SQLite

    }
  }
  sqlite3ReleaseTempReg(pParse, regFree1);
  sqlite3ReleaseTempReg(pParse, regFree2);
}

/*
** Do a deep comparison of two expression trees.  Return 0 if the two
** expressions are completely identical.  Return 1 if they differ only
** by a COLLATE operator at the top level.  Return 2 if there are differences
** other than the top-level COLLATE operator.
**
** Sometimes this routine will return 2 even if the two expressions
** really are equivalent.  If we cannot prove that the expressions are
** identical, we return 2 just to be safe.  So if this routine
** returns 2, then you do not really know for certain if the two
** expressions are the same.  But if you get a 0 or 1 return, then you
** can be sure the expressions are the same.  In the places where
** this routine is used, it does not hurt to get an extra 2 - that
** just might result in some slightly slower code.  But returning
** an incorrect 0 or 1 could lead to a malfunction.
*/
int sqlite3ExprCompare(Expr *pA, Expr *pB){
  int i;
  if( pA==0||pB==0 ){
    return pB==pA ? 0 : 2;
  }
  assert( !ExprHasAnyProperty(pA, EP_TokenOnly|EP_Reduced) );
  assert( !ExprHasAnyProperty(pB, EP_TokenOnly|EP_Reduced) );
  if( ExprHasProperty(pA, EP_xIsSelect) || ExprHasProperty(pB, EP_xIsSelect) ){
    return 2;
  }
  if( (pA->flags & EP_Distinct)!=(pB->flags & EP_Distinct) ) return 2;
  if( pA->op!=pB->op ) return 2;
  if( sqlite3ExprCompare(pA->pLeft, pB->pLeft) ) return 2;
  if( sqlite3ExprCompare(pA->pRight, pB->pRight) ) return 2;

  if( pA->x.pList && pB->x.pList ){
    if( pA->x.pList->nExpr!=pB->x.pList->nExpr ) return 2;
    for(i=0; i<pA->x.pList->nExpr; i++){
      Expr *pExprA = pA->x.pList->a[i].pExpr;
      Expr *pExprB = pB->x.pList->a[i].pExpr;
      if( sqlite3ExprCompare(pExprA, pExprB) ) return 2;
    }
  }else if( pA->x.pList || pB->x.pList ){
    return 2;
  }

  if( pA->iTable!=pB->iTable || pA->iColumn!=pB->iColumn ) return 2;
  if( ExprHasProperty(pA, EP_IntValue) ){
    if( !ExprHasProperty(pB, EP_IntValue) || pA->u.iValue!=pB->u.iValue ){
      return 2;
    }
  }else if( pA->op!=TK_COLUMN && pA->u.zToken ){
    if( ExprHasProperty(pB, EP_IntValue) || NEVER(pB->u.zToken==0) ) return 2;
    if( sqlite3StrICmp(pA->u.zToken,pB->u.zToken)!=0 ){
      return 2;
    }
  }
  if( (pA->flags & EP_ExpCollate)!=(pB->flags & EP_ExpCollate) ) return 1;
  if( (pA->flags & EP_ExpCollate)!=0 && pA->pColl!=pB->pColl ) return 2;
  return 0;
}


/*
** Add a new element to the pAggInfo->aCol[] array.  Return the index of
** the new element.  Return a negative number if malloc fails.
*/

      ** to be ignored */
      if( pNC->nDepth==0 ){
        /* Check to see if pExpr is a duplicate of another aggregate 
        ** function that is already in the pAggInfo structure
        */
        struct AggInfo_func *pItem = pAggInfo->aFunc;
        for(i=0; i<pAggInfo->nFunc; i++, pItem++){
          if( sqlite3ExprCompare(pItem->pExpr, pExpr)==0 ){
            break;
          }
        }
        if( i>=pAggInfo->nFunc ){
          /* pExpr is original.  Make a new entry in pAggInfo->aFunc[]
          */
          u8 enc = ENC(pParse->db);

      if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break;
    }
    if( pSrcIdx==0 ){
      return 0;    /* pDestIdx has no corresponding index in pSrc */
    }
  }
#ifndef SQLITE_OMIT_CHECK
  if( pDest->pCheck && sqlite3ExprCompare(pSrc->pCheck, pDest->pCheck) ){
    return 0;   /* Tables have different CHECK constraints.  Ticket #2252 */
  }
#endif

  /* If we get this far, it means either:
  **
  **    *   We can always do the transfer if the table contains an

  }

  /* Try to match the ORDER BY expression against an expression
  ** in the result set.  Return an 1-based index of the matching
  ** result-set entry.
  */
  for(i=0; i<pEList->nExpr; i++){
    if( sqlite3ExprCompare(pEList->a[i].pExpr, pE)<2 ){
      return i+1;
    }
  }

