1 /******************************************************************************
2 ** This file is an amalgamation of many separate C source files from SQLite
3 ** version 3.11.0. By combining all the individual C code files into this
4 ** single large file, the entire code can be compiled as a single translation
5 ** unit. This allows many compilers to do optimizations that would not be
6 ** possible if the files were compiled separately. Performance improvements
7 ** of 5% or more are commonly seen when SQLite is compiled as a single
10 ** This file is all you need to compile SQLite. To use SQLite in other
11 ** programs, you need this file and the "sqlite3.h" header file that defines
12 ** the programming interface to the SQLite library. (If you do not have
13 ** the "sqlite3.h" header file at hand, you will find a copy embedded within
14 ** the text of this file. Search for "Begin file sqlite3.h" to find the start
15 ** of the embedded sqlite3.h header file.) Additional code files may be needed
16 ** if you want a wrapper to interface SQLite with your choice of programming
17 ** language. The code for the "sqlite3" command-line shell is also in a
18 ** separate file. This file contains only code for the core SQLite library.
21 #define SQLITE_AMALGAMATION 1
22 #ifndef SQLITE_PRIVATE
23 # define SQLITE_PRIVATE static
25 /************** Begin file sqliteInt.h ***************************************/
29 ** The author disclaims copyright to this source code. In place of
30 ** a legal notice, here is a blessing:
32 ** May you do good and not evil.
33 ** May you find forgiveness for yourself and forgive others.
34 ** May you share freely, never taking more than you give.
36 *************************************************************************
37 ** Internal interface definitions for SQLite.
44 ** Include the header file used to customize the compiler options for MSVC.
45 ** This should be done first so that it can successfully prevent spurious
46 ** compiler warnings due to subsequent content in this file and other files
47 ** that are included by this file.
49 /************** Include msvc.h in the middle of sqliteInt.h ******************/
50 /************** Begin file msvc.h ********************************************/
54 ** The author disclaims copyright to this source code. In place of
55 ** a legal notice, here is a blessing:
57 ** May you do good and not evil.
58 ** May you find forgiveness for yourself and forgive others.
59 ** May you share freely, never taking more than you give.
61 ******************************************************************************
63 ** This file contains code that is specific to MSVC.
69 #pragma warning(disable : 4054)
70 #pragma warning(disable : 4055)
71 #pragma warning(disable : 4100)
72 #pragma warning(disable : 4127)
73 #pragma warning(disable : 4130)
74 #pragma warning(disable : 4152)
75 #pragma warning(disable : 4189)
76 #pragma warning(disable : 4206)
77 #pragma warning(disable : 4210)
78 #pragma warning(disable : 4232)
79 #pragma warning(disable : 4244)
80 #pragma warning(disable : 4305)
81 #pragma warning(disable : 4306)
82 #pragma warning(disable : 4702)
83 #pragma warning(disable : 4706)
84 #endif /* defined(_MSC_VER) */
88 /************** End of msvc.h ************************************************/
89 /************** Continuing where we left off in sqliteInt.h ******************/
92 ** Special setup for VxWorks
94 /************** Include vxworks.h in the middle of sqliteInt.h ***************/
95 /************** Begin file vxworks.h *****************************************/
99 ** The author disclaims copyright to this source code. In place of
100 ** a legal notice, here is a blessing:
102 ** May you do good and not evil.
103 ** May you find forgiveness for yourself and forgive others.
104 ** May you share freely, never taking more than you give.
106 ******************************************************************************
108 ** This file contains code that is specific to Wind River's VxWorks
110 #if defined(__RTP__) || defined(_WRS_KERNEL)
111 /* This is VxWorks. Set up things specially for that OS
114 #include <pthread.h> /* amalgamator: dontcache */
116 #define SQLITE_OS_OTHER 0
117 #define SQLITE_HOMEGROWN_RECURSIVE_MUTEX 1
118 #define SQLITE_OMIT_LOAD_EXTENSION 1
119 #define SQLITE_ENABLE_LOCKING_STYLE 0
122 /* This is not VxWorks. */
124 #define HAVE_FCHOWN 1
125 #define HAVE_READLINK 1
127 #endif /* defined(_WRS_KERNEL) */
129 /************** End of vxworks.h *********************************************/
130 /************** Continuing where we left off in sqliteInt.h ******************/
133 ** These #defines should enable >2GB file support on POSIX if the
134 ** underlying operating system supports it. If the OS lacks
135 ** large file support, or if the OS is windows, these should be no-ops.
137 ** Ticket #2739: The _LARGEFILE_SOURCE macro must appear before any
138 ** system #includes. Hence, this block of code must be the very first
139 ** code in all source files.
141 ** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
142 ** on the compiler command line. This is necessary if you are compiling
143 ** on a recent machine (ex: Red Hat 7.2) but you want your code to work
144 ** on an older machine (ex: Red Hat 6.0). If you compile on Red Hat 7.2
145 ** without this option, LFS is enable. But LFS does not exist in the kernel
146 ** in Red Hat 6.0, so the code won't work. Hence, for maximum binary
147 ** portability you should omit LFS.
149 ** The previous paragraph was written in 2005. (This paragraph is written
150 ** on 2008-11-28.) These days, all Linux kernels support large files, so
151 ** you should probably leave LFS enabled. But some embedded platforms might
152 ** lack LFS in which case the SQLITE_DISABLE_LFS macro might still be useful.
154 ** Similar is true for Mac OS X. LFS is only supported on Mac OS X 9 and later.
156 #ifndef SQLITE_DISABLE_LFS
157 # define _LARGE_FILE 1
158 # ifndef _FILE_OFFSET_BITS
159 # define _FILE_OFFSET_BITS 64
161 # define _LARGEFILE_SOURCE 1
164 /* What version of GCC is being used. 0 means GCC is not being used */
166 # define GCC_VERSION (__GNUC__*1000000+__GNUC_MINOR__*1000+__GNUC_PATCHLEVEL__)
168 # define GCC_VERSION 0
171 /* Needed for various definitions... */
172 #if defined(__GNUC__) && !defined(_GNU_SOURCE)
176 #if defined(__OpenBSD__) && !defined(_BSD_SOURCE)
181 ** For MinGW, check to see if we can include the header file containing its
182 ** version information, among other things. Normally, this internal MinGW
183 ** header file would [only] be included automatically by other MinGW header
184 ** files; however, the contained version information is now required by this
185 ** header file to work around binary compatibility issues (see below) and
186 ** this is the only known way to reliably obtain it. This entire #if block
187 ** would be completely unnecessary if there was any other way of detecting
188 ** MinGW via their preprocessor (e.g. if they customized their GCC to define
189 ** some MinGW-specific macros). When compiling for MinGW, either the
190 ** _HAVE_MINGW_H or _HAVE__MINGW_H (note the extra underscore) macro must be
191 ** defined; otherwise, detection of conditions specific to MinGW will be
194 #if defined(_HAVE_MINGW_H)
196 #elif defined(_HAVE__MINGW_H)
201 ** For MinGW version 4.x (and higher), check to see if the _USE_32BIT_TIME_T
202 ** define is required to maintain binary compatibility with the MSVC runtime
203 ** library in use (e.g. for Windows XP).
205 #if !defined(_USE_32BIT_TIME_T) && !defined(_USE_64BIT_TIME_T) && \
206 defined(_WIN32) && !defined(_WIN64) && \
207 defined(__MINGW_MAJOR_VERSION) && __MINGW_MAJOR_VERSION >= 4 && \
209 # define _USE_32BIT_TIME_T
212 /* The public SQLite interface. The _FILE_OFFSET_BITS macro must appear
213 ** first in QNX. Also, the _USE_32BIT_TIME_T macro must appear first for
216 /************** Include sqlite3.h in the middle of sqliteInt.h ***************/
217 /************** Begin file sqlite3.h *****************************************/
221 ** The author disclaims copyright to this source code. In place of
222 ** a legal notice, here is a blessing:
224 ** May you do good and not evil.
225 ** May you find forgiveness for yourself and forgive others.
226 ** May you share freely, never taking more than you give.
228 *************************************************************************
229 ** This header file defines the interface that the SQLite library
230 ** presents to client programs. If a C-function, structure, datatype,
231 ** or constant definition does not appear in this file, then it is
232 ** not a published API of SQLite, is subject to change without
233 ** notice, and should not be referenced by programs that use SQLite.
235 ** Some of the definitions that are in this file are marked as
236 ** "experimental". Experimental interfaces are normally new
237 ** features recently added to SQLite. We do not anticipate changes
238 ** to experimental interfaces but reserve the right to make minor changes
239 ** if experience from use "in the wild" suggest such changes are prudent.
241 ** The official C-language API documentation for SQLite is derived
242 ** from comments in this file. This file is the authoritative source
243 ** on how SQLite interfaces are supposed to operate.
245 ** The name of this file under configuration management is "sqlite.h.in".
246 ** The makefile makes some minor changes to this file (such as inserting
247 ** the version number) and changes its name to "sqlite3.h" as
248 ** part of the build process.
252 #include <stdarg.h> /* Needed for the definition of va_list */
255 ** Make sure we can call this stuff from C++.
263 ** Provide the ability to override linkage features of the interface.
265 #ifndef SQLITE_EXTERN
266 # define SQLITE_EXTERN extern
272 # define SQLITE_CDECL
274 #ifndef SQLITE_STDCALL
275 # define SQLITE_STDCALL
279 ** These no-op macros are used in front of interfaces to mark those
280 ** interfaces as either deprecated or experimental. New applications
281 ** should not use deprecated interfaces - they are supported for backwards
282 ** compatibility only. Application writers should be aware that
283 ** experimental interfaces are subject to change in point releases.
285 ** These macros used to resolve to various kinds of compiler magic that
286 ** would generate warning messages when they were used. But that
287 ** compiler magic ended up generating such a flurry of bug reports
288 ** that we have taken it all out and gone back to using simple
291 #define SQLITE_DEPRECATED
292 #define SQLITE_EXPERIMENTAL
295 ** Ensure these symbols were not defined by some previous header file.
297 #ifdef SQLITE_VERSION
298 # undef SQLITE_VERSION
300 #ifdef SQLITE_VERSION_NUMBER
301 # undef SQLITE_VERSION_NUMBER
305 ** CAPI3REF: Compile-Time Library Version Numbers
307 ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
308 ** evaluates to a string literal that is the SQLite version in the
309 ** format "X.Y.Z" where X is the major version number (always 3 for
310 ** SQLite3) and Y is the minor version number and Z is the release number.)^
311 ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
312 ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
313 ** numbers used in [SQLITE_VERSION].)^
314 ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
315 ** be larger than the release from which it is derived. Either Y will
316 ** be held constant and Z will be incremented or else Y will be incremented
317 ** and Z will be reset to zero.
319 ** Since version 3.6.18, SQLite source code has been stored in the
320 ** <a href="http://www.fossil-scm.org/">Fossil configuration management
321 ** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to
322 ** a string which identifies a particular check-in of SQLite
323 ** within its configuration management system. ^The SQLITE_SOURCE_ID
324 ** string contains the date and time of the check-in (UTC) and an SHA1
325 ** hash of the entire source tree.
327 ** See also: [sqlite3_libversion()],
328 ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
329 ** [sqlite_version()] and [sqlite_source_id()].
331 #define SQLITE_VERSION "3.11.0"
332 #define SQLITE_VERSION_NUMBER 3011000
333 #define SQLITE_SOURCE_ID "2016-02-15 17:29:24 3d862f207e3adc00f78066799ac5a8c282430a5f"
336 ** CAPI3REF: Run-Time Library Version Numbers
337 ** KEYWORDS: sqlite3_version, sqlite3_sourceid
339 ** These interfaces provide the same information as the [SQLITE_VERSION],
340 ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
341 ** but are associated with the library instead of the header file. ^(Cautious
342 ** programmers might include assert() statements in their application to
343 ** verify that values returned by these interfaces match the macros in
344 ** the header, and thus ensure that the application is
345 ** compiled with matching library and header files.
348 ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
349 ** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
350 ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
351 ** </pre></blockquote>)^
353 ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
354 ** macro. ^The sqlite3_libversion() function returns a pointer to the
355 ** to the sqlite3_version[] string constant. The sqlite3_libversion()
356 ** function is provided for use in DLLs since DLL users usually do not have
357 ** direct access to string constants within the DLL. ^The
358 ** sqlite3_libversion_number() function returns an integer equal to
359 ** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns
360 ** a pointer to a string constant whose value is the same as the
361 ** [SQLITE_SOURCE_ID] C preprocessor macro.
363 ** See also: [sqlite_version()] and [sqlite_source_id()].
365 SQLITE_API const char sqlite3_version[] = SQLITE_VERSION;
366 SQLITE_API const char *SQLITE_STDCALL sqlite3_libversion(void);
367 SQLITE_API const char *SQLITE_STDCALL sqlite3_sourceid(void);
368 SQLITE_API int SQLITE_STDCALL sqlite3_libversion_number(void);
371 ** CAPI3REF: Run-Time Library Compilation Options Diagnostics
373 ** ^The sqlite3_compileoption_used() function returns 0 or 1
374 ** indicating whether the specified option was defined at
375 ** compile time. ^The SQLITE_ prefix may be omitted from the
376 ** option name passed to sqlite3_compileoption_used().
378 ** ^The sqlite3_compileoption_get() function allows iterating
379 ** over the list of options that were defined at compile time by
380 ** returning the N-th compile time option string. ^If N is out of range,
381 ** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
382 ** prefix is omitted from any strings returned by
383 ** sqlite3_compileoption_get().
385 ** ^Support for the diagnostic functions sqlite3_compileoption_used()
386 ** and sqlite3_compileoption_get() may be omitted by specifying the
387 ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
389 ** See also: SQL functions [sqlite_compileoption_used()] and
390 ** [sqlite_compileoption_get()] and the [compile_options pragma].
392 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
393 SQLITE_API int SQLITE_STDCALL sqlite3_compileoption_used(const char *zOptName);
394 SQLITE_API const char *SQLITE_STDCALL sqlite3_compileoption_get(int N);
398 ** CAPI3REF: Test To See If The Library Is Threadsafe
400 ** ^The sqlite3_threadsafe() function returns zero if and only if
401 ** SQLite was compiled with mutexing code omitted due to the
402 ** [SQLITE_THREADSAFE] compile-time option being set to 0.
404 ** SQLite can be compiled with or without mutexes. When
405 ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
406 ** are enabled and SQLite is threadsafe. When the
407 ** [SQLITE_THREADSAFE] macro is 0,
408 ** the mutexes are omitted. Without the mutexes, it is not safe
409 ** to use SQLite concurrently from more than one thread.
411 ** Enabling mutexes incurs a measurable performance penalty.
412 ** So if speed is of utmost importance, it makes sense to disable
413 ** the mutexes. But for maximum safety, mutexes should be enabled.
414 ** ^The default behavior is for mutexes to be enabled.
416 ** This interface can be used by an application to make sure that the
417 ** version of SQLite that it is linking against was compiled with
418 ** the desired setting of the [SQLITE_THREADSAFE] macro.
420 ** This interface only reports on the compile-time mutex setting
421 ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
422 ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
423 ** can be fully or partially disabled using a call to [sqlite3_config()]
424 ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
425 ** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the
426 ** sqlite3_threadsafe() function shows only the compile-time setting of
427 ** thread safety, not any run-time changes to that setting made by
428 ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
429 ** is unchanged by calls to sqlite3_config().)^
431 ** See the [threading mode] documentation for additional information.
433 SQLITE_API int SQLITE_STDCALL sqlite3_threadsafe(void);
436 ** CAPI3REF: Database Connection Handle
437 ** KEYWORDS: {database connection} {database connections}
439 ** Each open SQLite database is represented by a pointer to an instance of
440 ** the opaque structure named "sqlite3". It is useful to think of an sqlite3
441 ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
442 ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
443 ** and [sqlite3_close_v2()] are its destructors. There are many other
444 ** interfaces (such as
445 ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
446 ** [sqlite3_busy_timeout()] to name but three) that are methods on an
449 typedef struct sqlite3 sqlite3;
452 ** CAPI3REF: 64-Bit Integer Types
453 ** KEYWORDS: sqlite_int64 sqlite_uint64
455 ** Because there is no cross-platform way to specify 64-bit integer types
456 ** SQLite includes typedefs for 64-bit signed and unsigned integers.
458 ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
459 ** The sqlite_int64 and sqlite_uint64 types are supported for backwards
460 ** compatibility only.
462 ** ^The sqlite3_int64 and sqlite_int64 types can store integer values
463 ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
464 ** sqlite3_uint64 and sqlite_uint64 types can store integer values
465 ** between 0 and +18446744073709551615 inclusive.
467 #ifdef SQLITE_INT64_TYPE
468 typedef SQLITE_INT64_TYPE sqlite_int64;
469 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
470 #elif defined(_MSC_VER) || defined(__BORLANDC__)
471 typedef __int64 sqlite_int64;
472 typedef unsigned __int64 sqlite_uint64;
474 typedef long long int sqlite_int64;
475 typedef unsigned long long int sqlite_uint64;
477 typedef sqlite_int64 sqlite3_int64;
478 typedef sqlite_uint64 sqlite3_uint64;
481 ** If compiling for a processor that lacks floating point support,
482 ** substitute integer for floating-point.
484 #ifdef SQLITE_OMIT_FLOATING_POINT
485 # define double sqlite3_int64
489 ** CAPI3REF: Closing A Database Connection
490 ** DESTRUCTOR: sqlite3
492 ** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
493 ** for the [sqlite3] object.
494 ** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
495 ** the [sqlite3] object is successfully destroyed and all associated
496 ** resources are deallocated.
498 ** ^If the database connection is associated with unfinalized prepared
499 ** statements or unfinished sqlite3_backup objects then sqlite3_close()
500 ** will leave the database connection open and return [SQLITE_BUSY].
501 ** ^If sqlite3_close_v2() is called with unfinalized prepared statements
502 ** and/or unfinished sqlite3_backups, then the database connection becomes
503 ** an unusable "zombie" which will automatically be deallocated when the
504 ** last prepared statement is finalized or the last sqlite3_backup is
505 ** finished. The sqlite3_close_v2() interface is intended for use with
506 ** host languages that are garbage collected, and where the order in which
507 ** destructors are called is arbitrary.
509 ** Applications should [sqlite3_finalize | finalize] all [prepared statements],
510 ** [sqlite3_blob_close | close] all [BLOB handles], and
511 ** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
512 ** with the [sqlite3] object prior to attempting to close the object. ^If
513 ** sqlite3_close_v2() is called on a [database connection] that still has
514 ** outstanding [prepared statements], [BLOB handles], and/or
515 ** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation
516 ** of resources is deferred until all [prepared statements], [BLOB handles],
517 ** and [sqlite3_backup] objects are also destroyed.
519 ** ^If an [sqlite3] object is destroyed while a transaction is open,
520 ** the transaction is automatically rolled back.
522 ** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
523 ** must be either a NULL
524 ** pointer or an [sqlite3] object pointer obtained
525 ** from [sqlite3_open()], [sqlite3_open16()], or
526 ** [sqlite3_open_v2()], and not previously closed.
527 ** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
528 ** argument is a harmless no-op.
530 SQLITE_API int SQLITE_STDCALL sqlite3_close(sqlite3*);
531 SQLITE_API int SQLITE_STDCALL sqlite3_close_v2(sqlite3*);
534 ** The type for a callback function.
535 ** This is legacy and deprecated. It is included for historical
536 ** compatibility and is not documented.
538 typedef int (*sqlite3_callback)(void*,int,char**, char**);
541 ** CAPI3REF: One-Step Query Execution Interface
544 ** The sqlite3_exec() interface is a convenience wrapper around
545 ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
546 ** that allows an application to run multiple statements of SQL
547 ** without having to use a lot of C code.
549 ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
550 ** semicolon-separate SQL statements passed into its 2nd argument,
551 ** in the context of the [database connection] passed in as its 1st
552 ** argument. ^If the callback function of the 3rd argument to
553 ** sqlite3_exec() is not NULL, then it is invoked for each result row
554 ** coming out of the evaluated SQL statements. ^The 4th argument to
555 ** sqlite3_exec() is relayed through to the 1st argument of each
556 ** callback invocation. ^If the callback pointer to sqlite3_exec()
557 ** is NULL, then no callback is ever invoked and result rows are
560 ** ^If an error occurs while evaluating the SQL statements passed into
561 ** sqlite3_exec(), then execution of the current statement stops and
562 ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
563 ** is not NULL then any error message is written into memory obtained
564 ** from [sqlite3_malloc()] and passed back through the 5th parameter.
565 ** To avoid memory leaks, the application should invoke [sqlite3_free()]
566 ** on error message strings returned through the 5th parameter of
567 ** sqlite3_exec() after the error message string is no longer needed.
568 ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
569 ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
570 ** NULL before returning.
572 ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
573 ** routine returns SQLITE_ABORT without invoking the callback again and
574 ** without running any subsequent SQL statements.
576 ** ^The 2nd argument to the sqlite3_exec() callback function is the
577 ** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
578 ** callback is an array of pointers to strings obtained as if from
579 ** [sqlite3_column_text()], one for each column. ^If an element of a
580 ** result row is NULL then the corresponding string pointer for the
581 ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
582 ** sqlite3_exec() callback is an array of pointers to strings where each
583 ** entry represents the name of corresponding result column as obtained
584 ** from [sqlite3_column_name()].
586 ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
587 ** to an empty string, or a pointer that contains only whitespace and/or
588 ** SQL comments, then no SQL statements are evaluated and the database
594 ** <li> The application must ensure that the 1st parameter to sqlite3_exec()
595 ** is a valid and open [database connection].
596 ** <li> The application must not close the [database connection] specified by
597 ** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
598 ** <li> The application must not modify the SQL statement text passed into
599 ** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
602 SQLITE_API int SQLITE_STDCALL sqlite3_exec(
603 sqlite3*, /* An open database */
604 const char *sql, /* SQL to be evaluated */
605 int (*callback)(void*,int,char**,char**), /* Callback function */
606 void *, /* 1st argument to callback */
607 char **errmsg /* Error msg written here */
611 ** CAPI3REF: Result Codes
612 ** KEYWORDS: {result code definitions}
614 ** Many SQLite functions return an integer result code from the set shown
615 ** here in order to indicate success or failure.
617 ** New error codes may be added in future versions of SQLite.
619 ** See also: [extended result code definitions]
621 #define SQLITE_OK 0 /* Successful result */
622 /* beginning-of-error-codes */
623 #define SQLITE_ERROR 1 /* SQL error or missing database */
624 #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
625 #define SQLITE_PERM 3 /* Access permission denied */
626 #define SQLITE_ABORT 4 /* Callback routine requested an abort */
627 #define SQLITE_BUSY 5 /* The database file is locked */
628 #define SQLITE_LOCKED 6 /* A table in the database is locked */
629 #define SQLITE_NOMEM 7 /* A malloc() failed */
630 #define SQLITE_READONLY 8 /* Attempt to write a readonly database */
631 #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
632 #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
633 #define SQLITE_CORRUPT 11 /* The database disk image is malformed */
634 #define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */
635 #define SQLITE_FULL 13 /* Insertion failed because database is full */
636 #define SQLITE_CANTOPEN 14 /* Unable to open the database file */
637 #define SQLITE_PROTOCOL 15 /* Database lock protocol error */
638 #define SQLITE_EMPTY 16 /* Database is empty */
639 #define SQLITE_SCHEMA 17 /* The database schema changed */
640 #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
641 #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
642 #define SQLITE_MISMATCH 20 /* Data type mismatch */
643 #define SQLITE_MISUSE 21 /* Library used incorrectly */
644 #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
645 #define SQLITE_AUTH 23 /* Authorization denied */
646 #define SQLITE_FORMAT 24 /* Auxiliary database format error */
647 #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
648 #define SQLITE_NOTADB 26 /* File opened that is not a database file */
649 #define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */
650 #define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */
651 #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
652 #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
653 /* end-of-error-codes */
656 ** CAPI3REF: Extended Result Codes
657 ** KEYWORDS: {extended result code definitions}
659 ** In its default configuration, SQLite API routines return one of 30 integer
660 ** [result codes]. However, experience has shown that many of
661 ** these result codes are too coarse-grained. They do not provide as
662 ** much information about problems as programmers might like. In an effort to
663 ** address this, newer versions of SQLite (version 3.3.8 and later) include
664 ** support for additional result codes that provide more detailed information
665 ** about errors. These [extended result codes] are enabled or disabled
666 ** on a per database connection basis using the
667 ** [sqlite3_extended_result_codes()] API. Or, the extended code for
668 ** the most recent error can be obtained using
669 ** [sqlite3_extended_errcode()].
671 #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
672 #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
673 #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
674 #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
675 #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
676 #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
677 #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
678 #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
679 #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
680 #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
681 #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
682 #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
683 #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
684 #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
685 #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
686 #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
687 #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
688 #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))
689 #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))
690 #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))
691 #define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8))
692 #define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8))
693 #define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8))
694 #define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8))
695 #define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8))
696 #define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8))
697 #define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8))
698 #define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8))
699 #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))
700 #define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))
701 #define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8))
702 #define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))
703 #define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8))
704 #define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8))
705 #define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8))
706 #define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8))
707 #define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8))
708 #define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8))
709 #define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8))
710 #define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8))
711 #define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8))
712 #define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8))
713 #define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8))
714 #define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8))
715 #define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8))
716 #define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8))
717 #define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8))
718 #define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8))
719 #define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8))
720 #define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8))
721 #define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8))
722 #define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8))
723 #define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
724 #define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8))
725 #define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8))
728 ** CAPI3REF: Flags For File Open Operations
730 ** These bit values are intended for use in the
731 ** 3rd parameter to the [sqlite3_open_v2()] interface and
732 ** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
734 #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
735 #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
736 #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
737 #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
738 #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
739 #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
740 #define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */
741 #define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */
742 #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
743 #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
744 #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
745 #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
746 #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
747 #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
748 #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
749 #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
750 #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
751 #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
752 #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
753 #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */
755 /* Reserved: 0x00F00000 */
758 ** CAPI3REF: Device Characteristics
760 ** The xDeviceCharacteristics method of the [sqlite3_io_methods]
761 ** object returns an integer which is a vector of these
762 ** bit values expressing I/O characteristics of the mass storage
763 ** device that holds the file that the [sqlite3_io_methods]
766 ** The SQLITE_IOCAP_ATOMIC property means that all writes of
767 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
768 ** mean that writes of blocks that are nnn bytes in size and
769 ** are aligned to an address which is an integer multiple of
770 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
771 ** that when data is appended to a file, the data is appended
772 ** first then the size of the file is extended, never the other
773 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
774 ** information is written to disk in the same order as calls
775 ** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
776 ** after reboot following a crash or power loss, the only bytes in a
777 ** file that were written at the application level might have changed
778 ** and that adjacent bytes, even bytes within the same sector are
779 ** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
780 ** flag indicate that a file cannot be deleted when open. The
781 ** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
782 ** read-only media and cannot be changed even by processes with
783 ** elevated privileges.
785 #define SQLITE_IOCAP_ATOMIC 0x00000001
786 #define SQLITE_IOCAP_ATOMIC512 0x00000002
787 #define SQLITE_IOCAP_ATOMIC1K 0x00000004
788 #define SQLITE_IOCAP_ATOMIC2K 0x00000008
789 #define SQLITE_IOCAP_ATOMIC4K 0x00000010
790 #define SQLITE_IOCAP_ATOMIC8K 0x00000020
791 #define SQLITE_IOCAP_ATOMIC16K 0x00000040
792 #define SQLITE_IOCAP_ATOMIC32K 0x00000080
793 #define SQLITE_IOCAP_ATOMIC64K 0x00000100
794 #define SQLITE_IOCAP_SAFE_APPEND 0x00000200
795 #define SQLITE_IOCAP_SEQUENTIAL 0x00000400
796 #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800
797 #define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000
798 #define SQLITE_IOCAP_IMMUTABLE 0x00002000
801 ** CAPI3REF: File Locking Levels
803 ** SQLite uses one of these integer values as the second
804 ** argument to calls it makes to the xLock() and xUnlock() methods
805 ** of an [sqlite3_io_methods] object.
807 #define SQLITE_LOCK_NONE 0
808 #define SQLITE_LOCK_SHARED 1
809 #define SQLITE_LOCK_RESERVED 2
810 #define SQLITE_LOCK_PENDING 3
811 #define SQLITE_LOCK_EXCLUSIVE 4
814 ** CAPI3REF: Synchronization Type Flags
816 ** When SQLite invokes the xSync() method of an
817 ** [sqlite3_io_methods] object it uses a combination of
818 ** these integer values as the second argument.
820 ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
821 ** sync operation only needs to flush data to mass storage. Inode
822 ** information need not be flushed. If the lower four bits of the flag
823 ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
824 ** If the lower four bits equal SQLITE_SYNC_FULL, that means
825 ** to use Mac OS X style fullsync instead of fsync().
827 ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
828 ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
829 ** settings. The [synchronous pragma] determines when calls to the
830 ** xSync VFS method occur and applies uniformly across all platforms.
831 ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
832 ** energetic or rigorous or forceful the sync operations are and
833 ** only make a difference on Mac OSX for the default SQLite code.
834 ** (Third-party VFS implementations might also make the distinction
835 ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
836 ** operating systems natively supported by SQLite, only Mac OSX
837 ** cares about the difference.)
839 #define SQLITE_SYNC_NORMAL 0x00002
840 #define SQLITE_SYNC_FULL 0x00003
841 #define SQLITE_SYNC_DATAONLY 0x00010
844 ** CAPI3REF: OS Interface Open File Handle
846 ** An [sqlite3_file] object represents an open file in the
847 ** [sqlite3_vfs | OS interface layer]. Individual OS interface
848 ** implementations will
849 ** want to subclass this object by appending additional fields
850 ** for their own use. The pMethods entry is a pointer to an
851 ** [sqlite3_io_methods] object that defines methods for performing
852 ** I/O operations on the open file.
854 typedef struct sqlite3_file sqlite3_file;
855 struct sqlite3_file {
856 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
860 ** CAPI3REF: OS Interface File Virtual Methods Object
862 ** Every file opened by the [sqlite3_vfs.xOpen] method populates an
863 ** [sqlite3_file] object (or, more commonly, a subclass of the
864 ** [sqlite3_file] object) with a pointer to an instance of this object.
865 ** This object defines the methods used to perform various operations
866 ** against the open file represented by the [sqlite3_file] object.
