.
4225 ** {H16279} SQLite will call destructors for any metadata it is holding
4226 ** in a particular [prepared statement] S when either
4227 ** [sqlite3_reset(S)] or [sqlite3_finalize(S)] is called.
4229 void *sqlite3_get_auxdata(sqlite3_context*, int N);
4230 void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
4234 ** CAPI3REF: Constants Defining Special Destructor Behavior {H10280} <S30100>
4236 ** These are special values for the destructor that is passed in as the
4237 ** final argument to routines like [sqlite3_result_blob()]. If the destructor
4238 ** argument is SQLITE_STATIC, it means that the content pointer is constant
4239 ** and will never change. It does not need to be destroyed. The
4240 ** SQLITE_TRANSIENT value means that the content will likely change in
4241 ** the near future and that SQLite should make its own private copy of
4242 ** the content before returning.
4244 ** The typedef is necessary to work around problems in certain
4245 ** C++ compilers. See ticket #2191.
4247 typedef void (*sqlite3_destructor_type)(void*);
4248 #define SQLITE_STATIC ((sqlite3_destructor_type)0)
4249 #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
4252 ** CAPI3REF: Setting The Result Of An SQL Function {H16400} <S20200>
4254 ** These routines are used by the xFunc or xFinal callbacks that
4255 ** implement SQL functions and aggregates. See
4256 ** [sqlite3_create_function()] and [sqlite3_create_function16()]
4257 ** for additional information.
4259 ** These functions work very much like the [parameter binding] family of
4260 ** functions used to bind values to host parameters in prepared statements.
4261 ** Refer to the [SQL parameter] documentation for additional information.
4263 ** The sqlite3_result_blob() interface sets the result from
4264 ** an application-defined function to be the BLOB whose content is pointed
4265 ** to by the second parameter and which is N bytes long where N is the
4268 ** The sqlite3_result_zeroblob() interfaces set the result of
4269 ** the application-defined function to be a BLOB containing all zero
4270 ** bytes and N bytes in size, where N is the value of the 2nd parameter.
4272 ** The sqlite3_result_double() interface sets the result from
4273 ** an application-defined function to be a floating point value specified
4274 ** by its 2nd argument.
4276 ** The sqlite3_result_error() and sqlite3_result_error16() functions
4277 ** cause the implemented SQL function to throw an exception.
4278 ** SQLite uses the string pointed to by the
4279 ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
4280 ** as the text of an error message. SQLite interprets the error
4281 ** message string from sqlite3_result_error() as UTF-8. SQLite
4282 ** interprets the string from sqlite3_result_error16() as UTF-16 in native
4283 ** byte order. If the third parameter to sqlite3_result_error()
4284 ** or sqlite3_result_error16() is negative then SQLite takes as the error
4285 ** message all text up through the first zero character.
4286 ** If the third parameter to sqlite3_result_error() or
4287 ** sqlite3_result_error16() is non-negative then SQLite takes that many
4288 ** bytes (not characters) from the 2nd parameter as the error message.
4289 ** The sqlite3_result_error() and sqlite3_result_error16()
4290 ** routines make a private copy of the error message text before
4291 ** they return. Hence, the calling function can deallocate or
4292 ** modify the text after they return without harm.
4293 ** The sqlite3_result_error_code() function changes the error code
4294 ** returned by SQLite as a result of an error in a function. By default,
4295 ** the error code is SQLITE_ERROR. A subsequent call to sqlite3_result_error()
4296 ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
4298 ** The sqlite3_result_toobig() interface causes SQLite to throw an error
4299 ** indicating that a string or BLOB is to long to represent.
4301 ** The sqlite3_result_nomem() interface causes SQLite to throw an error
4302 ** indicating that a memory allocation failed.
4304 ** The sqlite3_result_int() interface sets the return value
4305 ** of the application-defined function to be the 32-bit signed integer
4306 ** value given in the 2nd argument.
4307 ** The sqlite3_result_int64() interface sets the return value
4308 ** of the application-defined function to be the 64-bit signed integer
4309 ** value given in the 2nd argument.
4311 ** The sqlite3_result_null() interface sets the return value
4312 ** of the application-defined function to be NULL.
4314 ** The sqlite3_result_text(), sqlite3_result_text16(),
4315 ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
4316 ** set the return value of the application-defined function to be
4317 ** a text string which is represented as UTF-8, UTF-16 native byte order,
4318 ** UTF-16 little endian, or UTF-16 big endian, respectively.
4319 ** SQLite takes the text result from the application from
4320 ** the 2nd parameter of the sqlite3_result_text* interfaces.
4321 ** If the 3rd parameter to the sqlite3_result_text* interfaces
4322 ** is negative, then SQLite takes result text from the 2nd parameter
4323 ** through the first zero character.
4324 ** If the 3rd parameter to the sqlite3_result_text* interfaces
4325 ** is non-negative, then as many bytes (not characters) of the text
4326 ** pointed to by the 2nd parameter are taken as the application-defined
4328 ** If the 4th parameter to the sqlite3_result_text* interfaces
4329 ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
4330 ** function as the destructor on the text or BLOB result when it has
4331 ** finished using that result.
4332 ** If the 4th parameter to the sqlite3_result_text* interfaces or
4333 ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
4334 ** assumes that the text or BLOB result is in constant space and does not
4335 ** copy the it or call a destructor when it has finished using that result.
4336 ** If the 4th parameter to the sqlite3_result_text* interfaces
4337 ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
4338 ** then SQLite makes a copy of the result into space obtained from
4339 ** from [sqlite3_malloc()] before it returns.
4341 ** The sqlite3_result_value() interface sets the result of
4342 ** the application-defined function to be a copy the
4343 ** [unprotected sqlite3_value] object specified by the 2nd parameter. The
4344 ** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
4345 ** so that the [sqlite3_value] specified in the parameter may change or
4346 ** be deallocated after sqlite3_result_value() returns without harm.
4347 ** A [protected sqlite3_value] object may always be used where an
4348 ** [unprotected sqlite3_value] object is required, so either
4349 ** kind of [sqlite3_value] object can be used with this interface.
4351 ** If these routines are called from within the different thread
4352 ** than the one containing the application-defined function that received
4353 ** the [sqlite3_context] pointer, the results are undefined.
4357 ** {H16403} The default return value from any SQL function is NULL.
4359 ** {H16406} The [sqlite3_result_blob(C,V,N,D)] interface changes the
4360 ** return value of function C to be a BLOB that is N bytes
4361 ** in length and with content pointed to by V.
4363 ** {H16409} The [sqlite3_result_double(C,V)] interface changes the
4364 ** return value of function C to be the floating point value V.
4366 ** {H16412} The [sqlite3_result_error(C,V,N)] interface changes the return
4367 ** value of function C to be an exception with error code
4368 ** [SQLITE_ERROR] and a UTF-8 error message copied from V up to the
4369 ** first zero byte or until N bytes are read if N is positive.
4371 ** {H16415} The [sqlite3_result_error16(C,V,N)] interface changes the return
4372 ** value of function C to be an exception with error code
4373 ** [SQLITE_ERROR] and a UTF-16 native byte order error message
4374 ** copied from V up to the first zero terminator or until N bytes
4375 ** are read if N is positive.
4377 ** {H16418} The [sqlite3_result_error_toobig(C)] interface changes the return
4378 ** value of the function C to be an exception with error code
4379 ** [SQLITE_TOOBIG] and an appropriate error message.
4381 ** {H16421} The [sqlite3_result_error_nomem(C)] interface changes the return
4382 ** value of the function C to be an exception with error code
4383 ** [SQLITE_NOMEM] and an appropriate error message.
4385 ** {H16424} The [sqlite3_result_error_code(C,E)] interface changes the return
4386 ** value of the function C to be an exception with error code E.
4387 ** The error message text is unchanged.
4389 ** {H16427} The [sqlite3_result_int(C,V)] interface changes the
4390 ** return value of function C to be the 32-bit integer value V.
4392 ** {H16430} The [sqlite3_result_int64(C,V)] interface changes the
4393 ** return value of function C to be the 64-bit integer value V.
4395 ** {H16433} The [sqlite3_result_null(C)] interface changes the
4396 ** return value of function C to be NULL.
4398 ** {H16436} The [sqlite3_result_text(C,V,N,D)] interface changes the
4399 ** return value of function C to be the UTF-8 string
4400 ** V up to the first zero if N is negative
4401 ** or the first N bytes of V if N is non-negative.
4403 ** {H16439} The [sqlite3_result_text16(C,V,N,D)] interface changes the
4404 ** return value of function C to be the UTF-16 native byte order
4405 ** string V up to the first zero if N is negative
4406 ** or the first N bytes of V if N is non-negative.
4408 ** {H16442} The [sqlite3_result_text16be(C,V,N,D)] interface changes the
4409 ** return value of function C to be the UTF-16 big-endian
4410 ** string V up to the first zero if N is negative
4411 ** or the first N bytes or V if N is non-negative.
4413 ** {H16445} The [sqlite3_result_text16le(C,V,N,D)] interface changes the
4414 ** return value of function C to be the UTF-16 little-endian
4415 ** string V up to the first zero if N is negative
4416 ** or the first N bytes of V if N is non-negative.
4418 ** {H16448} The [sqlite3_result_value(C,V)] interface changes the
4419 ** return value of function C to be the [unprotected sqlite3_value]
4422 ** {H16451} The [sqlite3_result_zeroblob(C,N)] interface changes the
4423 ** return value of function C to be an N-byte BLOB of all zeros.
4425 ** {H16454} The [sqlite3_result_error()] and [sqlite3_result_error16()]
4426 ** interfaces make a copy of their error message strings before
4429 ** {H16457} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
4430 ** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
4431 ** [sqlite3_result_text16be(C,V,N,D)], or
4432 ** [sqlite3_result_text16le(C,V,N,D)] is the constant [SQLITE_STATIC]
4433 ** then no destructor is ever called on the pointer V and SQLite
4434 ** assumes that V is immutable.
4436 ** {H16460} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
4437 ** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
4438 ** [sqlite3_result_text16be(C,V,N,D)], or
4439 ** [sqlite3_result_text16le(C,V,N,D)] is the constant
4440 ** [SQLITE_TRANSIENT] then the interfaces makes a copy of the
4441 ** content of V and retains the copy.
4443 ** {H16463} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
4444 ** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
4445 ** [sqlite3_result_text16be(C,V,N,D)], or
4446 ** [sqlite3_result_text16le(C,V,N,D)] is some value other than
4447 ** the constants [SQLITE_STATIC] and [SQLITE_TRANSIENT] then
4448 ** SQLite will invoke the destructor D with V as its only argument
4449 ** when it has finished with the V value.
