sqlite3.h

sqlite 嵌入式数据库的源码

/*
** 2001 September 15
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This header file defines the interface that the SQLite library
** presents to client programs.
**
** @(#) $Id: sqlite.h.in,v 1.136 2005/06/12 22:12:39 drh Exp $
*/
#ifndef _SQLITE3_H_
#define _SQLITE3_H_
#include <stdarg.h>     /* Needed for the definition of va_list */

/*
** Make sure we can call this stuff from C++.
*/
#ifdef __cplusplus
extern "C" {
#endif

/*
** The version of the SQLite library.
*/
#ifdef SQLITE_VERSION
# undef SQLITE_VERSION
#endif
#define SQLITE_VERSION         "3.2.2"

/*
** The format of the version string is "X.Y.Z<trailing string>", where
** X is the major version number, Y is the minor version number and Z
** is the release number. The trailing string is often "alpha" or "beta".
** For example "3.1.1beta".
**
** The SQLITE_VERSION_NUMBER is an integer with the value 
** (X*100000 + Y*1000 + Z). For example, for version "3.1.1beta", 
** SQLITE_VERSION_NUMBER is set to 3001001. To detect if they are using 
** version 3.1.1 or greater at compile time, programs may use the test 
** (SQLITE_VERSION_NUMBER>=3001001).
*/
#ifdef SQLITE_VERSION_NUMBER
# undef SQLITE_VERSION_NUMBER
#endif
#define SQLITE_VERSION_NUMBER 3002002

/*
** The version string is also compiled into the library so that a program
** can check to make sure that the lib*.a file and the *.h file are from
** the same version.  The sqlite3_libversion() function returns a pointer
** to the sqlite3_version variable - useful in DLLs which cannot access
** global variables.
*/
extern const char sqlite3_version[];
const char *sqlite3_libversion(void);

/*
** Return the value of the SQLITE_VERSION_NUMBER macro when the
** library was compiled.
*/
int sqlite3_libversion_number(void);

/*
** Each open sqlite database is represented by an instance of the
** following opaque structure.
*/
typedef struct sqlite3 sqlite3;


/*
** Some compilers do not support the "long long" datatype.  So we have
** to do a typedef that for 64-bit integers that depends on what compiler
** is being used.
*/
#if defined(_MSC_VER) || defined(__BORLANDC__)
  typedef __int64 sqlite_int64;
  typedef unsigned __int64 sqlite_uint64;
#else
  typedef long long int sqlite_int64;
  typedef unsigned long long int sqlite_uint64;
#endif


/*
** A function to close the database.
**
** Call this function with a pointer to a structure that was previously
** returned from sqlite3_open() and the corresponding database will by closed.
**
** All SQL statements prepared using sqlite3_prepare() or
** sqlite3_prepare16() must be deallocated using sqlite3_finalize() before
** this routine is called. Otherwise, SQLITE_BUSY is returned and the
** database connection remains open.
*/
int sqlite3_close(sqlite3 *);

/*
** The type for a callback function.
*/
typedef int (*sqlite3_callback)(void*,int,char**, char**);