868 ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
869 ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
870 ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The
871 ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
872 ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
875 ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
876 ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
877 ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
878 ** flag may be ORed in to indicate that only the data of the file
879 ** and not its inode needs to be synced.
881 ** The integer values to xLock() and xUnlock() are one of
883 ** <li> [SQLITE_LOCK_NONE],
884 ** <li> [SQLITE_LOCK_SHARED],
885 ** <li> [SQLITE_LOCK_RESERVED],
886 ** <li> [SQLITE_LOCK_PENDING], or
887 ** <li> [SQLITE_LOCK_EXCLUSIVE].
889 ** xLock() increases the lock. xUnlock() decreases the lock.
890 ** The xCheckReservedLock() method checks whether any database connection,
891 ** either in this process or in some other process, is holding a RESERVED,
892 ** PENDING, or EXCLUSIVE lock on the file. It returns true
893 ** if such a lock exists and false otherwise.
895 ** The xFileControl() method is a generic interface that allows custom
896 ** VFS implementations to directly control an open file using the
897 ** [sqlite3_file_control()] interface. The second "op" argument is an
898 ** integer opcode. The third argument is a generic pointer intended to
899 ** point to a structure that may contain arguments or space in which to
900 ** write return values. Potential uses for xFileControl() might be
901 ** functions to enable blocking locks with timeouts, to change the
902 ** locking strategy (for example to use dot-file locks), to inquire
903 ** about the status of a lock, or to break stale locks. The SQLite
904 ** core reserves all opcodes less than 100 for its own use.
905 ** A [file control opcodes | list of opcodes] less than 100 is available.
906 ** Applications that define a custom xFileControl method should use opcodes
907 ** greater than 100 to avoid conflicts. VFS implementations should
908 ** return [SQLITE_NOTFOUND] for file control opcodes that they do not
911 ** The xSectorSize() method returns the sector size of the
912 ** device that underlies the file. The sector size is the
913 ** minimum write that can be performed without disturbing
914 ** other bytes in the file. The xDeviceCharacteristics()
915 ** method returns a bit vector describing behaviors of the
916 ** underlying device:
919 ** <li> [SQLITE_IOCAP_ATOMIC]
920 ** <li> [SQLITE_IOCAP_ATOMIC512]
921 ** <li> [SQLITE_IOCAP_ATOMIC1K]
922 ** <li> [SQLITE_IOCAP_ATOMIC2K]
923 ** <li> [SQLITE_IOCAP_ATOMIC4K]
924 ** <li> [SQLITE_IOCAP_ATOMIC8K]
925 ** <li> [SQLITE_IOCAP_ATOMIC16K]
926 ** <li> [SQLITE_IOCAP_ATOMIC32K]
927 ** <li> [SQLITE_IOCAP_ATOMIC64K]
928 ** <li> [SQLITE_IOCAP_SAFE_APPEND]
929 ** <li> [SQLITE_IOCAP_SEQUENTIAL]
932 ** The SQLITE_IOCAP_ATOMIC property means that all writes of
933 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
934 ** mean that writes of blocks that are nnn bytes in size and
935 ** are aligned to an address which is an integer multiple of
936 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
937 ** that when data is appended to a file, the data is appended
938 ** first then the size of the file is extended, never the other
939 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
940 ** information is written to disk in the same order as calls
943 ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
944 ** in the unread portions of the buffer with zeros. A VFS that
945 ** fails to zero-fill short reads might seem to work. However,
946 ** failure to zero-fill short reads will eventually lead to
947 ** database corruption.
949 typedef struct sqlite3_io_methods sqlite3_io_methods;
950 struct sqlite3_io_methods {
952 int (*xClose)(sqlite3_file*);
953 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
954 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
955 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
956 int (*xSync)(sqlite3_file*, int flags);
957 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
958 int (*xLock)(sqlite3_file*, int);
959 int (*xUnlock)(sqlite3_file*, int);
960 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
961 int (*xFileControl)(sqlite3_file*, int op, void *pArg);
962 int (*xSectorSize)(sqlite3_file*);
963 int (*xDeviceCharacteristics)(sqlite3_file*);
964 /* Methods above are valid for version 1 */
965 int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
966 int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
967 void (*xShmBarrier)(sqlite3_file*);
968 int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
969 /* Methods above are valid for version 2 */
970 int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
971 int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
972 /* Methods above are valid for version 3 */
973 /* Additional methods may be added in future releases */
977 ** CAPI3REF: Standard File Control Opcodes
978 ** KEYWORDS: {file control opcodes} {file control opcode}
980 ** These integer constants are opcodes for the xFileControl method
981 ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
985 ** <li>[[SQLITE_FCNTL_LOCKSTATE]]
986 ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
987 ** opcode causes the xFileControl method to write the current state of
988 ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
989 ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
990 ** into an integer that the pArg argument points to. This capability
991 ** is used during testing and is only available when the SQLITE_TEST
992 ** compile-time option is used.
994 ** <li>[[SQLITE_FCNTL_SIZE_HINT]]
995 ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
996 ** layer a hint of how large the database file will grow to be during the
997 ** current transaction. This hint is not guaranteed to be accurate but it
998 ** is often close. The underlying VFS might choose to preallocate database
999 ** file space based on this hint in order to help writes to the database
1002 ** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
1003 ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
1004 ** extends and truncates the database file in chunks of a size specified
1005 ** by the user. The fourth argument to [sqlite3_file_control()] should
1006 ** point to an integer (type int) containing the new chunk-size to use
1007 ** for the nominated database. Allocating database file space in large
1008 ** chunks (say 1MB at a time), may reduce file-system fragmentation and
1009 ** improve performance on some systems.
1011 ** <li>[[SQLITE_FCNTL_FILE_POINTER]]
1012 ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
1013 ** to the [sqlite3_file] object associated with a particular database
1014 ** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER].
1016 ** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]]
1017 ** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer
1018 ** to the [sqlite3_file] object associated with the journal file (either
1019 ** the [rollback journal] or the [write-ahead log]) for a particular database
1020 ** connection. See also [SQLITE_FCNTL_FILE_POINTER].
1022 ** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
1023 ** No longer in use.
1025 ** <li>[[SQLITE_FCNTL_SYNC]]
1026 ** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
1027 ** sent to the VFS immediately before the xSync method is invoked on a
1028 ** database file descriptor. Or, if the xSync method is not invoked
1029 ** because the user has configured SQLite with
1030 ** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
1031 ** of the xSync method. In most cases, the pointer argument passed with
1032 ** this file-control is NULL. However, if the database file is being synced
1033 ** as part of a multi-database commit, the argument points to a nul-terminated
1034 ** string containing the transactions master-journal file name. VFSes that
1035 ** do not need this signal should silently ignore this opcode. Applications
1036 ** should not call [sqlite3_file_control()] with this opcode as doing so may
1037 ** disrupt the operation of the specialized VFSes that do require it.
1039 ** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
1040 ** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
1041 ** and sent to the VFS after a transaction has been committed immediately
1042 ** but before the database is unlocked. VFSes that do not need this signal
1043 ** should silently ignore this opcode. Applications should not call
1044 ** [sqlite3_file_control()] with this opcode as doing so may disrupt the
1045 ** operation of the specialized VFSes that do require it.
1047 ** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
1048 ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
1049 ** retry counts and intervals for certain disk I/O operations for the
1050 ** windows [VFS] in order to provide robustness in the presence of
1051 ** anti-virus programs. By default, the windows VFS will retry file read,
1052 ** file write, and file delete operations up to 10 times, with a delay
1053 ** of 25 milliseconds before the first retry and with the delay increasing
1054 ** by an additional 25 milliseconds with each subsequent retry. This
1055 ** opcode allows these two values (10 retries and 25 milliseconds of delay)
1056 ** to be adjusted. The values are changed for all database connections
1057 ** within the same process. The argument is a pointer to an array of two
1058 ** integers where the first integer i the new retry count and the second
1059 ** integer is the delay. If either integer is negative, then the setting
1060 ** is not changed but instead the prior value of that setting is written
1061 ** into the array entry, allowing the current retry settings to be
1062 ** interrogated. The zDbName parameter is ignored.
1064 ** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
1065 ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
1066 ** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary
1067 ** write ahead log and shared memory files used for transaction control
1068 ** are automatically deleted when the latest connection to the database
1069 ** closes. Setting persistent WAL mode causes those files to persist after
1070 ** close. Persisting the files is useful when other processes that do not
1071 ** have write permission on the directory containing the database file want
1072 ** to read the database file, as the WAL and shared memory files must exist
1073 ** in order for the database to be readable. The fourth parameter to
1074 ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
1075 ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
1076 ** WAL mode. If the integer is -1, then it is overwritten with the current
1077 ** WAL persistence setting.
1079 ** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
1080 ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
1081 ** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting
1082 ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
1083 ** xDeviceCharacteristics methods. The fourth parameter to
1084 ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
1085 ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
1086 ** mode. If the integer is -1, then it is overwritten with the current
1087 ** zero-damage mode setting.
1089 ** <li>[[SQLITE_FCNTL_OVERWRITE]]
1090 ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
1091 ** a write transaction to indicate that, unless it is rolled back for some
1092 ** reason, the entire database file will be overwritten by the current
1093 ** transaction. This is used by VACUUM operations.
1095 ** <li>[[SQLITE_FCNTL_VFSNAME]]
1096 ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
1097 ** all [VFSes] in the VFS stack. The names are of all VFS shims and the
1098 ** final bottom-level VFS are written into memory obtained from
1099 ** [sqlite3_malloc()] and the result is stored in the char* variable
1100 ** that the fourth parameter of [sqlite3_file_control()] points to.
1101 ** The caller is responsible for freeing the memory when done. As with
1102 ** all file-control actions, there is no guarantee that this will actually
1103 ** do anything. Callers should initialize the char* variable to a NULL
1104 ** pointer in case this file-control is not implemented. This file-control
1105 ** is intended for diagnostic use only.
1107 ** <li>[[SQLITE_FCNTL_VFS_POINTER]]
1108 ** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
1109 ** [VFSes] currently in use. ^(The argument X in
1110 ** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
1111 ** of type "[sqlite3_vfs] **". This opcodes will set *X
1112 ** to a pointer to the top-level VFS.)^
1113 ** ^When there are multiple VFS shims in the stack, this opcode finds the
1114 ** upper-most shim only.
1116 ** <li>[[SQLITE_FCNTL_PRAGMA]]
1117 ** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
1118 ** file control is sent to the open [sqlite3_file] object corresponding
1119 ** to the database file to which the pragma statement refers. ^The argument
1120 ** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
1121 ** pointers to strings (char**) in which the second element of the array
1122 ** is the name of the pragma and the third element is the argument to the
1123 ** pragma or NULL if the pragma has no argument. ^The handler for an
1124 ** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
1125 ** of the char** argument point to a string obtained from [sqlite3_mprintf()]
1126 ** or the equivalent and that string will become the result of the pragma or
1127 ** the error message if the pragma fails. ^If the
1128 ** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
1129 ** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA]
1130 ** file control returns [SQLITE_OK], then the parser assumes that the
1131 ** VFS has handled the PRAGMA itself and the parser generates a no-op
1132 ** prepared statement if result string is NULL, or that returns a copy
1133 ** of the result string if the string is non-NULL.
1134 ** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
1135 ** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
1136 ** that the VFS encountered an error while handling the [PRAGMA] and the
1137 ** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA]
1138 ** file control occurs at the beginning of pragma statement analysis and so
1139 ** it is able to override built-in [PRAGMA] statements.
1141 ** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
1142 ** ^The [SQLITE_FCNTL_BUSYHANDLER]
1143 ** file-control may be invoked by SQLite on the database file handle
1144 ** shortly after it is opened in order to provide a custom VFS with access
1145 ** to the connections busy-handler callback. The argument is of type (void **)
1146 ** - an array of two (void *) values. The first (void *) actually points
1147 ** to a function of type (int (*)(void *)). In order to invoke the connections
1148 ** busy-handler, this function should be invoked with the second (void *) in
1149 ** the array as the only argument. If it returns non-zero, then the operation
1150 ** should be retried. If it returns zero, the custom VFS should abandon the
1151 ** current operation.
1153 ** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
1154 ** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
1155 ** to have SQLite generate a
1156 ** temporary filename using the same algorithm that is followed to generate
1157 ** temporary filenames for TEMP tables and other internal uses. The
1158 ** argument should be a char** which will be filled with the filename
1159 ** written into memory obtained from [sqlite3_malloc()]. The caller should
1160 ** invoke [sqlite3_free()] on the result to avoid a memory leak.
1162 ** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
1163 ** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
1164 ** maximum number of bytes that will be used for memory-mapped I/O.
1165 ** The argument is a pointer to a value of type sqlite3_int64 that
1166 ** is an advisory maximum number of bytes in the file to memory map. The
1167 ** pointer is overwritten with the old value. The limit is not changed if
1168 ** the value originally pointed to is negative, and so the current limit
1169 ** can be queried by passing in a pointer to a negative number. This
1170 ** file-control is used internally to implement [PRAGMA mmap_size].
1172 ** <li>[[SQLITE_FCNTL_TRACE]]
1173 ** The [SQLITE_FCNTL_TRACE] file control provides advisory information
1174 ** to the VFS about what the higher layers of the SQLite stack are doing.
1175 ** This file control is used by some VFS activity tracing [shims].
1176 ** The argument is a zero-terminated string. Higher layers in the
1177 ** SQLite stack may generate instances of this file control if
1178 ** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
1180 ** <li>[[SQLITE_FCNTL_HAS_MOVED]]
1181 ** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
1182 ** pointer to an integer and it writes a boolean into that integer depending
1183 ** on whether or not the file has been renamed, moved, or deleted since it
1184 ** was first opened.
1186 ** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
1187 ** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This
1188 ** opcode causes the xFileControl method to swap the file handle with the one
1189 ** pointed to by the pArg argument. This capability is used during testing
1190 ** and only needs to be supported when SQLITE_TEST is defined.
1192 ** <li>[[SQLITE_FCNTL_WAL_BLOCK]]
1193 ** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
1194 ** be advantageous to block on the next WAL lock if the lock is not immediately
1195 ** available. The WAL subsystem issues this signal during rare
1196 ** circumstances in order to fix a problem with priority inversion.
1197 ** Applications should <em>not</em> use this file-control.
1199 ** <li>[[SQLITE_FCNTL_ZIPVFS]]
1200 ** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other
1201 ** VFS should return SQLITE_NOTFOUND for this opcode.
1203 ** <li>[[SQLITE_FCNTL_RBU]]
1204 ** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by
1205 ** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for
1209 #define SQLITE_FCNTL_LOCKSTATE 1
1210 #define SQLITE_FCNTL_GET_LOCKPROXYFILE 2
1211 #define SQLITE_FCNTL_SET_LOCKPROXYFILE 3
1212 #define SQLITE_FCNTL_LAST_ERRNO 4
1213 #define SQLITE_FCNTL_SIZE_HINT 5
1214 #define SQLITE_FCNTL_CHUNK_SIZE 6
1215 #define SQLITE_FCNTL_FILE_POINTER 7
1216 #define SQLITE_FCNTL_SYNC_OMITTED 8
1217 #define SQLITE_FCNTL_WIN32_AV_RETRY 9
1218 #define SQLITE_FCNTL_PERSIST_WAL 10
1219 #define SQLITE_FCNTL_OVERWRITE 11
1220 #define SQLITE_FCNTL_VFSNAME 12
1221 #define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13
1222 #define SQLITE_FCNTL_PRAGMA 14
1223 #define SQLITE_FCNTL_BUSYHANDLER 15
1224 #define SQLITE_FCNTL_TEMPFILENAME 16
1225 #define SQLITE_FCNTL_MMAP_SIZE 18
1226 #define SQLITE_FCNTL_TRACE 19
1227 #define SQLITE_FCNTL_HAS_MOVED 20
1228 #define SQLITE_FCNTL_SYNC 21
1229 #define SQLITE_FCNTL_COMMIT_PHASETWO 22
1230 #define SQLITE_FCNTL_WIN32_SET_HANDLE 23
1231 #define SQLITE_FCNTL_WAL_BLOCK 24
1232 #define SQLITE_FCNTL_ZIPVFS 25
1233 #define SQLITE_FCNTL_RBU 26
1234 #define SQLITE_FCNTL_VFS_POINTER 27
1235 #define SQLITE_FCNTL_JOURNAL_POINTER 28
1237 /* deprecated names */
1238 #define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE
1239 #define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE
1240 #define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO
1244 ** CAPI3REF: Mutex Handle
1246 ** The mutex module within SQLite defines [sqlite3_mutex] to be an
1247 ** abstract type for a mutex object. The SQLite core never looks
1248 ** at the internal representation of an [sqlite3_mutex]. It only
1249 ** deals with pointers to the [sqlite3_mutex] object.
1251 ** Mutexes are created using [sqlite3_mutex_alloc()].
1253 typedef struct sqlite3_mutex sqlite3_mutex;
1256 ** CAPI3REF: OS Interface Object
1258 ** An instance of the sqlite3_vfs object defines the interface between
1259 ** the SQLite core and the underlying operating system. The "vfs"
1260 ** in the name of the object stands for "virtual file system". See
1261 ** the [VFS | VFS documentation] for further information.
1263 ** The value of the iVersion field is initially 1 but may be larger in
1264 ** future versions of SQLite. Additional fields may be appended to this
1265 ** object when the iVersion value is increased. Note that the structure
1266 ** of the sqlite3_vfs object changes in the transaction between
1267 ** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
1270 ** The szOsFile field is the size of the subclassed [sqlite3_file]
1271 ** structure used by this VFS. mxPathname is the maximum length of
1272 ** a pathname in this VFS.
1274 ** Registered sqlite3_vfs objects are kept on a linked list formed by
1275 ** the pNext pointer. The [sqlite3_vfs_register()]
1276 ** and [sqlite3_vfs_unregister()] interfaces manage this list
1277 ** in a thread-safe way. The [sqlite3_vfs_find()] interface
1278 ** searches the list. Neither the application code nor the VFS
1279 ** implementation should use the pNext pointer.
1281 ** The pNext field is the only field in the sqlite3_vfs
1282 ** structure that SQLite will ever modify. SQLite will only access
1283 ** or modify this field while holding a particular static mutex.
1284 ** The application should never modify anything within the sqlite3_vfs
1285 ** object once the object has been registered.
1287 ** The zName field holds the name of the VFS module. The name must
1288 ** be unique across all VFS modules.
1290 ** [[sqlite3_vfs.xOpen]]
1291 ** ^SQLite guarantees that the zFilename parameter to xOpen
1292 ** is either a NULL pointer or string obtained
1293 ** from xFullPathname() with an optional suffix added.
1294 ** ^If a suffix is added to the zFilename parameter, it will
1295 ** consist of a single "-" character followed by no more than
1296 ** 11 alphanumeric and/or "-" characters.
1297 ** ^SQLite further guarantees that
1298 ** the string will be valid and unchanged until xClose() is
1299 ** called. Because of the previous sentence,
1300 ** the [sqlite3_file] can safely store a pointer to the
1301 ** filename if it needs to remember the filename for some reason.
1302 ** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1303 ** must invent its own temporary name for the file. ^Whenever the
1304 ** xFilename parameter is NULL it will also be the case that the
1305 ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
1307 ** The flags argument to xOpen() includes all bits set in
1308 ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
1309 ** or [sqlite3_open16()] is used, then flags includes at least
1310 ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
1311 ** If xOpen() opens a file read-only then it sets *pOutFlags to
1312 ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
1314 ** ^(SQLite will also add one of the following flags to the xOpen()
1315 ** call, depending on the object being opened:
1318 ** <li> [SQLITE_OPEN_MAIN_DB]
1319 ** <li> [SQLITE_OPEN_MAIN_JOURNAL]
1320 ** <li> [SQLITE_OPEN_TEMP_DB]
1321 ** <li> [SQLITE_OPEN_TEMP_JOURNAL]
1322 ** <li> [SQLITE_OPEN_TRANSIENT_DB]
1323 ** <li> [SQLITE_OPEN_SUBJOURNAL]
1324 ** <li> [SQLITE_OPEN_MASTER_JOURNAL]
1325 ** <li> [SQLITE_OPEN_WAL]
1328 ** The file I/O implementation can use the object type flags to
1329 ** change the way it deals with files. For example, an application
1330 ** that does not care about crash recovery or rollback might make
1331 ** the open of a journal file a no-op. Writes to this journal would
1332 ** also be no-ops, and any attempt to read the journal would return
1333 ** SQLITE_IOERR. Or the implementation might recognize that a database
1334 ** file will be doing page-aligned sector reads and writes in a random
1335 ** order and set up its I/O subsystem accordingly.
1337 ** SQLite might also add one of the following flags to the xOpen method:
1340 ** <li> [SQLITE_OPEN_DELETEONCLOSE]
1341 ** <li> [SQLITE_OPEN_EXCLUSIVE]
1344 ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1345 ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE]
1346 ** will be set for TEMP databases and their journals, transient
1347 ** databases, and subjournals.
1349 ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1350 ** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1351 ** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1352 ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
1353 ** SQLITE_OPEN_CREATE, is used to indicate that file should always
1354 ** be created, and that it is an error if it already exists.
1355 ** It is <i>not</i> used to indicate the file should be opened
1356 ** for exclusive access.
1358 ** ^At least szOsFile bytes of memory are allocated by SQLite
1359 ** to hold the [sqlite3_file] structure passed as the third
1360 ** argument to xOpen. The xOpen method does not have to
1361 ** allocate the structure; it should just fill it in. Note that
1362 ** the xOpen method must set the sqlite3_file.pMethods to either
1363 ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
1364 ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
1365 ** element will be valid after xOpen returns regardless of the success
1366 ** or failure of the xOpen call.
1368 ** [[sqlite3_vfs.xAccess]]
1369 ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1370 ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1371 ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1372 ** to test whether a file is at least readable. The file can be a
1375 ** ^SQLite will always allocate at least mxPathname+1 bytes for the
1376 ** output buffer xFullPathname. The exact size of the output buffer
1377 ** is also passed as a parameter to both methods. If the output buffer
1378 ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1379 ** handled as a fatal error by SQLite, vfs implementations should endeavor
1380 ** to prevent this by setting mxPathname to a sufficiently large value.
1382 ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1383 ** interfaces are not strictly a part of the filesystem, but they are
1384 ** included in the VFS structure for completeness.
1385 ** The xRandomness() function attempts to return nBytes bytes
1386 ** of good-quality randomness into zOut. The return value is
1387 ** the actual number of bytes of randomness obtained.
1388 ** The xSleep() method causes the calling thread to sleep for at
1389 ** least the number of microseconds given. ^The xCurrentTime()
1390 ** method returns a Julian Day Number for the current date and time as
1391 ** a floating point value.
1392 ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1393 ** Day Number multiplied by 86400000 (the number of milliseconds in
1395 ** ^SQLite will use the xCurrentTimeInt64() method to get the current
1396 ** date and time if that method is available (if iVersion is 2 or
1397 ** greater and the function pointer is not NULL) and will fall back
1398 ** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
1400 ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
1401 ** are not used by the SQLite core. These optional interfaces are provided
1402 ** by some VFSes to facilitate testing of the VFS code. By overriding
1403 ** system calls with functions under its control, a test program can
1404 ** simulate faults and error conditions that would otherwise be difficult
1405 ** or impossible to induce. The set of system calls that can be overridden
1406 ** varies from one VFS to another, and from one version of the same VFS to the
1407 ** next. Applications that use these interfaces must be prepared for any
1408 ** or all of these interfaces to be NULL or for their behavior to change
1409 ** from one release to the next. Applications must not attempt to access
1410 ** any of these methods if the iVersion of the VFS is less than 3.
1412 typedef struct sqlite3_vfs sqlite3_vfs;
1413 typedef void (*sqlite3_syscall_ptr)(void);
1414 struct sqlite3_vfs {
1415 int iVersion; /* Structure version number (currently 3) */
1416 int szOsFile; /* Size of subclassed sqlite3_file */
1417 int mxPathname; /* Maximum file pathname length */
1418 sqlite3_vfs *pNext; /* Next registered VFS */
1419 const char *zName; /* Name of this virtual file system */
1420 void *pAppData; /* Pointer to application-specific data */
1421 int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
1422 int flags, int *pOutFlags);
1423 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
1424 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
1425 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
1426 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
1427 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
1428 void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
1429 void (*xDlClose)(sqlite3_vfs*, void*);
1430 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
1431 int (*xSleep)(sqlite3_vfs*, int microseconds);
1432 int (*xCurrentTime)(sqlite3_vfs*, double*);
1433 int (*xGetLastError)(sqlite3_vfs*, int, char *);
1435 ** The methods above are in version 1 of the sqlite_vfs object
1436 ** definition. Those that follow are added in version 2 or later
1438 int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
1440 ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
1441 ** Those below are for version 3 and greater.
1443 int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
1444 sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
1445 const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
1447 ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1448 ** New fields may be appended in figure versions. The iVersion
1449 ** value will increment whenever this happens.
1454 ** CAPI3REF: Flags for the xAccess VFS method
1456 ** These integer constants can be used as the third parameter to
1457 ** the xAccess method of an [sqlite3_vfs] object. They determine
1458 ** what kind of permissions the xAccess method is looking for.
1459 ** With SQLITE_ACCESS_EXISTS, the xAccess method
1460 ** simply checks whether the file exists.
1461 ** With SQLITE_ACCESS_READWRITE, the xAccess method
1462 ** checks whether the named directory is both readable and writable
1463 ** (in other words, if files can be added, removed, and renamed within
1465 ** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1466 ** [temp_store_directory pragma], though this could change in a future
1467 ** release of SQLite.
1468 ** With SQLITE_ACCESS_READ, the xAccess method
1469 ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is
1470 ** currently unused, though it might be used in a future release of
1473 #define SQLITE_ACCESS_EXISTS 0
1474 #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */
1475 #define SQLITE_ACCESS_READ 2 /* Unused */
1478 ** CAPI3REF: Flags for the xShmLock VFS method
1480 ** These integer constants define the various locking operations
1481 ** allowed by the xShmLock method of [sqlite3_io_methods]. The
1482 ** following are the only legal combinations of flags to the
1486 ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
1487 ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
1488 ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
1489 ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
1492 ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1493 ** was given on the corresponding lock.
1495 ** The xShmLock method can transition between unlocked and SHARED or
1496 ** between unlocked and EXCLUSIVE. It cannot transition between SHARED
1499 #define SQLITE_SHM_UNLOCK 1
1500 #define SQLITE_SHM_LOCK 2
1501 #define SQLITE_SHM_SHARED 4
1502 #define SQLITE_SHM_EXCLUSIVE 8
1505 ** CAPI3REF: Maximum xShmLock index
1507 ** The xShmLock method on [sqlite3_io_methods] may use values
1508 ** between 0 and this upper bound as its "offset" argument.
1509 ** The SQLite core will never attempt to acquire or release a
1510 ** lock outside of this range
1512 #define SQLITE_SHM_NLOCK 8
1516 ** CAPI3REF: Initialize The SQLite Library
1518 ** ^The sqlite3_initialize() routine initializes the
1519 ** SQLite library. ^The sqlite3_shutdown() routine
1520 ** deallocates any resources that were allocated by sqlite3_initialize().
1521 ** These routines are designed to aid in process initialization and
1522 ** shutdown on embedded systems. Workstation applications using
1523 ** SQLite normally do not need to invoke either of these routines.
1525 ** A call to sqlite3_initialize() is an "effective" call if it is
1526 ** the first time sqlite3_initialize() is invoked during the lifetime of
1527 ** the process, or if it is the first time sqlite3_initialize() is invoked
1528 ** following a call to sqlite3_shutdown(). ^(Only an effective call
1529 ** of sqlite3_initialize() does any initialization. All other calls
1530 ** are harmless no-ops.)^
1532 ** A call to sqlite3_shutdown() is an "effective" call if it is the first
1533 ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
1534 ** an effective call to sqlite3_shutdown() does any deinitialization.
1535 ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1537 ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1538 ** is not. The sqlite3_shutdown() interface must only be called from a
1539 ** single thread. All open [database connections] must be closed and all
1540 ** other SQLite resources must be deallocated prior to invoking
1541 ** sqlite3_shutdown().
1543 ** Among other things, ^sqlite3_initialize() will invoke
1544 ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
1545 ** will invoke sqlite3_os_end().
1547 ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1548 ** ^If for some reason, sqlite3_initialize() is unable to initialize
1549 ** the library (perhaps it is unable to allocate a needed resource such
1550 ** as a mutex) it returns an [error code] other than [SQLITE_OK].
1552 ** ^The sqlite3_initialize() routine is called internally by many other
1553 ** SQLite interfaces so that an application usually does not need to
1554 ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
1555 ** calls sqlite3_initialize() so the SQLite library will be automatically
1556 ** initialized when [sqlite3_open()] is called if it has not be initialized
1557 ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1558 ** compile-time option, then the automatic calls to sqlite3_initialize()
1559 ** are omitted and the application must call sqlite3_initialize() directly
1560 ** prior to using any other SQLite interface. For maximum portability,
1561 ** it is recommended that applications always invoke sqlite3_initialize()
1562 ** directly prior to using any other SQLite interface. Future releases
1563 ** of SQLite may require this. In other words, the behavior exhibited
1564 ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1565 ** default behavior in some future release of SQLite.
1567 ** The sqlite3_os_init() routine does operating-system specific
1568 ** initialization of the SQLite library. The sqlite3_os_end()
1569 ** routine undoes the effect of sqlite3_os_init(). Typical tasks
1570 ** performed by these routines include allocation or deallocation
1571 ** of static resources, initialization of global variables,
1572 ** setting up a default [sqlite3_vfs] module, or setting up
1573 ** a default configuration using [sqlite3_config()].
1575 ** The application should never invoke either sqlite3_os_init()
1576 ** or sqlite3_os_end() directly. The application should only invoke
1577 ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
1578 ** interface is called automatically by sqlite3_initialize() and
1579 ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
1580 ** implementations for sqlite3_os_init() and sqlite3_os_end()
1581 ** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1582 ** When [custom builds | built for other platforms]
1583 ** (using the [SQLITE_OS_OTHER=1] compile-time
1584 ** option) the application must supply a suitable implementation for
1585 ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
1586 ** implementation of sqlite3_os_init() or sqlite3_os_end()
1587 ** must return [SQLITE_OK] on success and some other [error code] upon
1590 SQLITE_API int SQLITE_STDCALL sqlite3_initialize(void);
1591 SQLITE_API int SQLITE_STDCALL sqlite3_shutdown(void);
1592 SQLITE_API int SQLITE_STDCALL sqlite3_os_init(void);
1593 SQLITE_API int SQLITE_STDCALL sqlite3_os_end(void);
1596 ** CAPI3REF: Configuring The SQLite Library
1598 ** The sqlite3_config() interface is used to make global configuration
1599 ** changes to SQLite in order to tune SQLite to the specific needs of
1600 ** the application. The default configuration is recommended for most
1601 ** applications and so this routine is usually not necessary. It is
1602 ** provided to support rare applications with unusual needs.