4451 void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
4452 void sqlite3_result_double(sqlite3_context*, double);
4453 void sqlite3_result_error(sqlite3_context*, const char*, int);
4454 void sqlite3_result_error16(sqlite3_context*, const void*, int);
4455 void sqlite3_result_error_toobig(sqlite3_context*);
4456 void sqlite3_result_error_nomem(sqlite3_context*);
4457 void sqlite3_result_error_code(sqlite3_context*, int);
4458 void sqlite3_result_int(sqlite3_context*, int);
4459 void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
4460 void sqlite3_result_null(sqlite3_context*);
4461 void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
4462 void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
4463 void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
4464 void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
4465 void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
4466 void sqlite3_result_zeroblob(sqlite3_context*, int n);
4469 ** CAPI3REF: Define New Collating Sequences {H16600} <S20300>
4471 ** These functions are used to add new collation sequences to the
4472 ** [database connection] specified as the first argument.
4474 ** The name of the new collation sequence is specified as a UTF-8 string
4475 ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
4476 ** and a UTF-16 string for sqlite3_create_collation16(). In all cases
4477 ** the name is passed as the second function argument.
4479 ** The third argument may be one of the constants [SQLITE_UTF8],
4480 ** [SQLITE_UTF16LE] or [SQLITE_UTF16BE], indicating that the user-supplied
4481 ** routine expects to be passed pointers to strings encoded using UTF-8,
4482 ** UTF-16 little-endian, or UTF-16 big-endian, respectively. The
4483 ** third argument might also be [SQLITE_UTF16_ALIGNED] to indicate that
4484 ** the routine expects pointers to 16-bit word aligned strings
4485 ** of UTF-16 in the native byte order of the host computer.
4487 ** A pointer to the user supplied routine must be passed as the fifth
4488 ** argument. If it is NULL, this is the same as deleting the collation
4489 ** sequence (so that SQLite cannot call it anymore).
4490 ** Each time the application supplied function is invoked, it is passed
4491 ** as its first parameter a copy of the void* passed as the fourth argument
4492 ** to sqlite3_create_collation() or sqlite3_create_collation16().
4494 ** The remaining arguments to the application-supplied routine are two strings,
4495 ** each represented by a (length, data) pair and encoded in the encoding
4496 ** that was passed as the third argument when the collation sequence was
4497 ** registered. {END} The application defined collation routine should
4498 ** return negative, zero or positive if the first string is less than,
4499 ** equal to, or greater than the second string. i.e. (STRING1 - STRING2).
4501 ** The sqlite3_create_collation_v2() works like sqlite3_create_collation()
4502 ** except that it takes an extra argument which is a destructor for
4503 ** the collation. The destructor is called when the collation is
4504 ** destroyed and is passed a copy of the fourth parameter void* pointer
4505 ** of the sqlite3_create_collation_v2().
4506 ** Collations are destroyed when they are overridden by later calls to the
4507 ** collation creation functions or when the [database connection] is closed
4508 ** using [sqlite3_close()].
4512 ** {H16603} A successful call to the
4513 ** [sqlite3_create_collation_v2(B,X,E,P,F,D)] interface
4514 ** registers function F as the comparison function used to
4515 ** implement collation X on the [database connection] B for
4516 ** databases having encoding E.
4518 ** {H16604} SQLite understands the X parameter to
4519 ** [sqlite3_create_collation_v2(B,X,E,P,F,D)] as a zero-terminated
4520 ** UTF-8 string in which case is ignored for ASCII characters and
4521 ** is significant for non-ASCII characters.
4523 ** {H16606} Successive calls to [sqlite3_create_collation_v2(B,X,E,P,F,D)]
4524 ** with the same values for B, X, and E, override prior values
4527 ** {H16609} If the destructor D in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
4528 ** is not NULL then it is called with argument P when the
4529 ** collating function is dropped by SQLite.
4531 ** {H16612} A collating function is dropped when it is overloaded.
4533 ** {H16615} A collating function is dropped when the database connection
4534 ** is closed using [sqlite3_close()].
4536 ** {H16618} The pointer P in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
4537 ** is passed through as the first parameter to the comparison
4538 ** function F for all subsequent invocations of F.
4540 ** {H16621} A call to [sqlite3_create_collation(B,X,E,P,F)] is exactly
4541 ** the same as a call to [sqlite3_create_collation_v2()] with
4542 ** the same parameters and a NULL destructor.
4544 ** {H16624} Following a [sqlite3_create_collation_v2(B,X,E,P,F,D)],
4545 ** SQLite uses the comparison function F for all text comparison
4546 ** operations on the [database connection] B on text values that
4547 ** use the collating sequence named X.
4549 ** {H16627} The [sqlite3_create_collation16(B,X,E,P,F)] works the same
4550 ** as [sqlite3_create_collation(B,X,E,P,F)] except that the
4551 ** collation name X is understood as UTF-16 in native byte order
4552 ** instead of UTF-8.
4554 ** {H16630} When multiple comparison functions are available for the same
4555 ** collating sequence, SQLite chooses the one whose text encoding
4556 ** requires the least amount of conversion from the default
4557 ** text encoding of the database.
4559 int sqlite3_create_collation(
4564 int(*xCompare)(void*,int,const void*,int,const void*)
4566 int sqlite3_create_collation_v2(
4571 int(*xCompare)(void*,int,const void*,int,const void*),
4572 void(*xDestroy)(void*)
4574 int sqlite3_create_collation16(
4579 int(*xCompare)(void*,int,const void*,int,const void*)
4583 ** CAPI3REF: Collation Needed Callbacks {H16700} <S20300>
4585 ** To avoid having to register all collation sequences before a database
4586 ** can be used, a single callback function may be registered with the
4587 ** [database connection] to be called whenever an undefined collation
4588 ** sequence is required.
4590 ** If the function is registered using the sqlite3_collation_needed() API,
4591 ** then it is passed the names of undefined collation sequences as strings
4592 ** encoded in UTF-8. {H16703} If sqlite3_collation_needed16() is used,
4593 ** the names are passed as UTF-16 in machine native byte order.
4594 ** A call to either function replaces any existing callback.
4596 ** When the callback is invoked, the first argument passed is a copy
4597 ** of the second argument to sqlite3_collation_needed() or
4598 ** sqlite3_collation_needed16(). The second argument is the database
4599 ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
4600 ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
4601 ** sequence function required. The fourth parameter is the name of the
4602 ** required collation sequence.
4604 ** The callback function should register the desired collation using
4605 ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
4606 ** [sqlite3_create_collation_v2()].
4610 ** {H16702} A successful call to [sqlite3_collation_needed(D,P,F)]
4611 ** or [sqlite3_collation_needed16(D,P,F)] causes
4612 ** the [database connection] D to invoke callback F with first
4613 ** parameter P whenever it needs a comparison function for a
4614 ** collating sequence that it does not know about.
4616 ** {H16704} Each successful call to [sqlite3_collation_needed()] or
4617 ** [sqlite3_collation_needed16()] overrides the callback registered
4618 ** on the same [database connection] by prior calls to either
4621 ** {H16706} The name of the requested collating function passed in the
4622 ** 4th parameter to the callback is in UTF-8 if the callback
4623 ** was registered using [sqlite3_collation_needed()] and
4624 ** is in UTF-16 native byte order if the callback was
4625 ** registered using [sqlite3_collation_needed16()].
4627 int sqlite3_collation_needed(
4630 void(*)(void*,sqlite3*,int eTextRep,const char*)
4632 int sqlite3_collation_needed16(
4635 void(*)(void*,sqlite3*,int eTextRep,const void*)
4639 ** Specify the key for an encrypted database. This routine should be
4640 ** called right after sqlite3_open().
4642 ** The code to implement this API is not available in the public release
4646 sqlite3 *db, /* Database to be rekeyed */
4647 const void *pKey, int nKey /* The key */
4651 ** Change the key on an open database. If the current database is not
4652 ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
4653 ** database is decrypted.
4655 ** The code to implement this API is not available in the public release
4659 sqlite3 *db, /* Database to be rekeyed */
4660 const void *pKey, int nKey /* The new key */
4664 ** CAPI3REF: Suspend Execution For A Short Time {H10530} <S40410>
4666 ** The sqlite3_sleep() function causes the current thread to suspend execution
4667 ** for at least a number of milliseconds specified in its parameter.
4669 ** If the operating system does not support sleep requests with
4670 ** millisecond time resolution, then the time will be rounded up to
4671 ** the nearest second. The number of milliseconds of sleep actually
4672 ** requested from the operating system is returned.
4674 ** SQLite implements this interface by calling the xSleep()
4675 ** method of the default [sqlite3_vfs] object.
4679 ** {H10533} The [sqlite3_sleep(M)] interface invokes the xSleep
4680 ** method of the default [sqlite3_vfs|VFS] in order to
4681 ** suspend execution of the current thread for at least
4684 ** {H10536} The [sqlite3_sleep(M)] interface returns the number of
4685 ** milliseconds of sleep actually requested of the operating
4686 ** system, which might be larger than the parameter M.
4688 int sqlite3_sleep(int);
4691 ** CAPI3REF: Name Of The Folder Holding Temporary Files {H10310} <S20000>
4693 ** If this global variable is made to point to a string which is
4694 ** the name of a folder (a.k.a. directory), then all temporary files
4695 ** created by SQLite will be placed in that directory. If this variable
4696 ** is a NULL pointer, then SQLite performs a search for an appropriate
4697 ** temporary file directory.
4699 ** It is not safe to modify this variable once a [database connection]
4700 ** has been opened. It is intended that this variable be set once
4701 ** as part of process initialization and before any SQLite interface
4702 ** routines have been call and remain unchanged thereafter.
4704 SQLITE_EXTERN char *sqlite3_temp_directory;
4707 ** CAPI3REF: Test For Auto-Commit Mode {H12930} <S60200>
4708 ** KEYWORDS: {autocommit mode}
4710 ** The sqlite3_get_autocommit() interface returns non-zero or
4711 ** zero if the given database connection is or is not in autocommit mode,
4712 ** respectively. Autocommit mode is on by default.
4713 ** Autocommit mode is disabled by a [BEGIN] statement.
4714 ** Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
4716 ** If certain kinds of errors occur on a statement within a multi-statement
4717 ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
4718 ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
4719 ** transaction might be rolled back automatically. The only way to
4720 ** find out whether SQLite automatically rolled back the transaction after
4721 ** an error is to use this function.
4725 ** {H12931} The [sqlite3_get_autocommit(D)] interface returns non-zero or
4726 ** zero if the [database connection] D is or is not in autocommit
4727 ** mode, respectively.
4729 ** {H12932} Autocommit mode is on by default.
4731 ** {H12933} Autocommit mode is disabled by a successful [BEGIN] statement.