/*
** A function to executes one or more statements of SQL.
**
** If one or more of the SQL statements are queries, then
** the callback function specified by the 3rd parameter is
** invoked once for each row of the query result.  This callback
** should normally return 0.  If the callback returns a non-zero
** value then the query is aborted, all subsequent SQL statements
** are skipped and the sqlite3_exec() function returns the SQLITE_ABORT.
**
** The 4th parameter is an arbitrary pointer that is passed
** to the callback function as its first parameter.
**
** The 2nd parameter to the callback function is the number of
** columns in the query result.  The 3rd parameter to the callback
** is an array of strings holding the values for each column.
** The 4th parameter to the callback is an array of strings holding
** the names of each column.
**
** The callback function may be NULL, even for queries.  A NULL
** callback is not an error.  It just means that no callback
** will be invoked.
**
** If an error occurs while parsing or evaluating the SQL (but
** not while executing the callback) then an appropriate error
** message is written into memory obtained from malloc() and
** *errmsg is made to point to that message.  The calling function
** is responsible for freeing the memory that holds the error
** message.   Use sqlite3_free() for this.  If errmsg==NULL,
** then no error message is ever written.
**
** The return value is is SQLITE_OK if there are no errors and
** some other return code if there is an error.  The particular
** return value depends on the type of error. 
**
** If the query could not be executed because a database file is
** locked or busy, then this function returns SQLITE_BUSY.  (This
** behavior can be modified somewhat using the sqlite3_busy_handler()
** and sqlite3_busy_timeout() functions below.)
*/
int sqlite3_exec(
  sqlite3*,                     /* An open database */
  const char *sql,              /* SQL to be executed */
  sqlite3_callback,             /* Callback function */
  void *,                       /* 1st argument to callback function */
  char **errmsg                 /* Error msg written here */
);

/*
** Return values for sqlite3_exec() and sqlite3_step()
*/
#define SQLITE_OK           0   /* Successful result */
#define SQLITE_ERROR        1   /* SQL error or missing database */
#define SQLITE_INTERNAL     2   /* An internal logic error in SQLite */
#define SQLITE_PERM         3   /* Access permission denied */
#define SQLITE_ABORT        4   /* Callback routine requested an abort */
#define SQLITE_BUSY         5   /* The database file is locked */
#define SQLITE_LOCKED       6   /* A table in the database is locked */
#define SQLITE_NOMEM        7   /* A malloc() failed */
#define SQLITE_READONLY     8   /* Attempt to write a readonly database */
#define SQLITE_INTERRUPT    9   /* Operation terminated by sqlite3_interrupt()*/
#define SQLITE_IOERR       10   /* Some kind of disk I/O error occurred */
#define SQLITE_CORRUPT     11   /* The database disk image is malformed */
#define SQLITE_NOTFOUND    12   /* (Internal Only) Table or record not found */
#define SQLITE_FULL        13   /* Insertion failed because database is full */
#define SQLITE_CANTOPEN    14   /* Unable to open the database file */
#define SQLITE_PROTOCOL    15   /* Database lock protocol error */
#define SQLITE_EMPTY       16   /* Database is empty */
#define SQLITE_SCHEMA      17   /* The database schema changed */
#define SQLITE_TOOBIG      18   /* Too much data for one row of a table */
#define SQLITE_CONSTRAINT  19   /* Abort due to contraint violation */
#define SQLITE_MISMATCH    20   /* Data type mismatch */
#define SQLITE_MISUSE      21   /* Library used incorrectly */
#define SQLITE_NOLFS       22   /* Uses OS features not supported on host */
#define SQLITE_AUTH        23   /* Authorization denied */
#define SQLITE_FORMAT      24   /* Auxiliary database format error */
#define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
#define SQLITE_NOTADB      26   /* File opened that is not a database file */
#define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
#define SQLITE_DONE        101  /* sqlite3_step() has finished executing */

/*
** Each entry in an SQLite table has a unique integer key.  (The key is
** the value of the INTEGER PRIMARY KEY column if there is such a column,
** otherwise the key is generated at random.  The unique key is always
** available as the ROWID, OID, or _ROWID_ column.)  The following routine
** returns the integer key of the most recent insert in the database.
**
** This function is similar to the mysql_insert_id() function from MySQL.
*/
sqlite_int64 sqlite3_last_insert_rowid(sqlite3*);

/*
** This function returns the number of database rows that were changed
** (or inserted or deleted) by the most recent called sqlite3_exec().
**
** All changes are counted, even if they were later undone by a
** ROLLBACK or ABORT.  Except, changes associated with creating and
** dropping tables are not counted.
**
** If a callback invokes sqlite3_exec() recursively, then the changes
** in the inner, recursive call are counted together with the changes
** in the outer call.
**
** SQLite implements the command "DELETE FROM table" without a WHERE clause
** by dropping and recreating the table.  (This is much faster than going
** through and deleting individual elements form the table.)  Because of
** this optimization, the change count for "DELETE FROM table" will be
** zero regardless of the number of elements that were originally in the
** table. To get an accurate count of the number of rows deleted, use
** "DELETE FROM table WHERE 1" instead.
*/
int sqlite3_changes(sqlite3*);