1604 ** <b>The sqlite3_config() interface is not threadsafe. The application
1605 ** must ensure that no other SQLite interfaces are invoked by other
1606 ** threads while sqlite3_config() is running.</b>
1608 ** The sqlite3_config() interface
1609 ** may only be invoked prior to library initialization using
1610 ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1611 ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1612 ** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
1613 ** Note, however, that ^sqlite3_config() can be called as part of the
1614 ** implementation of an application-defined [sqlite3_os_init()].
1616 ** The first argument to sqlite3_config() is an integer
1617 ** [configuration option] that determines
1618 ** what property of SQLite is to be configured. Subsequent arguments
1619 ** vary depending on the [configuration option]
1620 ** in the first argument.
1622 ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1623 ** ^If the option is unknown or SQLite is unable to set the option
1624 ** then this routine returns a non-zero [error code].
1626 SQLITE_API int SQLITE_CDECL sqlite3_config(int, ...);
1629 ** CAPI3REF: Configure database connections
1632 ** The sqlite3_db_config() interface is used to make configuration
1633 ** changes to a [database connection]. The interface is similar to
1634 ** [sqlite3_config()] except that the changes apply to a single
1635 ** [database connection] (specified in the first argument).
1637 ** The second argument to sqlite3_db_config(D,V,...) is the
1638 ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
1639 ** that indicates what aspect of the [database connection] is being configured.
1640 ** Subsequent arguments vary depending on the configuration verb.
1642 ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1643 ** the call is considered successful.
1645 SQLITE_API int SQLITE_CDECL sqlite3_db_config(sqlite3*, int op, ...);
1648 ** CAPI3REF: Memory Allocation Routines
1650 ** An instance of this object defines the interface between SQLite
1651 ** and low-level memory allocation routines.
1653 ** This object is used in only one place in the SQLite interface.
1654 ** A pointer to an instance of this object is the argument to
1655 ** [sqlite3_config()] when the configuration option is
1656 ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1657 ** By creating an instance of this object
1658 ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1659 ** during configuration, an application can specify an alternative
1660 ** memory allocation subsystem for SQLite to use for all of its
1661 ** dynamic memory needs.
1663 ** Note that SQLite comes with several [built-in memory allocators]
1664 ** that are perfectly adequate for the overwhelming majority of applications
1665 ** and that this object is only useful to a tiny minority of applications
1666 ** with specialized memory allocation requirements. This object is
1667 ** also used during testing of SQLite in order to specify an alternative
1668 ** memory allocator that simulates memory out-of-memory conditions in
1669 ** order to verify that SQLite recovers gracefully from such
1672 ** The xMalloc, xRealloc, and xFree methods must work like the
1673 ** malloc(), realloc() and free() functions from the standard C library.
1674 ** ^SQLite guarantees that the second argument to
1675 ** xRealloc is always a value returned by a prior call to xRoundup.
1677 ** xSize should return the allocated size of a memory allocation
1678 ** previously obtained from xMalloc or xRealloc. The allocated size
1679 ** is always at least as big as the requested size but may be larger.
1681 ** The xRoundup method returns what would be the allocated size of
1682 ** a memory allocation given a particular requested size. Most memory
1683 ** allocators round up memory allocations at least to the next multiple
1684 ** of 8. Some allocators round up to a larger multiple or to a power of 2.
1685 ** Every memory allocation request coming in through [sqlite3_malloc()]
1686 ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
1687 ** that causes the corresponding memory allocation to fail.
1689 ** The xInit method initializes the memory allocator. For example,
1690 ** it might allocate any require mutexes or initialize internal data
1691 ** structures. The xShutdown method is invoked (indirectly) by
1692 ** [sqlite3_shutdown()] and should deallocate any resources acquired
1693 ** by xInit. The pAppData pointer is used as the only parameter to
1694 ** xInit and xShutdown.
1696 ** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
1697 ** the xInit method, so the xInit method need not be threadsafe. The
1698 ** xShutdown method is only called from [sqlite3_shutdown()] so it does
1699 ** not need to be threadsafe either. For all other methods, SQLite
1700 ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1701 ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1702 ** it is by default) and so the methods are automatically serialized.
1703 ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1704 ** methods must be threadsafe or else make their own arrangements for
1707 ** SQLite will never invoke xInit() more than once without an intervening
1708 ** call to xShutdown().
1710 typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1711 struct sqlite3_mem_methods {
1712 void *(*xMalloc)(int); /* Memory allocation function */
1713 void (*xFree)(void*); /* Free a prior allocation */
1714 void *(*xRealloc)(void*,int); /* Resize an allocation */
1715 int (*xSize)(void*); /* Return the size of an allocation */
1716 int (*xRoundup)(int); /* Round up request size to allocation size */
1717 int (*xInit)(void*); /* Initialize the memory allocator */
1718 void (*xShutdown)(void*); /* Deinitialize the memory allocator */
1719 void *pAppData; /* Argument to xInit() and xShutdown() */
1723 ** CAPI3REF: Configuration Options
1724 ** KEYWORDS: {configuration option}
1726 ** These constants are the available integer configuration options that
1727 ** can be passed as the first argument to the [sqlite3_config()] interface.
1729 ** New configuration options may be added in future releases of SQLite.
1730 ** Existing configuration options might be discontinued. Applications
1731 ** should check the return code from [sqlite3_config()] to make sure that
1732 ** the call worked. The [sqlite3_config()] interface will return a
1733 ** non-zero [error code] if a discontinued or unsupported configuration option
1737 ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1738 ** <dd>There are no arguments to this option. ^This option sets the
1739 ** [threading mode] to Single-thread. In other words, it disables
1740 ** all mutexing and puts SQLite into a mode where it can only be used
1741 ** by a single thread. ^If SQLite is compiled with
1742 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1743 ** it is not possible to change the [threading mode] from its default
1744 ** value of Single-thread and so [sqlite3_config()] will return
1745 ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1746 ** configuration option.</dd>
1748 ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1749 ** <dd>There are no arguments to this option. ^This option sets the
1750 ** [threading mode] to Multi-thread. In other words, it disables
1751 ** mutexing on [database connection] and [prepared statement] objects.
1752 ** The application is responsible for serializing access to
1753 ** [database connections] and [prepared statements]. But other mutexes
1754 ** are enabled so that SQLite will be safe to use in a multi-threaded
1755 ** environment as long as no two threads attempt to use the same
1756 ** [database connection] at the same time. ^If SQLite is compiled with
1757 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1758 ** it is not possible to set the Multi-thread [threading mode] and
1759 ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1760 ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
1762 ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
1763 ** <dd>There are no arguments to this option. ^This option sets the
1764 ** [threading mode] to Serialized. In other words, this option enables
1765 ** all mutexes including the recursive
1766 ** mutexes on [database connection] and [prepared statement] objects.
1767 ** In this mode (which is the default when SQLite is compiled with
1768 ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1769 ** to [database connections] and [prepared statements] so that the
1770 ** application is free to use the same [database connection] or the
1771 ** same [prepared statement] in different threads at the same time.
1772 ** ^If SQLite is compiled with
1773 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1774 ** it is not possible to set the Serialized [threading mode] and
1775 ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1776 ** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
1778 ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
1779 ** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is
1780 ** a pointer to an instance of the [sqlite3_mem_methods] structure.
1781 ** The argument specifies
1782 ** alternative low-level memory allocation routines to be used in place of
1783 ** the memory allocation routines built into SQLite.)^ ^SQLite makes
1784 ** its own private copy of the content of the [sqlite3_mem_methods] structure
1785 ** before the [sqlite3_config()] call returns.</dd>
1787 ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
1788 ** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
1789 ** is a pointer to an instance of the [sqlite3_mem_methods] structure.
1790 ** The [sqlite3_mem_methods]
1791 ** structure is filled with the currently defined memory allocation routines.)^
1792 ** This option can be used to overload the default memory allocation
1793 ** routines with a wrapper that simulations memory allocation failure or
1794 ** tracks memory usage, for example. </dd>
1796 ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1797 ** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,
1798 ** interpreted as a boolean, which enables or disables the collection of
1799 ** memory allocation statistics. ^(When memory allocation statistics are
1800 ** disabled, the following SQLite interfaces become non-operational:
1802 ** <li> [sqlite3_memory_used()]
1803 ** <li> [sqlite3_memory_highwater()]
1804 ** <li> [sqlite3_soft_heap_limit64()]
1805 ** <li> [sqlite3_status64()]
1807 ** ^Memory allocation statistics are enabled by default unless SQLite is
1808 ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1809 ** allocation statistics are disabled by default.
1812 ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
1813 ** <dd> ^The SQLITE_CONFIG_SCRATCH option specifies a static memory buffer
1814 ** that SQLite can use for scratch memory. ^(There are three arguments
1815 ** to SQLITE_CONFIG_SCRATCH: A pointer an 8-byte
1816 ** aligned memory buffer from which the scratch allocations will be
1817 ** drawn, the size of each scratch allocation (sz),
1818 ** and the maximum number of scratch allocations (N).)^
1819 ** The first argument must be a pointer to an 8-byte aligned buffer
1820 ** of at least sz*N bytes of memory.
1821 ** ^SQLite will not use more than one scratch buffers per thread.
1822 ** ^SQLite will never request a scratch buffer that is more than 6
1823 ** times the database page size.
1824 ** ^If SQLite needs needs additional
1825 ** scratch memory beyond what is provided by this configuration option, then
1826 ** [sqlite3_malloc()] will be used to obtain the memory needed.<p>
1827 ** ^When the application provides any amount of scratch memory using
1828 ** SQLITE_CONFIG_SCRATCH, SQLite avoids unnecessary large
1829 ** [sqlite3_malloc|heap allocations].
1830 ** This can help [Robson proof|prevent memory allocation failures] due to heap
1831 ** fragmentation in low-memory embedded systems.
1834 ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
1835 ** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
1836 ** that SQLite can use for the database page cache with the default page
1837 ** cache implementation.
1838 ** This configuration option is a no-op if an application-define page
1839 ** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].
1840 ** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
1841 ** 8-byte aligned memory (pMem), the size of each page cache line (sz),
1842 ** and the number of cache lines (N).
1843 ** The sz argument should be the size of the largest database page
1844 ** (a power of two between 512 and 65536) plus some extra bytes for each
1845 ** page header. ^The number of extra bytes needed by the page header
1846 ** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].
1847 ** ^It is harmless, apart from the wasted memory,
1848 ** for the sz parameter to be larger than necessary. The pMem
1849 ** argument must be either a NULL pointer or a pointer to an 8-byte
1850 ** aligned block of memory of at least sz*N bytes, otherwise
1851 ** subsequent behavior is undefined.
1852 ** ^When pMem is not NULL, SQLite will strive to use the memory provided
1853 ** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
1854 ** a page cache line is larger than sz bytes or if all of the pMem buffer
1856 ** ^If pMem is NULL and N is non-zero, then each database connection
1857 ** does an initial bulk allocation for page cache memory
1858 ** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
1859 ** of -1024*N bytes if N is negative, . ^If additional
1860 ** page cache memory is needed beyond what is provided by the initial
1861 ** allocation, then SQLite goes to [sqlite3_malloc()] separately for each
1862 ** additional cache line. </dd>
1864 ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
1865 ** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer
1866 ** that SQLite will use for all of its dynamic memory allocation needs
1867 ** beyond those provided for by [SQLITE_CONFIG_SCRATCH] and
1868 ** [SQLITE_CONFIG_PAGECACHE].
1869 ** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
1870 ** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
1871 ** [SQLITE_ERROR] if invoked otherwise.
1872 ** ^There are three arguments to SQLITE_CONFIG_HEAP:
1873 ** An 8-byte aligned pointer to the memory,
1874 ** the number of bytes in the memory buffer, and the minimum allocation size.
1875 ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
1876 ** to using its default memory allocator (the system malloc() implementation),
1877 ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
1878 ** memory pointer is not NULL then the alternative memory
1879 ** allocator is engaged to handle all of SQLites memory allocation needs.
1880 ** The first pointer (the memory pointer) must be aligned to an 8-byte
1881 ** boundary or subsequent behavior of SQLite will be undefined.
1882 ** The minimum allocation size is capped at 2**12. Reasonable values
1883 ** for the minimum allocation size are 2**5 through 2**8.</dd>
1885 ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
1886 ** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
1887 ** pointer to an instance of the [sqlite3_mutex_methods] structure.
1888 ** The argument specifies alternative low-level mutex routines to be used
1889 ** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of
1890 ** the content of the [sqlite3_mutex_methods] structure before the call to
1891 ** [sqlite3_config()] returns. ^If SQLite is compiled with
1892 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1893 ** the entire mutexing subsystem is omitted from the build and hence calls to
1894 ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1895 ** return [SQLITE_ERROR].</dd>
1897 ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
1898 ** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
1899 ** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The
1900 ** [sqlite3_mutex_methods]
1901 ** structure is filled with the currently defined mutex routines.)^
1902 ** This option can be used to overload the default mutex allocation
1903 ** routines with a wrapper used to track mutex usage for performance
1904 ** profiling or testing, for example. ^If SQLite is compiled with
1905 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1906 ** the entire mutexing subsystem is omitted from the build and hence calls to
1907 ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1908 ** return [SQLITE_ERROR].</dd>
1910 ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1911 ** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
1912 ** the default size of lookaside memory on each [database connection].
1913 ** The first argument is the
1914 ** size of each lookaside buffer slot and the second is the number of
1915 ** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE
1916 ** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
1917 ** option to [sqlite3_db_config()] can be used to change the lookaside
1918 ** configuration on individual connections.)^ </dd>
1920 ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
1921 ** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is
1922 ** a pointer to an [sqlite3_pcache_methods2] object. This object specifies
1923 ** the interface to a custom page cache implementation.)^
1924 ** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>
1926 ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
1927 ** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
1928 ** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of
1929 ** the current page cache implementation into that object.)^ </dd>
1931 ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
1932 ** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
1933 ** global [error log].
1934 ** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
1935 ** function with a call signature of void(*)(void*,int,const char*),
1936 ** and a pointer to void. ^If the function pointer is not NULL, it is
1937 ** invoked by [sqlite3_log()] to process each logging event. ^If the
1938 ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
1939 ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
1940 ** passed through as the first parameter to the application-defined logger
1941 ** function whenever that function is invoked. ^The second parameter to
1942 ** the logger function is a copy of the first parameter to the corresponding
1943 ** [sqlite3_log()] call and is intended to be a [result code] or an
1944 ** [extended result code]. ^The third parameter passed to the logger is
1945 ** log message after formatting via [sqlite3_snprintf()].
1946 ** The SQLite logging interface is not reentrant; the logger function
1947 ** supplied by the application must not invoke any SQLite interface.
1948 ** In a multi-threaded application, the application-defined logger
1949 ** function must be threadsafe. </dd>
1951 ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
1952 ** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int.
1953 ** If non-zero, then URI handling is globally enabled. If the parameter is zero,
1954 ** then URI handling is globally disabled.)^ ^If URI handling is globally
1955 ** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],
1956 ** [sqlite3_open16()] or
1957 ** specified as part of [ATTACH] commands are interpreted as URIs, regardless
1958 ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
1959 ** connection is opened. ^If it is globally disabled, filenames are
1960 ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
1961 ** database connection is opened. ^(By default, URI handling is globally
1962 ** disabled. The default value may be changed by compiling with the
1963 ** [SQLITE_USE_URI] symbol defined.)^
1965 ** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
1966 ** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer
1967 ** argument which is interpreted as a boolean in order to enable or disable
1968 ** the use of covering indices for full table scans in the query optimizer.
1969 ** ^The default setting is determined
1970 ** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
1971 ** if that compile-time option is omitted.
1972 ** The ability to disable the use of covering indices for full table scans
1973 ** is because some incorrectly coded legacy applications might malfunction
1974 ** when the optimization is enabled. Providing the ability to
1975 ** disable the optimization allows the older, buggy application code to work
1976 ** without change even with newer versions of SQLite.
1978 ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
1979 ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
1980 ** <dd> These options are obsolete and should not be used by new code.
1981 ** They are retained for backwards compatibility but are now no-ops.
1984 ** [[SQLITE_CONFIG_SQLLOG]]
1985 ** <dt>SQLITE_CONFIG_SQLLOG
1986 ** <dd>This option is only available if sqlite is compiled with the
1987 ** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
1988 ** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
1989 ** The second should be of type (void*). The callback is invoked by the library
1990 ** in three separate circumstances, identified by the value passed as the
1991 ** fourth parameter. If the fourth parameter is 0, then the database connection
1992 ** passed as the second argument has just been opened. The third argument
1993 ** points to a buffer containing the name of the main database file. If the
1994 ** fourth parameter is 1, then the SQL statement that the third parameter
1995 ** points to has just been executed. Or, if the fourth parameter is 2, then
1996 ** the connection being passed as the second parameter is being closed. The
1997 ** third parameter is passed NULL In this case. An example of using this
1998 ** configuration option can be seen in the "test_sqllog.c" source file in
1999 ** the canonical SQLite source tree.</dd>
2001 ** [[SQLITE_CONFIG_MMAP_SIZE]]
2002 ** <dt>SQLITE_CONFIG_MMAP_SIZE
2003 ** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
2004 ** that are the default mmap size limit (the default setting for
2005 ** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
2006 ** ^The default setting can be overridden by each database connection using
2007 ** either the [PRAGMA mmap_size] command, or by using the
2008 ** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size
2009 ** will be silently truncated if necessary so that it does not exceed the
2010 ** compile-time maximum mmap size set by the
2011 ** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
2012 ** ^If either argument to this option is negative, then that argument is
2013 ** changed to its compile-time default.
2015 ** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
2016 ** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
2017 ** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
2018 ** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
2019 ** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
2020 ** that specifies the maximum size of the created heap.
2022 ** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
2023 ** <dt>SQLITE_CONFIG_PCACHE_HDRSZ
2024 ** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
2025 ** is a pointer to an integer and writes into that integer the number of extra
2026 ** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
2027 ** The amount of extra space required can change depending on the compiler,
2028 ** target platform, and SQLite version.
2030 ** [[SQLITE_CONFIG_PMASZ]]
2031 ** <dt>SQLITE_CONFIG_PMASZ
2032 ** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which
2033 ** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
2034 ** sorter to that integer. The default minimum PMA Size is set by the
2035 ** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched
2036 ** to help with sort operations when multithreaded sorting
2037 ** is enabled (using the [PRAGMA threads] command) and the amount of content
2038 ** to be sorted exceeds the page size times the minimum of the
2039 ** [PRAGMA cache_size] setting and this value.
2042 #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
2043 #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
2044 #define SQLITE_CONFIG_SERIALIZED 3 /* nil */
2045 #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
2046 #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
2047 #define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */
2048 #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
2049 #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
2050 #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
2051 #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
2052 #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
2053 /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
2054 #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
2055 #define SQLITE_CONFIG_PCACHE 14 /* no-op */
2056 #define SQLITE_CONFIG_GETPCACHE 15 /* no-op */
2057 #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
2058 #define SQLITE_CONFIG_URI 17 /* int */
2059 #define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */
2060 #define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */
2061 #define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */
2062 #define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */
2063 #define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */
2064 #define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */
2065 #define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */
2066 #define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */
2069 ** CAPI3REF: Database Connection Configuration Options
2071 ** These constants are the available integer configuration options that
2072 ** can be passed as the second argument to the [sqlite3_db_config()] interface.
2074 ** New configuration options may be added in future releases of SQLite.
2075 ** Existing configuration options might be discontinued. Applications
2076 ** should check the return code from [sqlite3_db_config()] to make sure that
2077 ** the call worked. ^The [sqlite3_db_config()] interface will return a
2078 ** non-zero [error code] if a discontinued or unsupported configuration option
2082 ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
2083 ** <dd> ^This option takes three additional arguments that determine the
2084 ** [lookaside memory allocator] configuration for the [database connection].
2085 ** ^The first argument (the third parameter to [sqlite3_db_config()] is a
2086 ** pointer to a memory buffer to use for lookaside memory.
2087 ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
2088 ** may be NULL in which case SQLite will allocate the
2089 ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
2090 ** size of each lookaside buffer slot. ^The third argument is the number of
2091 ** slots. The size of the buffer in the first argument must be greater than
2092 ** or equal to the product of the second and third arguments. The buffer
2093 ** must be aligned to an 8-byte boundary. ^If the second argument to
2094 ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
2095 ** rounded down to the next smaller multiple of 8. ^(The lookaside memory
2096 ** configuration for a database connection can only be changed when that
2097 ** connection is not currently using lookaside memory, or in other words
2098 ** when the "current value" returned by
2099 ** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
2100 ** Any attempt to change the lookaside memory configuration when lookaside
2101 ** memory is in use leaves the configuration unchanged and returns
2102 ** [SQLITE_BUSY].)^</dd>
2104 ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
2105 ** <dd> ^This option is used to enable or disable the enforcement of
2106 ** [foreign key constraints]. There should be two additional arguments.
2107 ** The first argument is an integer which is 0 to disable FK enforcement,
2108 ** positive to enable FK enforcement or negative to leave FK enforcement
2109 ** unchanged. The second parameter is a pointer to an integer into which
2110 ** is written 0 or 1 to indicate whether FK enforcement is off or on
2111 ** following this call. The second parameter may be a NULL pointer, in
2112 ** which case the FK enforcement setting is not reported back. </dd>
2114 ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
2115 ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
2116 ** There should be two additional arguments.
2117 ** The first argument is an integer which is 0 to disable triggers,
2118 ** positive to enable triggers or negative to leave the setting unchanged.
2119 ** The second parameter is a pointer to an integer into which
2120 ** is written 0 or 1 to indicate whether triggers are disabled or enabled
2121 ** following this call. The second parameter may be a NULL pointer, in
2122 ** which case the trigger setting is not reported back. </dd>
2126 #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
2127 #define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */
2128 #define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */
2132 ** CAPI3REF: Enable Or Disable Extended Result Codes
2135 ** ^The sqlite3_extended_result_codes() routine enables or disables the
2136 ** [extended result codes] feature of SQLite. ^The extended result
2137 ** codes are disabled by default for historical compatibility.
2139 SQLITE_API int SQLITE_STDCALL sqlite3_extended_result_codes(sqlite3*, int onoff);
2142 ** CAPI3REF: Last Insert Rowid
2145 ** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
2146 ** has a unique 64-bit signed
2147 ** integer key called the [ROWID | "rowid"]. ^The rowid is always available
2148 ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
2149 ** names are not also used by explicitly declared columns. ^If
2150 ** the table has a column of type [INTEGER PRIMARY KEY] then that column
2151 ** is another alias for the rowid.
2153 ** ^The sqlite3_last_insert_rowid(D) interface returns the [rowid] of the
2154 ** most recent successful [INSERT] into a rowid table or [virtual table]
2155 ** on database connection D.
2156 ** ^Inserts into [WITHOUT ROWID] tables are not recorded.
2157 ** ^If no successful [INSERT]s into rowid tables
2158 ** have ever occurred on the database connection D,
2159 ** then sqlite3_last_insert_rowid(D) returns zero.
2161 ** ^(If an [INSERT] occurs within a trigger or within a [virtual table]
2162 ** method, then this routine will return the [rowid] of the inserted
2163 ** row as long as the trigger or virtual table method is running.
2164 ** But once the trigger or virtual table method ends, the value returned
2165 ** by this routine reverts to what it was before the trigger or virtual
2166 ** table method began.)^
2168 ** ^An [INSERT] that fails due to a constraint violation is not a
2169 ** successful [INSERT] and does not change the value returned by this
2170 ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
2171 ** and INSERT OR ABORT make no changes to the return value of this
2172 ** routine when their insertion fails. ^(When INSERT OR REPLACE
2173 ** encounters a constraint violation, it does not fail. The
2174 ** INSERT continues to completion after deleting rows that caused
2175 ** the constraint problem so INSERT OR REPLACE will always change
2176 ** the return value of this interface.)^
2178 ** ^For the purposes of this routine, an [INSERT] is considered to
2179 ** be successful even if it is subsequently rolled back.
2181 ** This function is accessible to SQL statements via the
2182 ** [last_insert_rowid() SQL function].
2184 ** If a separate thread performs a new [INSERT] on the same
2185 ** database connection while the [sqlite3_last_insert_rowid()]
2186 ** function is running and thus changes the last insert [rowid],
2187 ** then the value returned by [sqlite3_last_insert_rowid()] is
2188 ** unpredictable and might not equal either the old or the new
2189 ** last insert [rowid].
2191 SQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_last_insert_rowid(sqlite3*);
2194 ** CAPI3REF: Count The Number Of Rows Modified
2197 ** ^This function returns the number of rows modified, inserted or
2198 ** deleted by the most recently completed INSERT, UPDATE or DELETE
2199 ** statement on the database connection specified by the only parameter.
2200 ** ^Executing any other type of SQL statement does not modify the value
2201 ** returned by this function.
2203 ** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
2204 ** considered - auxiliary changes caused by [CREATE TRIGGER | triggers],
2205 ** [foreign key actions] or [REPLACE] constraint resolution are not counted.
2207 ** Changes to a view that are intercepted by
2208 ** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value
2209 ** returned by sqlite3_changes() immediately after an INSERT, UPDATE or
2210 ** DELETE statement run on a view is always zero. Only changes made to real
2211 ** tables are counted.
2213 ** Things are more complicated if the sqlite3_changes() function is
2214 ** executed while a trigger program is running. This may happen if the
2215 ** program uses the [changes() SQL function], or if some other callback
2216 ** function invokes sqlite3_changes() directly. Essentially:
2219 ** <li> ^(Before entering a trigger program the value returned by
2220 ** sqlite3_changes() function is saved. After the trigger program
2221 ** has finished, the original value is restored.)^
2223 ** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE
2224 ** statement sets the value returned by sqlite3_changes()
2225 ** upon completion as normal. Of course, this value will not include
2226 ** any changes performed by sub-triggers, as the sqlite3_changes()
2227 ** value will be saved and restored after each sub-trigger has run.)^
2230 ** ^This means that if the changes() SQL function (or similar) is used
2231 ** by the first INSERT, UPDATE or DELETE statement within a trigger, it
2232 ** returns the value as set when the calling statement began executing.
2233 ** ^If it is used by the second or subsequent such statement within a trigger
2234 ** program, the value returned reflects the number of rows modified by the
2235 ** previous INSERT, UPDATE or DELETE statement within the same trigger.
2237 ** See also the [sqlite3_total_changes()] interface, the
2238 ** [count_changes pragma], and the [changes() SQL function].
2240 ** If a separate thread makes changes on the same database connection
2241 ** while [sqlite3_changes()] is running then the value returned
2242 ** is unpredictable and not meaningful.
2244 SQLITE_API int SQLITE_STDCALL sqlite3_changes(sqlite3*);
2247 ** CAPI3REF: Total Number Of Rows Modified
2250 ** ^This function returns the total number of rows inserted, modified or
2251 ** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
2252 ** since the database connection was opened, including those executed as
2253 ** part of trigger programs. ^Executing any other type of SQL statement
2254 ** does not affect the value returned by sqlite3_total_changes().
2256 ** ^Changes made as part of [foreign key actions] are included in the
2257 ** count, but those made as part of REPLACE constraint resolution are
2258 ** not. ^Changes to a view that are intercepted by INSTEAD OF triggers
2261 ** See also the [sqlite3_changes()] interface, the
2262 ** [count_changes pragma], and the [total_changes() SQL function].
2264 ** If a separate thread makes changes on the same database connection
2265 ** while [sqlite3_total_changes()] is running then the value
2266 ** returned is unpredictable and not meaningful.
2268 SQLITE_API int SQLITE_STDCALL sqlite3_total_changes(sqlite3*);
2271 ** CAPI3REF: Interrupt A Long-Running Query
2274 ** ^This function causes any pending database operation to abort and
2275 ** return at its earliest opportunity. This routine is typically
2276 ** called in response to a user action such as pressing "Cancel"
2277 ** or Ctrl-C where the user wants a long query operation to halt
2280 ** ^It is safe to call this routine from a thread different from the
2281 ** thread that is currently running the database operation. But it
2282 ** is not safe to call this routine with a [database connection] that
2283 ** is closed or might close before sqlite3_interrupt() returns.
2285 ** ^If an SQL operation is very nearly finished at the time when
2286 ** sqlite3_interrupt() is called, then it might not have an opportunity
2287 ** to be interrupted and might continue to completion.
2289 ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
2290 ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
2291 ** that is inside an explicit transaction, then the entire transaction
2292 ** will be rolled back automatically.
2294 ** ^The sqlite3_interrupt(D) call is in effect until all currently running
2295 ** SQL statements on [database connection] D complete. ^Any new SQL statements
2296 ** that are started after the sqlite3_interrupt() call and before the
2297 ** running statements reaches zero are interrupted as if they had been
2298 ** running prior to the sqlite3_interrupt() call. ^New SQL statements
2299 ** that are started after the running statement count reaches zero are
2300 ** not effected by the sqlite3_interrupt().
2301 ** ^A call to sqlite3_interrupt(D) that occurs when there are no running
2302 ** SQL statements is a no-op and has no effect on SQL statements
2303 ** that are started after the sqlite3_interrupt() call returns.
2305 ** If the database connection closes while [sqlite3_interrupt()]
2306 ** is running then bad things will likely happen.
2308 SQLITE_API void SQLITE_STDCALL sqlite3_interrupt(sqlite3*);
2311 ** CAPI3REF: Determine If An SQL Statement Is Complete
2313 ** These routines are useful during command-line input to determine if the
2314 ** currently entered text seems to form a complete SQL statement or
2315 ** if additional input is needed before sending the text into
2316 ** SQLite for parsing. ^These routines return 1 if the input string
2317 ** appears to be a complete SQL statement. ^A statement is judged to be
2318 ** complete if it ends with a semicolon token and is not a prefix of a
2319 ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
2320 ** string literals or quoted identifier names or comments are not
2321 ** independent tokens (they are part of the token in which they are
2322 ** embedded) and thus do not count as a statement terminator. ^Whitespace
2323 ** and comments that follow the final semicolon are ignored.
2325 ** ^These routines return 0 if the statement is incomplete. ^If a
2326 ** memory allocation fails, then SQLITE_NOMEM is returned.