4733 ** {H12934} Autocommit mode is enabled by a successful [COMMIT] or [ROLLBACK]
4738 ** {A12936} If another thread changes the autocommit status of the database
4739 ** connection while this routine is running, then the return value
4742 int sqlite3_get_autocommit(sqlite3*);
4745 ** CAPI3REF: Find The Database Handle Of A Prepared Statement {H13120} <S60600>
4747 ** The sqlite3_db_handle interface returns the [database connection] handle
4748 ** to which a [prepared statement] belongs. The database handle returned by
4749 ** sqlite3_db_handle is the same database handle that was the first argument
4750 ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
4751 ** create the statement in the first place.
4755 ** {H13123} The [sqlite3_db_handle(S)] interface returns a pointer
4756 ** to the [database connection] associated with the
4757 ** [prepared statement] S.
4759 sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
4762 ** CAPI3REF: Find the next prepared statement {H13140} <S60600>
4764 ** This interface returns a pointer to the next [prepared statement] after
4765 ** pStmt associated with the [database connection] pDb. If pStmt is NULL
4766 ** then this interface returns a pointer to the first prepared statement
4767 ** associated with the database connection pDb. If no prepared statement
4768 ** satisfies the conditions of this routine, it returns NULL.
4772 ** {H13143} If D is a [database connection] that holds one or more
4773 ** unfinalized [prepared statements] and S is a NULL pointer,
4774 ** then [sqlite3_next_stmt(D, S)] routine shall return a pointer
4775 ** to one of the prepared statements associated with D.
4777 ** {H13146} If D is a [database connection] that holds no unfinalized
4778 ** [prepared statements] and S is a NULL pointer, then
4779 ** [sqlite3_next_stmt(D, S)] routine shall return a NULL pointer.
4781 ** {H13149} If S is a [prepared statement] in the [database connection] D
4782 ** and S is not the last prepared statement in D, then
4783 ** [sqlite3_next_stmt(D, S)] routine shall return a pointer
4784 ** to the next prepared statement in D after S.
4786 ** {H13152} If S is the last [prepared statement] in the
4787 ** [database connection] D then the [sqlite3_next_stmt(D, S)]
4788 ** routine shall return a NULL pointer.
4792 ** {A13154} The [database connection] pointer D in a call to
4793 ** [sqlite3_next_stmt(D,S)] must refer to an open database
4794 ** connection and in particular must not be a NULL pointer.
4796 sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
4799 ** CAPI3REF: Commit And Rollback Notification Callbacks {H12950} <S60400>
4801 ** The sqlite3_commit_hook() interface registers a callback
4802 ** function to be invoked whenever a transaction is committed.
4803 ** Any callback set by a previous call to sqlite3_commit_hook()
4804 ** for the same database connection is overridden.
4805 ** The sqlite3_rollback_hook() interface registers a callback
4806 ** function to be invoked whenever a transaction is committed.
4807 ** Any callback set by a previous call to sqlite3_commit_hook()
4808 ** for the same database connection is overridden.
4809 ** The pArg argument is passed through to the callback.
4810 ** If the callback on a commit hook function returns non-zero,
4811 ** then the commit is converted into a rollback.
4813 ** If another function was previously registered, its
4814 ** pArg value is returned. Otherwise NULL is returned.
4816 ** Registering a NULL function disables the callback.
4818 ** For the purposes of this API, a transaction is said to have been
4819 ** rolled back if an explicit "ROLLBACK" statement is executed, or
4820 ** an error or constraint causes an implicit rollback to occur.
4821 ** The rollback callback is not invoked if a transaction is
4822 ** automatically rolled back because the database connection is closed.
4823 ** The rollback callback is not invoked if a transaction is
4824 ** rolled back because a commit callback returned non-zero.
4825 ** <todo> Check on this </todo>
4829 ** {H12951} The [sqlite3_commit_hook(D,F,P)] interface registers the
4830 ** callback function F to be invoked with argument P whenever
4831 ** a transaction commits on the [database connection] D.
4833 ** {H12952} The [sqlite3_commit_hook(D,F,P)] interface returns the P argument
4834 ** from the previous call with the same [database connection] D,
4835 ** or NULL on the first call for a particular database connection D.
4837 ** {H12953} Each call to [sqlite3_commit_hook()] overwrites the callback
4838 ** registered by prior calls.
4840 ** {H12954} If the F argument to [sqlite3_commit_hook(D,F,P)] is NULL
4841 ** then the commit hook callback is canceled and no callback
4842 ** is invoked when a transaction commits.
4844 ** {H12955} If the commit callback returns non-zero then the commit is
4845 ** converted into a rollback.
4847 ** {H12961} The [sqlite3_rollback_hook(D,F,P)] interface registers the
4848 ** callback function F to be invoked with argument P whenever
4849 ** a transaction rolls back on the [database connection] D.
4851 ** {H12962} The [sqlite3_rollback_hook(D,F,P)] interface returns the P
4852 ** argument from the previous call with the same
4853 ** [database connection] D, or NULL on the first call
4854 ** for a particular database connection D.
4856 ** {H12963} Each call to [sqlite3_rollback_hook()] overwrites the callback
4857 ** registered by prior calls.
4859 ** {H12964} If the F argument to [sqlite3_rollback_hook(D,F,P)] is NULL
4860 ** then the rollback hook callback is canceled and no callback
4861 ** is invoked when a transaction rolls back.
4863 void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
4864 void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
4867 ** CAPI3REF: Data Change Notification Callbacks {H12970} <S60400>
4869 ** The sqlite3_update_hook() interface registers a callback function
4870 ** with the [database connection] identified by the first argument
4871 ** to be invoked whenever a row is updated, inserted or deleted.
4872 ** Any callback set by a previous call to this function
4873 ** for the same database connection is overridden.
4875 ** The second argument is a pointer to the function to invoke when a
4876 ** row is updated, inserted or deleted.
4877 ** The first argument to the callback is a copy of the third argument
4878 ** to sqlite3_update_hook().
4879 ** The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
4880 ** or [SQLITE_UPDATE], depending on the operation that caused the callback
4882 ** The third and fourth arguments to the callback contain pointers to the
4883 ** database and table name containing the affected row.
4884 ** The final callback parameter is the rowid of the row. In the case of
4885 ** an update, this is the rowid after the update takes place.
4887 ** The update hook is not invoked when internal system tables are
4888 ** modified (i.e. sqlite_master and sqlite_sequence).
4890 ** If another function was previously registered, its pArg value
4891 ** is returned. Otherwise NULL is returned.
4895 ** {H12971} The [sqlite3_update_hook(D,F,P)] interface causes the callback
4896 ** function F to be invoked with first parameter P whenever
4897 ** a table row is modified, inserted, or deleted on
4898 ** the [database connection] D.
4900 ** {H12973} The [sqlite3_update_hook(D,F,P)] interface returns the value
4901 ** of P for the previous call on the same [database connection] D,
4902 ** or NULL for the first call.
4904 ** {H12975} If the update hook callback F in [sqlite3_update_hook(D,F,P)]
4905 ** is NULL then the no update callbacks are made.
4907 ** {H12977} Each call to [sqlite3_update_hook(D,F,P)] overrides prior calls
4908 ** to the same interface on the same [database connection] D.
4910 ** {H12979} The update hook callback is not invoked when internal system
4911 ** tables such as sqlite_master and sqlite_sequence are modified.
4913 ** {H12981} The second parameter to the update callback
4914 ** is one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
4915 ** depending on the operation that caused the callback to be invoked.
4917 ** {H12983} The third and fourth arguments to the callback contain pointers
4918 ** to zero-terminated UTF-8 strings which are the names of the
4919 ** database and table that is being updated.
4921 ** {H12985} The final callback parameter is the rowid of the row after
4922 ** the change occurs.
4924 void *sqlite3_update_hook(
4926 void(*)(void *,int ,char const *,char const *,sqlite3_int64),
4931 ** CAPI3REF: Enable Or Disable Shared Pager Cache {H10330} <S30900>
4932 ** KEYWORDS: {shared cache} {shared cache mode}
4934 ** This routine enables or disables the sharing of the database cache
4935 ** and schema data structures between [database connection | connections]
4936 ** to the same database. Sharing is enabled if the argument is true
4937 ** and disabled if the argument is false.
4939 ** Cache sharing is enabled and disabled for an entire process. {END}
4940 ** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
4941 ** sharing was enabled or disabled for each thread separately.
4943 ** The cache sharing mode set by this interface effects all subsequent
4944 ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
4945 ** Existing database connections continue use the sharing mode
4946 ** that was in effect at the time they were opened.
4948 ** Virtual tables cannot be used with a shared cache. When shared
4949 ** cache is enabled, the [sqlite3_create_module()] API used to register
4950 ** virtual tables will always return an error.
4952 ** This routine returns [SQLITE_OK] if shared cache was enabled or disabled
4953 ** successfully. An [error code] is returned otherwise.
4955 ** Shared cache is disabled by default. But this might change in
4956 ** future releases of SQLite. Applications that care about shared
4957 ** cache setting should set it explicitly.
4961 ** {H10331} A successful invocation of [sqlite3_enable_shared_cache(B)]
4962 ** will enable or disable shared cache mode for any subsequently
4963 ** created [database connection] in the same process.
4965 ** {H10336} When shared cache is enabled, the [sqlite3_create_module()]
4966 ** interface will always return an error.
4968 ** {H10337} The [sqlite3_enable_shared_cache(B)] interface returns
4969 ** [SQLITE_OK] if shared cache was enabled or disabled successfully.
4971 ** {H10339} Shared cache is disabled by default.
4973 int sqlite3_enable_shared_cache(int);
4976 ** CAPI3REF: Attempt To Free Heap Memory {H17340} <S30220>
4978 ** The sqlite3_release_memory() interface attempts to free N bytes
4979 ** of heap memory by deallocating non-essential memory allocations
4980 ** held by the database library. {END} Memory used to cache database
4981 ** pages to improve performance is an example of non-essential memory.
4982 ** sqlite3_release_memory() returns the number of bytes actually freed,
4983 ** which might be more or less than the amount requested.
4987 ** {H17341} The [sqlite3_release_memory(N)] interface attempts to
4988 ** free N bytes of heap memory by deallocating non-essential
4989 ** memory allocations held by the database library.
4991 ** {H16342} The [sqlite3_release_memory(N)] returns the number
4992 ** of bytes actually freed, which might be more or less
4993 ** than the amount requested.
4995 int sqlite3_release_memory(int);
4998 ** CAPI3REF: Impose A Limit On Heap Size {H17350} <S30220>
5000 ** The sqlite3_soft_heap_limit() interface places a "soft" limit
5001 ** on the amount of heap memory that may be allocated by SQLite.
5002 ** If an internal allocation is requested that would exceed the
5003 ** soft heap limit, [sqlite3_release_memory()] is invoked one or
5004 ** more times to free up some space before the allocation is performed.
5006 ** The limit is called "soft", because if [sqlite3_release_memory()]
5007 ** cannot free sufficient memory to prevent the limit from being exceeded,
5008 ** the memory is allocated anyway and the current operation proceeds.
