sqlite3.h

sqlite 嵌入式数据库的源码

**        azResult[2] = "Alice";
**        azResult[3] = "43";
**        azResult[4] = "Bob";
**        azResult[5] = "28";
**        azResult[6] = "Cindy";
**        azResult[7] = "21";
**
** Notice that there is an extra row of data containing the column
** headers.  But the *nrow return value is still 3.  *ncolumn is
** set to 2.  In general, the number of values inserted into azResult
** will be ((*nrow) + 1)*(*ncolumn).
**
** After the calling function has finished using the result, it should 
** pass the result data pointer to sqlite3_free_table() in order to 
** release the memory that was malloc-ed.  Because of the way the 
** malloc() happens, the calling function must not try to call 
** free() directly.  Only sqlite3_free_table() is able to release 
** the memory properly and safely.
**
** The return value of this routine is the same as from sqlite3_exec().
*/
int sqlite3_get_table(
  sqlite3*,               /* An open database */
  const char *sql,       /* SQL to be executed */
  char ***resultp,       /* Result written to a char *[]  that this points to */
  int *nrow,             /* Number of result rows written here */
  int *ncolumn,          /* Number of result columns written here */
  char **errmsg          /* Error msg written here */
);

/*
** Call this routine to free the memory that sqlite3_get_table() allocated.
*/
void sqlite3_free_table(char **result);

/*
** The following routines are variants of the "sprintf()" from the
** standard C library.  The resulting string is written into memory
** obtained from malloc() so that there is never a possiblity of buffer
** overflow.  These routines also implement some additional formatting
** options that are useful for constructing SQL statements.
**
** The strings returned by these routines should be freed by calling
** sqlite3_free().
**
** All of the usual printf formatting options apply.  In addition, there
** is a "%q" option.  %q works like %s in that it substitutes a null-terminated
** string from the argument list.  But %q also doubles every '\'' character.
** %q is designed for use inside a string literal.  By doubling each '\''
** character it escapes that character and allows it to be inserted into
** the string.
**
** For example, so some string variable contains text as follows:
**
**      char *zText = "It's a happy day!";
**
** We can use this text in an SQL statement as follows:
**
**      sqlite3_exec_printf(db, "INSERT INTO table VALUES('%q')",
**          callback1, 0, 0, zText);
**
** Because the %q format string is used, the '\'' character in zText
** is escaped and the SQL generated is as follows:
**
**      INSERT INTO table1 VALUES('It''s a happy day!')
**
** This is correct.  Had we used %s instead of %q, the generated SQL
** would have looked like this:
**
**      INSERT INTO table1 VALUES('It's a happy day!');
**
** This second example is an SQL syntax error.  As a general rule you
** should always use %q instead of %s when inserting text into a string 
** literal.
*/
char *sqlite3_mprintf(const char*,...);
char *sqlite3_vmprintf(const char*, va_list);
void sqlite3_free(char *z);
char *sqlite3_snprintf(int,char*,const char*, ...);

#ifndef SQLITE_OMIT_AUTHORIZATION
/*
** This routine registers a callback with the SQLite library.  The
** callback is invoked (at compile-time, not at run-time) for each
** attempt to access a column of a table in the database.  The callback
** returns SQLITE_OK if access is allowed, SQLITE_DENY if the entire
** SQL statement should be aborted with an error and SQLITE_IGNORE
** if the column should be treated as a NULL value.
*/
int sqlite3_set_authorizer(
  sqlite3*,
  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
  void *pUserData
);
#endif