2328 ** ^These routines do not parse the SQL statements thus
2329 ** will not detect syntactically incorrect SQL.
2331 ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
2332 ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
2333 ** automatically by sqlite3_complete16(). If that initialization fails,
2334 ** then the return value from sqlite3_complete16() will be non-zero
2335 ** regardless of whether or not the input SQL is complete.)^
2337 ** The input to [sqlite3_complete()] must be a zero-terminated
2340 ** The input to [sqlite3_complete16()] must be a zero-terminated
2341 ** UTF-16 string in native byte order.
2343 SQLITE_API int SQLITE_STDCALL sqlite3_complete(const char *sql);
2344 SQLITE_API int SQLITE_STDCALL sqlite3_complete16(const void *sql);
2347 ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
2348 ** KEYWORDS: {busy-handler callback} {busy handler}
2351 ** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
2352 ** that might be invoked with argument P whenever
2353 ** an attempt is made to access a database table associated with
2354 ** [database connection] D when another thread
2355 ** or process has the table locked.
2356 ** The sqlite3_busy_handler() interface is used to implement
2357 ** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
2359 ** ^If the busy callback is NULL, then [SQLITE_BUSY]
2360 ** is returned immediately upon encountering the lock. ^If the busy callback
2361 ** is not NULL, then the callback might be invoked with two arguments.
2363 ** ^The first argument to the busy handler is a copy of the void* pointer which
2364 ** is the third argument to sqlite3_busy_handler(). ^The second argument to
2365 ** the busy handler callback is the number of times that the busy handler has
2366 ** been invoked previously for the same locking event. ^If the
2367 ** busy callback returns 0, then no additional attempts are made to
2368 ** access the database and [SQLITE_BUSY] is returned
2369 ** to the application.
2370 ** ^If the callback returns non-zero, then another attempt
2371 ** is made to access the database and the cycle repeats.
2373 ** The presence of a busy handler does not guarantee that it will be invoked
2374 ** when there is lock contention. ^If SQLite determines that invoking the busy
2375 ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
2376 ** to the application instead of invoking the
2378 ** Consider a scenario where one process is holding a read lock that
2379 ** it is trying to promote to a reserved lock and
2380 ** a second process is holding a reserved lock that it is trying
2381 ** to promote to an exclusive lock. The first process cannot proceed
2382 ** because it is blocked by the second and the second process cannot
2383 ** proceed because it is blocked by the first. If both processes
2384 ** invoke the busy handlers, neither will make any progress. Therefore,
2385 ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
2386 ** will induce the first process to release its read lock and allow
2387 ** the second process to proceed.
2389 ** ^The default busy callback is NULL.
2391 ** ^(There can only be a single busy handler defined for each
2392 ** [database connection]. Setting a new busy handler clears any
2393 ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
2394 ** or evaluating [PRAGMA busy_timeout=N] will change the
2395 ** busy handler and thus clear any previously set busy handler.
2397 ** The busy callback should not take any actions which modify the
2398 ** database connection that invoked the busy handler. In other words,
2399 ** the busy handler is not reentrant. Any such actions
2400 ** result in undefined behavior.
2402 ** A busy handler must not close the database connection
2403 ** or [prepared statement] that invoked the busy handler.
2405 SQLITE_API int SQLITE_STDCALL sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
2408 ** CAPI3REF: Set A Busy Timeout
2411 ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
2412 ** for a specified amount of time when a table is locked. ^The handler
2413 ** will sleep multiple times until at least "ms" milliseconds of sleeping
2414 ** have accumulated. ^After at least "ms" milliseconds of sleeping,
2415 ** the handler returns 0 which causes [sqlite3_step()] to return
2418 ** ^Calling this routine with an argument less than or equal to zero
2419 ** turns off all busy handlers.
2421 ** ^(There can only be a single busy handler for a particular
2422 ** [database connection] at any given moment. If another busy handler
2423 ** was defined (using [sqlite3_busy_handler()]) prior to calling
2424 ** this routine, that other busy handler is cleared.)^
2426 ** See also: [PRAGMA busy_timeout]
2428 SQLITE_API int SQLITE_STDCALL sqlite3_busy_timeout(sqlite3*, int ms);
2431 ** CAPI3REF: Convenience Routines For Running Queries
2434 ** This is a legacy interface that is preserved for backwards compatibility.
2435 ** Use of this interface is not recommended.
2437 ** Definition: A <b>result table</b> is memory data structure created by the
2438 ** [sqlite3_get_table()] interface. A result table records the
2439 ** complete query results from one or more queries.
2441 ** The table conceptually has a number of rows and columns. But
2442 ** these numbers are not part of the result table itself. These
2443 ** numbers are obtained separately. Let N be the number of rows
2444 ** and M be the number of columns.
2446 ** A result table is an array of pointers to zero-terminated UTF-8 strings.
2447 ** There are (N+1)*M elements in the array. The first M pointers point
2448 ** to zero-terminated strings that contain the names of the columns.
2449 ** The remaining entries all point to query results. NULL values result
2450 ** in NULL pointers. All other values are in their UTF-8 zero-terminated
2451 ** string representation as returned by [sqlite3_column_text()].
2453 ** A result table might consist of one or more memory allocations.
2454 ** It is not safe to pass a result table directly to [sqlite3_free()].
2455 ** A result table should be deallocated using [sqlite3_free_table()].
2457 ** ^(As an example of the result table format, suppose a query result
2460 ** <blockquote><pre>
2462 ** -----------------------
2466 ** </pre></blockquote>
2468 ** There are two column (M==2) and three rows (N==3). Thus the
2469 ** result table has 8 entries. Suppose the result table is stored
2470 ** in an array names azResult. Then azResult holds this content:
2472 ** <blockquote><pre>
2473 ** azResult[0] = "Name";
2474 ** azResult[1] = "Age";
2475 ** azResult[2] = "Alice";
2476 ** azResult[3] = "43";
2477 ** azResult[4] = "Bob";
2478 ** azResult[5] = "28";
2479 ** azResult[6] = "Cindy";
2480 ** azResult[7] = "21";
2481 ** </pre></blockquote>)^
2483 ** ^The sqlite3_get_table() function evaluates one or more
2484 ** semicolon-separated SQL statements in the zero-terminated UTF-8
2485 ** string of its 2nd parameter and returns a result table to the
2486 ** pointer given in its 3rd parameter.
2488 ** After the application has finished with the result from sqlite3_get_table(),
2489 ** it must pass the result table pointer to sqlite3_free_table() in order to
2490 ** release the memory that was malloced. Because of the way the
2491 ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
2492 ** function must not try to call [sqlite3_free()] directly. Only
2493 ** [sqlite3_free_table()] is able to release the memory properly and safely.
2495 ** The sqlite3_get_table() interface is implemented as a wrapper around
2496 ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
2497 ** to any internal data structures of SQLite. It uses only the public
2498 ** interface defined here. As a consequence, errors that occur in the
2499 ** wrapper layer outside of the internal [sqlite3_exec()] call are not
2500 ** reflected in subsequent calls to [sqlite3_errcode()] or
2501 ** [sqlite3_errmsg()].
2503 SQLITE_API int SQLITE_STDCALL sqlite3_get_table(
2504 sqlite3 *db, /* An open database */
2505 const char *zSql, /* SQL to be evaluated */
2506 char ***pazResult, /* Results of the query */
2507 int *pnRow, /* Number of result rows written here */
2508 int *pnColumn, /* Number of result columns written here */
2509 char **pzErrmsg /* Error msg written here */
2511 SQLITE_API void SQLITE_STDCALL sqlite3_free_table(char **result);
2514 ** CAPI3REF: Formatted String Printing Functions
2516 ** These routines are work-alikes of the "printf()" family of functions
2517 ** from the standard C library.
2518 ** These routines understand most of the common K&R formatting options,
2519 ** plus some additional non-standard formats, detailed below.
2520 ** Note that some of the more obscure formatting options from recent
2521 ** C-library standards are omitted from this implementation.
2523 ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
2524 ** results into memory obtained from [sqlite3_malloc()].
2525 ** The strings returned by these two routines should be
2526 ** released by [sqlite3_free()]. ^Both routines return a
2527 ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
2528 ** memory to hold the resulting string.
2530 ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
2531 ** the standard C library. The result is written into the
2532 ** buffer supplied as the second parameter whose size is given by
2533 ** the first parameter. Note that the order of the
2534 ** first two parameters is reversed from snprintf().)^ This is an
2535 ** historical accident that cannot be fixed without breaking
2536 ** backwards compatibility. ^(Note also that sqlite3_snprintf()
2537 ** returns a pointer to its buffer instead of the number of
2538 ** characters actually written into the buffer.)^ We admit that
2539 ** the number of characters written would be a more useful return
2540 ** value but we cannot change the implementation of sqlite3_snprintf()
2541 ** now without breaking compatibility.
2543 ** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
2544 ** guarantees that the buffer is always zero-terminated. ^The first
2545 ** parameter "n" is the total size of the buffer, including space for
2546 ** the zero terminator. So the longest string that can be completely
2547 ** written will be n-1 characters.
2549 ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
2551 ** These routines all implement some additional formatting
2552 ** options that are useful for constructing SQL statements.
2553 ** All of the usual printf() formatting options apply. In addition, there
2554 ** is are "%q", "%Q", "%w" and "%z" options.
2556 ** ^(The %q option works like %s in that it substitutes a nul-terminated
2557 ** string from the argument list. But %q also doubles every '\'' character.
2558 ** %q is designed for use inside a string literal.)^ By doubling each '\''
2559 ** character it escapes that character and allows it to be inserted into
2562 ** For example, assume the string variable zText contains text as follows:
2564 ** <blockquote><pre>
2565 ** char *zText = "It's a happy day!";
2566 ** </pre></blockquote>
2568 ** One can use this text in an SQL statement as follows:
2570 ** <blockquote><pre>
2571 ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
2572 ** sqlite3_exec(db, zSQL, 0, 0, 0);
2573 ** sqlite3_free(zSQL);
2574 ** </pre></blockquote>
2576 ** Because the %q format string is used, the '\'' character in zText
2577 ** is escaped and the SQL generated is as follows:
2579 ** <blockquote><pre>
2580 ** INSERT INTO table1 VALUES('It''s a happy day!')
2581 ** </pre></blockquote>
2583 ** This is correct. Had we used %s instead of %q, the generated SQL
2584 ** would have looked like this:
2586 ** <blockquote><pre>
2587 ** INSERT INTO table1 VALUES('It's a happy day!');
2588 ** </pre></blockquote>
2590 ** This second example is an SQL syntax error. As a general rule you should
2591 ** always use %q instead of %s when inserting text into a string literal.
2593 ** ^(The %Q option works like %q except it also adds single quotes around
2594 ** the outside of the total string. Additionally, if the parameter in the
2595 ** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
2596 ** single quotes).)^ So, for example, one could say:
2598 ** <blockquote><pre>
2599 ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
2600 ** sqlite3_exec(db, zSQL, 0, 0, 0);
2601 ** sqlite3_free(zSQL);
2602 ** </pre></blockquote>
2604 ** The code above will render a correct SQL statement in the zSQL
2605 ** variable even if the zText variable is a NULL pointer.
2607 ** ^(The "%w" formatting option is like "%q" except that it expects to
2608 ** be contained within double-quotes instead of single quotes, and it
2609 ** escapes the double-quote character instead of the single-quote
2610 ** character.)^ The "%w" formatting option is intended for safely inserting
2611 ** table and column names into a constructed SQL statement.
2613 ** ^(The "%z" formatting option works like "%s" but with the
2614 ** addition that after the string has been read and copied into
2615 ** the result, [sqlite3_free()] is called on the input string.)^
2617 SQLITE_API char *SQLITE_CDECL sqlite3_mprintf(const char*,...);
2618 SQLITE_API char *SQLITE_STDCALL sqlite3_vmprintf(const char*, va_list);
2619 SQLITE_API char *SQLITE_CDECL sqlite3_snprintf(int,char*,const char*, ...);
2620 SQLITE_API char *SQLITE_STDCALL sqlite3_vsnprintf(int,char*,const char*, va_list);
2623 ** CAPI3REF: Memory Allocation Subsystem
2625 ** The SQLite core uses these three routines for all of its own
2626 ** internal memory allocation needs. "Core" in the previous sentence
2627 ** does not include operating-system specific VFS implementation. The
2628 ** Windows VFS uses native malloc() and free() for some operations.
2630 ** ^The sqlite3_malloc() routine returns a pointer to a block
2631 ** of memory at least N bytes in length, where N is the parameter.
2632 ** ^If sqlite3_malloc() is unable to obtain sufficient free
2633 ** memory, it returns a NULL pointer. ^If the parameter N to
2634 ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
2637 ** ^The sqlite3_malloc64(N) routine works just like
2638 ** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
2639 ** of a signed 32-bit integer.
2641 ** ^Calling sqlite3_free() with a pointer previously returned
2642 ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
2643 ** that it might be reused. ^The sqlite3_free() routine is
2644 ** a no-op if is called with a NULL pointer. Passing a NULL pointer
2645 ** to sqlite3_free() is harmless. After being freed, memory
2646 ** should neither be read nor written. Even reading previously freed
2647 ** memory might result in a segmentation fault or other severe error.
2648 ** Memory corruption, a segmentation fault, or other severe error
2649 ** might result if sqlite3_free() is called with a non-NULL pointer that
2650 ** was not obtained from sqlite3_malloc() or sqlite3_realloc().
2652 ** ^The sqlite3_realloc(X,N) interface attempts to resize a
2653 ** prior memory allocation X to be at least N bytes.
2654 ** ^If the X parameter to sqlite3_realloc(X,N)
2655 ** is a NULL pointer then its behavior is identical to calling
2656 ** sqlite3_malloc(N).
2657 ** ^If the N parameter to sqlite3_realloc(X,N) is zero or
2658 ** negative then the behavior is exactly the same as calling
2660 ** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
2661 ** of at least N bytes in size or NULL if insufficient memory is available.
2662 ** ^If M is the size of the prior allocation, then min(N,M) bytes
2663 ** of the prior allocation are copied into the beginning of buffer returned
2664 ** by sqlite3_realloc(X,N) and the prior allocation is freed.
2665 ** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
2666 ** prior allocation is not freed.
2668 ** ^The sqlite3_realloc64(X,N) interfaces works the same as
2669 ** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
2670 ** of a 32-bit signed integer.
2672 ** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
2673 ** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
2674 ** sqlite3_msize(X) returns the size of that memory allocation in bytes.
2675 ** ^The value returned by sqlite3_msize(X) might be larger than the number
2676 ** of bytes requested when X was allocated. ^If X is a NULL pointer then
2677 ** sqlite3_msize(X) returns zero. If X points to something that is not
2678 ** the beginning of memory allocation, or if it points to a formerly
2679 ** valid memory allocation that has now been freed, then the behavior
2680 ** of sqlite3_msize(X) is undefined and possibly harmful.
2682 ** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
2683 ** sqlite3_malloc64(), and sqlite3_realloc64()
2684 ** is always aligned to at least an 8 byte boundary, or to a
2685 ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
2688 ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
2689 ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
2690 ** implementation of these routines to be omitted. That capability
2691 ** is no longer provided. Only built-in memory allocators can be used.
2693 ** Prior to SQLite version 3.7.10, the Windows OS interface layer called
2694 ** the system malloc() and free() directly when converting
2695 ** filenames between the UTF-8 encoding used by SQLite
2696 ** and whatever filename encoding is used by the particular Windows
2697 ** installation. Memory allocation errors were detected, but
2698 ** they were reported back as [SQLITE_CANTOPEN] or
2699 ** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
2701 ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
2702 ** must be either NULL or else pointers obtained from a prior
2703 ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
2704 ** not yet been released.
2706 ** The application must not read or write any part of
2707 ** a block of memory after it has been released using
2708 ** [sqlite3_free()] or [sqlite3_realloc()].
2710 SQLITE_API void *SQLITE_STDCALL sqlite3_malloc(int);
2711 SQLITE_API void *SQLITE_STDCALL sqlite3_malloc64(sqlite3_uint64);
2712 SQLITE_API void *SQLITE_STDCALL sqlite3_realloc(void*, int);
2713 SQLITE_API void *SQLITE_STDCALL sqlite3_realloc64(void*, sqlite3_uint64);
2714 SQLITE_API void SQLITE_STDCALL sqlite3_free(void*);
2715 SQLITE_API sqlite3_uint64 SQLITE_STDCALL sqlite3_msize(void*);
2718 ** CAPI3REF: Memory Allocator Statistics
2720 ** SQLite provides these two interfaces for reporting on the status
2721 ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
2722 ** routines, which form the built-in memory allocation subsystem.
2724 ** ^The [sqlite3_memory_used()] routine returns the number of bytes
2725 ** of memory currently outstanding (malloced but not freed).
2726 ** ^The [sqlite3_memory_highwater()] routine returns the maximum
2727 ** value of [sqlite3_memory_used()] since the high-water mark
2728 ** was last reset. ^The values returned by [sqlite3_memory_used()] and
2729 ** [sqlite3_memory_highwater()] include any overhead
2730 ** added by SQLite in its implementation of [sqlite3_malloc()],
2731 ** but not overhead added by the any underlying system library
2732 ** routines that [sqlite3_malloc()] may call.
2734 ** ^The memory high-water mark is reset to the current value of
2735 ** [sqlite3_memory_used()] if and only if the parameter to
2736 ** [sqlite3_memory_highwater()] is true. ^The value returned
2737 ** by [sqlite3_memory_highwater(1)] is the high-water mark
2738 ** prior to the reset.
2740 SQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_memory_used(void);
2741 SQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_memory_highwater(int resetFlag);
2744 ** CAPI3REF: Pseudo-Random Number Generator
2746 ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
2747 ** select random [ROWID | ROWIDs] when inserting new records into a table that
2748 ** already uses the largest possible [ROWID]. The PRNG is also used for
2749 ** the build-in random() and randomblob() SQL functions. This interface allows
2750 ** applications to access the same PRNG for other purposes.
2752 ** ^A call to this routine stores N bytes of randomness into buffer P.
2753 ** ^The P parameter can be a NULL pointer.
2755 ** ^If this routine has not been previously called or if the previous
2756 ** call had N less than one or a NULL pointer for P, then the PRNG is
2757 ** seeded using randomness obtained from the xRandomness method of
2758 ** the default [sqlite3_vfs] object.
2759 ** ^If the previous call to this routine had an N of 1 or more and a
2760 ** non-NULL P then the pseudo-randomness is generated
2761 ** internally and without recourse to the [sqlite3_vfs] xRandomness
2764 SQLITE_API void SQLITE_STDCALL sqlite3_randomness(int N, void *P);
2767 ** CAPI3REF: Compile-Time Authorization Callbacks
2770 ** ^This routine registers an authorizer callback with a particular
2771 ** [database connection], supplied in the first argument.
2772 ** ^The authorizer callback is invoked as SQL statements are being compiled
2773 ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
2774 ** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various
2775 ** points during the compilation process, as logic is being created
2776 ** to perform various actions, the authorizer callback is invoked to
2777 ** see if those actions are allowed. ^The authorizer callback should
2778 ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
2779 ** specific action but allow the SQL statement to continue to be
2780 ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
2781 ** rejected with an error. ^If the authorizer callback returns
2782 ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
2783 ** then the [sqlite3_prepare_v2()] or equivalent call that triggered
2784 ** the authorizer will fail with an error message.
2786 ** When the callback returns [SQLITE_OK], that means the operation
2787 ** requested is ok. ^When the callback returns [SQLITE_DENY], the
2788 ** [sqlite3_prepare_v2()] or equivalent call that triggered the
2789 ** authorizer will fail with an error message explaining that
2790 ** access is denied.
2792 ** ^The first parameter to the authorizer callback is a copy of the third
2793 ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
2794 ** to the callback is an integer [SQLITE_COPY | action code] that specifies
2795 ** the particular action to be authorized. ^The third through sixth parameters
2796 ** to the callback are zero-terminated strings that contain additional
2797 ** details about the action to be authorized.
2799 ** ^If the action code is [SQLITE_READ]
2800 ** and the callback returns [SQLITE_IGNORE] then the
2801 ** [prepared statement] statement is constructed to substitute
2802 ** a NULL value in place of the table column that would have
2803 ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
2804 ** return can be used to deny an untrusted user access to individual
2805 ** columns of a table.
2806 ** ^If the action code is [SQLITE_DELETE] and the callback returns
2807 ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
2808 ** [truncate optimization] is disabled and all rows are deleted individually.
2810 ** An authorizer is used when [sqlite3_prepare | preparing]
2811 ** SQL statements from an untrusted source, to ensure that the SQL statements
2812 ** do not try to access data they are not allowed to see, or that they do not
2813 ** try to execute malicious statements that damage the database. For
2814 ** example, an application may allow a user to enter arbitrary
2815 ** SQL queries for evaluation by a database. But the application does
2816 ** not want the user to be able to make arbitrary changes to the
2817 ** database. An authorizer could then be put in place while the
2818 ** user-entered SQL is being [sqlite3_prepare | prepared] that
2819 ** disallows everything except [SELECT] statements.
2821 ** Applications that need to process SQL from untrusted sources
2822 ** might also consider lowering resource limits using [sqlite3_limit()]
2823 ** and limiting database size using the [max_page_count] [PRAGMA]
2824 ** in addition to using an authorizer.
2826 ** ^(Only a single authorizer can be in place on a database connection
2827 ** at a time. Each call to sqlite3_set_authorizer overrides the
2828 ** previous call.)^ ^Disable the authorizer by installing a NULL callback.
2829 ** The authorizer is disabled by default.
2831 ** The authorizer callback must not do anything that will modify
2832 ** the database connection that invoked the authorizer callback.
2833 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2834 ** database connections for the meaning of "modify" in this paragraph.
2836 ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
2837 ** statement might be re-prepared during [sqlite3_step()] due to a
2838 ** schema change. Hence, the application should ensure that the
2839 ** correct authorizer callback remains in place during the [sqlite3_step()].
2841 ** ^Note that the authorizer callback is invoked only during
2842 ** [sqlite3_prepare()] or its variants. Authorization is not
2843 ** performed during statement evaluation in [sqlite3_step()], unless
2844 ** as stated in the previous paragraph, sqlite3_step() invokes
2845 ** sqlite3_prepare_v2() to reprepare a statement after a schema change.
2847 SQLITE_API int SQLITE_STDCALL sqlite3_set_authorizer(
2849 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
2854 ** CAPI3REF: Authorizer Return Codes
2856 ** The [sqlite3_set_authorizer | authorizer callback function] must
2857 ** return either [SQLITE_OK] or one of these two constants in order
2858 ** to signal SQLite whether or not the action is permitted. See the
2859 ** [sqlite3_set_authorizer | authorizer documentation] for additional
2862 ** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
2863 ** returned from the [sqlite3_vtab_on_conflict()] interface.
2865 #define SQLITE_DENY 1 /* Abort the SQL statement with an error */
2866 #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
2869 ** CAPI3REF: Authorizer Action Codes
2871 ** The [sqlite3_set_authorizer()] interface registers a callback function
2872 ** that is invoked to authorize certain SQL statement actions. The
2873 ** second parameter to the callback is an integer code that specifies
2874 ** what action is being authorized. These are the integer action codes that
2875 ** the authorizer callback may be passed.
2877 ** These action code values signify what kind of operation is to be
2878 ** authorized. The 3rd and 4th parameters to the authorization
2879 ** callback function will be parameters or NULL depending on which of these
2880 ** codes is used as the second parameter. ^(The 5th parameter to the
2881 ** authorizer callback is the name of the database ("main", "temp",
2882 ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
2883 ** is the name of the inner-most trigger or view that is responsible for
2884 ** the access attempt or NULL if this access attempt is directly from
2885 ** top-level SQL code.
2887 /******************************************* 3rd ************ 4th ***********/
2888 #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
2889 #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
2890 #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
2891 #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
2892 #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
2893 #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
2894 #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
2895 #define SQLITE_CREATE_VIEW 8 /* View Name NULL */
2896 #define SQLITE_DELETE 9 /* Table Name NULL */
2897 #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
2898 #define SQLITE_DROP_TABLE 11 /* Table Name NULL */
2899 #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
2900 #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
2901 #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
2902 #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
2903 #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
2904 #define SQLITE_DROP_VIEW 17 /* View Name NULL */
2905 #define SQLITE_INSERT 18 /* Table Name NULL */
2906 #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
2907 #define SQLITE_READ 20 /* Table Name Column Name */
2908 #define SQLITE_SELECT 21 /* NULL NULL */
2909 #define SQLITE_TRANSACTION 22 /* Operation NULL */
2910 #define SQLITE_UPDATE 23 /* Table Name Column Name */
2911 #define SQLITE_ATTACH 24 /* Filename NULL */
2912 #define SQLITE_DETACH 25 /* Database Name NULL */
2913 #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
2914 #define SQLITE_REINDEX 27 /* Index Name NULL */
2915 #define SQLITE_ANALYZE 28 /* Table Name NULL */
2916 #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
2917 #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
2918 #define SQLITE_FUNCTION 31 /* NULL Function Name */
2919 #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
2920 #define SQLITE_COPY 0 /* No longer used */
2921 #define SQLITE_RECURSIVE 33 /* NULL NULL */
2924 ** CAPI3REF: Tracing And Profiling Functions
2927 ** These routines register callback functions that can be used for
2928 ** tracing and profiling the execution of SQL statements.
2930 ** ^The callback function registered by sqlite3_trace() is invoked at
2931 ** various times when an SQL statement is being run by [sqlite3_step()].
2932 ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
2933 ** SQL statement text as the statement first begins executing.
2934 ** ^(Additional sqlite3_trace() callbacks might occur
2935 ** as each triggered subprogram is entered. The callbacks for triggers
2936 ** contain a UTF-8 SQL comment that identifies the trigger.)^
2938 ** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
2939 ** the length of [bound parameter] expansion in the output of sqlite3_trace().
2941 ** ^The callback function registered by sqlite3_profile() is invoked
2942 ** as each SQL statement finishes. ^The profile callback contains
2943 ** the original statement text and an estimate of wall-clock time
2944 ** of how long that statement took to run. ^The profile callback
2945 ** time is in units of nanoseconds, however the current implementation
2946 ** is only capable of millisecond resolution so the six least significant
2947 ** digits in the time are meaningless. Future versions of SQLite
2948 ** might provide greater resolution on the profiler callback. The
2949 ** sqlite3_profile() function is considered experimental and is
2950 ** subject to change in future versions of SQLite.
2952 SQLITE_API void *SQLITE_STDCALL sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
2953 SQLITE_API SQLITE_EXPERIMENTAL void *SQLITE_STDCALL sqlite3_profile(sqlite3*,
2954 void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
2957 ** CAPI3REF: Query Progress Callbacks
2960 ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
2961 ** function X to be invoked periodically during long running calls to
2962 ** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
2963 ** database connection D. An example use for this
2964 ** interface is to keep a GUI updated during a large query.
2966 ** ^The parameter P is passed through as the only parameter to the
2967 ** callback function X. ^The parameter N is the approximate number of
2968 ** [virtual machine instructions] that are evaluated between successive
2969 ** invocations of the callback X. ^If N is less than one then the progress
2970 ** handler is disabled.
2972 ** ^Only a single progress handler may be defined at one time per
2973 ** [database connection]; setting a new progress handler cancels the
2974 ** old one. ^Setting parameter X to NULL disables the progress handler.
2975 ** ^The progress handler is also disabled by setting N to a value less
2978 ** ^If the progress callback returns non-zero, the operation is
2979 ** interrupted. This feature can be used to implement a
2980 ** "Cancel" button on a GUI progress dialog box.
2982 ** The progress handler callback must not do anything that will modify
2983 ** the database connection that invoked the progress handler.
2984 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2985 ** database connections for the meaning of "modify" in this paragraph.
2988 SQLITE_API void SQLITE_STDCALL sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
2991 ** CAPI3REF: Opening A New Database Connection
2992 ** CONSTRUCTOR: sqlite3
2994 ** ^These routines open an SQLite database file as specified by the
2995 ** filename argument. ^The filename argument is interpreted as UTF-8 for
2996 ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
2997 ** order for sqlite3_open16(). ^(A [database connection] handle is usually
2998 ** returned in *ppDb, even if an error occurs. The only exception is that
2999 ** if SQLite is unable to allocate memory to hold the [sqlite3] object,
3000 ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
3001 ** object.)^ ^(If the database is opened (and/or created) successfully, then
3002 ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
3003 ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
3004 ** an English language description of the error following a failure of any
3005 ** of the sqlite3_open() routines.
3007 ** ^The default encoding will be UTF-8 for databases created using
3008 ** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases
3009 ** created using sqlite3_open16() will be UTF-16 in the native byte order.
3011 ** Whether or not an error occurs when it is opened, resources
3012 ** associated with the [database connection] handle should be released by
3013 ** passing it to [sqlite3_close()] when it is no longer required.
3015 ** The sqlite3_open_v2() interface works like sqlite3_open()
3016 ** except that it accepts two additional parameters for additional control
3017 ** over the new database connection. ^(The flags parameter to
3018 ** sqlite3_open_v2() can take one of
3019 ** the following three values, optionally combined with the
3020 ** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
3021 ** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^
3024 ** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
3025 ** <dd>The database is opened in read-only mode. If the database does not
3026 ** already exist, an error is returned.</dd>)^
3028 ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
3029 ** <dd>The database is opened for reading and writing if possible, or reading
3030 ** only if the file is write protected by the operating system. In either
3031 ** case the database must already exist, otherwise an error is returned.</dd>)^
3033 ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
3034 ** <dd>The database is opened for reading and writing, and is created if
3035 ** it does not already exist. This is the behavior that is always used for
3036 ** sqlite3_open() and sqlite3_open16().</dd>)^
3039 ** If the 3rd parameter to sqlite3_open_v2() is not one of the
3040 ** combinations shown above optionally combined with other
3041 ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
3042 ** then the behavior is undefined.
3044 ** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
3045 ** opens in the multi-thread [threading mode] as long as the single-thread
3046 ** mode has not been set at compile-time or start-time. ^If the
3047 ** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
3048 ** in the serialized [threading mode] unless single-thread was
3049 ** previously selected at compile-time or start-time.
3050 ** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
3051 ** eligible to use [shared cache mode], regardless of whether or not shared
3052 ** cache is enabled using [sqlite3_enable_shared_cache()]. ^The
3053 ** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
3054 ** participate in [shared cache mode] even if it is enabled.