5010 ** A negative or zero value for N means that there is no soft heap limit and
5011 ** [sqlite3_release_memory()] will only be called when memory is exhausted.
5012 ** The default value for the soft heap limit is zero.
5014 ** SQLite makes a best effort to honor the soft heap limit.
5015 ** But if the soft heap limit cannot be honored, execution will
5016 ** continue without error or notification. This is why the limit is
5017 ** called a "soft" limit. It is advisory only.
5019 ** Prior to SQLite version 3.5.0, this routine only constrained the memory
5020 ** allocated by a single thread - the same thread in which this routine
5021 ** runs. Beginning with SQLite version 3.5.0, the soft heap limit is
5022 ** applied to all threads. The value specified for the soft heap limit
5023 ** is an upper bound on the total memory allocation for all threads. In
5024 ** version 3.5.0 there is no mechanism for limiting the heap usage for
5025 ** individual threads.
5029 ** {H16351} The [sqlite3_soft_heap_limit(N)] interface places a soft limit
5030 ** of N bytes on the amount of heap memory that may be allocated
5031 ** using [sqlite3_malloc()] or [sqlite3_realloc()] at any point
5034 ** {H16352} If a call to [sqlite3_malloc()] or [sqlite3_realloc()] would
5035 ** cause the total amount of allocated memory to exceed the
5036 ** soft heap limit, then [sqlite3_release_memory()] is invoked
5037 ** in an attempt to reduce the memory usage prior to proceeding
5038 ** with the memory allocation attempt.
5040 ** {H16353} Calls to [sqlite3_malloc()] or [sqlite3_realloc()] that trigger
5041 ** attempts to reduce memory usage through the soft heap limit
5042 ** mechanism continue even if the attempt to reduce memory
5043 ** usage is unsuccessful.
5045 ** {H16354} A negative or zero value for N in a call to
5046 ** [sqlite3_soft_heap_limit(N)] means that there is no soft
5047 ** heap limit and [sqlite3_release_memory()] will only be
5048 ** called when memory is completely exhausted.
5050 ** {H16355} The default value for the soft heap limit is zero.
5052 ** {H16358} Each call to [sqlite3_soft_heap_limit(N)] overrides the
5053 ** values set by all prior calls.
5055 void sqlite3_soft_heap_limit(int);
5058 ** CAPI3REF: Extract Metadata About A Column Of A Table {H12850} <S60300>
5060 ** This routine returns metadata about a specific column of a specific
5061 ** database table accessible using the [database connection] handle
5062 ** passed as the first function argument.
5064 ** The column is identified by the second, third and fourth parameters to
5065 ** this function. The second parameter is either the name of the database
5066 ** (i.e. "main", "temp" or an attached database) containing the specified
5067 ** table or NULL. If it is NULL, then all attached databases are searched
5068 ** for the table using the same algorithm used by the database engine to
5069 ** resolve unqualified table references.
5071 ** The third and fourth parameters to this function are the table and column
5072 ** name of the desired column, respectively. Neither of these parameters
5075 ** Metadata is returned by writing to the memory locations passed as the 5th
5076 ** and subsequent parameters to this function. Any of these arguments may be
5077 ** NULL, in which case the corresponding element of metadata is omitted.
5080 ** <table border="1">
5081 ** <tr><th> Parameter <th> Output<br>Type <th> Description
5083 ** <tr><td> 5th <td> const char* <td> Data type
5084 ** <tr><td> 6th <td> const char* <td> Name of default collation sequence
5085 ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
5086 ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
5087 ** <tr><td> 9th <td> int <td> True if column is AUTOINCREMENT
5091 ** The memory pointed to by the character pointers returned for the
5092 ** declaration type and collation sequence is valid only until the next
5093 ** call to any SQLite API function.
5095 ** If the specified table is actually a view, an [error code] is returned.
5097 ** If the specified column is "rowid", "oid" or "_rowid_" and an
5098 ** INTEGER PRIMARY KEY column has been explicitly declared, then the output
5099 ** parameters are set for the explicitly declared column. If there is no
5100 ** explicitly declared INTEGER PRIMARY KEY column, then the output
5101 ** parameters are set as follows:
5104 ** data type: "INTEGER"
5105 ** collation sequence: "BINARY"
5108 ** auto increment: 0
5111 ** This function may load one or more schemas from database files. If an
5112 ** error occurs during this process, or if the requested table or column
5113 ** cannot be found, an [error code] is returned and an error message left
5114 ** in the [database connection] (to be retrieved using sqlite3_errmsg()).
5116 ** This API is only available if the library was compiled with the
5117 ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
5119 int sqlite3_table_column_metadata(
5120 sqlite3 *db, /* Connection handle */
5121 const char *zDbName, /* Database name or NULL */
5122 const char *zTableName, /* Table name */
5123 const char *zColumnName, /* Column name */
5124 char const **pzDataType, /* OUTPUT: Declared data type */
5125 char const **pzCollSeq, /* OUTPUT: Collation sequence name */
5126 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
5127 int *pPrimaryKey, /* OUTPUT: True if column part of PK */
5128 int *pAutoinc /* OUTPUT: True if column is auto-increment */
5132 ** CAPI3REF: Load An Extension {H12600} <S20500>
5134 ** This interface loads an SQLite extension library from the named file.
5136 ** {H12601} The sqlite3_load_extension() interface attempts to load an
5137 ** SQLite extension library contained in the file zFile.
5139 ** {H12602} The entry point is zProc.
5141 ** {H12603} zProc may be 0, in which case the name of the entry point
5142 ** defaults to "sqlite3_extension_init".
5144 ** {H12604} The sqlite3_load_extension() interface shall return
5145 ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
5147 ** {H12605} If an error occurs and pzErrMsg is not 0, then the
5148 ** [sqlite3_load_extension()] interface shall attempt to
5149 ** fill *pzErrMsg with error message text stored in memory
5150 ** obtained from [sqlite3_malloc()]. {END} The calling function
5151 ** should free this memory by calling [sqlite3_free()].
5153 ** {H12606} Extension loading must be enabled using
5154 ** [sqlite3_enable_load_extension()] prior to calling this API,
5155 ** otherwise an error will be returned.
5157 int sqlite3_load_extension(
5158 sqlite3 *db, /* Load the extension into this database connection */
5159 const char *zFile, /* Name of the shared library containing extension */
5160 const char *zProc, /* Entry point. Derived from zFile if 0 */
5161 char **pzErrMsg /* Put error message here if not 0 */
5165 ** CAPI3REF: Enable Or Disable Extension Loading {H12620} <S20500>
5167 ** So as not to open security holes in older applications that are
5168 ** unprepared to deal with extension loading, and as a means of disabling
5169 ** extension loading while evaluating user-entered SQL, the following API
5170 ** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
5172 ** Extension loading is off by default. See ticket #1863.
5174 ** {H12621} Call the sqlite3_enable_load_extension() routine with onoff==1
5175 ** to turn extension loading on and call it with onoff==0 to turn
5176 ** it back off again.
5178 ** {H12622} Extension loading is off by default.
5180 int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
5183 ** CAPI3REF: Automatically Load An Extensions {H12640} <S20500>
5185 ** This API can be invoked at program startup in order to register
5186 ** one or more statically linked extensions that will be available
5187 ** to all new [database connections]. {END}
5189 ** This routine stores a pointer to the extension in an array that is
5190 ** obtained from [sqlite3_malloc()]. If you run a memory leak checker
5191 ** on your program and it reports a leak because of this array, invoke
5192 ** [sqlite3_reset_auto_extension()] prior to shutdown to free the memory.
5194 ** {H12641} This function registers an extension entry point that is
5195 ** automatically invoked whenever a new [database connection]
5196 ** is opened using [sqlite3_open()], [sqlite3_open16()],
5197 ** or [sqlite3_open_v2()].
5199 ** {H12642} Duplicate extensions are detected so calling this routine
5200 ** multiple times with the same extension is harmless.
5202 ** {H12643} This routine stores a pointer to the extension in an array
5203 ** that is obtained from [sqlite3_malloc()].
5205 ** {H12644} Automatic extensions apply across all threads.
5207 int sqlite3_auto_extension(void *xEntryPoint);
5210 ** CAPI3REF: Reset Automatic Extension Loading {H12660} <S20500>
5212 ** This function disables all previously registered automatic
5213 ** extensions. {END} It undoes the effect of all prior
5214 ** [sqlite3_auto_extension()] calls.
5216 ** {H12661} This function disables all previously registered
5217 ** automatic extensions.
5219 ** {H12662} This function disables automatic extensions in all threads.
5221 void sqlite3_reset_auto_extension(void);
5224 ****** EXPERIMENTAL - subject to change without notice **************
5226 ** The interface to the virtual-table mechanism is currently considered
5227 ** to be experimental. The interface might change in incompatible ways.
5228 ** If this is a problem for you, do not use the interface at this time.
5230 ** When the virtual-table mechanism stabilizes, we will declare the
5231 ** interface fixed, support it indefinitely, and remove this comment.
5235 ** Structures used by the virtual table interface
5237 typedef struct sqlite3_vtab sqlite3_vtab;
5238 typedef struct sqlite3_index_info sqlite3_index_info;
5239 typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
5240 typedef struct sqlite3_module sqlite3_module;
5243 ** CAPI3REF: Virtual Table Object {H18000} <S20400>
5244 ** KEYWORDS: sqlite3_module
5247 ** A module is a class of virtual tables. Each module is defined
5248 ** by an instance of the following structure. This structure consists
5249 ** mostly of methods for the module.
5251 ** This interface is experimental and is subject to change or
5252 ** removal in future releases of SQLite.
5254 struct sqlite3_module {
5256 int (*xCreate)(sqlite3*, void *pAux,
5257 int argc, const char *const*argv,
5258 sqlite3_vtab **ppVTab, char**);
5259 int (*xConnect)(sqlite3*, void *pAux,
5260 int argc, const char *const*argv,
5261 sqlite3_vtab **ppVTab, char**);
5262 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
5263 int (*xDisconnect)(sqlite3_vtab *pVTab);
5264 int (*xDestroy)(sqlite3_vtab *pVTab);
5265 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
5266 int (*xClose)(sqlite3_vtab_cursor*);
5267 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
5268 int argc, sqlite3_value **argv);
5269 int (*xNext)(sqlite3_vtab_cursor*);
5270 int (*xEof)(sqlite3_vtab_cursor*);
5271 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
5272 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
5273 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
5274 int (*xBegin)(sqlite3_vtab *pVTab);
5275 int (*xSync)(sqlite3_vtab *pVTab);
5276 int (*xCommit)(sqlite3_vtab *pVTab);
5277 int (*xRollback)(sqlite3_vtab *pVTab);
5278 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
5279 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
5281 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
5285 ** CAPI3REF: Virtual Table Indexing Information {H18100} <S20400>
5286 ** KEYWORDS: sqlite3_index_info
5289 ** The sqlite3_index_info structure and its substructures is used to
5290 ** pass information into and receive the reply from the xBestIndex
5291 ** method of an sqlite3_module. The fields under **Inputs** are the
5292 ** inputs to xBestIndex and are read-only. xBestIndex inserts its
5293 ** results into the **Outputs** fields.
