SQLite

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.268 2006/08/24 15:18:25 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** Return the 'affinity' of the expression pExpr if any.
**

          no_such_func = 1;
        }else{
          wrong_num_args = 1;
        }
      }else{
        is_agg = pDef->xFunc==0;
      }
#ifndef SQLITE_OMIT_AUTHORIZER
      if( pDef ){
        auth = sqlite3AuthCheck(pParse, SQLITE_FUNCTION, 0, pDef->zName, 0);
        if( auth!=SQLITE_OK ){
          if( auth==SQLITE_DENY ){
            sqlite3ErrorMsg(pParse, "not authorized to use function: %s",
                                    pDef->zName);
            pNC->nErr++;
          }
          pExpr->op = TK_NULL;
          return 1;
        }
      }
#endif
      if( is_agg && !pNC->allowAgg ){
        sqlite3ErrorMsg(pParse, "misuse of aggregate function %.*s()", nId,zId);
        pNC->nErr++;
        is_agg = 0;
      }else if( no_such_func ){
        sqlite3ErrorMsg(pParse, "no such function: %.*s", nId, zId);
        pNC->nErr++;

set rcsid {$Id: capi3ref.tcl,v 1.43 2006/08/24 15:18:25 drh Exp $}
source common.tcl
header {C/C++ Interface For SQLite Version 3}
puts {
<h2>C/C++ Interface For SQLite Version 3</h2>
}

proc api {name prototype desc {notused x}} {

#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            */
#define SQLITE_ANALYZE              28   /* Table Name      NULL            */
#define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
#define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
#define SQLITE_FUNCTION             31   /* Function Name   NULL            */

#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 */
} {
 This routine registers a callback with the SQLite library.  The
 callback is invoked by sqlite3_prepare() to authorize various
 operations against the database.  The callback should
 return SQLITE_OK if access is allowed, SQLITE_DENY if the entire
 SQL statement should be aborted with an error and SQLITE_IGNORE
 if the operation should be treated as a no-op.

 Each database connection have at most one authorizer registered
 at a time one time.  Each call
 to sqlite3_set_authorizer() overrides the previous authorizer.
 Setting the callback to NULL disables the authorizer.

 The second argument to the access authorization function will be one
 of the defined constants shown.  These values signify what kind of operation
 is to be authorized.  The 3rd and 4th arguments to the authorization
 function will be arguments or NULL depending on which of the 
 codes is used as the second argument.  For example, if the the
 2nd argument code is SQLITE_READ then the 3rd argument will be the name
 of the table that is being read from and the 4th argument will be the
 name of the column that is being read from.  Or if the 2nd argument
 is SQLITE_FUNCTION then the 3rd argument will be the name of the
 function that is being invoked and the 4th argument will be NULL.

 The 5th argument is the name
 of the database ("main", "temp", etc.) where applicable.  The 6th argument
 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.

 The return value of the authorization function should be one of the
 constants SQLITE_OK, SQLITE_DENY, or SQLITE_IGNORE.  A return of
 SQLITE_OK means that the operation is permitted and that 
 sqlite3_prepare() can proceed as normal.
 A return of SQLITE_DENY means that the sqlite3_prepare()
 should fail with an error.  A return of SQLITE_IGNORE causes the 
 sqlite3_prepare() to continue as normal but the requested 
 operation is silently converted into a no-op.  A return of SQLITE_IGNORE
 in response to an SQLITE_READ or SQLITE_FUNCTION causes the column
 being read or the function being invoked to return a NULL.

 The intent of this routine is to allow applications to safely execute
 user-entered SQL.  An appropriate callback can deny the user-entered
 SQL access certain operations (ex: anything that changes the database)
 or to deny access to certain tables or columns within the database.
}