3056 ** ^The fourth parameter to sqlite3_open_v2() is the name of the
3057 ** [sqlite3_vfs] object that defines the operating system interface that
3058 ** the new database connection should use. ^If the fourth parameter is
3059 ** a NULL pointer then the default [sqlite3_vfs] object is used.
3061 ** ^If the filename is ":memory:", then a private, temporary in-memory database
3062 ** is created for the connection. ^This in-memory database will vanish when
3063 ** the database connection is closed. Future versions of SQLite might
3064 ** make use of additional special filenames that begin with the ":" character.
3065 ** It is recommended that when a database filename actually does begin with
3066 ** a ":" character you should prefix the filename with a pathname such as
3067 ** "./" to avoid ambiguity.
3069 ** ^If the filename is an empty string, then a private, temporary
3070 ** on-disk database will be created. ^This private database will be
3071 ** automatically deleted as soon as the database connection is closed.
3073 ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
3075 ** ^If [URI filename] interpretation is enabled, and the filename argument
3076 ** begins with "file:", then the filename is interpreted as a URI. ^URI
3077 ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
3078 ** set in the fourth argument to sqlite3_open_v2(), or if it has
3079 ** been enabled globally using the [SQLITE_CONFIG_URI] option with the
3080 ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
3081 ** As of SQLite version 3.7.7, URI filename interpretation is turned off
3082 ** by default, but future releases of SQLite might enable URI filename
3083 ** interpretation by default. See "[URI filenames]" for additional
3086 ** URI filenames are parsed according to RFC 3986. ^If the URI contains an
3087 ** authority, then it must be either an empty string or the string
3088 ** "localhost". ^If the authority is not an empty string or "localhost", an
3089 ** error is returned to the caller. ^The fragment component of a URI, if
3090 ** present, is ignored.
3092 ** ^SQLite uses the path component of the URI as the name of the disk file
3093 ** which contains the database. ^If the path begins with a '/' character,
3094 ** then it is interpreted as an absolute path. ^If the path does not begin
3095 ** with a '/' (meaning that the authority section is omitted from the URI)
3096 ** then the path is interpreted as a relative path.
3097 ** ^(On windows, the first component of an absolute path
3098 ** is a drive specification (e.g. "C:").)^
3100 ** [[core URI query parameters]]
3101 ** The query component of a URI may contain parameters that are interpreted
3102 ** either by SQLite itself, or by a [VFS | custom VFS implementation].
3103 ** SQLite and its built-in [VFSes] interpret the
3104 ** following query parameters:
3107 ** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
3108 ** a VFS object that provides the operating system interface that should
3109 ** be used to access the database file on disk. ^If this option is set to
3110 ** an empty string the default VFS object is used. ^Specifying an unknown
3111 ** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
3112 ** present, then the VFS specified by the option takes precedence over
3113 ** the value passed as the fourth parameter to sqlite3_open_v2().
3115 ** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
3116 ** "rwc", or "memory". Attempting to set it to any other value is
3118 ** ^If "ro" is specified, then the database is opened for read-only
3119 ** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
3120 ** third argument to sqlite3_open_v2(). ^If the mode option is set to
3121 ** "rw", then the database is opened for read-write (but not create)
3122 ** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
3123 ** been set. ^Value "rwc" is equivalent to setting both
3124 ** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is
3125 ** set to "memory" then a pure [in-memory database] that never reads
3126 ** or writes from disk is used. ^It is an error to specify a value for
3127 ** the mode parameter that is less restrictive than that specified by
3128 ** the flags passed in the third parameter to sqlite3_open_v2().
3130 ** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
3131 ** "private". ^Setting it to "shared" is equivalent to setting the
3132 ** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
3133 ** sqlite3_open_v2(). ^Setting the cache parameter to "private" is
3134 ** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
3135 ** ^If sqlite3_open_v2() is used and the "cache" parameter is present in
3136 ** a URI filename, its value overrides any behavior requested by setting
3137 ** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
3139 ** <li> <b>psow</b>: ^The psow parameter indicates whether or not the
3140 ** [powersafe overwrite] property does or does not apply to the
3141 ** storage media on which the database file resides.
3143 ** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
3144 ** which if set disables file locking in rollback journal modes. This
3145 ** is useful for accessing a database on a filesystem that does not
3146 ** support locking. Caution: Database corruption might result if two
3147 ** or more processes write to the same database and any one of those
3148 ** processes uses nolock=1.
3150 ** <li> <b>immutable</b>: ^The immutable parameter is a boolean query
3151 ** parameter that indicates that the database file is stored on
3152 ** read-only media. ^When immutable is set, SQLite assumes that the
3153 ** database file cannot be changed, even by a process with higher
3154 ** privilege, and so the database is opened read-only and all locking
3155 ** and change detection is disabled. Caution: Setting the immutable
3156 ** property on a database file that does in fact change can result
3157 ** in incorrect query results and/or [SQLITE_CORRUPT] errors.
3158 ** See also: [SQLITE_IOCAP_IMMUTABLE].
3162 ** ^Specifying an unknown parameter in the query component of a URI is not an
3163 ** error. Future versions of SQLite might understand additional query
3164 ** parameters. See "[query parameters with special meaning to SQLite]" for
3165 ** additional information.
3167 ** [[URI filename examples]] <h3>URI filename examples</h3>
3169 ** <table border="1" align=center cellpadding=5>
3170 ** <tr><th> URI filenames <th> Results
3171 ** <tr><td> file:data.db <td>
3172 ** Open the file "data.db" in the current directory.
3173 ** <tr><td> file:/home/fred/data.db<br>
3174 ** file:///home/fred/data.db <br>
3175 ** file://localhost/home/fred/data.db <br> <td>
3176 ** Open the database file "/home/fred/data.db".
3177 ** <tr><td> file://darkstar/home/fred/data.db <td>
3178 ** An error. "darkstar" is not a recognized authority.
3179 ** <tr><td style="white-space:nowrap">
3180 ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
3181 ** <td> Windows only: Open the file "data.db" on fred's desktop on drive
3182 ** C:. Note that the %20 escaping in this example is not strictly
3183 ** necessary - space characters can be used literally
3184 ** in URI filenames.
3185 ** <tr><td> file:data.db?mode=ro&cache=private <td>
3186 ** Open file "data.db" in the current directory for read-only access.
3187 ** Regardless of whether or not shared-cache mode is enabled by
3188 ** default, use a private cache.
3189 ** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
3190 ** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
3191 ** that uses dot-files in place of posix advisory locking.
3192 ** <tr><td> file:data.db?mode=readonly <td>
3193 ** An error. "readonly" is not a valid option for the "mode" parameter.
3196 ** ^URI hexadecimal escape sequences (%HH) are supported within the path and
3197 ** query components of a URI. A hexadecimal escape sequence consists of a
3198 ** percent sign - "%" - followed by exactly two hexadecimal digits
3199 ** specifying an octet value. ^Before the path or query components of a
3200 ** URI filename are interpreted, they are encoded using UTF-8 and all
3201 ** hexadecimal escape sequences replaced by a single byte containing the
3202 ** corresponding octet. If this process generates an invalid UTF-8 encoding,
3203 ** the results are undefined.
3205 ** <b>Note to Windows users:</b> The encoding used for the filename argument
3206 ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
3207 ** codepage is currently defined. Filenames containing international
3208 ** characters must be converted to UTF-8 prior to passing them into
3209 ** sqlite3_open() or sqlite3_open_v2().
3211 ** <b>Note to Windows Runtime users:</b> The temporary directory must be set
3212 ** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various
3213 ** features that require the use of temporary files may fail.
3215 ** See also: [sqlite3_temp_directory]
3217 SQLITE_API int SQLITE_STDCALL sqlite3_open(
3218 const char *filename, /* Database filename (UTF-8) */
3219 sqlite3 **ppDb /* OUT: SQLite db handle */
3221 SQLITE_API int SQLITE_STDCALL sqlite3_open16(
3222 const void *filename, /* Database filename (UTF-16) */
3223 sqlite3 **ppDb /* OUT: SQLite db handle */
3225 SQLITE_API int SQLITE_STDCALL sqlite3_open_v2(
3226 const char *filename, /* Database filename (UTF-8) */
3227 sqlite3 **ppDb, /* OUT: SQLite db handle */
3228 int flags, /* Flags */
3229 const char *zVfs /* Name of VFS module to use */
3233 ** CAPI3REF: Obtain Values For URI Parameters
3235 ** These are utility routines, useful to VFS implementations, that check
3236 ** to see if a database file was a URI that contained a specific query
3237 ** parameter, and if so obtains the value of that query parameter.
3239 ** If F is the database filename pointer passed into the xOpen() method of
3240 ** a VFS implementation when the flags parameter to xOpen() has one or
3241 ** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
3242 ** P is the name of the query parameter, then
3243 ** sqlite3_uri_parameter(F,P) returns the value of the P
3244 ** parameter if it exists or a NULL pointer if P does not appear as a
3245 ** query parameter on F. If P is a query parameter of F
3246 ** has no explicit value, then sqlite3_uri_parameter(F,P) returns
3247 ** a pointer to an empty string.
3249 ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
3250 ** parameter and returns true (1) or false (0) according to the value
3251 ** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
3252 ** value of query parameter P is one of "yes", "true", or "on" in any
3253 ** case or if the value begins with a non-zero number. The
3254 ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
3255 ** query parameter P is one of "no", "false", or "off" in any case or
3256 ** if the value begins with a numeric zero. If P is not a query
3257 ** parameter on F or if the value of P is does not match any of the
3258 ** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
3260 ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
3261 ** 64-bit signed integer and returns that integer, or D if P does not
3262 ** exist. If the value of P is something other than an integer, then
3263 ** zero is returned.
3265 ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
3266 ** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and
3267 ** is not a database file pathname pointer that SQLite passed into the xOpen
3268 ** VFS method, then the behavior of this routine is undefined and probably
3271 SQLITE_API const char *SQLITE_STDCALL sqlite3_uri_parameter(const char *zFilename, const char *zParam);
3272 SQLITE_API int SQLITE_STDCALL sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
3273 SQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
3277 ** CAPI3REF: Error Codes And Messages
3280 ** ^If the most recent sqlite3_* API call associated with
3281 ** [database connection] D failed, then the sqlite3_errcode(D) interface
3282 ** returns the numeric [result code] or [extended result code] for that
3284 ** If the most recent API call was successful,
3285 ** then the return value from sqlite3_errcode() is undefined.
3286 ** ^The sqlite3_extended_errcode()
3287 ** interface is the same except that it always returns the
3288 ** [extended result code] even when extended result codes are
3291 ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
3292 ** text that describes the error, as either UTF-8 or UTF-16 respectively.
3293 ** ^(Memory to hold the error message string is managed internally.
3294 ** The application does not need to worry about freeing the result.
3295 ** However, the error string might be overwritten or deallocated by
3296 ** subsequent calls to other SQLite interface functions.)^
3298 ** ^The sqlite3_errstr() interface returns the English-language text
3299 ** that describes the [result code], as UTF-8.
3300 ** ^(Memory to hold the error message string is managed internally
3301 ** and must not be freed by the application)^.
3303 ** When the serialized [threading mode] is in use, it might be the
3304 ** case that a second error occurs on a separate thread in between
3305 ** the time of the first error and the call to these interfaces.
3306 ** When that happens, the second error will be reported since these
3307 ** interfaces always report the most recent result. To avoid
3308 ** this, each thread can obtain exclusive use of the [database connection] D
3309 ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
3310 ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
3311 ** all calls to the interfaces listed here are completed.
3313 ** If an interface fails with SQLITE_MISUSE, that means the interface
3314 ** was invoked incorrectly by the application. In that case, the
3315 ** error code and message may or may not be set.
3317 SQLITE_API int SQLITE_STDCALL sqlite3_errcode(sqlite3 *db);
3318 SQLITE_API int SQLITE_STDCALL sqlite3_extended_errcode(sqlite3 *db);
3319 SQLITE_API const char *SQLITE_STDCALL sqlite3_errmsg(sqlite3*);
3320 SQLITE_API const void *SQLITE_STDCALL sqlite3_errmsg16(sqlite3*);
3321 SQLITE_API const char *SQLITE_STDCALL sqlite3_errstr(int);
3324 ** CAPI3REF: Prepared Statement Object
3325 ** KEYWORDS: {prepared statement} {prepared statements}
3327 ** An instance of this object represents a single SQL statement that
3328 ** has been compiled into binary form and is ready to be evaluated.
3330 ** Think of each SQL statement as a separate computer program. The
3331 ** original SQL text is source code. A prepared statement object
3332 ** is the compiled object code. All SQL must be converted into a
3333 ** prepared statement before it can be run.
3335 ** The life-cycle of a prepared statement object usually goes like this:
3338 ** <li> Create the prepared statement object using [sqlite3_prepare_v2()].
3339 ** <li> Bind values to [parameters] using the sqlite3_bind_*()
3341 ** <li> Run the SQL by calling [sqlite3_step()] one or more times.
3342 ** <li> Reset the prepared statement using [sqlite3_reset()] then go back
3343 ** to step 2. Do this zero or more times.
3344 ** <li> Destroy the object using [sqlite3_finalize()].
3347 typedef struct sqlite3_stmt sqlite3_stmt;
3350 ** CAPI3REF: Run-time Limits
3353 ** ^(This interface allows the size of various constructs to be limited
3354 ** on a connection by connection basis. The first parameter is the
3355 ** [database connection] whose limit is to be set or queried. The
3356 ** second parameter is one of the [limit categories] that define a
3357 ** class of constructs to be size limited. The third parameter is the
3358 ** new limit for that construct.)^
3360 ** ^If the new limit is a negative number, the limit is unchanged.
3361 ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
3362 ** [limits | hard upper bound]
3363 ** set at compile-time by a C preprocessor macro called
3364 ** [limits | SQLITE_MAX_<i>NAME</i>].
3365 ** (The "_LIMIT_" in the name is changed to "_MAX_".))^
3366 ** ^Attempts to increase a limit above its hard upper bound are
3367 ** silently truncated to the hard upper bound.
3369 ** ^Regardless of whether or not the limit was changed, the
3370 ** [sqlite3_limit()] interface returns the prior value of the limit.
3371 ** ^Hence, to find the current value of a limit without changing it,
3372 ** simply invoke this interface with the third parameter set to -1.
3374 ** Run-time limits are intended for use in applications that manage
3375 ** both their own internal database and also databases that are controlled
3376 ** by untrusted external sources. An example application might be a
3377 ** web browser that has its own databases for storing history and
3378 ** separate databases controlled by JavaScript applications downloaded
3379 ** off the Internet. The internal databases can be given the
3380 ** large, default limits. Databases managed by external sources can
3381 ** be given much smaller limits designed to prevent a denial of service
3382 ** attack. Developers might also want to use the [sqlite3_set_authorizer()]
3383 ** interface to further control untrusted SQL. The size of the database
3384 ** created by an untrusted script can be contained using the
3385 ** [max_page_count] [PRAGMA].
3387 ** New run-time limit categories may be added in future releases.
3389 SQLITE_API int SQLITE_STDCALL sqlite3_limit(sqlite3*, int id, int newVal);
3392 ** CAPI3REF: Run-Time Limit Categories
3393 ** KEYWORDS: {limit category} {*limit categories}
3395 ** These constants define various performance limits
3396 ** that can be lowered at run-time using [sqlite3_limit()].
3397 ** The synopsis of the meanings of the various limits is shown below.
3398 ** Additional information is available at [limits | Limits in SQLite].
3401 ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
3402 ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
3404 ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
3405 ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
3407 ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
3408 ** <dd>The maximum number of columns in a table definition or in the
3409 ** result set of a [SELECT] or the maximum number of columns in an index
3410 ** or in an ORDER BY or GROUP BY clause.</dd>)^
3412 ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
3413 ** <dd>The maximum depth of the parse tree on any expression.</dd>)^
3415 ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
3416 ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
3418 ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
3419 ** <dd>The maximum number of instructions in a virtual machine program
3420 ** used to implement an SQL statement. This limit is not currently
3421 ** enforced, though that might be added in some future release of
3424 ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
3425 ** <dd>The maximum number of arguments on a function.</dd>)^
3427 ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
3428 ** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
3430 ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
3431 ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
3432 ** <dd>The maximum length of the pattern argument to the [LIKE] or
3433 ** [GLOB] operators.</dd>)^
3435 ** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
3436 ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
3437 ** <dd>The maximum index number of any [parameter] in an SQL statement.)^
3439 ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
3440 ** <dd>The maximum depth of recursion for triggers.</dd>)^
3442 ** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>
3443 ** <dd>The maximum number of auxiliary worker threads that a single
3444 ** [prepared statement] may start.</dd>)^
3447 #define SQLITE_LIMIT_LENGTH 0
3448 #define SQLITE_LIMIT_SQL_LENGTH 1
3449 #define SQLITE_LIMIT_COLUMN 2
3450 #define SQLITE_LIMIT_EXPR_DEPTH 3
3451 #define SQLITE_LIMIT_COMPOUND_SELECT 4
3452 #define SQLITE_LIMIT_VDBE_OP 5
3453 #define SQLITE_LIMIT_FUNCTION_ARG 6
3454 #define SQLITE_LIMIT_ATTACHED 7
3455 #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
3456 #define SQLITE_LIMIT_VARIABLE_NUMBER 9
3457 #define SQLITE_LIMIT_TRIGGER_DEPTH 10
3458 #define SQLITE_LIMIT_WORKER_THREADS 11
3461 ** CAPI3REF: Compiling An SQL Statement
3462 ** KEYWORDS: {SQL statement compiler}
3464 ** CONSTRUCTOR: sqlite3_stmt
3466 ** To execute an SQL query, it must first be compiled into a byte-code
3467 ** program using one of these routines.
3469 ** The first argument, "db", is a [database connection] obtained from a
3470 ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
3471 ** [sqlite3_open16()]. The database connection must not have been closed.
3473 ** The second argument, "zSql", is the statement to be compiled, encoded
3474 ** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
3475 ** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
3478 ** ^If the nByte argument is negative, then zSql is read up to the
3479 ** first zero terminator. ^If nByte is positive, then it is the
3480 ** number of bytes read from zSql. ^If nByte is zero, then no prepared
3481 ** statement is generated.
3482 ** If the caller knows that the supplied string is nul-terminated, then
3483 ** there is a small performance advantage to passing an nByte parameter that
3484 ** is the number of bytes in the input string <i>including</i>
3485 ** the nul-terminator.
3487 ** ^If pzTail is not NULL then *pzTail is made to point to the first byte
3488 ** past the end of the first SQL statement in zSql. These routines only
3489 ** compile the first statement in zSql, so *pzTail is left pointing to
3490 ** what remains uncompiled.
3492 ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
3493 ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
3494 ** to NULL. ^If the input text contains no SQL (if the input is an empty
3495 ** string or a comment) then *ppStmt is set to NULL.
3496 ** The calling procedure is responsible for deleting the compiled
3497 ** SQL statement using [sqlite3_finalize()] after it has finished with it.
3498 ** ppStmt may not be NULL.
3500 ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
3501 ** otherwise an [error code] is returned.
3503 ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
3504 ** recommended for all new programs. The two older interfaces are retained
3505 ** for backwards compatibility, but their use is discouraged.
3506 ** ^In the "v2" interfaces, the prepared statement
3507 ** that is returned (the [sqlite3_stmt] object) contains a copy of the
3508 ** original SQL text. This causes the [sqlite3_step()] interface to
3509 ** behave differently in three ways:
3513 ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
3514 ** always used to do, [sqlite3_step()] will automatically recompile the SQL
3515 ** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
3516 ** retries will occur before sqlite3_step() gives up and returns an error.
3520 ** ^When an error occurs, [sqlite3_step()] will return one of the detailed
3521 ** [error codes] or [extended error codes]. ^The legacy behavior was that
3522 ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
3523 ** and the application would have to make a second call to [sqlite3_reset()]
3524 ** in order to find the underlying cause of the problem. With the "v2" prepare
3525 ** interfaces, the underlying reason for the error is returned immediately.
3529 ** ^If the specific value bound to [parameter | host parameter] in the
3530 ** WHERE clause might influence the choice of query plan for a statement,
3531 ** then the statement will be automatically recompiled, as if there had been
3532 ** a schema change, on the first [sqlite3_step()] call following any change
3533 ** to the [sqlite3_bind_text | bindings] of that [parameter].
3534 ** ^The specific value of WHERE-clause [parameter] might influence the
3535 ** choice of query plan if the parameter is the left-hand side of a [LIKE]
3536 ** or [GLOB] operator or if the parameter is compared to an indexed column
3537 ** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
3541 SQLITE_API int SQLITE_STDCALL sqlite3_prepare(
3542 sqlite3 *db, /* Database handle */
3543 const char *zSql, /* SQL statement, UTF-8 encoded */
3544 int nByte, /* Maximum length of zSql in bytes. */
3545 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
3546 const char **pzTail /* OUT: Pointer to unused portion of zSql */
3548 SQLITE_API int SQLITE_STDCALL sqlite3_prepare_v2(
3549 sqlite3 *db, /* Database handle */
3550 const char *zSql, /* SQL statement, UTF-8 encoded */
3551 int nByte, /* Maximum length of zSql in bytes. */
3552 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
3553 const char **pzTail /* OUT: Pointer to unused portion of zSql */
3555 SQLITE_API int SQLITE_STDCALL sqlite3_prepare16(
3556 sqlite3 *db, /* Database handle */
3557 const void *zSql, /* SQL statement, UTF-16 encoded */
3558 int nByte, /* Maximum length of zSql in bytes. */
3559 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
3560 const void **pzTail /* OUT: Pointer to unused portion of zSql */
3562 SQLITE_API int SQLITE_STDCALL sqlite3_prepare16_v2(
3563 sqlite3 *db, /* Database handle */
3564 const void *zSql, /* SQL statement, UTF-16 encoded */
3565 int nByte, /* Maximum length of zSql in bytes. */
3566 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
3567 const void **pzTail /* OUT: Pointer to unused portion of zSql */
3571 ** CAPI3REF: Retrieving Statement SQL
3572 ** METHOD: sqlite3_stmt
3574 ** ^This interface can be used to retrieve a saved copy of the original
3575 ** SQL text used to create a [prepared statement] if that statement was
3576 ** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
3578 SQLITE_API const char *SQLITE_STDCALL sqlite3_sql(sqlite3_stmt *pStmt);
3581 ** CAPI3REF: Determine If An SQL Statement Writes The Database
3582 ** METHOD: sqlite3_stmt
3584 ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
3585 ** and only if the [prepared statement] X makes no direct changes to
3586 ** the content of the database file.
3588 ** Note that [application-defined SQL functions] or
3589 ** [virtual tables] might change the database indirectly as a side effect.
3590 ** ^(For example, if an application defines a function "eval()" that
3591 ** calls [sqlite3_exec()], then the following SQL statement would
3592 ** change the database file through side-effects:
3594 ** <blockquote><pre>
3595 ** SELECT eval('DELETE FROM t1') FROM t2;
3596 ** </pre></blockquote>
3598 ** But because the [SELECT] statement does not change the database file
3599 ** directly, sqlite3_stmt_readonly() would still return true.)^
3601 ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
3602 ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
3603 ** since the statements themselves do not actually modify the database but
3604 ** rather they control the timing of when other statements modify the
3605 ** database. ^The [ATTACH] and [DETACH] statements also cause
3606 ** sqlite3_stmt_readonly() to return true since, while those statements
3607 ** change the configuration of a database connection, they do not make
3608 ** changes to the content of the database files on disk.
3610 SQLITE_API int SQLITE_STDCALL sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
3613 ** CAPI3REF: Determine If A Prepared Statement Has Been Reset
3614 ** METHOD: sqlite3_stmt
3616 ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
3617 ** [prepared statement] S has been stepped at least once using
3618 ** [sqlite3_step(S)] but has neither run to completion (returned
3619 ** [SQLITE_DONE] from [sqlite3_step(S)]) nor
3620 ** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S)
3621 ** interface returns false if S is a NULL pointer. If S is not a
3622 ** NULL pointer and is not a pointer to a valid [prepared statement]
3623 ** object, then the behavior is undefined and probably undesirable.
3625 ** This interface can be used in combination [sqlite3_next_stmt()]
3626 ** to locate all prepared statements associated with a database
3627 ** connection that are in need of being reset. This can be used,
3628 ** for example, in diagnostic routines to search for prepared
3629 ** statements that are holding a transaction open.
3631 SQLITE_API int SQLITE_STDCALL sqlite3_stmt_busy(sqlite3_stmt*);
3634 ** CAPI3REF: Dynamically Typed Value Object
3635 ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
3637 ** SQLite uses the sqlite3_value object to represent all values
3638 ** that can be stored in a database table. SQLite uses dynamic typing
3639 ** for the values it stores. ^Values stored in sqlite3_value objects
3640 ** can be integers, floating point values, strings, BLOBs, or NULL.
3642 ** An sqlite3_value object may be either "protected" or "unprotected".
3643 ** Some interfaces require a protected sqlite3_value. Other interfaces
3644 ** will accept either a protected or an unprotected sqlite3_value.
3645 ** Every interface that accepts sqlite3_value arguments specifies
3646 ** whether or not it requires a protected sqlite3_value. The
3647 ** [sqlite3_value_dup()] interface can be used to construct a new
3648 ** protected sqlite3_value from an unprotected sqlite3_value.
3650 ** The terms "protected" and "unprotected" refer to whether or not
3651 ** a mutex is held. An internal mutex is held for a protected
3652 ** sqlite3_value object but no mutex is held for an unprotected
3653 ** sqlite3_value object. If SQLite is compiled to be single-threaded
3654 ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
3655 ** or if SQLite is run in one of reduced mutex modes
3656 ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
3657 ** then there is no distinction between protected and unprotected
3658 ** sqlite3_value objects and they can be used interchangeably. However,
3659 ** for maximum code portability it is recommended that applications
3660 ** still make the distinction between protected and unprotected
3661 ** sqlite3_value objects even when not strictly required.
3663 ** ^The sqlite3_value objects that are passed as parameters into the
3664 ** implementation of [application-defined SQL functions] are protected.
3665 ** ^The sqlite3_value object returned by
3666 ** [sqlite3_column_value()] is unprotected.
3667 ** Unprotected sqlite3_value objects may only be used with
3668 ** [sqlite3_result_value()] and [sqlite3_bind_value()].
3669 ** The [sqlite3_value_blob | sqlite3_value_type()] family of
3670 ** interfaces require protected sqlite3_value objects.
3672 typedef struct Mem sqlite3_value;
3675 ** CAPI3REF: SQL Function Context Object
3677 ** The context in which an SQL function executes is stored in an
3678 ** sqlite3_context object. ^A pointer to an sqlite3_context object
3679 ** is always first parameter to [application-defined SQL functions].
3680 ** The application-defined SQL function implementation will pass this
3681 ** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
3682 ** [sqlite3_aggregate_context()], [sqlite3_user_data()],
3683 ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
3684 ** and/or [sqlite3_set_auxdata()].
3686 typedef struct sqlite3_context sqlite3_context;
3689 ** CAPI3REF: Binding Values To Prepared Statements
3690 ** KEYWORDS: {host parameter} {host parameters} {host parameter name}
3691 ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
3692 ** METHOD: sqlite3_stmt
3694 ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
3695 ** literals may be replaced by a [parameter] that matches one of following
3706 ** In the templates above, NNN represents an integer literal,
3707 ** and VVV represents an alphanumeric identifier.)^ ^The values of these
3708 ** parameters (also called "host parameter names" or "SQL parameters")
3709 ** can be set using the sqlite3_bind_*() routines defined here.
3711 ** ^The first argument to the sqlite3_bind_*() routines is always
3712 ** a pointer to the [sqlite3_stmt] object returned from
3713 ** [sqlite3_prepare_v2()] or its variants.
3715 ** ^The second argument is the index of the SQL parameter to be set.
3716 ** ^The leftmost SQL parameter has an index of 1. ^When the same named
3717 ** SQL parameter is used more than once, second and subsequent
3718 ** occurrences have the same index as the first occurrence.
3719 ** ^The index for named parameters can be looked up using the
3720 ** [sqlite3_bind_parameter_index()] API if desired. ^The index
3721 ** for "?NNN" parameters is the value of NNN.
3722 ** ^The NNN value must be between 1 and the [sqlite3_limit()]
3723 ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
3725 ** ^The third argument is the value to bind to the parameter.
3726 ** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
3727 ** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
3728 ** is ignored and the end result is the same as sqlite3_bind_null().
3730 ** ^(In those routines that have a fourth argument, its value is the
3731 ** number of bytes in the parameter. To be clear: the value is the
3732 ** number of <u>bytes</u> in the value, not the number of characters.)^
3733 ** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
3734 ** is negative, then the length of the string is
3735 ** the number of bytes up to the first zero terminator.
3736 ** If the fourth parameter to sqlite3_bind_blob() is negative, then
3737 ** the behavior is undefined.
3738 ** If a non-negative fourth parameter is provided to sqlite3_bind_text()
3739 ** or sqlite3_bind_text16() or sqlite3_bind_text64() then
3740 ** that parameter must be the byte offset
3741 ** where the NUL terminator would occur assuming the string were NUL
3742 ** terminated. If any NUL characters occur at byte offsets less than
3743 ** the value of the fourth parameter then the resulting string value will
3744 ** contain embedded NULs. The result of expressions involving strings
3745 ** with embedded NULs is undefined.
3747 ** ^The fifth argument to the BLOB and string binding interfaces
3748 ** is a destructor used to dispose of the BLOB or
3749 ** string after SQLite has finished with it. ^The destructor is called
3750 ** to dispose of the BLOB or string even if the call to bind API fails.
3751 ** ^If the fifth argument is
3752 ** the special value [SQLITE_STATIC], then SQLite assumes that the
3753 ** information is in static, unmanaged space and does not need to be freed.
3754 ** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
3755 ** SQLite makes its own private copy of the data immediately, before
3756 ** the sqlite3_bind_*() routine returns.
3758 ** ^The sixth argument to sqlite3_bind_text64() must be one of
3759 ** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
3760 ** to specify the encoding of the text in the third parameter. If
3761 ** the sixth argument to sqlite3_bind_text64() is not one of the
3762 ** allowed values shown above, or if the text encoding is different
3763 ** from the encoding specified by the sixth parameter, then the behavior
3766 ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
3767 ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
3768 ** (just an integer to hold its size) while it is being processed.
3769 ** Zeroblobs are intended to serve as placeholders for BLOBs whose
3770 ** content is later written using
3771 ** [sqlite3_blob_open | incremental BLOB I/O] routines.
3772 ** ^A negative value for the zeroblob results in a zero-length BLOB.