5295 ** The aConstraint[] array records WHERE clause constraints of the form:
5297 ** <pre>column OP expr</pre>
5299 ** where OP is =, <, <=, >, or >=. The particular operator is
5300 ** stored in aConstraint[].op. The index of the column is stored in
5301 ** aConstraint[].iColumn. aConstraint[].usable is TRUE if the
5302 ** expr on the right-hand side can be evaluated (and thus the constraint
5303 ** is usable) and false if it cannot.
5305 ** The optimizer automatically inverts terms of the form "expr OP column"
5306 ** and makes other simplifications to the WHERE clause in an attempt to
5307 ** get as many WHERE clause terms into the form shown above as possible.
5308 ** The aConstraint[] array only reports WHERE clause terms in the correct
5309 ** form that refer to the particular virtual table being queried.
5311 ** Information about the ORDER BY clause is stored in aOrderBy[].
5312 ** Each term of aOrderBy records a column of the ORDER BY clause.
5314 ** The xBestIndex method must fill aConstraintUsage[] with information
5315 ** about what parameters to pass to xFilter. If argvIndex>0 then
5316 ** the right-hand side of the corresponding aConstraint[] is evaluated
5317 ** and becomes the argvIndex-th entry in argv. If aConstraintUsage[].omit
5318 ** is true, then the constraint is assumed to be fully handled by the
5319 ** virtual table and is not checked again by SQLite.
5321 ** The idxNum and idxPtr values are recorded and passed into xFilter.
5322 ** sqlite3_free() is used to free idxPtr if needToFreeIdxPtr is true.
5324 ** The orderByConsumed means that output from xFilter will occur in
5325 ** the correct order to satisfy the ORDER BY clause so that no separate
5326 ** sorting step is required.
5328 ** The estimatedCost value is an estimate of the cost of doing the
5329 ** particular lookup. A full scan of a table with N entries should have
5330 ** a cost of N. A binary search of a table of N entries should have a
5331 ** cost of approximately log(N).
5333 ** This interface is experimental and is subject to change or
5334 ** removal in future releases of SQLite.
5336 struct sqlite3_index_info {
5338 int nConstraint; /* Number of entries in aConstraint */
5339 struct sqlite3_index_constraint {
5340 int iColumn; /* Column on left-hand side of constraint */
5341 unsigned char op; /* Constraint operator */
5342 unsigned char usable; /* True if this constraint is usable */
5343 int iTermOffset; /* Used internally - xBestIndex should ignore */
5344 } *aConstraint; /* Table of WHERE clause constraints */
5345 int nOrderBy; /* Number of terms in the ORDER BY clause */
5346 struct sqlite3_index_orderby {
5347 int iColumn; /* Column number */
5348 unsigned char desc; /* True for DESC. False for ASC. */
5349 } *aOrderBy; /* The ORDER BY clause */
5351 struct sqlite3_index_constraint_usage {
5352 int argvIndex; /* if >0, constraint is part of argv to xFilter */
5353 unsigned char omit; /* Do not code a test for this constraint */
5354 } *aConstraintUsage;
5355 int idxNum; /* Number used to identify the index */
5356 char *idxStr; /* String, possibly obtained from sqlite3_malloc */
5357 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
5358 int orderByConsumed; /* True if output is already ordered */
5359 double estimatedCost; /* Estimated cost of using this index */
5361 #define SQLITE_INDEX_CONSTRAINT_EQ 2
5362 #define SQLITE_INDEX_CONSTRAINT_GT 4
5363 #define SQLITE_INDEX_CONSTRAINT_LE 8
5364 #define SQLITE_INDEX_CONSTRAINT_LT 16
5365 #define SQLITE_INDEX_CONSTRAINT_GE 32
5366 #define SQLITE_INDEX_CONSTRAINT_MATCH 64
5369 ** CAPI3REF: Register A Virtual Table Implementation {H18200} <S20400>
5372 ** This routine is used to register a new module name with a
5373 ** [database connection]. Module names must be registered before
5374 ** creating new virtual tables on the module, or before using
5375 ** preexisting virtual tables of the module.
5377 ** This interface is experimental and is subject to change or
5378 ** removal in future releases of SQLite.
5380 int sqlite3_create_module(
5381 sqlite3 *db, /* SQLite connection to register module with */
5382 const char *zName, /* Name of the module */
5383 const sqlite3_module *, /* Methods for the module */
5384 void * /* Client data for xCreate/xConnect */
5388 ** CAPI3REF: Register A Virtual Table Implementation {H18210} <S20400>
5391 ** This routine is identical to the [sqlite3_create_module()] method above,
5392 ** except that it allows a destructor function to be specified. It is
5393 ** even more experimental than the rest of the virtual tables API.
5395 int sqlite3_create_module_v2(
5396 sqlite3 *db, /* SQLite connection to register module with */
5397 const char *zName, /* Name of the module */
5398 const sqlite3_module *, /* Methods for the module */
5399 void *, /* Client data for xCreate/xConnect */
5400 void(*xDestroy)(void*) /* Module destructor function */
5404 ** CAPI3REF: Virtual Table Instance Object {H18010} <S20400>
5405 ** KEYWORDS: sqlite3_vtab
5408 ** Every module implementation uses a subclass of the following structure
5409 ** to describe a particular instance of the module. Each subclass will
5410 ** be tailored to the specific needs of the module implementation.
5411 ** The purpose of this superclass is to define certain fields that are
5412 ** common to all module implementations.
5414 ** Virtual tables methods can set an error message by assigning a
5415 ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
5416 ** take care that any prior string is freed by a call to [sqlite3_free()]
5417 ** prior to assigning a new string to zErrMsg. After the error message
5418 ** is delivered up to the client application, the string will be automatically
5419 ** freed by sqlite3_free() and the zErrMsg field will be zeroed. Note
5420 ** that sqlite3_mprintf() and sqlite3_free() are used on the zErrMsg field
5421 ** since virtual tables are commonly implemented in loadable extensions which
5422 ** do not have access to sqlite3MPrintf() or sqlite3Free().
5424 ** This interface is experimental and is subject to change or
5425 ** removal in future releases of SQLite.
5427 struct sqlite3_vtab {
5428 const sqlite3_module *pModule; /* The module for this virtual table */
5429 int nRef; /* Used internally */
5430 char *zErrMsg; /* Error message from sqlite3_mprintf() */
5431 /* Virtual table implementations will typically add additional fields */
5435 ** CAPI3REF: Virtual Table Cursor Object {H18020} <S20400>
5436 ** KEYWORDS: sqlite3_vtab_cursor
5439 ** Every module implementation uses a subclass of the following structure
5440 ** to describe cursors that point into the virtual table and are used
5441 ** to loop through the virtual table. Cursors are created using the
5442 ** xOpen method of the module. Each module implementation will define
5443 ** the content of a cursor structure to suit its own needs.
5445 ** This superclass exists in order to define fields of the cursor that
5446 ** are common to all implementations.
5448 ** This interface is experimental and is subject to change or
5449 ** removal in future releases of SQLite.
5451 struct sqlite3_vtab_cursor {
5452 sqlite3_vtab *pVtab; /* Virtual table of this cursor */
5453 /* Virtual table implementations will typically add additional fields */
5457 ** CAPI3REF: Declare The Schema Of A Virtual Table {H18280} <S20400>
5460 ** The xCreate and xConnect methods of a module use the following API
5461 ** to declare the format (the names and datatypes of the columns) of
5462 ** the virtual tables they implement.
5464 ** This interface is experimental and is subject to change or
5465 ** removal in future releases of SQLite.
5467 int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);
5470 ** CAPI3REF: Overload A Function For A Virtual Table {H18300} <S20400>
5473 ** Virtual tables can provide alternative implementations of functions
5474 ** using the xFindFunction method. But global versions of those functions
5475 ** must exist in order to be overloaded.
5477 ** This API makes sure a global version of a function with a particular
5478 ** name and number of parameters exists. If no such function exists
5479 ** before this API is called, a new function is created. The implementation
5480 ** of the new function always causes an exception to be thrown. So
5481 ** the new function is not good for anything by itself. Its only
5482 ** purpose is to be a placeholder function that can be overloaded
5483 ** by virtual tables.
5485 ** This API should be considered part of the virtual table interface,
5486 ** which is experimental and subject to change.
5488 int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
5491 ** The interface to the virtual-table mechanism defined above (back up
5492 ** to a comment remarkably similar to this one) is currently considered
5493 ** to be experimental. The interface might change in incompatible ways.
5494 ** If this is a problem for you, do not use the interface at this time.
5496 ** When the virtual-table mechanism stabilizes, we will declare the
5497 ** interface fixed, support it indefinitely, and remove this comment.
5499 ****** EXPERIMENTAL - subject to change without notice **************
5503 ** CAPI3REF: A Handle To An Open BLOB {H17800} <S30230>
5504 ** KEYWORDS: {BLOB handle} {BLOB handles}
5506 ** An instance of this object represents an open BLOB on which
5507 ** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
5508 ** Objects of this type are created by [sqlite3_blob_open()]
5509 ** and destroyed by [sqlite3_blob_close()].
5510 ** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
5511 ** can be used to read or write small subsections of the BLOB.
5512 ** The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
5514 typedef struct sqlite3_blob sqlite3_blob;
5517 ** CAPI3REF: Open A BLOB For Incremental I/O {H17810} <S30230>
5519 ** This interfaces opens a [BLOB handle | handle] to the BLOB located
5520 ** in row iRow, column zColumn, table zTable in database zDb;
5521 ** in other words, the same BLOB that would be selected by:
5524 ** SELECT zColumn FROM zDb.zTable WHERE rowid = iRow;
5527 ** If the flags parameter is non-zero, the the BLOB is opened for read
5528 ** and write access. If it is zero, the BLOB is opened for read access.
5530 ** Note that the database name is not the filename that contains
5531 ** the database but rather the symbolic name of the database that
5532 ** is assigned when the database is connected using [ATTACH].
5533 ** For the main database file, the database name is "main".
5534 ** For TEMP tables, the database name is "temp".
5536 ** On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
5537 ** to *ppBlob. Otherwise an [error code] is returned and any value written
5538 ** to *ppBlob should not be used by the caller.
5539 ** This function sets the [database connection] error code and message
5540 ** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()].
5542 ** If the row that a BLOB handle points to is modified by an
5543 ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
5544 ** then the BLOB handle is marked as "expired".
5545 ** This is true if any column of the row is changed, even a column
5546 ** other than the one the BLOB handle is open on.