/*
** This function returns the number of database rows that have been
** modified by INSERT, UPDATE or DELETE statements since the database handle
** was opened. This includes UPDATE, INSERT and DELETE statements executed
** as part of trigger programs. All changes are counted as soon as the
** statement that makes them is completed (when the statement handle is
** passed to sqlite3_reset() or sqlite_finalise()).
**
** SQLite implements the command "DELETE FROM table" without a WHERE clause
** by dropping and recreating the table.  (This is much faster than going
** through and deleting individual elements form the table.)  Because of
** this optimization, the change count for "DELETE FROM table" will be
** zero regardless of the number of elements that were originally in the
** table. To get an accurate count of the number of rows deleted, use
** "DELETE FROM table WHERE 1" instead.
*/
int sqlite3_total_changes(sqlite3*);

/* This function causes any pending database operation to abort and
** return at its earliest opportunity.  This routine is typically
** called in response to a user action such as pressing "Cancel"
** or Ctrl-C where the user wants a long query operation to halt
** immediately.
*/
void sqlite3_interrupt(sqlite3*);


/* These functions return true if the given input string comprises
** one or more complete SQL statements. For the sqlite3_complete() call,
** the parameter must be a nul-terminated UTF-8 string. For
** sqlite3_complete16(), a nul-terminated machine byte order UTF-16 string
** is required.
**
** The algorithm is simple.  If the last token other than spaces
** and comments is a semicolon, then return true.  otherwise return
** false.
*/
int sqlite3_complete(const char *sql);
int sqlite3_complete16(const void *sql);

/*
** This routine identifies a callback function that is invoked
** whenever an attempt is made to open a database table that is
** currently locked by another process or thread.  If the busy callback
** is NULL, then sqlite3_exec() returns SQLITE_BUSY immediately if
** it finds a locked table.  If the busy callback is not NULL, then
** sqlite3_exec() invokes the callback with three arguments.  The
** second argument is the name of the locked table and the third
** argument is the number of times the table has been busy.  If the
** busy callback returns 0, then sqlite3_exec() immediately returns
** SQLITE_BUSY.  If the callback returns non-zero, then sqlite3_exec()
** tries to open the table again and the cycle repeats.
**
** The default busy callback is NULL.
**
** Sqlite is re-entrant, so the busy handler may start a new query. 
** (It is not clear why anyone would every want to do this, but it
** is allowed, in theory.)  But the busy handler may not close the
** database.  Closing the database from a busy handler will delete 
** data structures out from under the executing query and will 
** probably result in a coredump.
*/
int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);

/*
** This routine sets a busy handler that sleeps for a while when a
** table is locked.  The handler will sleep multiple times until 
** at least "ms" milleseconds of sleeping have been done.  After
** "ms" milleseconds of sleeping, the handler returns 0 which
** causes sqlite3_exec() to return SQLITE_BUSY.
**
** Calling this routine with an argument less than or equal to zero
** turns off all busy handlers.
*/
int sqlite3_busy_timeout(sqlite3*, int ms);

/*
** This next routine is really just a wrapper around sqlite3_exec().
** Instead of invoking a user-supplied callback for each row of the
** result, this routine remembers each row of the result in memory
** obtained from malloc(), then returns all of the result after the
** query has finished. 
**
** As an example, suppose the query result where this table:
**
**        Name        | Age
**        -----------------------
**        Alice       | 43
**        Bob         | 28
**        Cindy       | 21
**
** If the 3rd argument were &azResult then after the function returns
** azResult will contain the following data:
**
**        azResult[0] = "Name";
**        azResult[1] = "Age";