/*
** The second parameter to the access authorization function above will
** be one of the values below.  These values signify what kind of operation
** is to be authorized.  The 3rd and 4th parameters to the authorization
** function will be parameters or NULL depending on which of the following
** codes is used as the second parameter.  The 5th parameter is the name
** of the database ("main", "temp", etc.) if applicable.  The 6th parameter
** is the name of the inner-most trigger or view that is responsible for
** the access attempt or NULL if this access attempt is directly from 
** input SQL code.
**
**                                          Arg-3           Arg-4
*/
#define SQLITE_COPY                  0   /* Table Name      File Name       */
#define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
#define SQLITE_CREATE_TABLE          2   /* Table Name      NULL            */
#define SQLITE_CREATE_TEMP_INDEX     3   /* Index Name      Table Name      */
#define SQLITE_CREATE_TEMP_TABLE     4   /* Table Name      NULL            */
#define SQLITE_CREATE_TEMP_TRIGGER   5   /* Trigger Name    Table Name      */
#define SQLITE_CREATE_TEMP_VIEW      6   /* View Name       NULL            */
#define SQLITE_CREATE_TRIGGER        7   /* Trigger Name    Table Name      */
#define SQLITE_CREATE_VIEW           8   /* View Name       NULL            */
#define SQLITE_DELETE                9   /* Table Name      NULL            */
#define SQLITE_DROP_INDEX           10   /* Index Name      Table Name      */
#define SQLITE_DROP_TABLE           11   /* Table Name      NULL            */
#define SQLITE_DROP_TEMP_INDEX      12   /* Index Name      Table Name      */
#define SQLITE_DROP_TEMP_TABLE      13   /* Table Name      NULL            */
#define SQLITE_DROP_TEMP_TRIGGER    14   /* Trigger Name    Table Name      */
#define SQLITE_DROP_TEMP_VIEW       15   /* View Name       NULL            */
#define SQLITE_DROP_TRIGGER         16   /* Trigger Name    Table Name      */
#define SQLITE_DROP_VIEW            17   /* View Name       NULL            */
#define SQLITE_INSERT               18   /* Table Name      NULL            */
#define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
#define SQLITE_READ                 20   /* Table Name      Column Name     */
#define SQLITE_SELECT               21   /* NULL            NULL            */
#define SQLITE_TRANSACTION          22   /* NULL            NULL            */
#define SQLITE_UPDATE               23   /* Table Name      Column Name     */
#define SQLITE_ATTACH               24   /* Filename        NULL            */
#define SQLITE_DETACH               25   /* Database Name   NULL            */
#define SQLITE_ALTER_TABLE          26   /* Database Name   Table Name      */
#define SQLITE_REINDEX              27   /* Index Name      NULL            */


/*
** The return value of the authorization function should be one of the
** following constants:
*/
/* #define SQLITE_OK  0   // Allow access (This is actually defined above) */
#define SQLITE_DENY   1   /* Abort the SQL statement with an error */
#define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */

/*
** Register a function that is called at every invocation of sqlite3_exec()
** or sqlite3_prepare().  This function can be used (for example) to generate
** a log file of all SQL executed against a database.
*/
void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);

/*
** This routine configures a callback function - the progress callback - that
** is invoked periodically during long running calls to sqlite3_exec(),
** sqlite3_step() and sqlite3_get_table(). An example use for this API is to 
** keep a GUI updated during a large query.
**
** The progress callback is invoked once for every N virtual machine opcodes,
** where N is the second argument to this function. The progress callback
** itself is identified by the third argument to this function. The fourth
** argument to this function is a void pointer passed to the progress callback
** function each time it is invoked.
**
** If a call to sqlite3_exec(), sqlite3_step() or sqlite3_get_table() results 
** in less than N opcodes being executed, then the progress callback is not
** invoked.
** 
** To remove the progress callback altogether, pass NULL as the third
** argument to this function.
**
** If the progress callback returns a result other than 0, then the current 
** query is immediately terminated and any database changes rolled back. If the
** query was part of a larger transaction, then the transaction is not rolled
** back and remains active. The sqlite3_exec() call returns SQLITE_ABORT. 
**
******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ******
*/
void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);

/*
** Register a callback function to be invoked whenever a new transaction
** is committed.  The pArg argument is passed through to the callback.
** callback.  If the callback function returns non-zero, then the commit
** is converted into a rollback.
**
** If another function was previously registered, its pArg value is returned.
** Otherwise NULL is returned.
**
** Registering a NULL function disables the callback.
**
******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ******
*/
void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);