5547 ** Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
5548 ** a expired BLOB handle fail with an return code of [SQLITE_ABORT].
5549 ** Changes written into a BLOB prior to the BLOB expiring are not
5550 ** rollback by the expiration of the BLOB. Such changes will eventually
5551 ** commit if the transaction continues to completion.
5555 ** {H17813} A successful invocation of the [sqlite3_blob_open(D,B,T,C,R,F,P)]
5556 ** interface shall open an [sqlite3_blob] object P on the BLOB
5557 ** in column C of the table T in the database B on
5558 ** the [database connection] D.
5560 ** {H17814} A successful invocation of [sqlite3_blob_open(D,...)] shall start
5561 ** a new transaction on the [database connection] D if that
5562 ** connection is not already in a transaction.
5564 ** {H17816} The [sqlite3_blob_open(D,B,T,C,R,F,P)] interface shall open
5565 ** the BLOB for read and write access if and only if the F
5566 ** parameter is non-zero.
5568 ** {H17819} The [sqlite3_blob_open()] interface shall return [SQLITE_OK] on
5569 ** success and an appropriate [error code] on failure.
5571 ** {H17821} If an error occurs during evaluation of [sqlite3_blob_open(D,...)]
5572 ** then subsequent calls to [sqlite3_errcode(D)],
5573 ** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
5574 ** information appropriate for that error.
5576 ** {H17824} If any column in the row that a [sqlite3_blob] has open is
5577 ** changed by a separate [UPDATE] or [DELETE] statement or by
5578 ** an [ON CONFLICT] side effect, then the [sqlite3_blob] shall
5579 ** be marked as invalid.
5581 int sqlite3_blob_open(
5585 const char *zColumn,
5588 sqlite3_blob **ppBlob
5592 ** CAPI3REF: Close A BLOB Handle {H17830} <S30230>
5594 ** Closes an open [BLOB handle].
5596 ** Closing a BLOB shall cause the current transaction to commit
5597 ** if there are no other BLOBs, no pending prepared statements, and the
5598 ** database connection is in [autocommit mode].
5599 ** If any writes were made to the BLOB, they might be held in cache
5600 ** until the close operation if they will fit. {END}
5602 ** Closing the BLOB often forces the changes
5603 ** out to disk and so if any I/O errors occur, they will likely occur
5604 ** at the time when the BLOB is closed. {H17833} Any errors that occur during
5605 ** closing are reported as a non-zero return value.
5607 ** The BLOB is closed unconditionally. Even if this routine returns
5608 ** an error code, the BLOB is still closed.
5612 ** {H17833} The [sqlite3_blob_close(P)] interface closes an [sqlite3_blob]
5613 ** object P previously opened using [sqlite3_blob_open()].
5615 ** {H17836} Closing an [sqlite3_blob] object using
5616 ** [sqlite3_blob_close()] shall cause the current transaction to
5617 ** commit if there are no other open [sqlite3_blob] objects
5618 ** or [prepared statements] on the same [database connection] and
5619 ** the database connection is in [autocommit mode].
5621 ** {H17839} The [sqlite3_blob_close(P)] interfaces shall close the
5622 ** [sqlite3_blob] object P unconditionally, even if
5623 ** [sqlite3_blob_close(P)] returns something other than [SQLITE_OK].
5625 int sqlite3_blob_close(sqlite3_blob *);
5628 ** CAPI3REF: Return The Size Of An Open BLOB {H17840} <S30230>
5630 ** Returns the size in bytes of the BLOB accessible via the open
5631 ** []BLOB handle] in its only argument.
5635 ** {H17843} The [sqlite3_blob_bytes(P)] interface returns the size
5636 ** in bytes of the BLOB that the [sqlite3_blob] object P
5639 int sqlite3_blob_bytes(sqlite3_blob *);
5642 ** CAPI3REF: Read Data From A BLOB Incrementally {H17850} <S30230>
5644 ** This function is used to read data from an open [BLOB handle] into a
5645 ** caller-supplied buffer. N bytes of data are copied into buffer Z
5646 ** from the open BLOB, starting at offset iOffset.
5648 ** If offset iOffset is less than N bytes from the end of the BLOB,
5649 ** [SQLITE_ERROR] is returned and no data is read. If N or iOffset is
5650 ** less than zero, [SQLITE_ERROR] is returned and no data is read.
5652 ** An attempt to read from an expired [BLOB handle] fails with an
5653 ** error code of [SQLITE_ABORT].
5655 ** On success, SQLITE_OK is returned.
5656 ** Otherwise, an [error code] or an [extended error code] is returned.
5660 ** {H17853} A successful invocation of [sqlite3_blob_read(P,Z,N,X)]
5661 ** shall reads N bytes of data out of the BLOB referenced by
5662 ** [BLOB handle] P beginning at offset X and store those bytes
5665 ** {H17856} In [sqlite3_blob_read(P,Z,N,X)] if the size of the BLOB
5666 ** is less than N+X bytes, then the function shall leave the
5667 ** Z buffer unchanged and return [SQLITE_ERROR].
5669 ** {H17859} In [sqlite3_blob_read(P,Z,N,X)] if X or N is less than zero
5670 ** then the function shall leave the Z buffer unchanged
5671 ** and return [SQLITE_ERROR].
5673 ** {H17862} The [sqlite3_blob_read(P,Z,N,X)] interface shall return [SQLITE_OK]
5674 ** if N bytes are successfully read into buffer Z.
5676 ** {H17863} If the [BLOB handle] P is expired and X and N are within bounds
5677 ** then [sqlite3_blob_read(P,Z,N,X)] shall leave the Z buffer
5678 ** unchanged and return [SQLITE_ABORT].
5680 ** {H17865} If the requested read could not be completed,
5681 ** the [sqlite3_blob_read(P,Z,N,X)] interface shall return an
5682 ** appropriate [error code] or [extended error code].
5684 ** {H17868} If an error occurs during evaluation of [sqlite3_blob_read(P,...)]
5685 ** then subsequent calls to [sqlite3_errcode(D)],
5686 ** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
5687 ** information appropriate for that error, where D is the
5688 ** [database connection] that was used to open the [BLOB handle] P.
5690 int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
5693 ** CAPI3REF: Write Data Into A BLOB Incrementally {H17870} <S30230>
5695 ** This function is used to write data into an open [BLOB handle] from a
5696 ** caller-supplied buffer. N bytes of data are copied from the buffer Z
5697 ** into the open BLOB, starting at offset iOffset.
5699 ** If the [BLOB handle] passed as the first argument was not opened for
5700 ** writing (the flags parameter to [sqlite3_blob_open()] was zero),
5701 ** this function returns [SQLITE_READONLY].
5703 ** This function may only modify the contents of the BLOB; it is
5704 ** not possible to increase the size of a BLOB using this API.
5705 ** If offset iOffset is less than N bytes from the end of the BLOB,
5706 ** [SQLITE_ERROR] is returned and no data is written. If N is
5707 ** less than zero [SQLITE_ERROR] is returned and no data is written.
5709 ** An attempt to write to an expired [BLOB handle] fails with an
5710 ** error code of [SQLITE_ABORT]. Writes to the BLOB that occurred
5711 ** before the [BLOB handle] expired are not rolled back by the
5712 ** expiration of the handle, though of course those changes might
5713 ** have been overwritten by the statement that expired the BLOB handle
5714 ** or by other independent statements.
5716 ** On success, SQLITE_OK is returned.
5717 ** Otherwise, an [error code] or an [extended error code] is returned.
5721 ** {H17873} A successful invocation of [sqlite3_blob_write(P,Z,N,X)]
5722 ** shall write N bytes of data from buffer Z into the BLOB
5723 ** referenced by [BLOB handle] P beginning at offset X into
5726 ** {H17874} In the absence of other overridding changes, the changes
5727 ** written to a BLOB by [sqlite3_blob_write()] shall
5728 ** remain in effect after the associated [BLOB handle] expires.
5730 ** {H17875} If the [BLOB handle] P was opened for reading only then
5731 ** an invocation of [sqlite3_blob_write(P,Z,N,X)] shall leave
5732 ** the referenced BLOB unchanged and return [SQLITE_READONLY].
5734 ** {H17876} If the size of the BLOB referenced by [BLOB handle] P is
5735 ** less than N+X bytes then [sqlite3_blob_write(P,Z,N,X)] shall
5736 ** leave the BLOB unchanged and return [SQLITE_ERROR].
5738 ** {H17877} If the [BLOB handle] P is expired and X and N are within bounds
5739 ** then [sqlite3_blob_read(P,Z,N,X)] shall leave the BLOB
5740 ** unchanged and return [SQLITE_ABORT].
5742 ** {H17879} If X or N are less than zero then [sqlite3_blob_write(P,Z,N,X)]
5743 ** shall leave the BLOB referenced by [BLOB handle] P unchanged
5744 ** and return [SQLITE_ERROR].
5746 ** {H17882} The [sqlite3_blob_write(P,Z,N,X)] interface shall return
5747 ** [SQLITE_OK] if N bytes where successfully written into the BLOB.
5749 ** {H17885} If the requested write could not be completed,
5750 ** the [sqlite3_blob_write(P,Z,N,X)] interface shall return an
5751 ** appropriate [error code] or [extended error code].
5753 ** {H17888} If an error occurs during evaluation of [sqlite3_blob_write(D,...)]
5754 ** then subsequent calls to [sqlite3_errcode(D)],
5755 ** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
5756 ** information appropriate for that error.
5758 int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
5761 ** CAPI3REF: Virtual File System Objects {H11200} <S20100>
5763 ** A virtual filesystem (VFS) is an [sqlite3_vfs] object
5764 ** that SQLite uses to interact
5765 ** with the underlying operating system. Most SQLite builds come with a
5766 ** single default VFS that is appropriate for the host computer.
5767 ** New VFSes can be registered and existing VFSes can be unregistered.
5768 ** The following interfaces are provided.
5770 ** The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
5771 ** Names are case sensitive.
5772 ** Names are zero-terminated UTF-8 strings.
5773 ** If there is no match, a NULL pointer is returned.
5774 ** If zVfsName is NULL then the default VFS is returned.
5776 ** New VFSes are registered with sqlite3_vfs_register().
5777 ** Each new VFS becomes the default VFS if the makeDflt flag is set.
5778 ** The same VFS can be registered multiple times without injury.
5779 ** To make an existing VFS into the default VFS, register it again
5780 ** with the makeDflt flag set. If two different VFSes with the
5781 ** same name are registered, the behavior is undefined. If a
5782 ** VFS is registered with a name that is NULL or an empty string,
5783 ** then the behavior is undefined.
5785 ** Unregister a VFS with the sqlite3_vfs_unregister() interface.
5786 ** If the default VFS is unregistered, another VFS is chosen as
5787 ** the default. The choice for the new VFS is arbitrary.