3774 ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
3775 ** for the [prepared statement] or with a prepared statement for which
3776 ** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
3777 ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
3778 ** routine is passed a [prepared statement] that has been finalized, the
3779 ** result is undefined and probably harmful.
3781 ** ^Bindings are not cleared by the [sqlite3_reset()] routine.
3782 ** ^Unbound parameters are interpreted as NULL.
3784 ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
3785 ** [error code] if anything goes wrong.
3786 ** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
3787 ** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
3788 ** [SQLITE_MAX_LENGTH].
3789 ** ^[SQLITE_RANGE] is returned if the parameter
3790 ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
3792 ** See also: [sqlite3_bind_parameter_count()],
3793 ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
3795 SQLITE_API int SQLITE_STDCALL sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
3796 SQLITE_API int SQLITE_STDCALL sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64,
3798 SQLITE_API int SQLITE_STDCALL sqlite3_bind_double(sqlite3_stmt*, int, double);
3799 SQLITE_API int SQLITE_STDCALL sqlite3_bind_int(sqlite3_stmt*, int, int);
3800 SQLITE_API int SQLITE_STDCALL sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
3801 SQLITE_API int SQLITE_STDCALL sqlite3_bind_null(sqlite3_stmt*, int);
3802 SQLITE_API int SQLITE_STDCALL sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*));
3803 SQLITE_API int SQLITE_STDCALL sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
3804 SQLITE_API int SQLITE_STDCALL sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64,
3805 void(*)(void*), unsigned char encoding);
3806 SQLITE_API int SQLITE_STDCALL sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
3807 SQLITE_API int SQLITE_STDCALL sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
3808 SQLITE_API int SQLITE_STDCALL sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64);
3811 ** CAPI3REF: Number Of SQL Parameters
3812 ** METHOD: sqlite3_stmt
3814 ** ^This routine can be used to find the number of [SQL parameters]
3815 ** in a [prepared statement]. SQL parameters are tokens of the
3816 ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
3817 ** placeholders for values that are [sqlite3_bind_blob | bound]
3818 ** to the parameters at a later time.
3820 ** ^(This routine actually returns the index of the largest (rightmost)
3821 ** parameter. For all forms except ?NNN, this will correspond to the
3822 ** number of unique parameters. If parameters of the ?NNN form are used,
3823 ** there may be gaps in the list.)^
3825 ** See also: [sqlite3_bind_blob|sqlite3_bind()],
3826 ** [sqlite3_bind_parameter_name()], and
3827 ** [sqlite3_bind_parameter_index()].
3829 SQLITE_API int SQLITE_STDCALL sqlite3_bind_parameter_count(sqlite3_stmt*);
3832 ** CAPI3REF: Name Of A Host Parameter
3833 ** METHOD: sqlite3_stmt
3835 ** ^The sqlite3_bind_parameter_name(P,N) interface returns
3836 ** the name of the N-th [SQL parameter] in the [prepared statement] P.
3837 ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
3838 ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
3840 ** In other words, the initial ":" or "$" or "@" or "?"
3841 ** is included as part of the name.)^
3842 ** ^Parameters of the form "?" without a following integer have no name
3843 ** and are referred to as "nameless" or "anonymous parameters".
3845 ** ^The first host parameter has an index of 1, not 0.
3847 ** ^If the value N is out of range or if the N-th parameter is
3848 ** nameless, then NULL is returned. ^The returned string is
3849 ** always in UTF-8 encoding even if the named parameter was
3850 ** originally specified as UTF-16 in [sqlite3_prepare16()] or
3851 ** [sqlite3_prepare16_v2()].
3853 ** See also: [sqlite3_bind_blob|sqlite3_bind()],
3854 ** [sqlite3_bind_parameter_count()], and
3855 ** [sqlite3_bind_parameter_index()].
3857 SQLITE_API const char *SQLITE_STDCALL sqlite3_bind_parameter_name(sqlite3_stmt*, int);
3860 ** CAPI3REF: Index Of A Parameter With A Given Name
3861 ** METHOD: sqlite3_stmt
3863 ** ^Return the index of an SQL parameter given its name. ^The
3864 ** index value returned is suitable for use as the second
3865 ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
3866 ** is returned if no matching parameter is found. ^The parameter
3867 ** name must be given in UTF-8 even if the original statement
3868 ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
3870 ** See also: [sqlite3_bind_blob|sqlite3_bind()],
3871 ** [sqlite3_bind_parameter_count()], and
3872 ** [sqlite3_bind_parameter_name()].
3874 SQLITE_API int SQLITE_STDCALL sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
3877 ** CAPI3REF: Reset All Bindings On A Prepared Statement
3878 ** METHOD: sqlite3_stmt
3880 ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
3881 ** the [sqlite3_bind_blob | bindings] on a [prepared statement].
3882 ** ^Use this routine to reset all host parameters to NULL.
3884 SQLITE_API int SQLITE_STDCALL sqlite3_clear_bindings(sqlite3_stmt*);
3887 ** CAPI3REF: Number Of Columns In A Result Set
3888 ** METHOD: sqlite3_stmt
3890 ** ^Return the number of columns in the result set returned by the
3891 ** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
3892 ** statement that does not return data (for example an [UPDATE]).
3894 ** See also: [sqlite3_data_count()]
3896 SQLITE_API int SQLITE_STDCALL sqlite3_column_count(sqlite3_stmt *pStmt);
3899 ** CAPI3REF: Column Names In A Result Set
3900 ** METHOD: sqlite3_stmt
3902 ** ^These routines return the name assigned to a particular column
3903 ** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
3904 ** interface returns a pointer to a zero-terminated UTF-8 string
3905 ** and sqlite3_column_name16() returns a pointer to a zero-terminated
3906 ** UTF-16 string. ^The first parameter is the [prepared statement]
3907 ** that implements the [SELECT] statement. ^The second parameter is the
3908 ** column number. ^The leftmost column is number 0.
3910 ** ^The returned string pointer is valid until either the [prepared statement]
3911 ** is destroyed by [sqlite3_finalize()] or until the statement is automatically
3912 ** reprepared by the first call to [sqlite3_step()] for a particular run
3913 ** or until the next call to
3914 ** sqlite3_column_name() or sqlite3_column_name16() on the same column.
3916 ** ^If sqlite3_malloc() fails during the processing of either routine
3917 ** (for example during a conversion from UTF-8 to UTF-16) then a
3918 ** NULL pointer is returned.
3920 ** ^The name of a result column is the value of the "AS" clause for
3921 ** that column, if there is an AS clause. If there is no AS clause
3922 ** then the name of the column is unspecified and may change from
3923 ** one release of SQLite to the next.
3925 SQLITE_API const char *SQLITE_STDCALL sqlite3_column_name(sqlite3_stmt*, int N);
3926 SQLITE_API const void *SQLITE_STDCALL sqlite3_column_name16(sqlite3_stmt*, int N);
3929 ** CAPI3REF: Source Of Data In A Query Result
3930 ** METHOD: sqlite3_stmt
3932 ** ^These routines provide a means to determine the database, table, and
3933 ** table column that is the origin of a particular result column in
3934 ** [SELECT] statement.
3935 ** ^The name of the database or table or column can be returned as
3936 ** either a UTF-8 or UTF-16 string. ^The _database_ routines return
3937 ** the database name, the _table_ routines return the table name, and
3938 ** the origin_ routines return the column name.
3939 ** ^The returned string is valid until the [prepared statement] is destroyed
3940 ** using [sqlite3_finalize()] or until the statement is automatically
3941 ** reprepared by the first call to [sqlite3_step()] for a particular run
3942 ** or until the same information is requested
3943 ** again in a different encoding.
3945 ** ^The names returned are the original un-aliased names of the
3946 ** database, table, and column.
3948 ** ^The first argument to these interfaces is a [prepared statement].
3949 ** ^These functions return information about the Nth result column returned by
3950 ** the statement, where N is the second function argument.
3951 ** ^The left-most column is column 0 for these routines.
3953 ** ^If the Nth column returned by the statement is an expression or
3954 ** subquery and is not a column value, then all of these functions return
3955 ** NULL. ^These routine might also return NULL if a memory allocation error
3956 ** occurs. ^Otherwise, they return the name of the attached database, table,
3957 ** or column that query result column was extracted from.
3959 ** ^As with all other SQLite APIs, those whose names end with "16" return
3960 ** UTF-16 encoded strings and the other functions return UTF-8.
3962 ** ^These APIs are only available if the library was compiled with the
3963 ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
3965 ** If two or more threads call one or more of these routines against the same
3966 ** prepared statement and column at the same time then the results are
3969 ** If two or more threads call one or more
3970 ** [sqlite3_column_database_name | column metadata interfaces]
3971 ** for the same [prepared statement] and result column
3972 ** at the same time then the results are undefined.
3974 SQLITE_API const char *SQLITE_STDCALL sqlite3_column_database_name(sqlite3_stmt*,int);
3975 SQLITE_API const void *SQLITE_STDCALL sqlite3_column_database_name16(sqlite3_stmt*,int);
3976 SQLITE_API const char *SQLITE_STDCALL sqlite3_column_table_name(sqlite3_stmt*,int);
3977 SQLITE_API const void *SQLITE_STDCALL sqlite3_column_table_name16(sqlite3_stmt*,int);
3978 SQLITE_API const char *SQLITE_STDCALL sqlite3_column_origin_name(sqlite3_stmt*,int);
3979 SQLITE_API const void *SQLITE_STDCALL sqlite3_column_origin_name16(sqlite3_stmt*,int);
3982 ** CAPI3REF: Declared Datatype Of A Query Result
3983 ** METHOD: sqlite3_stmt
3985 ** ^(The first parameter is a [prepared statement].
3986 ** If this statement is a [SELECT] statement and the Nth column of the
3987 ** returned result set of that [SELECT] is a table column (not an
3988 ** expression or subquery) then the declared type of the table
3989 ** column is returned.)^ ^If the Nth column of the result set is an
3990 ** expression or subquery, then a NULL pointer is returned.
3991 ** ^The returned string is always UTF-8 encoded.
3993 ** ^(For example, given the database schema:
3995 ** CREATE TABLE t1(c1 VARIANT);
3997 ** and the following statement to be compiled:
3999 ** SELECT c1 + 1, c1 FROM t1;
4001 ** this routine would return the string "VARIANT" for the second result
4002 ** column (i==1), and a NULL pointer for the first result column (i==0).)^
4004 ** ^SQLite uses dynamic run-time typing. ^So just because a column
4005 ** is declared to contain a particular type does not mean that the
4006 ** data stored in that column is of the declared type. SQLite is
4007 ** strongly typed, but the typing is dynamic not static. ^Type
4008 ** is associated with individual values, not with the containers
4009 ** used to hold those values.
4011 SQLITE_API const char *SQLITE_STDCALL sqlite3_column_decltype(sqlite3_stmt*,int);
4012 SQLITE_API const void *SQLITE_STDCALL sqlite3_column_decltype16(sqlite3_stmt*,int);
4015 ** CAPI3REF: Evaluate An SQL Statement
4016 ** METHOD: sqlite3_stmt
4018 ** After a [prepared statement] has been prepared using either
4019 ** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
4020 ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
4021 ** must be called one or more times to evaluate the statement.
4023 ** The details of the behavior of the sqlite3_step() interface depend
4024 ** on whether the statement was prepared using the newer "v2" interface
4025 ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
4026 ** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
4027 ** new "v2" interface is recommended for new applications but the legacy
4028 ** interface will continue to be supported.
4030 ** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
4031 ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
4032 ** ^With the "v2" interface, any of the other [result codes] or
4033 ** [extended result codes] might be returned as well.
4035 ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
4036 ** database locks it needs to do its job. ^If the statement is a [COMMIT]
4037 ** or occurs outside of an explicit transaction, then you can retry the
4038 ** statement. If the statement is not a [COMMIT] and occurs within an
4039 ** explicit transaction then you should rollback the transaction before
4042 ** ^[SQLITE_DONE] means that the statement has finished executing
4043 ** successfully. sqlite3_step() should not be called again on this virtual
4044 ** machine without first calling [sqlite3_reset()] to reset the virtual
4045 ** machine back to its initial state.
4047 ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
4048 ** is returned each time a new row of data is ready for processing by the
4049 ** caller. The values may be accessed using the [column access functions].
4050 ** sqlite3_step() is called again to retrieve the next row of data.
4052 ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
4053 ** violation) has occurred. sqlite3_step() should not be called again on
4054 ** the VM. More information may be found by calling [sqlite3_errmsg()].
4055 ** ^With the legacy interface, a more specific error code (for example,
4056 ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
4057 ** can be obtained by calling [sqlite3_reset()] on the
4058 ** [prepared statement]. ^In the "v2" interface,
4059 ** the more specific error code is returned directly by sqlite3_step().
4061 ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
4062 ** Perhaps it was called on a [prepared statement] that has
4063 ** already been [sqlite3_finalize | finalized] or on one that had
4064 ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
4065 ** be the case that the same database connection is being used by two or
4066 ** more threads at the same moment in time.
4068 ** For all versions of SQLite up to and including 3.6.23.1, a call to
4069 ** [sqlite3_reset()] was required after sqlite3_step() returned anything
4070 ** other than [SQLITE_ROW] before any subsequent invocation of
4071 ** sqlite3_step(). Failure to reset the prepared statement using
4072 ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
4073 ** sqlite3_step(). But after version 3.6.23.1, sqlite3_step() began
4074 ** calling [sqlite3_reset()] automatically in this circumstance rather
4075 ** than returning [SQLITE_MISUSE]. This is not considered a compatibility
4076 ** break because any application that ever receives an SQLITE_MISUSE error
4077 ** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option
4078 ** can be used to restore the legacy behavior.
4080 ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
4081 ** API always returns a generic error code, [SQLITE_ERROR], following any
4082 ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
4083 ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
4084 ** specific [error codes] that better describes the error.
4085 ** We admit that this is a goofy design. The problem has been fixed
4086 ** with the "v2" interface. If you prepare all of your SQL statements
4087 ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
4088 ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
4089 ** then the more specific [error codes] are returned directly
4090 ** by sqlite3_step(). The use of the "v2" interface is recommended.
4092 SQLITE_API int SQLITE_STDCALL sqlite3_step(sqlite3_stmt*);
4095 ** CAPI3REF: Number of columns in a result set
4096 ** METHOD: sqlite3_stmt
4098 ** ^The sqlite3_data_count(P) interface returns the number of columns in the
4099 ** current row of the result set of [prepared statement] P.
4100 ** ^If prepared statement P does not have results ready to return
4101 ** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
4102 ** interfaces) then sqlite3_data_count(P) returns 0.
4103 ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
4104 ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
4105 ** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P)
4106 ** will return non-zero if previous call to [sqlite3_step](P) returned
4107 ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
4108 ** where it always returns zero since each step of that multi-step
4109 ** pragma returns 0 columns of data.
4111 ** See also: [sqlite3_column_count()]
4113 SQLITE_API int SQLITE_STDCALL sqlite3_data_count(sqlite3_stmt *pStmt);
4116 ** CAPI3REF: Fundamental Datatypes
4117 ** KEYWORDS: SQLITE_TEXT
4119 ** ^(Every value in SQLite has one of five fundamental datatypes:
4122 ** <li> 64-bit signed integer
4123 ** <li> 64-bit IEEE floating point number
4129 ** These constants are codes for each of those types.
4131 ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
4132 ** for a completely different meaning. Software that links against both
4133 ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
4136 #define SQLITE_INTEGER 1
4137 #define SQLITE_FLOAT 2
4138 #define SQLITE_BLOB 4
4139 #define SQLITE_NULL 5
4143 # define SQLITE_TEXT 3
4145 #define SQLITE3_TEXT 3
4148 ** CAPI3REF: Result Values From A Query
4149 ** KEYWORDS: {column access functions}
4150 ** METHOD: sqlite3_stmt
4152 ** ^These routines return information about a single column of the current
4153 ** result row of a query. ^In every case the first argument is a pointer
4154 ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
4155 ** that was returned from [sqlite3_prepare_v2()] or one of its variants)
4156 ** and the second argument is the index of the column for which information
4157 ** should be returned. ^The leftmost column of the result set has the index 0.
4158 ** ^The number of columns in the result can be determined using
4159 ** [sqlite3_column_count()].
4161 ** If the SQL statement does not currently point to a valid row, or if the
4162 ** column index is out of range, the result is undefined.
4163 ** These routines may only be called when the most recent call to
4164 ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
4165 ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
4166 ** If any of these routines are called after [sqlite3_reset()] or
4167 ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
4168 ** something other than [SQLITE_ROW], the results are undefined.
4169 ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
4170 ** are called from a different thread while any of these routines
4171 ** are pending, then the results are undefined.
4173 ** ^The sqlite3_column_type() routine returns the
4174 ** [SQLITE_INTEGER | datatype code] for the initial data type
4175 ** of the result column. ^The returned value is one of [SQLITE_INTEGER],
4176 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
4177 ** returned by sqlite3_column_type() is only meaningful if no type
4178 ** conversions have occurred as described below. After a type conversion,
4179 ** the value returned by sqlite3_column_type() is undefined. Future
4180 ** versions of SQLite may change the behavior of sqlite3_column_type()
4181 ** following a type conversion.
4183 ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
4184 ** routine returns the number of bytes in that BLOB or string.
4185 ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
4186 ** the string to UTF-8 and then returns the number of bytes.
4187 ** ^If the result is a numeric value then sqlite3_column_bytes() uses
4188 ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
4189 ** the number of bytes in that string.
4190 ** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
4192 ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
4193 ** routine returns the number of bytes in that BLOB or string.
4194 ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
4195 ** the string to UTF-16 and then returns the number of bytes.
4196 ** ^If the result is a numeric value then sqlite3_column_bytes16() uses
4197 ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
4198 ** the number of bytes in that string.
4199 ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
4201 ** ^The values returned by [sqlite3_column_bytes()] and
4202 ** [sqlite3_column_bytes16()] do not include the zero terminators at the end
4203 ** of the string. ^For clarity: the values returned by
4204 ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
4205 ** bytes in the string, not the number of characters.
4207 ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
4208 ** even empty strings, are always zero-terminated. ^The return
4209 ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
4211 ** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an
4212 ** [unprotected sqlite3_value] object. In a multithreaded environment,
4213 ** an unprotected sqlite3_value object may only be used safely with
4214 ** [sqlite3_bind_value()] and [sqlite3_result_value()].
4215 ** If the [unprotected sqlite3_value] object returned by
4216 ** [sqlite3_column_value()] is used in any other way, including calls
4217 ** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
4218 ** or [sqlite3_value_bytes()], the behavior is not threadsafe.
4220 ** These routines attempt to convert the value where appropriate. ^For
4221 ** example, if the internal representation is FLOAT and a text result
4222 ** is requested, [sqlite3_snprintf()] is used internally to perform the
4223 ** conversion automatically. ^(The following table details the conversions
4224 ** that are applied:
4227 ** <table border="1">
4228 ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
4230 ** <tr><td> NULL <td> INTEGER <td> Result is 0
4231 ** <tr><td> NULL <td> FLOAT <td> Result is 0.0
4232 ** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer
4233 ** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer
4234 ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
4235 ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
4236 ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
4237 ** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER
4238 ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
4239 ** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB
4240 ** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER
4241 ** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL
4242 ** <tr><td> TEXT <td> BLOB <td> No change
4243 ** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER
4244 ** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL
4245 ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
4249 ** Note that when type conversions occur, pointers returned by prior
4250 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
4251 ** sqlite3_column_text16() may be invalidated.
4252 ** Type conversions and pointer invalidations might occur
4253 ** in the following cases:
4256 ** <li> The initial content is a BLOB and sqlite3_column_text() or
4257 ** sqlite3_column_text16() is called. A zero-terminator might
4258 ** need to be added to the string.</li>
4259 ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
4260 ** sqlite3_column_text16() is called. The content must be converted
4262 ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
4263 ** sqlite3_column_text() is called. The content must be converted
4267 ** ^Conversions between UTF-16be and UTF-16le are always done in place and do
4268 ** not invalidate a prior pointer, though of course the content of the buffer
4269 ** that the prior pointer references will have been modified. Other kinds
4270 ** of conversion are done in place when it is possible, but sometimes they
4271 ** are not possible and in those cases prior pointers are invalidated.
4273 ** The safest policy is to invoke these routines
4274 ** in one of the following ways:
4277 ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
4278 ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
4279 ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
4282 ** In other words, you should call sqlite3_column_text(),
4283 ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
4284 ** into the desired format, then invoke sqlite3_column_bytes() or
4285 ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
4286 ** to sqlite3_column_text() or sqlite3_column_blob() with calls to
4287 ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
4288 ** with calls to sqlite3_column_bytes().
4290 ** ^The pointers returned are valid until a type conversion occurs as
4291 ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
4292 ** [sqlite3_finalize()] is called. ^The memory space used to hold strings
4293 ** and BLOBs is freed automatically. Do <em>not</em> pass the pointers returned
4294 ** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
4295 ** [sqlite3_free()].
4297 ** ^(If a memory allocation error occurs during the evaluation of any
4298 ** of these routines, a default value is returned. The default value
4299 ** is either the integer 0, the floating point number 0.0, or a NULL
4300 ** pointer. Subsequent calls to [sqlite3_errcode()] will return
4301 ** [SQLITE_NOMEM].)^
4303 SQLITE_API const void *SQLITE_STDCALL sqlite3_column_blob(sqlite3_stmt*, int iCol);
4304 SQLITE_API int SQLITE_STDCALL sqlite3_column_bytes(sqlite3_stmt*, int iCol);
4305 SQLITE_API int SQLITE_STDCALL sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
4306 SQLITE_API double SQLITE_STDCALL sqlite3_column_double(sqlite3_stmt*, int iCol);
4307 SQLITE_API int SQLITE_STDCALL sqlite3_column_int(sqlite3_stmt*, int iCol);
4308 SQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_column_int64(sqlite3_stmt*, int iCol);
4309 SQLITE_API const unsigned char *SQLITE_STDCALL sqlite3_column_text(sqlite3_stmt*, int iCol);
4310 SQLITE_API const void *SQLITE_STDCALL sqlite3_column_text16(sqlite3_stmt*, int iCol);
4311 SQLITE_API int SQLITE_STDCALL sqlite3_column_type(sqlite3_stmt*, int iCol);
4312 SQLITE_API sqlite3_value *SQLITE_STDCALL sqlite3_column_value(sqlite3_stmt*, int iCol);
4315 ** CAPI3REF: Destroy A Prepared Statement Object
4316 ** DESTRUCTOR: sqlite3_stmt
4318 ** ^The sqlite3_finalize() function is called to delete a [prepared statement].
4319 ** ^If the most recent evaluation of the statement encountered no errors
4320 ** or if the statement is never been evaluated, then sqlite3_finalize() returns
4321 ** SQLITE_OK. ^If the most recent evaluation of statement S failed, then
4322 ** sqlite3_finalize(S) returns the appropriate [error code] or
4323 ** [extended error code].
4325 ** ^The sqlite3_finalize(S) routine can be called at any point during
4326 ** the life cycle of [prepared statement] S:
4327 ** before statement S is ever evaluated, after
4328 ** one or more calls to [sqlite3_reset()], or after any call
4329 ** to [sqlite3_step()] regardless of whether or not the statement has
4330 ** completed execution.
4332 ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
4334 ** The application must finalize every [prepared statement] in order to avoid
4335 ** resource leaks. It is a grievous error for the application to try to use
4336 ** a prepared statement after it has been finalized. Any use of a prepared
4337 ** statement after it has been finalized can result in undefined and
4338 ** undesirable behavior such as segfaults and heap corruption.
4340 SQLITE_API int SQLITE_STDCALL sqlite3_finalize(sqlite3_stmt *pStmt);
4343 ** CAPI3REF: Reset A Prepared Statement Object
4344 ** METHOD: sqlite3_stmt
4346 ** The sqlite3_reset() function is called to reset a [prepared statement]
4347 ** object back to its initial state, ready to be re-executed.
4348 ** ^Any SQL statement variables that had values bound to them using
4349 ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
4350 ** Use [sqlite3_clear_bindings()] to reset the bindings.
4352 ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
4353 ** back to the beginning of its program.
4355 ** ^If the most recent call to [sqlite3_step(S)] for the
4356 ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
4357 ** or if [sqlite3_step(S)] has never before been called on S,
4358 ** then [sqlite3_reset(S)] returns [SQLITE_OK].
4360 ** ^If the most recent call to [sqlite3_step(S)] for the
4361 ** [prepared statement] S indicated an error, then
4362 ** [sqlite3_reset(S)] returns an appropriate [error code].
4364 ** ^The [sqlite3_reset(S)] interface does not change the values
4365 ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
4367 SQLITE_API int SQLITE_STDCALL sqlite3_reset(sqlite3_stmt *pStmt);
4370 ** CAPI3REF: Create Or Redefine SQL Functions
4371 ** KEYWORDS: {function creation routines}
4372 ** KEYWORDS: {application-defined SQL function}
4373 ** KEYWORDS: {application-defined SQL functions}
4376 ** ^These functions (collectively known as "function creation routines")
4377 ** are used to add SQL functions or aggregates or to redefine the behavior
4378 ** of existing SQL functions or aggregates. The only differences between
4379 ** these routines are the text encoding expected for
4380 ** the second parameter (the name of the function being created)
4381 ** and the presence or absence of a destructor callback for
4382 ** the application data pointer.
4384 ** ^The first parameter is the [database connection] to which the SQL
4385 ** function is to be added. ^If an application uses more than one database
4386 ** connection then application-defined SQL functions must be added
4387 ** to each database connection separately.
4389 ** ^The second parameter is the name of the SQL function to be created or
4390 ** redefined. ^The length of the name is limited to 255 bytes in a UTF-8
4391 ** representation, exclusive of the zero-terminator. ^Note that the name
4392 ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
4393 ** ^Any attempt to create a function with a longer name
4394 ** will result in [SQLITE_MISUSE] being returned.
4396 ** ^The third parameter (nArg)
4397 ** is the number of arguments that the SQL function or
4398 ** aggregate takes. ^If this parameter is -1, then the SQL function or
4399 ** aggregate may take any number of arguments between 0 and the limit
4400 ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
4401 ** parameter is less than -1 or greater than 127 then the behavior is
4404 ** ^The fourth parameter, eTextRep, specifies what
4405 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
4406 ** its parameters. The application should set this parameter to
4407 ** [SQLITE_UTF16LE] if the function implementation invokes
4408 ** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
4409 ** implementation invokes [sqlite3_value_text16be()] on an input, or
4410 ** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
4411 ** otherwise. ^The same SQL function may be registered multiple times using
4412 ** different preferred text encodings, with different implementations for
4414 ** ^When multiple implementations of the same function are available, SQLite
4415 ** will pick the one that involves the least amount of data conversion.
4417 ** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
4418 ** to signal that the function will always return the same result given
4419 ** the same inputs within a single SQL statement. Most SQL functions are
4420 ** deterministic. The built-in [random()] SQL function is an example of a
4421 ** function that is not deterministic. The SQLite query planner is able to
4422 ** perform additional optimizations on deterministic functions, so use
4423 ** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
4425 ** ^(The fifth parameter is an arbitrary pointer. The implementation of the
4426 ** function can gain access to this pointer using [sqlite3_user_data()].)^
4428 ** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are
4429 ** pointers to C-language functions that implement the SQL function or
4430 ** aggregate. ^A scalar SQL function requires an implementation of the xFunc
4431 ** callback only; NULL pointers must be passed as the xStep and xFinal
4432 ** parameters. ^An aggregate SQL function requires an implementation of xStep
4433 ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
4434 ** SQL function or aggregate, pass NULL pointers for all three function
4437 ** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,
4438 ** then it is destructor for the application data pointer.
4439 ** The destructor is invoked when the function is deleted, either by being
4440 ** overloaded or when the database connection closes.)^
4441 ** ^The destructor is also invoked if the call to
4442 ** sqlite3_create_function_v2() fails.
4443 ** ^When the destructor callback of the tenth parameter is invoked, it
4444 ** is passed a single argument which is a copy of the application data
4445 ** pointer which was the fifth parameter to sqlite3_create_function_v2().
4447 ** ^It is permitted to register multiple implementations of the same
4448 ** functions with the same name but with either differing numbers of
4449 ** arguments or differing preferred text encodings. ^SQLite will use
4450 ** the implementation that most closely matches the way in which the
4451 ** SQL function is used. ^A function implementation with a non-negative
4452 ** nArg parameter is a better match than a function implementation with
4453 ** a negative nArg. ^A function where the preferred text encoding
4454 ** matches the database encoding is a better
4455 ** match than a function where the encoding is different.
4456 ** ^A function where the encoding difference is between UTF16le and UTF16be
4457 ** is a closer match than a function where the encoding difference is
4458 ** between UTF8 and UTF16.
4460 ** ^Built-in functions may be overloaded by new application-defined functions.
4462 ** ^An application-defined function is permitted to call other
4463 ** SQLite interfaces. However, such calls must not
4464 ** close the database connection nor finalize or reset the prepared
4465 ** statement in which the function is running.
4467 SQLITE_API int SQLITE_STDCALL sqlite3_create_function(
4469 const char *zFunctionName,
4473 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
4474 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
4475 void (*xFinal)(sqlite3_context*)
4477 SQLITE_API int SQLITE_STDCALL sqlite3_create_function16(
4479 const void *zFunctionName,
4483 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
4484 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
4485 void (*xFinal)(sqlite3_context*)
4487 SQLITE_API int SQLITE_STDCALL sqlite3_create_function_v2(
4489 const char *zFunctionName,
4493 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
4494 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
4495 void (*xFinal)(sqlite3_context*),
4496 void(*xDestroy)(void*)
4500 ** CAPI3REF: Text Encodings
4502 ** These constant define integer codes that represent the various
4503 ** text encodings supported by SQLite.
4505 #define SQLITE_UTF8 1 /* IMP: R-37514-35566 */
4506 #define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */
4507 #define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */
4508 #define SQLITE_UTF16 4 /* Use native byte order */
4509 #define SQLITE_ANY 5 /* Deprecated */
4510 #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
4513 ** CAPI3REF: Function Flags
4515 ** These constants may be ORed together with the
4516 ** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
4517 ** to [sqlite3_create_function()], [sqlite3_create_function16()], or
4518 ** [sqlite3_create_function_v2()].
4520 #define SQLITE_DETERMINISTIC 0x800
4523 ** CAPI3REF: Deprecated Functions
4526 ** These functions are [deprecated]. In order to maintain
4527 ** backwards compatibility with older code, these functions continue
4528 ** to be supported. However, new applications should avoid
4529 ** the use of these functions. To encourage programmers to avoid
4530 ** these functions, we will not explain what they do.