  /* If no match, return 0. */
  return 0;
}

    CREATE INDEX t2_i1 ON t2(x ASC, y COLLATE RTRIM);
    INSERT INTO t2 SELECT * FROM t3;
  }
  set ::sqlite3_xferopt_count
} {0}


do_test insert4-6.5 {
  execsql {
    CREATE TABLE t6a(x CHECK( x<>'abc' ));
    INSERT INTO t6a VALUES('ABC');
    SELECT * FROM t6a;
  }
} {ABC}
do_test insert4-6.6 {
  execsql {
    CREATE TABLE t6b(x CHECK( x<>'abc' COLLATE nocase ));
  }
  catchsql {
    INSERT INTO t6b SELECT * FROM t6a;
  }
} {1 {constraint failed}}
do_test insert4-6.7 {
  execsql {
    DROP TABLE t6b;
    CREATE TABLE t6b(x CHECK( x COLLATE nocase <>'abc' ));
  }
  catchsql {
    INSERT INTO t6b SELECT * FROM t6a;
  }
} {1 {constraint failed}}

finish_test

do_test minmax3-2.7 {
  execsql { SELECT min(b) FROM t2 WHERE a = 1 AND b<1; }
} {{}}
do_test minmax3-2.8 {
  execsql { SELECT min(b) FROM t2 WHERE a = 3 AND b<1; }
} {{}}

do_test minmax3-3.1 {
  execsql {
    DROP TABLE t2;
    CREATE TABLE t2(a, b);
    CREATE INDEX i3 ON t2(a, b DESC);
    INSERT INTO t2 VALUES(1, NULL);
    INSERT INTO t2 VALUES(1, 1);
    INSERT INTO t2 VALUES(1, 2);
    INSERT INTO t2 VALUES(1, 3);
    INSERT INTO t2 VALUES(2, NULL);
    INSERT INTO t2 VALUES(2, 1);
    INSERT INTO t2 VALUES(2, 2);
    INSERT INTO t2 VALUES(2, 3);
    INSERT INTO t2 VALUES(3, 1);
    INSERT INTO t2 VALUES(3, 2);
    INSERT INTO t2 VALUES(3, 3);
  }
} {}
do_test minmax3-3.2 {
  execsql { SELECT min(b) FROM t2 WHERE a = 1; }
} {1}
do_test minmax3-3.3 {
  execsql { SELECT min(b) FROM t2 WHERE a = 1 AND b>1; }
} {2}
do_test minmax3-3.4 {
  execsql { SELECT min(b) FROM t2 WHERE a = 1 AND b>-1; }
} {1}
do_test minmax3-3.5 {
  execsql { SELECT min(b) FROM t2 WHERE a = 1; }
} {1}
do_test minmax3-3.6 {
  execsql { SELECT min(b) FROM t2 WHERE a = 1 AND b<2; }
} {1}
do_test minmax3-3.7 {
  execsql { SELECT min(b) FROM t2 WHERE a = 1 AND b<1; }
} {{}}
do_test minmax3-3.8 {
  execsql { SELECT min(b) FROM t2 WHERE a = 3 AND b<1; }
} {{}}

do_test minmax3-4.1 {
  execsql {
    CREATE TABLE t4(x);
    INSERT INTO t4 VALUES('abc');
    INSERT INTO t4 VALUES('BCD');
    SELECT max(x) FROM t4;
  }
} {abc}
do_test minmax3-4.2 {
  execsql {
    SELECT max(x COLLATE nocase) FROM t4;
  }
} {BCD}
do_test minmax3-4.3 {
  execsql {
    SELECT max(x), max(x COLLATE nocase) FROM t4;
  }
} {abc BCD}
do_test minmax3-4.4 {
  execsql {
    SELECT max(x COLLATE binary), max(x COLLATE nocase) FROM t4;
  }
} {abc BCD}
do_test minmax3-4.5 {
  execsql {
    SELECT max(x COLLATE nocase), max(x COLLATE rtrim) FROM t4;
  }
} {BCD abc}
do_test minmax3-4.6 {
  execsql {
    SELECT max(x COLLATE nocase), max(x) FROM t4;
  }
} {BCD abc}
do_test minmax3-4.10 {
  execsql {
    SELECT min(x) FROM t4;
  }
} {BCD}
do_test minmax3-4.11 {
  execsql {
    SELECT min(x COLLATE nocase) FROM t4;
  }
} {abc}
do_test minmax3-4.12 {
  execsql {
    SELECT min(x), min(x COLLATE nocase) FROM t4;
  }
} {BCD abc}
do_test minmax3-4.13 {
  execsql {
    SELECT min(x COLLATE binary), min(x COLLATE nocase) FROM t4;
  }
} {BCD abc}
do_test minmax3-4.14 {
  execsql {
    SELECT min(x COLLATE nocase), min(x COLLATE rtrim) FROM t4;
  }
} {abc BCD}
do_test minmax3-4.15 {
  execsql {
    SELECT min(x COLLATE nocase), min(x) FROM t4;
  }
} {abc BCD}


finish_test