SQLite

**
*************************************************************************
** This file contains code used to implement the sqlite3_set_authorizer()
** API.  This facility is an optional feature of the library.  Embedded
** systems that do not need this facility may omit it by recompiling
** the library with -DSQLITE_OMIT_AUTHORIZATION=1
**
** $Id: auth.c,v 1.26 2007/05/14 11:34:47 drh Exp $
*/
#include "sqliteInt.h"

/*
** All of the code in this file may be omitted by defining a single
** macro.
*/

  const char *zCol;     /* Name of the column of the table */
  int iSrc;             /* Index in pTabList->a[] of table being read */
  const char *zDBase;   /* Name of database being accessed */
  TriggerStack *pStack; /* The stack of current triggers */
  int iDb;              /* The index of the database the expression refers to */

  if( db->xAuth==0 ) return;
  if( pExpr->op!=TK_COLUMN ) return;

  iDb = sqlite3SchemaToIndex(pParse->db, pExpr->pSchema);
  if( iDb<0 ){
    /* An attempt to read a column out of a subquery or other
    ** temporary table. */
    return;
  }
  for(iSrc=0; pTabList && iSrc<pTabList->nSrc; iSrc++){

**    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 1.293 2007/05/14 11:34:47 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

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

** CREATE TABLE t1(a);
** SELECT * FROM t1 WHERE a;
** SELECT a AS b FROM t1 WHERE b;
** SELECT * FROM t1 WHERE (select a from t1);
*/
char sqlite3ExprAffinity(Expr *pExpr){
  int op = pExpr->op;



  if( op==TK_SELECT ){
    return sqlite3ExprAffinity(pExpr->pSelect->pEList->a[0].pExpr);
  }
#ifndef SQLITE_OMIT_CAST
  if( op==TK_CAST ){
    return sqlite3AffinityType(&pExpr->token);
  }

** Return the default collation sequence for the expression pExpr. If
** there is no default collation type, return 0.
*/
CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){
  CollSeq *pColl = 0;
  if( pExpr ){
    pColl = pExpr->pColl;
    if( pExpr->op==TK_CAST && !pColl ){
      return sqlite3ExprCollSeq(pParse, pExpr->pLeft);
    }
  }
  if( sqlite3CheckCollSeq(pParse, pColl) ){ 
    pColl = 0;
  }
  return pColl;

    assert( pNew->token.z==0 );
  }
  pNew->span.z = 0;
  pNew->pLeft = sqlite3ExprDup(p->pLeft);
  pNew->pRight = sqlite3ExprDup(p->pRight);
  pNew->pList = sqlite3ExprListDup(p->pList);
  pNew->pSelect = sqlite3SelectDup(p->pSelect);




  return pNew;
}
void sqlite3TokenCopy(Token *pTo, Token *pFrom){
  if( pTo->dyn ) sqliteFree((char*)pTo->z);
  if( pFrom->z ){
    pTo->n = pFrom->n;
    pTo->z = (u8*)sqliteStrNDup((char*)pFrom->z, pFrom->n);

    ** Note that the expression in the result set should have already been
    ** resolved by the time the WHERE clause is resolved.
    */
    if( cnt==0 && (pEList = pNC->pEList)!=0 && zTab==0 ){
      for(j=0; j<pEList->nExpr; j++){
        char *zAs = pEList->a[j].zName;
        if( zAs!=0 && sqlite3StrICmp(zAs, zCol)==0 ){
          Expr *pDup;
          assert( pExpr->pLeft==0 && pExpr->pRight==0 );
          assert( pExpr->pList==0 );
          assert( pExpr->pSelect==0 );
          pDup = sqlite3ExprDup(pEList->a[j].pExpr);
          if( pExpr->flags & EP_ExpCollate ){
            pDup->pColl = pExpr->pColl;
            pDup->flags |= EP_ExpCollate;
          }
          memcpy(pExpr, pDup, sizeof(*pExpr));
          sqliteFree(pDup);
          cnt = 1;
          assert( zTab==0 && zDb==0 );
          goto lookupname_end_2;
        }
      } 
    }

      pLItem++;
      pRight = pLItem->pExpr;
      sqlite3ExprCode(pParse, pRight);
      codeCompare(pParse, pLeft, pRight, OP_Le, 0, 0);
      sqlite3VdbeAddOp(v, OP_And, 0, 0);
      break;
    }
    case TK_UPLUS: {

      sqlite3ExprCode(pParse, pExpr->pLeft);
      stackChng = 0;
      break;
    }
    case TK_CASE: {
      int expr_end_label;
      int jumpInst;

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.345 2007/05/14 11:34:47 drh Exp $
*/
#include "sqliteInt.h"


/*
** Delete all the content of a Select structure but do not deallocate
** the select structure itself.

  char const *zType = 0;
  char const *zOriginDb = 0;
  char const *zOriginTab = 0;
  char const *zOriginCol = 0;
  int j;
  if( pExpr==0 || pNC->pSrcList==0 ) return 0;







  switch( pExpr->op ){
    case TK_AGG_COLUMN:
    case TK_COLUMN: {
      /* The expression is a column. Locate the table the column is being
      ** extracted from in NameContext.pSrcList. This table may be real
      ** database table or a subquery.
      */

# 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 file implements regression tests for SQLite library.  The
# focus of this file is testing the use of indices in WHERE clases.
#
# $Id: where.test,v 1.42 2007/05/14 11:34:47 drh Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Build some test data
#
do_test where-1.0 {

}

# Verify that queries use an index.  We are using the special variable
# "sqlite_search_count" which tallys the number of executions of MoveTo
# and Next operators in the VDBE.  By verifing that the search count is
# small we can be assured that indices are being used properly.
#
do_test where-1.1.1 {
  count {SELECT x, y, w FROM t1 WHERE w=10}
} {3 121 10 3}
do_test where-1.1.2 {
  set sqlite_query_plan
} {t1 i1w}
do_test where-1.1.3 {
  count {SELECT x, y, w AS abc FROM t1 WHERE abc=10}
} {3 121 10 3}
do_test where-1.1.4 {
  set sqlite_query_plan
} {t1 i1w}
do_test where-1.2.1 {
  count {SELECT x, y, w FROM t1 WHERE w=11}
} {3 144 11 3}
do_test where-1.2.2 {
  count {SELECT x, y, w AS abc FROM t1 WHERE abc=11}
} {3 144 11 3}
do_test where-1.3.1 {
  count {SELECT x, y, w AS abc FROM t1 WHERE 11=w}
} {3 144 11 3}
do_test where-1.3.2 {
  count {SELECT x, y, w AS abc FROM t1 WHERE 11=abc}
} {3 144 11 3}
do_test where-1.4.1 {
  count {SELECT w, x, y FROM t1 WHERE 11=w AND x>2}
} {11 3 144 3}
do_test where-1.4.2 {
  set sqlite_query_plan
} {t1 i1w}
do_test where-1.4.3 {
  count {SELECT w AS a, x AS b, y FROM t1 WHERE 11=a AND b>2}
} {11 3 144 3}
do_test where-1.4.4 {
  set sqlite_query_plan
} {t1 i1w}
do_test where-1.5 {
  count {SELECT x, y FROM t1 WHERE y<200 AND w=11 AND x>2}
} {3 144 3}
do_test where-1.5.2 {
  set sqlite_query_plan
} {t1 i1w}
do_test where-1.6 {