4532 #ifndef SQLITE_OMIT_DEPRECATED
4533 SQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_aggregate_count(sqlite3_context*);
4534 SQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_expired(sqlite3_stmt*);
4535 SQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
4536 SQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_global_recover(void);
4537 SQLITE_API SQLITE_DEPRECATED void SQLITE_STDCALL sqlite3_thread_cleanup(void);
4538 SQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
4539 void*,sqlite3_int64);
4543 ** CAPI3REF: Obtaining SQL Values
4544 ** METHOD: sqlite3_value
4546 ** The C-language implementation of SQL functions and aggregates uses
4547 ** this set of interface routines to access the parameter values on
4548 ** the function or aggregate.
4550 ** The xFunc (for scalar functions) or xStep (for aggregates) parameters
4551 ** to [sqlite3_create_function()] and [sqlite3_create_function16()]
4552 ** define callbacks that implement the SQL functions and aggregates.
4553 ** The 3rd parameter to these callbacks is an array of pointers to
4554 ** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
4555 ** each parameter to the SQL function. These routines are used to
4556 ** extract values from the [sqlite3_value] objects.
4558 ** These routines work only with [protected sqlite3_value] objects.
4559 ** Any attempt to use these routines on an [unprotected sqlite3_value]
4560 ** object results in undefined behavior.
4562 ** ^These routines work just like the corresponding [column access functions]
4563 ** except that these routines take a single [protected sqlite3_value] object
4564 ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
4566 ** ^The sqlite3_value_text16() interface extracts a UTF-16 string
4567 ** in the native byte-order of the host machine. ^The
4568 ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
4569 ** extract UTF-16 strings as big-endian and little-endian respectively.
4571 ** ^(The sqlite3_value_numeric_type() interface attempts to apply
4572 ** numeric affinity to the value. This means that an attempt is
4573 ** made to convert the value to an integer or floating point. If
4574 ** such a conversion is possible without loss of information (in other
4575 ** words, if the value is a string that looks like a number)
4576 ** then the conversion is performed. Otherwise no conversion occurs.
4577 ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
4579 ** Please pay particular attention to the fact that the pointer returned
4580 ** from [sqlite3_value_blob()], [sqlite3_value_text()], or
4581 ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
4582 ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
4583 ** or [sqlite3_value_text16()].
4585 ** These routines must be called from the same thread as
4586 ** the SQL function that supplied the [sqlite3_value*] parameters.
4588 SQLITE_API const void *SQLITE_STDCALL sqlite3_value_blob(sqlite3_value*);
4589 SQLITE_API int SQLITE_STDCALL sqlite3_value_bytes(sqlite3_value*);
4590 SQLITE_API int SQLITE_STDCALL sqlite3_value_bytes16(sqlite3_value*);
4591 SQLITE_API double SQLITE_STDCALL sqlite3_value_double(sqlite3_value*);
4592 SQLITE_API int SQLITE_STDCALL sqlite3_value_int(sqlite3_value*);
4593 SQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_value_int64(sqlite3_value*);
4594 SQLITE_API const unsigned char *SQLITE_STDCALL sqlite3_value_text(sqlite3_value*);
4595 SQLITE_API const void *SQLITE_STDCALL sqlite3_value_text16(sqlite3_value*);
4596 SQLITE_API const void *SQLITE_STDCALL sqlite3_value_text16le(sqlite3_value*);
4597 SQLITE_API const void *SQLITE_STDCALL sqlite3_value_text16be(sqlite3_value*);
4598 SQLITE_API int SQLITE_STDCALL sqlite3_value_type(sqlite3_value*);
4599 SQLITE_API int SQLITE_STDCALL sqlite3_value_numeric_type(sqlite3_value*);
4602 ** CAPI3REF: Finding The Subtype Of SQL Values
4603 ** METHOD: sqlite3_value
4605 ** The sqlite3_value_subtype(V) function returns the subtype for
4606 ** an [application-defined SQL function] argument V. The subtype
4607 ** information can be used to pass a limited amount of context from
4608 ** one SQL function to another. Use the [sqlite3_result_subtype()]
4609 ** routine to set the subtype for the return value of an SQL function.
4611 ** SQLite makes no use of subtype itself. It merely passes the subtype
4612 ** from the result of one [application-defined SQL function] into the
4613 ** input of another.
4615 SQLITE_API unsigned int SQLITE_STDCALL sqlite3_value_subtype(sqlite3_value*);
4618 ** CAPI3REF: Copy And Free SQL Values
4619 ** METHOD: sqlite3_value
4621 ** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value]
4622 ** object D and returns a pointer to that copy. ^The [sqlite3_value] returned
4623 ** is a [protected sqlite3_value] object even if the input is not.
4624 ** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a
4625 ** memory allocation fails.
4627 ** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object
4628 ** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer
4629 ** then sqlite3_value_free(V) is a harmless no-op.
4631 SQLITE_API sqlite3_value *SQLITE_STDCALL sqlite3_value_dup(const sqlite3_value*);
4632 SQLITE_API void SQLITE_STDCALL sqlite3_value_free(sqlite3_value*);
4635 ** CAPI3REF: Obtain Aggregate Function Context
4636 ** METHOD: sqlite3_context
4638 ** Implementations of aggregate SQL functions use this
4639 ** routine to allocate memory for storing their state.
4641 ** ^The first time the sqlite3_aggregate_context(C,N) routine is called
4642 ** for a particular aggregate function, SQLite
4643 ** allocates N of memory, zeroes out that memory, and returns a pointer
4644 ** to the new memory. ^On second and subsequent calls to
4645 ** sqlite3_aggregate_context() for the same aggregate function instance,
4646 ** the same buffer is returned. Sqlite3_aggregate_context() is normally
4647 ** called once for each invocation of the xStep callback and then one
4648 ** last time when the xFinal callback is invoked. ^(When no rows match
4649 ** an aggregate query, the xStep() callback of the aggregate function
4650 ** implementation is never called and xFinal() is called exactly once.
4651 ** In those cases, sqlite3_aggregate_context() might be called for the
4652 ** first time from within xFinal().)^
4654 ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
4655 ** when first called if N is less than or equal to zero or if a memory
4656 ** allocate error occurs.
4658 ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
4659 ** determined by the N parameter on first successful call. Changing the
4660 ** value of N in subsequent call to sqlite3_aggregate_context() within
4661 ** the same aggregate function instance will not resize the memory
4662 ** allocation.)^ Within the xFinal callback, it is customary to set
4663 ** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
4664 ** pointless memory allocations occur.
4666 ** ^SQLite automatically frees the memory allocated by
4667 ** sqlite3_aggregate_context() when the aggregate query concludes.
4669 ** The first parameter must be a copy of the
4670 ** [sqlite3_context | SQL function context] that is the first parameter
4671 ** to the xStep or xFinal callback routine that implements the aggregate
4674 ** This routine must be called from the same thread in which
4675 ** the aggregate SQL function is running.
4677 SQLITE_API void *SQLITE_STDCALL sqlite3_aggregate_context(sqlite3_context*, int nBytes);
4680 ** CAPI3REF: User Data For Functions
4681 ** METHOD: sqlite3_context
4683 ** ^The sqlite3_user_data() interface returns a copy of
4684 ** the pointer that was the pUserData parameter (the 5th parameter)
4685 ** of the [sqlite3_create_function()]
4686 ** and [sqlite3_create_function16()] routines that originally
4687 ** registered the application defined function.
4689 ** This routine must be called from the same thread in which
4690 ** the application-defined function is running.
4692 SQLITE_API void *SQLITE_STDCALL sqlite3_user_data(sqlite3_context*);
4695 ** CAPI3REF: Database Connection For Functions
4696 ** METHOD: sqlite3_context
4698 ** ^The sqlite3_context_db_handle() interface returns a copy of
4699 ** the pointer to the [database connection] (the 1st parameter)
4700 ** of the [sqlite3_create_function()]
4701 ** and [sqlite3_create_function16()] routines that originally
4702 ** registered the application defined function.
4704 SQLITE_API sqlite3 *SQLITE_STDCALL sqlite3_context_db_handle(sqlite3_context*);
4707 ** CAPI3REF: Function Auxiliary Data
4708 ** METHOD: sqlite3_context
4710 ** These functions may be used by (non-aggregate) SQL functions to
4711 ** associate metadata with argument values. If the same value is passed to
4712 ** multiple invocations of the same SQL function during query execution, under
4713 ** some circumstances the associated metadata may be preserved. An example
4714 ** of where this might be useful is in a regular-expression matching
4715 ** function. The compiled version of the regular expression can be stored as
4716 ** metadata associated with the pattern string.
4717 ** Then as long as the pattern string remains the same,
4718 ** the compiled regular expression can be reused on multiple
4719 ** invocations of the same function.
4721 ** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
4722 ** associated by the sqlite3_set_auxdata() function with the Nth argument
4723 ** value to the application-defined function. ^If there is no metadata
4724 ** associated with the function argument, this sqlite3_get_auxdata() interface
4725 ** returns a NULL pointer.
4727 ** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
4728 ** argument of the application-defined function. ^Subsequent
4729 ** calls to sqlite3_get_auxdata(C,N) return P from the most recent
4730 ** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
4731 ** NULL if the metadata has been discarded.
4732 ** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
4733 ** SQLite will invoke the destructor function X with parameter P exactly
4734 ** once, when the metadata is discarded.
4735 ** SQLite is free to discard the metadata at any time, including: <ul>
4736 ** <li> when the corresponding function parameter changes, or
4737 ** <li> when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
4738 ** SQL statement, or
4739 ** <li> when sqlite3_set_auxdata() is invoked again on the same parameter, or
4740 ** <li> during the original sqlite3_set_auxdata() call when a memory
4741 ** allocation error occurs. </ul>)^
4743 ** Note the last bullet in particular. The destructor X in
4744 ** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
4745 ** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata()
4746 ** should be called near the end of the function implementation and the
4747 ** function implementation should not make any use of P after
4748 ** sqlite3_set_auxdata() has been called.
4750 ** ^(In practice, metadata is preserved between function calls for
4751 ** function parameters that are compile-time constants, including literal
4752 ** values and [parameters] and expressions composed from the same.)^
4754 ** These routines must be called from the same thread in which
4755 ** the SQL function is running.
4757 SQLITE_API void *SQLITE_STDCALL sqlite3_get_auxdata(sqlite3_context*, int N);
4758 SQLITE_API void SQLITE_STDCALL sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
4762 ** CAPI3REF: Constants Defining Special Destructor Behavior
4764 ** These are special values for the destructor that is passed in as the
4765 ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
4766 ** argument is SQLITE_STATIC, it means that the content pointer is constant
4767 ** and will never change. It does not need to be destroyed. ^The
4768 ** SQLITE_TRANSIENT value means that the content will likely change in
4769 ** the near future and that SQLite should make its own private copy of
4770 ** the content before returning.
4772 ** The typedef is necessary to work around problems in certain
4775 typedef void (*sqlite3_destructor_type)(void*);
4776 #define SQLITE_STATIC ((sqlite3_destructor_type)0)
4777 #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
4780 ** CAPI3REF: Setting The Result Of An SQL Function
4781 ** METHOD: sqlite3_context
4783 ** These routines are used by the xFunc or xFinal callbacks that
4784 ** implement SQL functions and aggregates. See
4785 ** [sqlite3_create_function()] and [sqlite3_create_function16()]
4786 ** for additional information.
4788 ** These functions work very much like the [parameter binding] family of
4789 ** functions used to bind values to host parameters in prepared statements.
4790 ** Refer to the [SQL parameter] documentation for additional information.
4792 ** ^The sqlite3_result_blob() interface sets the result from
4793 ** an application-defined function to be the BLOB whose content is pointed
4794 ** to by the second parameter and which is N bytes long where N is the
4797 ** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N)
4798 ** interfaces set the result of the application-defined function to be
4799 ** a BLOB containing all zero bytes and N bytes in size.
4801 ** ^The sqlite3_result_double() interface sets the result from
4802 ** an application-defined function to be a floating point value specified
4803 ** by its 2nd argument.
4805 ** ^The sqlite3_result_error() and sqlite3_result_error16() functions
4806 ** cause the implemented SQL function to throw an exception.
4807 ** ^SQLite uses the string pointed to by the
4808 ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
4809 ** as the text of an error message. ^SQLite interprets the error
4810 ** message string from sqlite3_result_error() as UTF-8. ^SQLite
4811 ** interprets the string from sqlite3_result_error16() as UTF-16 in native
4812 ** byte order. ^If the third parameter to sqlite3_result_error()
4813 ** or sqlite3_result_error16() is negative then SQLite takes as the error
4814 ** message all text up through the first zero character.
4815 ** ^If the third parameter to sqlite3_result_error() or
4816 ** sqlite3_result_error16() is non-negative then SQLite takes that many
4817 ** bytes (not characters) from the 2nd parameter as the error message.
4818 ** ^The sqlite3_result_error() and sqlite3_result_error16()
4819 ** routines make a private copy of the error message text before
4820 ** they return. Hence, the calling function can deallocate or
4821 ** modify the text after they return without harm.
4822 ** ^The sqlite3_result_error_code() function changes the error code
4823 ** returned by SQLite as a result of an error in a function. ^By default,
4824 ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
4825 ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
4827 ** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
4828 ** error indicating that a string or BLOB is too long to represent.
4830 ** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
4831 ** error indicating that a memory allocation failed.
4833 ** ^The sqlite3_result_int() interface sets the return value
4834 ** of the application-defined function to be the 32-bit signed integer
4835 ** value given in the 2nd argument.
4836 ** ^The sqlite3_result_int64() interface sets the return value
4837 ** of the application-defined function to be the 64-bit signed integer
4838 ** value given in the 2nd argument.
4840 ** ^The sqlite3_result_null() interface sets the return value
4841 ** of the application-defined function to be NULL.
4843 ** ^The sqlite3_result_text(), sqlite3_result_text16(),
4844 ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
4845 ** set the return value of the application-defined function to be
4846 ** a text string which is represented as UTF-8, UTF-16 native byte order,
4847 ** UTF-16 little endian, or UTF-16 big endian, respectively.
4848 ** ^The sqlite3_result_text64() interface sets the return value of an
4849 ** application-defined function to be a text string in an encoding
4850 ** specified by the fifth (and last) parameter, which must be one
4851 ** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
4852 ** ^SQLite takes the text result from the application from
4853 ** the 2nd parameter of the sqlite3_result_text* interfaces.
4854 ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
4855 ** is negative, then SQLite takes result text from the 2nd parameter
4856 ** through the first zero character.
4857 ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
4858 ** is non-negative, then as many bytes (not characters) of the text
4859 ** pointed to by the 2nd parameter are taken as the application-defined
4860 ** function result. If the 3rd parameter is non-negative, then it
4861 ** must be the byte offset into the string where the NUL terminator would
4862 ** appear if the string where NUL terminated. If any NUL characters occur
4863 ** in the string at a byte offset that is less than the value of the 3rd
4864 ** parameter, then the resulting string will contain embedded NULs and the
4865 ** result of expressions operating on strings with embedded NULs is undefined.
4866 ** ^If the 4th parameter to the sqlite3_result_text* interfaces
4867 ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
4868 ** function as the destructor on the text or BLOB result when it has
4869 ** finished using that result.
4870 ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
4871 ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
4872 ** assumes that the text or BLOB result is in constant space and does not
4873 ** copy the content of the parameter nor call a destructor on the content
4874 ** when it has finished using that result.
4875 ** ^If the 4th parameter to the sqlite3_result_text* interfaces
4876 ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
4877 ** then SQLite makes a copy of the result into space obtained from
4878 ** from [sqlite3_malloc()] before it returns.
4880 ** ^The sqlite3_result_value() interface sets the result of
4881 ** the application-defined function to be a copy of the
4882 ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
4883 ** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
4884 ** so that the [sqlite3_value] specified in the parameter may change or
4885 ** be deallocated after sqlite3_result_value() returns without harm.
4886 ** ^A [protected sqlite3_value] object may always be used where an
4887 ** [unprotected sqlite3_value] object is required, so either
4888 ** kind of [sqlite3_value] object can be used with this interface.
4890 ** If these routines are called from within the different thread
4891 ** than the one containing the application-defined function that received
4892 ** the [sqlite3_context] pointer, the results are undefined.
4894 SQLITE_API void SQLITE_STDCALL sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
4895 SQLITE_API void SQLITE_STDCALL sqlite3_result_blob64(sqlite3_context*,const void*,
4896 sqlite3_uint64,void(*)(void*));
4897 SQLITE_API void SQLITE_STDCALL sqlite3_result_double(sqlite3_context*, double);
4898 SQLITE_API void SQLITE_STDCALL sqlite3_result_error(sqlite3_context*, const char*, int);
4899 SQLITE_API void SQLITE_STDCALL sqlite3_result_error16(sqlite3_context*, const void*, int);
4900 SQLITE_API void SQLITE_STDCALL sqlite3_result_error_toobig(sqlite3_context*);
4901 SQLITE_API void SQLITE_STDCALL sqlite3_result_error_nomem(sqlite3_context*);
4902 SQLITE_API void SQLITE_STDCALL sqlite3_result_error_code(sqlite3_context*, int);
4903 SQLITE_API void SQLITE_STDCALL sqlite3_result_int(sqlite3_context*, int);
4904 SQLITE_API void SQLITE_STDCALL sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
4905 SQLITE_API void SQLITE_STDCALL sqlite3_result_null(sqlite3_context*);
4906 SQLITE_API void SQLITE_STDCALL sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
4907 SQLITE_API void SQLITE_STDCALL sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64,
4908 void(*)(void*), unsigned char encoding);
4909 SQLITE_API void SQLITE_STDCALL sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
4910 SQLITE_API void SQLITE_STDCALL sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
4911 SQLITE_API void SQLITE_STDCALL sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
4912 SQLITE_API void SQLITE_STDCALL sqlite3_result_value(sqlite3_context*, sqlite3_value*);
4913 SQLITE_API void SQLITE_STDCALL sqlite3_result_zeroblob(sqlite3_context*, int n);
4914 SQLITE_API int SQLITE_STDCALL sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n);
4918 ** CAPI3REF: Setting The Subtype Of An SQL Function
4919 ** METHOD: sqlite3_context
4921 ** The sqlite3_result_subtype(C,T) function causes the subtype of
4922 ** the result from the [application-defined SQL function] with
4923 ** [sqlite3_context] C to be the value T. Only the lower 8 bits
4924 ** of the subtype T are preserved in current versions of SQLite;
4925 ** higher order bits are discarded.
4926 ** The number of subtype bytes preserved by SQLite might increase
4927 ** in future releases of SQLite.
4929 SQLITE_API void SQLITE_STDCALL sqlite3_result_subtype(sqlite3_context*,unsigned int);
4932 ** CAPI3REF: Define New Collating Sequences
4935 ** ^These functions add, remove, or modify a [collation] associated
4936 ** with the [database connection] specified as the first argument.
4938 ** ^The name of the collation is a UTF-8 string
4939 ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
4940 ** and a UTF-16 string in native byte order for sqlite3_create_collation16().
4941 ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
4942 ** considered to be the same name.
4944 ** ^(The third argument (eTextRep) must be one of the constants:
4946 ** <li> [SQLITE_UTF8],
4947 ** <li> [SQLITE_UTF16LE],
4948 ** <li> [SQLITE_UTF16BE],
4949 ** <li> [SQLITE_UTF16], or
4950 ** <li> [SQLITE_UTF16_ALIGNED].
4952 ** ^The eTextRep argument determines the encoding of strings passed
4953 ** to the collating function callback, xCallback.
4954 ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
4955 ** force strings to be UTF16 with native byte order.
4956 ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
4957 ** on an even byte address.
4959 ** ^The fourth argument, pArg, is an application data pointer that is passed
4960 ** through as the first argument to the collating function callback.
4962 ** ^The fifth argument, xCallback, is a pointer to the collating function.
4963 ** ^Multiple collating functions can be registered using the same name but
4964 ** with different eTextRep parameters and SQLite will use whichever
4965 ** function requires the least amount of data transformation.
4966 ** ^If the xCallback argument is NULL then the collating function is
4967 ** deleted. ^When all collating functions having the same name are deleted,
4968 ** that collation is no longer usable.
4970 ** ^The collating function callback is invoked with a copy of the pArg
4971 ** application data pointer and with two strings in the encoding specified
4972 ** by the eTextRep argument. The collating function must return an
4973 ** integer that is negative, zero, or positive
4974 ** if the first string is less than, equal to, or greater than the second,
4975 ** respectively. A collating function must always return the same answer
4976 ** given the same inputs. If two or more collating functions are registered
4977 ** to the same collation name (using different eTextRep values) then all
4978 ** must give an equivalent answer when invoked with equivalent strings.
4979 ** The collating function must obey the following properties for all
4980 ** strings A, B, and C:
4983 ** <li> If A==B then B==A.
4984 ** <li> If A==B and B==C then A==C.
4985 ** <li> If A<B THEN B>A.
4986 ** <li> If A<B and B<C then A<C.
4989 ** If a collating function fails any of the above constraints and that
4990 ** collating function is registered and used, then the behavior of SQLite
4993 ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
4994 ** with the addition that the xDestroy callback is invoked on pArg when
4995 ** the collating function is deleted.
4996 ** ^Collating functions are deleted when they are overridden by later
4997 ** calls to the collation creation functions or when the
4998 ** [database connection] is closed using [sqlite3_close()].
5000 ** ^The xDestroy callback is <u>not</u> called if the
5001 ** sqlite3_create_collation_v2() function fails. Applications that invoke
5002 ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
5003 ** check the return code and dispose of the application data pointer
5004 ** themselves rather than expecting SQLite to deal with it for them.
5005 ** This is different from every other SQLite interface. The inconsistency
5006 ** is unfortunate but cannot be changed without breaking backwards
5009 ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
5011 SQLITE_API int SQLITE_STDCALL sqlite3_create_collation(
5016 int(*xCompare)(void*,int,const void*,int,const void*)
5018 SQLITE_API int SQLITE_STDCALL sqlite3_create_collation_v2(
5023 int(*xCompare)(void*,int,const void*,int,const void*),
5024 void(*xDestroy)(void*)
5026 SQLITE_API int SQLITE_STDCALL sqlite3_create_collation16(
5031 int(*xCompare)(void*,int,const void*,int,const void*)
5035 ** CAPI3REF: Collation Needed Callbacks
5038 ** ^To avoid having to register all collation sequences before a database
5039 ** can be used, a single callback function may be registered with the
5040 ** [database connection] to be invoked whenever an undefined collation
5041 ** sequence is required.
5043 ** ^If the function is registered using the sqlite3_collation_needed() API,
5044 ** then it is passed the names of undefined collation sequences as strings
5045 ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
5046 ** the names are passed as UTF-16 in machine native byte order.
5047 ** ^A call to either function replaces the existing collation-needed callback.
5049 ** ^(When the callback is invoked, the first argument passed is a copy
5050 ** of the second argument to sqlite3_collation_needed() or
5051 ** sqlite3_collation_needed16(). The second argument is the database
5052 ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
5053 ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
5054 ** sequence function required. The fourth parameter is the name of the
5055 ** required collation sequence.)^
5057 ** The callback function should register the desired collation using
5058 ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
5059 ** [sqlite3_create_collation_v2()].
5061 SQLITE_API int SQLITE_STDCALL sqlite3_collation_needed(
5064 void(*)(void*,sqlite3*,int eTextRep,const char*)
5066 SQLITE_API int SQLITE_STDCALL sqlite3_collation_needed16(
5069 void(*)(void*,sqlite3*,int eTextRep,const void*)
5072 #ifdef SQLITE_HAS_CODEC
5074 ** Specify the key for an encrypted database. This routine should be
5075 ** called right after sqlite3_open().
5077 ** The code to implement this API is not available in the public release
5080 SQLITE_API int SQLITE_STDCALL sqlite3_key(
5081 sqlite3 *db, /* Database to be rekeyed */
5082 const void *pKey, int nKey /* The key */
5084 SQLITE_API int SQLITE_STDCALL sqlite3_key_v2(
5085 sqlite3 *db, /* Database to be rekeyed */
5086 const char *zDbName, /* Name of the database */
5087 const void *pKey, int nKey /* The key */
5091 ** Change the key on an open database. If the current database is not
5092 ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
5093 ** database is decrypted.
5095 ** The code to implement this API is not available in the public release
5098 SQLITE_API int SQLITE_STDCALL sqlite3_rekey(
5099 sqlite3 *db, /* Database to be rekeyed */
5100 const void *pKey, int nKey /* The new key */
5102 SQLITE_API int SQLITE_STDCALL sqlite3_rekey_v2(
5103 sqlite3 *db, /* Database to be rekeyed */
5104 const char *zDbName, /* Name of the database */
5105 const void *pKey, int nKey /* The new key */
5109 ** Specify the activation key for a SEE database. Unless
5110 ** activated, none of the SEE routines will work.
5112 SQLITE_API void SQLITE_STDCALL sqlite3_activate_see(
5113 const char *zPassPhrase /* Activation phrase */
5117 #ifdef SQLITE_ENABLE_CEROD
5119 ** Specify the activation key for a CEROD database. Unless
5120 ** activated, none of the CEROD routines will work.
5122 SQLITE_API void SQLITE_STDCALL sqlite3_activate_cerod(
5123 const char *zPassPhrase /* Activation phrase */
5128 ** CAPI3REF: Suspend Execution For A Short Time
5130 ** The sqlite3_sleep() function causes the current thread to suspend execution
5131 ** for at least a number of milliseconds specified in its parameter.
5133 ** If the operating system does not support sleep requests with
5134 ** millisecond time resolution, then the time will be rounded up to
5135 ** the nearest second. The number of milliseconds of sleep actually
5136 ** requested from the operating system is returned.
5138 ** ^SQLite implements this interface by calling the xSleep()
5139 ** method of the default [sqlite3_vfs] object. If the xSleep() method
5140 ** of the default VFS is not implemented correctly, or not implemented at
5141 ** all, then the behavior of sqlite3_sleep() may deviate from the description
5142 ** in the previous paragraphs.
5144 SQLITE_API int SQLITE_STDCALL sqlite3_sleep(int);
5147 ** CAPI3REF: Name Of The Folder Holding Temporary Files
5149 ** ^(If this global variable is made to point to a string which is
5150 ** the name of a folder (a.k.a. directory), then all temporary files
5151 ** created by SQLite when using a built-in [sqlite3_vfs | VFS]
5152 ** will be placed in that directory.)^ ^If this variable
5153 ** is a NULL pointer, then SQLite performs a search for an appropriate
5154 ** temporary file directory.
5156 ** Applications are strongly discouraged from using this global variable.
5157 ** It is required to set a temporary folder on Windows Runtime (WinRT).
5158 ** But for all other platforms, it is highly recommended that applications
5159 ** neither read nor write this variable. This global variable is a relic
5160 ** that exists for backwards compatibility of legacy applications and should
5161 ** be avoided in new projects.
5163 ** It is not safe to read or modify this variable in more than one
5164 ** thread at a time. It is not safe to read or modify this variable
5165 ** if a [database connection] is being used at the same time in a separate
5167 ** It is intended that this variable be set once
5168 ** as part of process initialization and before any SQLite interface
5169 ** routines have been called and that this variable remain unchanged
5172 ** ^The [temp_store_directory pragma] may modify this variable and cause
5173 ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
5174 ** the [temp_store_directory pragma] always assumes that any string
5175 ** that this variable points to is held in memory obtained from
5176 ** [sqlite3_malloc] and the pragma may attempt to free that memory
5177 ** using [sqlite3_free].
5178 ** Hence, if this variable is modified directly, either it should be
5179 ** made NULL or made to point to memory obtained from [sqlite3_malloc]
5180 ** or else the use of the [temp_store_directory pragma] should be avoided.
5181 ** Except when requested by the [temp_store_directory pragma], SQLite
5182 ** does not free the memory that sqlite3_temp_directory points to. If
5183 ** the application wants that memory to be freed, it must do
5184 ** so itself, taking care to only do so after all [database connection]
5185 ** objects have been destroyed.
5187 ** <b>Note to Windows Runtime users:</b> The temporary directory must be set
5188 ** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various
5189 ** features that require the use of temporary files may fail. Here is an
5190 ** example of how to do this using C++ with the Windows Runtime:
5192 ** <blockquote><pre>
5193 ** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
5194 ** TemporaryFolder->Path->Data();
5195 ** char zPathBuf[MAX_PATH + 1];
5196 ** memset(zPathBuf, 0, sizeof(zPathBuf));
5197 ** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
5198 ** NULL, NULL);
5199 ** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
5200 ** </pre></blockquote>
5202 SQLITE_API char *sqlite3_temp_directory;
5205 ** CAPI3REF: Name Of The Folder Holding Database Files
5207 ** ^(If this global variable is made to point to a string which is
5208 ** the name of a folder (a.k.a. directory), then all database files
5209 ** specified with a relative pathname and created or accessed by
5210 ** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
5211 ** to be relative to that directory.)^ ^If this variable is a NULL
5212 ** pointer, then SQLite assumes that all database files specified
5213 ** with a relative pathname are relative to the current directory
5214 ** for the process. Only the windows VFS makes use of this global
5215 ** variable; it is ignored by the unix VFS.
5217 ** Changing the value of this variable while a database connection is
5218 ** open can result in a corrupt database.
5220 ** It is not safe to read or modify this variable in more than one
5221 ** thread at a time. It is not safe to read or modify this variable
5222 ** if a [database connection] is being used at the same time in a separate
5224 ** It is intended that this variable be set once
5225 ** as part of process initialization and before any SQLite interface
5226 ** routines have been called and that this variable remain unchanged
5229 ** ^The [data_store_directory pragma] may modify this variable and cause
5230 ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
5231 ** the [data_store_directory pragma] always assumes that any string
5232 ** that this variable points to is held in memory obtained from
5233 ** [sqlite3_malloc] and the pragma may attempt to free that memory
5234 ** using [sqlite3_free].
5235 ** Hence, if this variable is modified directly, either it should be
5236 ** made NULL or made to point to memory obtained from [sqlite3_malloc]
5237 ** or else the use of the [data_store_directory pragma] should be avoided.
5239 SQLITE_API char *sqlite3_data_directory;
5242 ** CAPI3REF: Test For Auto-Commit Mode
5243 ** KEYWORDS: {autocommit mode}
5246 ** ^The sqlite3_get_autocommit() interface returns non-zero or
5247 ** zero if the given database connection is or is not in autocommit mode,
5248 ** respectively. ^Autocommit mode is on by default.