5791 ** {H11203} The [sqlite3_vfs_find(N)] interface returns a pointer to the
5792 ** registered [sqlite3_vfs] object whose name exactly matches
5793 ** the zero-terminated UTF-8 string N, or it returns NULL if
5794 ** there is no match.
5796 ** {H11206} If the N parameter to [sqlite3_vfs_find(N)] is NULL then
5797 ** the function returns a pointer to the default [sqlite3_vfs]
5798 ** object if there is one, or NULL if there is no default
5799 ** [sqlite3_vfs] object.
5801 ** {H11209} The [sqlite3_vfs_register(P,F)] interface registers the
5802 ** well-formed [sqlite3_vfs] object P using the name given
5803 ** by the zName field of the object.
5805 ** {H11212} Using the [sqlite3_vfs_register(P,F)] interface to register
5806 ** the same [sqlite3_vfs] object multiple times is a harmless no-op.
5808 ** {H11215} The [sqlite3_vfs_register(P,F)] interface makes the [sqlite3_vfs]
5809 ** object P the default [sqlite3_vfs] object if F is non-zero.
5811 ** {H11218} The [sqlite3_vfs_unregister(P)] interface unregisters the
5812 ** [sqlite3_vfs] object P so that it is no longer returned by
5813 ** subsequent calls to [sqlite3_vfs_find()].
5815 sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
5816 int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
5817 int sqlite3_vfs_unregister(sqlite3_vfs*);
5820 ** CAPI3REF: Mutexes {H17000} <S20000>
5822 ** The SQLite core uses these routines for thread
5823 ** synchronization. Though they are intended for internal
5824 ** use by SQLite, code that links against SQLite is
5825 ** permitted to use any of these routines.
5827 ** The SQLite source code contains multiple implementations
5828 ** of these mutex routines. An appropriate implementation
5829 ** is selected automatically at compile-time. The following
5830 ** implementations are available in the SQLite core:
5833 ** <li> SQLITE_MUTEX_OS2
5834 ** <li> SQLITE_MUTEX_PTHREAD
5835 ** <li> SQLITE_MUTEX_W32
5836 ** <li> SQLITE_MUTEX_NOOP
5839 ** The SQLITE_MUTEX_NOOP implementation is a set of routines
5840 ** that does no real locking and is appropriate for use in
5841 ** a single-threaded application. The SQLITE_MUTEX_OS2,
5842 ** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations
5843 ** are appropriate for use on OS/2, Unix, and Windows.
5845 ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
5846 ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
5847 ** implementation is included with the library. In this case the
5848 ** application must supply a custom mutex implementation using the
5849 ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
5850 ** before calling sqlite3_initialize() or any other public sqlite3_
5851 ** function that calls sqlite3_initialize().
5853 ** {H17011} The sqlite3_mutex_alloc() routine allocates a new
5854 ** mutex and returns a pointer to it. {H17012} If it returns NULL
5855 ** that means that a mutex could not be allocated. {H17013} SQLite
5856 ** will unwind its stack and return an error. {H17014} The argument
5857 ** to sqlite3_mutex_alloc() is one of these integer constants:
5860 ** <li> SQLITE_MUTEX_FAST
5861 ** <li> SQLITE_MUTEX_RECURSIVE
5862 ** <li> SQLITE_MUTEX_STATIC_MASTER
5863 ** <li> SQLITE_MUTEX_STATIC_MEM
5864 ** <li> SQLITE_MUTEX_STATIC_MEM2
5865 ** <li> SQLITE_MUTEX_STATIC_PRNG
5866 ** <li> SQLITE_MUTEX_STATIC_LRU
5867 ** <li> SQLITE_MUTEX_STATIC_LRU2
5870 ** {H17015} The first two constants cause sqlite3_mutex_alloc() to create
5871 ** a new mutex. The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
5872 ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. {END}
5873 ** The mutex implementation does not need to make a distinction
5874 ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
5875 ** not want to. {H17016} But SQLite will only request a recursive mutex in
5876 ** cases where it really needs one. {END} If a faster non-recursive mutex
5877 ** implementation is available on the host platform, the mutex subsystem
5878 ** might return such a mutex in response to SQLITE_MUTEX_FAST.
5880 ** {H17017} The other allowed parameters to sqlite3_mutex_alloc() each return
5881 ** a pointer to a static preexisting mutex. {END} Four static mutexes are
5882 ** used by the current version of SQLite. Future versions of SQLite
5883 ** may add additional static mutexes. Static mutexes are for internal
5884 ** use by SQLite only. Applications that use SQLite mutexes should
5885 ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
5886 ** SQLITE_MUTEX_RECURSIVE.
5888 ** {H17018} Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
5889 ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
5890 ** returns a different mutex on every call. {H17034} But for the static
5891 ** mutex types, the same mutex is returned on every call that has
5892 ** the same type number.
5894 ** {H17019} The sqlite3_mutex_free() routine deallocates a previously
5895 ** allocated dynamic mutex. {H17020} SQLite is careful to deallocate every
5896 ** dynamic mutex that it allocates. {A17021} The dynamic mutexes must not be in
5897 ** use when they are deallocated. {A17022} Attempting to deallocate a static
5898 ** mutex results in undefined behavior. {H17023} SQLite never deallocates
5899 ** a static mutex. {END}
5901 ** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
5902 ** to enter a mutex. {H17024} If another thread is already within the mutex,
5903 ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
5904 ** SQLITE_BUSY. {H17025} The sqlite3_mutex_try() interface returns [SQLITE_OK]
5905 ** upon successful entry. {H17026} Mutexes created using
5906 ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
5907 ** {H17027} In such cases the,
5908 ** mutex must be exited an equal number of times before another thread
5909 ** can enter. {A17028} If the same thread tries to enter any other
5910 ** kind of mutex more than once, the behavior is undefined.
5911 ** {H17029} SQLite will never exhibit
5912 ** such behavior in its own use of mutexes.
5914 ** Some systems (for example, Windows 95) do not support the operation
5915 ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
5916 ** will always return SQLITE_BUSY. {H17030} The SQLite core only ever uses
5917 ** sqlite3_mutex_try() as an optimization so this is acceptable behavior.
5919 ** {H17031} The sqlite3_mutex_leave() routine exits a mutex that was
5920 ** previously entered by the same thread. {A17032} The behavior
5921 ** is undefined if the mutex is not currently entered by the
5922 ** calling thread or is not currently allocated. {H17033} SQLite will
5923 ** never do either. {END}
5925 ** If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
5926 ** sqlite3_mutex_leave() is a NULL pointer, then all three routines
5927 ** behave as no-ops.
5929 ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
5931 sqlite3_mutex *sqlite3_mutex_alloc(int);
5932 void sqlite3_mutex_free(sqlite3_mutex*);
5933 void sqlite3_mutex_enter(sqlite3_mutex*);
5934 int sqlite3_mutex_try(sqlite3_mutex*);
5935 void sqlite3_mutex_leave(sqlite3_mutex*);
5938 ** CAPI3REF: Mutex Methods Object {H17120} <S20130>
5941 ** An instance of this structure defines the low-level routines
5942 ** used to allocate and use mutexes.
5944 ** Usually, the default mutex implementations provided by SQLite are
5945 ** sufficient, however the user has the option of substituting a custom
5946 ** implementation for specialized deployments or systems for which SQLite
5947 ** does not provide a suitable implementation. In this case, the user
5948 ** creates and populates an instance of this structure to pass
5949 ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
5950 ** Additionally, an instance of this structure can be used as an
5951 ** output variable when querying the system for the current mutex
5952 ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
5954 ** The xMutexInit method defined by this structure is invoked as
5955 ** part of system initialization by the sqlite3_initialize() function.
5956 ** {H17001} The xMutexInit routine shall be called by SQLite once for each
5957 ** effective call to [sqlite3_initialize()].
5959 ** The xMutexEnd method defined by this structure is invoked as
5960 ** part of system shutdown by the sqlite3_shutdown() function. The
5961 ** implementation of this method is expected to release all outstanding
5962 ** resources obtained by the mutex methods implementation, especially
5963 ** those obtained by the xMutexInit method. {H17003} The xMutexEnd()
5964 ** interface shall be invoked once for each call to [sqlite3_shutdown()].
5966 ** The remaining seven methods defined by this structure (xMutexAlloc,
5967 ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
5968 ** xMutexNotheld) implement the following interfaces (respectively):
5971 ** <li> [sqlite3_mutex_alloc()] </li>
5972 ** <li> [sqlite3_mutex_free()] </li>
5973 ** <li> [sqlite3_mutex_enter()] </li>
5974 ** <li> [sqlite3_mutex_try()] </li>
5975 ** <li> [sqlite3_mutex_leave()] </li>
5976 ** <li> [sqlite3_mutex_held()] </li>
5977 ** <li> [sqlite3_mutex_notheld()] </li>
5980 ** The only difference is that the public sqlite3_XXX functions enumerated
5981 ** above silently ignore any invocations that pass a NULL pointer instead
5982 ** of a valid mutex handle. The implementations of the methods defined
5983 ** by this structure are not required to handle this case, the results
5984 ** of passing a NULL pointer instead of a valid mutex handle are undefined
5985 ** (i.e. it is acceptable to provide an implementation that segfaults if
5986 ** it is passed a NULL pointer).
5988 typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
5989 struct sqlite3_mutex_methods {
5990 int (*xMutexInit)(void);
5991 int (*xMutexEnd)(void);
5992 sqlite3_mutex *(*xMutexAlloc)(int);
5993 void (*xMutexFree)(sqlite3_mutex *);
5994 void (*xMutexEnter)(sqlite3_mutex *);
5995 int (*xMutexTry)(sqlite3_mutex *);
5996 void (*xMutexLeave)(sqlite3_mutex *);
5997 int (*xMutexHeld)(sqlite3_mutex *);
5998 int (*xMutexNotheld)(sqlite3_mutex *);
6002 ** CAPI3REF: Mutex Verification Routines {H17080} <S20130> <S30800>
6004 ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
6005 ** are intended for use inside assert() statements. {H17081} The SQLite core
6006 ** never uses these routines except inside an assert() and applications
6007 ** are advised to follow the lead of the core. {H17082} The core only
6008 ** provides implementations for these routines when it is compiled
6009 ** with the SQLITE_DEBUG flag. {A17087} External mutex implementations
6010 ** are only required to provide these routines if SQLITE_DEBUG is
6011 ** defined and if NDEBUG is not defined.
6013 ** {H17083} These routines should return true if the mutex in their argument
6014 ** is held or not held, respectively, by the calling thread.
6016 ** {X17084} The implementation is not required to provided versions of these
6017 ** routines that actually work. If the implementation does not provide working
6018 ** versions of these routines, it should at least provide stubs that always
6019 ** return true so that one does not get spurious assertion failures.