/*
** Open the sqlite database file "filename".  The "filename" is UTF-8
** encoded for sqlite3_open() and UTF-16 encoded in the native byte order
** for sqlite3_open16().  An sqlite3* handle is returned in *ppDb, even
** if an error occurs. If the database is opened (or created) successfully,
** then SQLITE_OK is returned. Otherwise an error code is returned. The
** sqlite3_errmsg() or sqlite3_errmsg16()  routines can be used to obtain
** an English language description of the error.
**
** If the database file does not exist, then a new database is created.
** The encoding for the database is UTF-8 if sqlite3_open() is called and
** UTF-16 if sqlite3_open16 is used.
**
** Whether or not an error occurs when it is opened, resources associated
** with the sqlite3* handle should be released by passing it to
** sqlite3_close() when it is no longer required.
*/
int sqlite3_open(
  const char *filename,   /* Database filename (UTF-8) */
  sqlite3 **ppDb          /* OUT: SQLite db handle */
);
int sqlite3_open16(
  const void *filename,   /* Database filename (UTF-16) */
  sqlite3 **ppDb          /* OUT: SQLite db handle */
);

/*
** Return the error code for the most recent sqlite3_* API call associated
** with sqlite3 handle 'db'. SQLITE_OK is returned if the most recent 
** API call was successful.
**
** Calls to many sqlite3_* functions set the error code and string returned
** by sqlite3_errcode(), sqlite3_errmsg() and sqlite3_errmsg16()
** (overwriting the previous values). Note that calls to sqlite3_errcode(),
** sqlite3_errmsg() and sqlite3_errmsg16() themselves do not affect the
** results of future invocations.
**
** Assuming no other intervening sqlite3_* API calls are made, the error
** code returned by this function is associated with the same error as
** the strings  returned by sqlite3_errmsg() and sqlite3_errmsg16().
*/
int sqlite3_errcode(sqlite3 *db);

/*
** Return a pointer to a UTF-8 encoded string describing in english the
** error condition for the most recent sqlite3_* API call. The returned
** string is always terminated by an 0x00 byte.
**
** The string "not an error" is returned when the most recent API call was
** successful.
*/
const char *sqlite3_errmsg(sqlite3*);

/*
** Return a pointer to a UTF-16 native byte order encoded string describing
** in english the error condition for the most recent sqlite3_* API call.
** The returned string is always terminated by a pair of 0x00 bytes.
**
** The string "not an error" is returned when the most recent API call was
** successful.
*/
const void *sqlite3_errmsg16(sqlite3*);

/*
** An instance of the following opaque structure is used to represent
** a compiled SQL statment.
*/
typedef struct sqlite3_stmt sqlite3_stmt;

/*
** To execute an SQL query, it must first be compiled into a byte-code
** program using one of the following routines. The only difference between
** them is that the second argument, specifying the SQL statement to
** compile, is assumed to be encoded in UTF-8 for the sqlite3_prepare()
** function and UTF-16 for sqlite3_prepare16().
**
** The first parameter "db" is an SQLite database handle. The second
** parameter "zSql" is the statement to be compiled, encoded as either
** UTF-8 or UTF-16 (see above). If the next parameter, "nBytes", is less
** than zero, then zSql is read up to the first nul terminator.  If
** "nBytes" is not less than zero, then it is the length of the string zSql
** in bytes (not characters).
**
** *pzTail is made to point to the first byte past the end of the first
** SQL statement in zSql.  This routine only compiles the first statement
** in zSql, so *pzTail is left pointing to what remains uncompiled.
**
** *ppStmt is left pointing to a compiled SQL statement that can be
** executed using sqlite3_step().  Or if there is an error, *ppStmt may be
** set to NULL.  If the input text contained no SQL (if the input is and
** empty string or a comment) then *ppStmt is set to NULL.
**
** On success, SQLITE_OK is returned.  Otherwise an error code is returned.
*/
int sqlite3_prepare(
  sqlite3 *db,            /* Database handle */
  const char *zSql,       /* SQL statement, UTF-8 encoded */
  int nBytes,             /* Length of zSql in bytes. */
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
);
int sqlite3_prepare16(
  sqlite3 *db,            /* Database handle */
  const void *zSql,       /* SQL statement, UTF-16 encoded */
  int nBytes,             /* Length of zSql in bytes. */
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
);

/*
** Pointers to the following two opaque structures are used to communicate
** with the implementations of user-defined functions.
*/
typedef struct sqlite3_context sqlite3_context;
typedef struct Mem sqlite3_value;

/*
** In the SQL strings input to sqlite3_prepare() and sqlite3_prepare16(),
** one or more literals can be replace by parameters "?" or ":AAA" or
** "$VVV" where AAA is an identifer and VVV is a variable name according