5249 ** ^Autocommit mode is disabled by a [BEGIN] statement.
5250 ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
5252 ** If certain kinds of errors occur on a statement within a multi-statement
5253 ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
5254 ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
5255 ** transaction might be rolled back automatically. The only way to
5256 ** find out whether SQLite automatically rolled back the transaction after
5257 ** an error is to use this function.
5259 ** If another thread changes the autocommit status of the database
5260 ** connection while this routine is running, then the return value
5263 SQLITE_API int SQLITE_STDCALL sqlite3_get_autocommit(sqlite3*);
5266 ** CAPI3REF: Find The Database Handle Of A Prepared Statement
5267 ** METHOD: sqlite3_stmt
5269 ** ^The sqlite3_db_handle interface returns the [database connection] handle
5270 ** to which a [prepared statement] belongs. ^The [database connection]
5271 ** returned by sqlite3_db_handle is the same [database connection]
5272 ** that was the first argument
5273 ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
5274 ** create the statement in the first place.
5276 SQLITE_API sqlite3 *SQLITE_STDCALL sqlite3_db_handle(sqlite3_stmt*);
5279 ** CAPI3REF: Return The Filename For A Database Connection
5282 ** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
5283 ** associated with database N of connection D. ^The main database file
5284 ** has the name "main". If there is no attached database N on the database
5285 ** connection D, or if database N is a temporary or in-memory database, then
5286 ** a NULL pointer is returned.
5288 ** ^The filename returned by this function is the output of the
5289 ** xFullPathname method of the [VFS]. ^In other words, the filename
5290 ** will be an absolute pathname, even if the filename used
5291 ** to open the database originally was a URI or relative pathname.
5293 SQLITE_API const char *SQLITE_STDCALL sqlite3_db_filename(sqlite3 *db, const char *zDbName);
5296 ** CAPI3REF: Determine if a database is read-only
5299 ** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
5300 ** of connection D is read-only, 0 if it is read/write, or -1 if N is not
5301 ** the name of a database on connection D.
5303 SQLITE_API int SQLITE_STDCALL sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
5306 ** CAPI3REF: Find the next prepared statement
5309 ** ^This interface returns a pointer to the next [prepared statement] after
5310 ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
5311 ** then this interface returns a pointer to the first prepared statement
5312 ** associated with the database connection pDb. ^If no prepared statement
5313 ** satisfies the conditions of this routine, it returns NULL.
5315 ** The [database connection] pointer D in a call to
5316 ** [sqlite3_next_stmt(D,S)] must refer to an open database
5317 ** connection and in particular must not be a NULL pointer.
5319 SQLITE_API sqlite3_stmt *SQLITE_STDCALL sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
5322 ** CAPI3REF: Commit And Rollback Notification Callbacks
5325 ** ^The sqlite3_commit_hook() interface registers a callback
5326 ** function to be invoked whenever a transaction is [COMMIT | committed].
5327 ** ^Any callback set by a previous call to sqlite3_commit_hook()
5328 ** for the same database connection is overridden.
5329 ** ^The sqlite3_rollback_hook() interface registers a callback
5330 ** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
5331 ** ^Any callback set by a previous call to sqlite3_rollback_hook()
5332 ** for the same database connection is overridden.
5333 ** ^The pArg argument is passed through to the callback.
5334 ** ^If the callback on a commit hook function returns non-zero,
5335 ** then the commit is converted into a rollback.
5337 ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
5338 ** return the P argument from the previous call of the same function
5339 ** on the same [database connection] D, or NULL for
5340 ** the first call for each function on D.
5342 ** The commit and rollback hook callbacks are not reentrant.
5343 ** The callback implementation must not do anything that will modify
5344 ** the database connection that invoked the callback. Any actions
5345 ** to modify the database connection must be deferred until after the
5346 ** completion of the [sqlite3_step()] call that triggered the commit
5347 ** or rollback hook in the first place.
5348 ** Note that running any other SQL statements, including SELECT statements,
5349 ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
5350 ** the database connections for the meaning of "modify" in this paragraph.
5352 ** ^Registering a NULL function disables the callback.
5354 ** ^When the commit hook callback routine returns zero, the [COMMIT]
5355 ** operation is allowed to continue normally. ^If the commit hook
5356 ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
5357 ** ^The rollback hook is invoked on a rollback that results from a commit
5358 ** hook returning non-zero, just as it would be with any other rollback.
5360 ** ^For the purposes of this API, a transaction is said to have been
5361 ** rolled back if an explicit "ROLLBACK" statement is executed, or
5362 ** an error or constraint causes an implicit rollback to occur.
5363 ** ^The rollback callback is not invoked if a transaction is
5364 ** automatically rolled back because the database connection is closed.
5366 ** See also the [sqlite3_update_hook()] interface.
5368 SQLITE_API void *SQLITE_STDCALL sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
5369 SQLITE_API void *SQLITE_STDCALL sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
5372 ** CAPI3REF: Data Change Notification Callbacks
5375 ** ^The sqlite3_update_hook() interface registers a callback function
5376 ** with the [database connection] identified by the first argument
5377 ** to be invoked whenever a row is updated, inserted or deleted in
5379 ** ^Any callback set by a previous call to this function
5380 ** for the same database connection is overridden.
5382 ** ^The second argument is a pointer to the function to invoke when a
5383 ** row is updated, inserted or deleted in a rowid table.
5384 ** ^The first argument to the callback is a copy of the third argument
5385 ** to sqlite3_update_hook().
5386 ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
5387 ** or [SQLITE_UPDATE], depending on the operation that caused the callback
5389 ** ^The third and fourth arguments to the callback contain pointers to the
5390 ** database and table name containing the affected row.
5391 ** ^The final callback parameter is the [rowid] of the row.
5392 ** ^In the case of an update, this is the [rowid] after the update takes place.
5394 ** ^(The update hook is not invoked when internal system tables are
5395 ** modified (i.e. sqlite_master and sqlite_sequence).)^
5396 ** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
5398 ** ^In the current implementation, the update hook
5399 ** is not invoked when duplication rows are deleted because of an
5400 ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
5401 ** invoked when rows are deleted using the [truncate optimization].
5402 ** The exceptions defined in this paragraph might change in a future
5403 ** release of SQLite.
5405 ** The update hook implementation must not do anything that will modify
5406 ** the database connection that invoked the update hook. Any actions
5407 ** to modify the database connection must be deferred until after the
5408 ** completion of the [sqlite3_step()] call that triggered the update hook.
5409 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
5410 ** database connections for the meaning of "modify" in this paragraph.
5412 ** ^The sqlite3_update_hook(D,C,P) function
5413 ** returns the P argument from the previous call
5414 ** on the same [database connection] D, or NULL for
5415 ** the first call on D.
5417 ** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
5420 SQLITE_API void *SQLITE_STDCALL sqlite3_update_hook(
5422 void(*)(void *,int ,char const *,char const *,sqlite3_int64),
5427 ** CAPI3REF: Enable Or Disable Shared Pager Cache
5429 ** ^(This routine enables or disables the sharing of the database cache
5430 ** and schema data structures between [database connection | connections]
5431 ** to the same database. Sharing is enabled if the argument is true
5432 ** and disabled if the argument is false.)^
5434 ** ^Cache sharing is enabled and disabled for an entire process.
5435 ** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
5436 ** sharing was enabled or disabled for each thread separately.
5438 ** ^(The cache sharing mode set by this interface effects all subsequent
5439 ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
5440 ** Existing database connections continue use the sharing mode
5441 ** that was in effect at the time they were opened.)^
5443 ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
5444 ** successfully. An [error code] is returned otherwise.)^
5446 ** ^Shared cache is disabled by default. But this might change in
5447 ** future releases of SQLite. Applications that care about shared
5448 ** cache setting should set it explicitly.
5450 ** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0
5451 ** and will always return SQLITE_MISUSE. On those systems,
5452 ** shared cache mode should be enabled per-database connection via
5453 ** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE].
5455 ** This interface is threadsafe on processors where writing a
5456 ** 32-bit integer is atomic.
5458 ** See Also: [SQLite Shared-Cache Mode]
5460 SQLITE_API int SQLITE_STDCALL sqlite3_enable_shared_cache(int);
5463 ** CAPI3REF: Attempt To Free Heap Memory
5465 ** ^The sqlite3_release_memory() interface attempts to free N bytes
5466 ** of heap memory by deallocating non-essential memory allocations
5467 ** held by the database library. Memory used to cache database
5468 ** pages to improve performance is an example of non-essential memory.
5469 ** ^sqlite3_release_memory() returns the number of bytes actually freed,
5470 ** which might be more or less than the amount requested.
5471 ** ^The sqlite3_release_memory() routine is a no-op returning zero
5472 ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
5474 ** See also: [sqlite3_db_release_memory()]
5476 SQLITE_API int SQLITE_STDCALL sqlite3_release_memory(int);
5479 ** CAPI3REF: Free Memory Used By A Database Connection
5482 ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
5483 ** memory as possible from database connection D. Unlike the
5484 ** [sqlite3_release_memory()] interface, this interface is in effect even
5485 ** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
5488 ** See also: [sqlite3_release_memory()]
5490 SQLITE_API int SQLITE_STDCALL sqlite3_db_release_memory(sqlite3*);
5493 ** CAPI3REF: Impose A Limit On Heap Size
5495 ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
5496 ** soft limit on the amount of heap memory that may be allocated by SQLite.
5497 ** ^SQLite strives to keep heap memory utilization below the soft heap
5498 ** limit by reducing the number of pages held in the page cache
5499 ** as heap memory usages approaches the limit.
5500 ** ^The soft heap limit is "soft" because even though SQLite strives to stay
5501 ** below the limit, it will exceed the limit rather than generate
5502 ** an [SQLITE_NOMEM] error. In other words, the soft heap limit
5503 ** is advisory only.
5505 ** ^The return value from sqlite3_soft_heap_limit64() is the size of
5506 ** the soft heap limit prior to the call, or negative in the case of an
5507 ** error. ^If the argument N is negative
5508 ** then no change is made to the soft heap limit. Hence, the current
5509 ** size of the soft heap limit can be determined by invoking
5510 ** sqlite3_soft_heap_limit64() with a negative argument.
5512 ** ^If the argument N is zero then the soft heap limit is disabled.
5514 ** ^(The soft heap limit is not enforced in the current implementation
5515 ** if one or more of following conditions are true:
5518 ** <li> The soft heap limit is set to zero.
5519 ** <li> Memory accounting is disabled using a combination of the
5520 ** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
5521 ** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
5522 ** <li> An alternative page cache implementation is specified using
5523 ** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
5524 ** <li> The page cache allocates from its own memory pool supplied
5525 ** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
5529 ** Beginning with SQLite version 3.7.3, the soft heap limit is enforced
5530 ** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
5531 ** compile-time option is invoked. With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
5532 ** the soft heap limit is enforced on every memory allocation. Without
5533 ** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
5534 ** when memory is allocated by the page cache. Testing suggests that because
5535 ** the page cache is the predominate memory user in SQLite, most
5536 ** applications will achieve adequate soft heap limit enforcement without
5537 ** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
5539 ** The circumstances under which SQLite will enforce the soft heap limit may
5540 ** changes in future releases of SQLite.
5542 SQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_soft_heap_limit64(sqlite3_int64 N);
5545 ** CAPI3REF: Deprecated Soft Heap Limit Interface
5548 ** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
5549 ** interface. This routine is provided for historical compatibility
5550 ** only. All new applications should use the
5551 ** [sqlite3_soft_heap_limit64()] interface rather than this one.
5553 SQLITE_API SQLITE_DEPRECATED void SQLITE_STDCALL sqlite3_soft_heap_limit(int N);
5557 ** CAPI3REF: Extract Metadata About A Column Of A Table
5560 ** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns
5561 ** information about column C of table T in database D
5562 ** on [database connection] X.)^ ^The sqlite3_table_column_metadata()
5563 ** interface returns SQLITE_OK and fills in the non-NULL pointers in
5564 ** the final five arguments with appropriate values if the specified
5565 ** column exists. ^The sqlite3_table_column_metadata() interface returns
5566 ** SQLITE_ERROR and if the specified column does not exist.
5567 ** ^If the column-name parameter to sqlite3_table_column_metadata() is a
5568 ** NULL pointer, then this routine simply checks for the existance of the
5569 ** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it
5572 ** ^The column is identified by the second, third and fourth parameters to
5573 ** this function. ^(The second parameter is either the name of the database
5574 ** (i.e. "main", "temp", or an attached database) containing the specified
5575 ** table or NULL.)^ ^If it is NULL, then all attached databases are searched
5576 ** for the table using the same algorithm used by the database engine to
5577 ** resolve unqualified table references.
5579 ** ^The third and fourth parameters to this function are the table and column
5580 ** name of the desired column, respectively.
5582 ** ^Metadata is returned by writing to the memory locations passed as the 5th
5583 ** and subsequent parameters to this function. ^Any of these arguments may be
5584 ** NULL, in which case the corresponding element of metadata is omitted.
5587 ** <table border="1">
5588 ** <tr><th> Parameter <th> Output<br>Type <th> Description
5590 ** <tr><td> 5th <td> const char* <td> Data type
5591 ** <tr><td> 6th <td> const char* <td> Name of default collation sequence
5592 ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
5593 ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
5594 ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
5598 ** ^The memory pointed to by the character pointers returned for the
5599 ** declaration type and collation sequence is valid until the next
5600 ** call to any SQLite API function.
5602 ** ^If the specified table is actually a view, an [error code] is returned.
5604 ** ^If the specified column is "rowid", "oid" or "_rowid_" and the table
5605 ** is not a [WITHOUT ROWID] table and an
5606 ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
5607 ** parameters are set for the explicitly declared column. ^(If there is no
5608 ** [INTEGER PRIMARY KEY] column, then the outputs
5609 ** for the [rowid] are set as follows:
5612 ** data type: "INTEGER"
5613 ** collation sequence: "BINARY"
5616 ** auto increment: 0
5619 ** ^This function causes all database schemas to be read from disk and
5620 ** parsed, if that has not already been done, and returns an error if
5621 ** any errors are encountered while loading the schema.
5623 SQLITE_API int SQLITE_STDCALL sqlite3_table_column_metadata(
5624 sqlite3 *db, /* Connection handle */
5625 const char *zDbName, /* Database name or NULL */
5626 const char *zTableName, /* Table name */
5627 const char *zColumnName, /* Column name */
5628 char const **pzDataType, /* OUTPUT: Declared data type */
5629 char const **pzCollSeq, /* OUTPUT: Collation sequence name */
5630 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
5631 int *pPrimaryKey, /* OUTPUT: True if column part of PK */
5632 int *pAutoinc /* OUTPUT: True if column is auto-increment */
5636 ** CAPI3REF: Load An Extension
5639 ** ^This interface loads an SQLite extension library from the named file.
5641 ** ^The sqlite3_load_extension() interface attempts to load an
5642 ** [SQLite extension] library contained in the file zFile. If
5643 ** the file cannot be loaded directly, attempts are made to load
5644 ** with various operating-system specific extensions added.
5645 ** So for example, if "samplelib" cannot be loaded, then names like
5646 ** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
5649 ** ^The entry point is zProc.
5650 ** ^(zProc may be 0, in which case SQLite will try to come up with an
5651 ** entry point name on its own. It first tries "sqlite3_extension_init".
5652 ** If that does not work, it constructs a name "sqlite3_X_init" where the
5653 ** X is consists of the lower-case equivalent of all ASCII alphabetic
5654 ** characters in the filename from the last "/" to the first following
5655 ** "." and omitting any initial "lib".)^
5656 ** ^The sqlite3_load_extension() interface returns
5657 ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
5658 ** ^If an error occurs and pzErrMsg is not 0, then the
5659 ** [sqlite3_load_extension()] interface shall attempt to
5660 ** fill *pzErrMsg with error message text stored in memory
5661 ** obtained from [sqlite3_malloc()]. The calling function
5662 ** should free this memory by calling [sqlite3_free()].
5664 ** ^Extension loading must be enabled using
5665 ** [sqlite3_enable_load_extension()] prior to calling this API,
5666 ** otherwise an error will be returned.
5668 ** See also the [load_extension() SQL function].
5670 SQLITE_API int SQLITE_STDCALL sqlite3_load_extension(
5671 sqlite3 *db, /* Load the extension into this database connection */
5672 const char *zFile, /* Name of the shared library containing extension */
5673 const char *zProc, /* Entry point. Derived from zFile if 0 */
5674 char **pzErrMsg /* Put error message here if not 0 */
5678 ** CAPI3REF: Enable Or Disable Extension Loading
5681 ** ^So as not to open security holes in older applications that are
5682 ** unprepared to deal with [extension loading], and as a means of disabling
5683 ** [extension loading] while evaluating user-entered SQL, the following API
5684 ** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
5686 ** ^Extension loading is off by default.
5687 ** ^Call the sqlite3_enable_load_extension() routine with onoff==1
5688 ** to turn extension loading on and call it with onoff==0 to turn
5689 ** it back off again.
5691 SQLITE_API int SQLITE_STDCALL sqlite3_enable_load_extension(sqlite3 *db, int onoff);
5694 ** CAPI3REF: Automatically Load Statically Linked Extensions
5696 ** ^This interface causes the xEntryPoint() function to be invoked for
5697 ** each new [database connection] that is created. The idea here is that
5698 ** xEntryPoint() is the entry point for a statically linked [SQLite extension]
5699 ** that is to be automatically loaded into all new database connections.
5701 ** ^(Even though the function prototype shows that xEntryPoint() takes
5702 ** no arguments and returns void, SQLite invokes xEntryPoint() with three
5703 ** arguments and expects and integer result as if the signature of the
5704 ** entry point where as follows:
5706 ** <blockquote><pre>
5707 ** int xEntryPoint(
5708 ** sqlite3 *db,
5709 ** const char **pzErrMsg,
5710 ** const struct sqlite3_api_routines *pThunk
5712 ** </pre></blockquote>)^
5714 ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
5715 ** point to an appropriate error message (obtained from [sqlite3_mprintf()])
5716 ** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg
5717 ** is NULL before calling the xEntryPoint(). ^SQLite will invoke
5718 ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any
5719 ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
5720 ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
5722 ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
5723 ** on the list of automatic extensions is a harmless no-op. ^No entry point
5724 ** will be called more than once for each database connection that is opened.
5726 ** See also: [sqlite3_reset_auto_extension()]
5727 ** and [sqlite3_cancel_auto_extension()]
5729 SQLITE_API int SQLITE_STDCALL sqlite3_auto_extension(void (*xEntryPoint)(void));
5732 ** CAPI3REF: Cancel Automatic Extension Loading
5734 ** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
5735 ** initialization routine X that was registered using a prior call to
5736 ** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)]
5737 ** routine returns 1 if initialization routine X was successfully
5738 ** unregistered and it returns 0 if X was not on the list of initialization
5741 SQLITE_API int SQLITE_STDCALL sqlite3_cancel_auto_extension(void (*xEntryPoint)(void));
5744 ** CAPI3REF: Reset Automatic Extension Loading
5746 ** ^This interface disables all automatic extensions previously
5747 ** registered using [sqlite3_auto_extension()].
5749 SQLITE_API void SQLITE_STDCALL sqlite3_reset_auto_extension(void);
5752 ** The interface to the virtual-table mechanism is currently considered
5753 ** to be experimental. The interface might change in incompatible ways.
5754 ** If this is a problem for you, do not use the interface at this time.
5756 ** When the virtual-table mechanism stabilizes, we will declare the
5757 ** interface fixed, support it indefinitely, and remove this comment.
5761 ** Structures used by the virtual table interface
5763 typedef struct sqlite3_vtab sqlite3_vtab;
5764 typedef struct sqlite3_index_info sqlite3_index_info;
5765 typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
5766 typedef struct sqlite3_module sqlite3_module;
5769 ** CAPI3REF: Virtual Table Object
5770 ** KEYWORDS: sqlite3_module {virtual table module}
5772 ** This structure, sometimes called a "virtual table module",
5773 ** defines the implementation of a [virtual tables].
5774 ** This structure consists mostly of methods for the module.
5776 ** ^A virtual table module is created by filling in a persistent
5777 ** instance of this structure and passing a pointer to that instance
5778 ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
5779 ** ^The registration remains valid until it is replaced by a different
5780 ** module or until the [database connection] closes. The content
5781 ** of this structure must not change while it is registered with
5782 ** any database connection.
5784 struct sqlite3_module {
5786 int (*xCreate)(sqlite3*, void *pAux,
5787 int argc, const char *const*argv,
5788 sqlite3_vtab **ppVTab, char**);
5789 int (*xConnect)(sqlite3*, void *pAux,
5790 int argc, const char *const*argv,
5791 sqlite3_vtab **ppVTab, char**);
5792 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
5793 int (*xDisconnect)(sqlite3_vtab *pVTab);
5794 int (*xDestroy)(sqlite3_vtab *pVTab);
5795 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
5796 int (*xClose)(sqlite3_vtab_cursor*);
5797 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
5798 int argc, sqlite3_value **argv);
5799 int (*xNext)(sqlite3_vtab_cursor*);
5800 int (*xEof)(sqlite3_vtab_cursor*);
5801 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
5802 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
5803 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
5804 int (*xBegin)(sqlite3_vtab *pVTab);
5805 int (*xSync)(sqlite3_vtab *pVTab);
5806 int (*xCommit)(sqlite3_vtab *pVTab);
5807 int (*xRollback)(sqlite3_vtab *pVTab);
5808 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
5809 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
5811 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
5812 /* The methods above are in version 1 of the sqlite_module object. Those
5813 ** below are for version 2 and greater. */
5814 int (*xSavepoint)(sqlite3_vtab *pVTab, int);
5815 int (*xRelease)(sqlite3_vtab *pVTab, int);
5816 int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
5820 ** CAPI3REF: Virtual Table Indexing Information
5821 ** KEYWORDS: sqlite3_index_info
5823 ** The sqlite3_index_info structure and its substructures is used as part
5824 ** of the [virtual table] interface to
5825 ** pass information into and receive the reply from the [xBestIndex]
5826 ** method of a [virtual table module]. The fields under **Inputs** are the
5827 ** inputs to xBestIndex and are read-only. xBestIndex inserts its
5828 ** results into the **Outputs** fields.
5830 ** ^(The aConstraint[] array records WHERE clause constraints of the form:
5832 ** <blockquote>column OP expr</blockquote>
5834 ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is
5835 ** stored in aConstraint[].op using one of the
5836 ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
5837 ** ^(The index of the column is stored in
5838 ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
5839 ** expr on the right-hand side can be evaluated (and thus the constraint
5840 ** is usable) and false if it cannot.)^
5842 ** ^The optimizer automatically inverts terms of the form "expr OP column"
5843 ** and makes other simplifications to the WHERE clause in an attempt to
5844 ** get as many WHERE clause terms into the form shown above as possible.
5845 ** ^The aConstraint[] array only reports WHERE clause terms that are
5846 ** relevant to the particular virtual table being queried.
5848 ** ^Information about the ORDER BY clause is stored in aOrderBy[].
5849 ** ^Each term of aOrderBy records a column of the ORDER BY clause.
5851 ** The colUsed field indicates which columns of the virtual table may be
5852 ** required by the current scan. Virtual table columns are numbered from
5853 ** zero in the order in which they appear within the CREATE TABLE statement
5854 ** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62),
5855 ** the corresponding bit is set within the colUsed mask if the column may be
5856 ** required by SQLite. If the table has at least 64 columns and any column
5857 ** to the right of the first 63 is required, then bit 63 of colUsed is also
5858 ** set. In other words, column iCol may be required if the expression
5859 ** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to
5862 ** The [xBestIndex] method must fill aConstraintUsage[] with information
5863 ** about what parameters to pass to xFilter. ^If argvIndex>0 then
5864 ** the right-hand side of the corresponding aConstraint[] is evaluated
5865 ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
5866 ** is true, then the constraint is assumed to be fully handled by the
5867 ** virtual table and is not checked again by SQLite.)^
5869 ** ^The idxNum and idxPtr values are recorded and passed into the
5870 ** [xFilter] method.
5871 ** ^[sqlite3_free()] is used to free idxPtr if and only if
5872 ** needToFreeIdxPtr is true.
5874 ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
5875 ** the correct order to satisfy the ORDER BY clause so that no separate
5876 ** sorting step is required.
5878 ** ^The estimatedCost value is an estimate of the cost of a particular
5879 ** strategy. A cost of N indicates that the cost of the strategy is similar
5880 ** to a linear scan of an SQLite table with N rows. A cost of log(N)
5881 ** indicates that the expense of the operation is similar to that of a
5882 ** binary search on a unique indexed field of an SQLite table with N rows.
5884 ** ^The estimatedRows value is an estimate of the number of rows that
5885 ** will be returned by the strategy.
5887 ** The xBestIndex method may optionally populate the idxFlags field with a
5888 ** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag -
5889 ** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite
5890 ** assumes that the strategy may visit at most one row.
5892 ** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then
5893 ** SQLite also assumes that if a call to the xUpdate() method is made as
5894 ** part of the same statement to delete or update a virtual table row and the
5895 ** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback
5896 ** any database changes. In other words, if the xUpdate() returns
5897 ** SQLITE_CONSTRAINT, the database contents must be exactly as they were
5898 ** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not
5899 ** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by
5900 ** the xUpdate method are automatically rolled back by SQLite.
5902 ** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
5903 ** structure for SQLite version 3.8.2. If a virtual table extension is
5904 ** used with an SQLite version earlier than 3.8.2, the results of attempting
5905 ** to read or write the estimatedRows field are undefined (but are likely
5906 ** to included crashing the application). The estimatedRows field should
5907 ** therefore only be used if [sqlite3_libversion_number()] returns a
5908 ** value greater than or equal to 3008002. Similarly, the idxFlags field
5909 ** was added for version 3.9.0. It may therefore only be used if
5910 ** sqlite3_libversion_number() returns a value greater than or equal to
5913 struct sqlite3_index_info {
5915 int nConstraint; /* Number of entries in aConstraint */
5916 struct sqlite3_index_constraint {
5917 int iColumn; /* Column constrained. -1 for ROWID */
5918 unsigned char op; /* Constraint operator */
5919 unsigned char usable; /* True if this constraint is usable */
5920 int iTermOffset; /* Used internally - xBestIndex should ignore */
5921 } *aConstraint; /* Table of WHERE clause constraints */
5922 int nOrderBy; /* Number of terms in the ORDER BY clause */
5923 struct sqlite3_index_orderby {
5924 int iColumn; /* Column number */
5925 unsigned char desc; /* True for DESC. False for ASC. */
5926 } *aOrderBy; /* The ORDER BY clause */
5928 struct sqlite3_index_constraint_usage {
5929 int argvIndex; /* if >0, constraint is part of argv to xFilter */
5930 unsigned char omit; /* Do not code a test for this constraint */
5931 } *aConstraintUsage;
5932 int idxNum; /* Number used to identify the index */
5933 char *idxStr; /* String, possibly obtained from sqlite3_malloc */
5934 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
5935 int orderByConsumed; /* True if output is already ordered */
5936 double estimatedCost; /* Estimated cost of using this index */
5937 /* Fields below are only available in SQLite 3.8.2 and later */
5938 sqlite3_int64 estimatedRows; /* Estimated number of rows returned */
5939 /* Fields below are only available in SQLite 3.9.0 and later */
5940 int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */
5941 /* Fields below are only available in SQLite 3.10.0 and later */
5942 sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */
5946 ** CAPI3REF: Virtual Table Scan Flags
5948 #define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */
5951 ** CAPI3REF: Virtual Table Constraint Operator Codes
5953 ** These macros defined the allowed values for the
5954 ** [sqlite3_index_info].aConstraint[].op field. Each value represents
5955 ** an operator that is part of a constraint term in the wHERE clause of
5956 ** a query that uses a [virtual table].
5958 #define SQLITE_INDEX_CONSTRAINT_EQ 2
5959 #define SQLITE_INDEX_CONSTRAINT_GT 4
5960 #define SQLITE_INDEX_CONSTRAINT_LE 8
5961 #define SQLITE_INDEX_CONSTRAINT_LT 16
5962 #define SQLITE_INDEX_CONSTRAINT_GE 32
5963 #define SQLITE_INDEX_CONSTRAINT_MATCH 64
5964 #define SQLITE_INDEX_CONSTRAINT_LIKE 65
5965 #define SQLITE_INDEX_CONSTRAINT_GLOB 66
5966 #define SQLITE_INDEX_CONSTRAINT_REGEXP 67
5969 ** CAPI3REF: Register A Virtual Table Implementation
5972 ** ^These routines are used to register a new [virtual table module] name.
5973 ** ^Module names must be registered before
5974 ** creating a new [virtual table] using the module and before using a
5975 ** preexisting [virtual table] for the module.
5977 ** ^The module name is registered on the [database connection] specified
5978 ** by the first parameter. ^The name of the module is given by the
5979 ** second parameter. ^The third parameter is a pointer to
5980 ** the implementation of the [virtual table module]. ^The fourth
5981 ** parameter is an arbitrary client data pointer that is passed through
5982 ** into the [xCreate] and [xConnect] methods of the virtual table module
5983 ** when a new virtual table is be being created or reinitialized.
5985 ** ^The sqlite3_create_module_v2() interface has a fifth parameter which
5986 ** is a pointer to a destructor for the pClientData. ^SQLite will
5987 ** invoke the destructor function (if it is not NULL) when SQLite
5988 ** no longer needs the pClientData pointer. ^The destructor will also
5989 ** be invoked if the call to sqlite3_create_module_v2() fails.
5990 ** ^The sqlite3_create_module()
5991 ** interface is equivalent to sqlite3_create_module_v2() with a NULL
5994 SQLITE_API int SQLITE_STDCALL sqlite3_create_module(
5995 sqlite3 *db, /* SQLite connection to register module with */
5996 const char *zName, /* Name of the module */
5997 const sqlite3_module *p, /* Methods for the module */
5998 void *pClientData /* Client data for xCreate/xConnect */
6000 SQLITE_API int SQLITE_STDCALL sqlite3_create_module_v2(
6001 sqlite3 *db, /* SQLite connection to register module with */
6002 const char *zName, /* Name of the module */
6003 const sqlite3_module *p, /* Methods for the module */
6004 void *pClientData, /* Client data for xCreate/xConnect */
6005 void(*xDestroy)(void*) /* Module destru