6021 ** {H17085} If the argument to sqlite3_mutex_held() is a NULL pointer then
6022 ** the routine should return 1. {END} This seems counter-intuitive since
6023 ** clearly the mutex cannot be held if it does not exist. But the
6024 ** the reason the mutex does not exist is because the build is not
6025 ** using mutexes. And we do not want the assert() containing the
6026 ** call to sqlite3_mutex_held() to fail, so a non-zero return is
6027 ** the appropriate thing to do. {H17086} The sqlite3_mutex_notheld()
6028 ** interface should also return 1 when given a NULL pointer.
6030 int sqlite3_mutex_held(sqlite3_mutex*);
6031 int sqlite3_mutex_notheld(sqlite3_mutex*);
6034 ** CAPI3REF: Mutex Types {H17001} <H17000>
6036 ** The [sqlite3_mutex_alloc()] interface takes a single argument
6037 ** which is one of these integer constants.
6039 ** The set of static mutexes may change from one SQLite release to the
6040 ** next. Applications that override the built-in mutex logic must be
6041 ** prepared to accommodate additional static mutexes.
6043 #define SQLITE_MUTEX_FAST 0
6044 #define SQLITE_MUTEX_RECURSIVE 1
6045 #define SQLITE_MUTEX_STATIC_MASTER 2
6046 #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
6047 #define SQLITE_MUTEX_STATIC_MEM2 4 /* sqlite3_release_memory() */
6048 #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
6049 #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
6050 #define SQLITE_MUTEX_STATIC_LRU2 7 /* lru page list */
6053 ** CAPI3REF: Low-Level Control Of Database Files {H11300} <S30800>
6055 ** {H11301} The [sqlite3_file_control()] interface makes a direct call to the
6056 ** xFileControl method for the [sqlite3_io_methods] object associated
6057 ** with a particular database identified by the second argument. {H11302} The
6058 ** name of the database is the name assigned to the database by the
6059 ** <a href="lang_attach.html">ATTACH</a> SQL command that opened the
6060 ** database. {H11303} To control the main database file, use the name "main"
6061 ** or a NULL pointer. {H11304} The third and fourth parameters to this routine
6062 ** are passed directly through to the second and third parameters of
6063 ** the xFileControl method. {H11305} The return value of the xFileControl
6064 ** method becomes the return value of this routine.
6066 ** {H11306} If the second parameter (zDbName) does not match the name of any
6067 ** open database file, then SQLITE_ERROR is returned. {H11307} This error
6068 ** code is not remembered and will not be recalled by [sqlite3_errcode()]
6069 ** or [sqlite3_errmsg()]. {A11308} The underlying xFileControl method might
6070 ** also return SQLITE_ERROR. {A11309} There is no way to distinguish between
6071 ** an incorrect zDbName and an SQLITE_ERROR return from the underlying
6072 ** xFileControl method. {END}
6074 ** See also: [SQLITE_FCNTL_LOCKSTATE]
6076 int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
6079 ** CAPI3REF: Testing Interface {H11400} <S30800>
6081 ** The sqlite3_test_control() interface is used to read out internal
6082 ** state of SQLite and to inject faults into SQLite for testing
6083 ** purposes. The first parameter is an operation code that determines
6084 ** the number, meaning, and operation of all subsequent parameters.
6086 ** This interface is not for use by applications. It exists solely
6087 ** for verifying the correct operation of the SQLite library. Depending
6088 ** on how the SQLite library is compiled, this interface might not exist.
6090 ** The details of the operation codes, their meanings, the parameters
6091 ** they take, and what they do are all subject to change without notice.
6092 ** Unlike most of the SQLite API, this function is not guaranteed to
6093 ** operate consistently from one release to the next.
6095 int sqlite3_test_control(int op, ...);
6098 ** CAPI3REF: Testing Interface Operation Codes {H11410} <H11400>
6100 ** These constants are the valid operation code parameters used
6101 ** as the first argument to [sqlite3_test_control()].
6103 ** These parameters and their meanings are subject to change
6104 ** without notice. These values are for testing purposes only.
6105 ** Applications should not use any of these parameters or the
6106 ** [sqlite3_test_control()] interface.
6108 #define SQLITE_TESTCTRL_PRNG_SAVE 5
6109 #define SQLITE_TESTCTRL_PRNG_RESTORE 6
6110 #define SQLITE_TESTCTRL_PRNG_RESET 7
6111 #define SQLITE_TESTCTRL_BITVEC_TEST 8
6112 #define SQLITE_TESTCTRL_FAULT_INSTALL 9
6113 #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
6116 ** CAPI3REF: SQLite Runtime Status {H17200} <S60200>
6119 ** This interface is used to retrieve runtime status information
6120 ** about the preformance of SQLite, and optionally to reset various
6121 ** highwater marks. The first argument is an integer code for
6122 ** the specific parameter to measure. Recognized integer codes
6123 ** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...].
6124 ** The current value of the parameter is returned into *pCurrent.
6125 ** The highest recorded value is returned in *pHighwater. If the
6126 ** resetFlag is true, then the highest record value is reset after
6127 ** *pHighwater is written. Some parameters do not record the highest
6128 ** value. For those parameters
6129 ** nothing is written into *pHighwater and the resetFlag is ignored.
6130 ** Other parameters record only the highwater mark and not the current
6131 ** value. For these latter parameters nothing is written into *pCurrent.
6133 ** This routine returns SQLITE_OK on success and a non-zero
6134 ** [error code] on failure.
6136 ** This routine is threadsafe but is not atomic. This routine can
6137 ** called while other threads are running the same or different SQLite
6138 ** interfaces. However the values returned in *pCurrent and
6139 ** *pHighwater reflect the status of SQLite at different points in time
6140 ** and it is possible that another thread might change the parameter
6141 ** in between the times when *pCurrent and *pHighwater are written.
6143 ** See also: [sqlite3_db_status()]
6145 int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
6148 ** CAPI3REF: Database Connection Status {H17201} <S60200>
6151 ** This interface is used to retrieve runtime status information
6152 ** about a single [database connection]. The first argument is the
6153 ** database connection object to be interrogated. The second argument
6154 ** is the parameter to interrogate. Currently, the only allowed value
6155 ** for the second parameter is [SQLITE_DBSTATUS_LOOKASIDE_USED].
6156 ** Additional options will likely appear in future releases of SQLite.
6158 ** The current value of the request parameter is written into *pCur
6159 ** and the highest instantaneous value is written into *pHiwtr. If
6160 ** the resetFlg is true, then the highest instantaneous value is
6161 ** reset back down to the current value.
6163 ** See also: [sqlite3_status()].
6165 int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
6168 ** CAPI3REF: Status Parameters {H17250} <H17200>
6171 ** These integer constants designate various run-time status parameters
6172 ** that can be returned by [sqlite3_status()].
6175 ** <dt>SQLITE_STATUS_MEMORY_USED</dt>
6176 ** <dd>This parameter is the current amount of memory checked out
6177 ** using [sqlite3_malloc()], either directly or indirectly. The
6178 ** figure includes calls made to [sqlite3_malloc()] by the application
6179 ** and internal memory usage by the SQLite library. Scratch memory
6180 ** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
6181 ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
6182 ** this parameter. The amount returned is the sum of the allocation
6183 ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>
6185 ** <dt>SQLITE_STATUS_MALLOC_SIZE</dt>
6186 ** <dd>This parameter records the largest memory allocation request
6187 ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
6188 ** internal equivalents). Only the value returned in the
6189 ** *pHighwater parameter to [sqlite3_status()] is of interest.
6190 ** The value written into the *pCurrent parameter is undefined.</dd>
6192 ** <dt>SQLITE_STATUS_PAGECACHE_USED</dt>
6193 ** <dd>This parameter returns the number of pages used out of the
6194 ** [pagecache memory allocator] that was configured using
6195 ** [SQLITE_CONFIG_PAGECACHE]. The
6196 ** value returned is in pages, not in bytes.</dd>
6198 ** <dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
6199 ** <dd>This parameter returns the number of bytes of page cache
6200 ** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE]
6201 ** buffer and where forced to overflow to [sqlite3_malloc()]. The
6202 ** returned value includes allocations that overflowed because they
6203 ** where too large (they were larger than the "sz" parameter to
6204 ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
6205 ** no space was left in the page cache.</dd>
6207 ** <dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
6208 ** <dd>This parameter records the largest memory allocation request
6209 ** handed to [pagecache memory allocator]. Only the value returned in the
6210 ** *pHighwater parameter to [sqlite3_status()] is of interest.
6211 ** The value written into the *pCurrent parameter is undefined.</dd>
6213 ** <dt>SQLITE_STATUS_SCRATCH_USED</dt>
6214 ** <dd>This parameter returns the number of allocations used out of the
6215 ** [scratch memory allocator] configured using
6216 ** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not
6217 ** in bytes. Since a single thread may only have one scratch allocation
6218 ** outstanding at time, this parameter also reports the number of threads
6219 ** using scratch memory at the same time.</dd>
6221 ** <dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
6222 ** <dd>This parameter returns the number of bytes of scratch memory
6223 ** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH]
6224 ** buffer and where forced to overflow to [sqlite3_malloc()]. The values
6225 ** returned include overflows because the requested allocation was too
6226 ** larger (that is, because the requested allocation was larger than the
6227 ** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
6228 ** slots were available.
6231 ** <dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
6232 ** <dd>This parameter records the largest memory allocation request
6233 ** handed to [scratch memory allocator]. Only the value returned in the
6234 ** *pHighwater parameter to [sqlite3_status()] is of interest.
6235 ** The value written into the *pCurrent parameter is undefined.</dd>
6237 ** <dt>SQLITE_STATUS_PARSER_STACK</dt>
6238 ** <dd>This parameter records the deepest parser stack. It is only
6239 ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>
6242 ** New status parameters may be added from time to time.
6244 #define SQLITE_STATUS_MEMORY_USED 0
6245 #define SQLITE_STATUS_PAGECACHE_USED 1
6246 #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
6247 #define SQLITE_STATUS_SCRATCH_USED 3
6248 #define SQLITE_STATUS_SCRATCH_OVERFLOW 4
6249 #define SQLITE_STATUS_MALLOC_SIZE 5
6250 #define SQLITE_STATUS_PARSER_STACK 6
6251 #define SQLITE_STATUS_PAGECACHE_SIZE 7
6252 #define SQLITE_STATUS_SCRATCH_SIZE 8
6255 ** CAPI3REF: Status Parameters for database connections {H17275} <H17200>
6258 ** Status verbs for [sqlite3_db_status()].
6261 ** <dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
6262 ** <dd>This parameter returns the number of lookaside memory slots currently
6263 ** checked out.</dd>
6266 #define SQLITE_DBSTATUS_LOOKASIDE_USED 0
6269 ** Undo the hack that converts floating point types to integer for
6270 ** builds on processors without floating point support.
6272 #ifdef SQLITE_OMIT_FLOATING_POINT
6277 } /* End of the 'extern "C"' block */