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-rw-r--r--src/expr.c93
-rw-r--r--src/where.c1
2 files changed, 74 insertions, 20 deletions
diff --git a/src/expr.c b/src/expr.c
index cc915987d..d0282f714 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -6180,16 +6180,23 @@ void sqlite3ExprIfFalseDup(Parse *pParse, Expr *pExpr, int dest,int jumpIfNull){
** same as that currently bound to variable pVar, non-zero is returned.
** Otherwise, if the values are not the same or if pExpr is not a simple
** SQL value, zero is returned.
+**
+** If the SQLITE_EnableQPSG flag is set on the database connection, then
+** this routine always returns false.
*/
-static int exprCompareVariable(
+static SQLITE_NOINLINE int exprCompareVariable(
const Parse *pParse,
const Expr *pVar,
const Expr *pExpr
){
- int res = 0;
+ int res = 2;
int iVar;
sqlite3_value *pL, *pR = 0;
+ if( pExpr->op==TK_VARIABLE && pVar->iColumn==pExpr->iColumn ){
+ return 0;
+ }
+ if( (pParse->db->flags & SQLITE_EnableQPSG)!=0 ) return 2;
sqlite3ValueFromExpr(pParse->db, pExpr, SQLITE_UTF8, SQLITE_AFF_BLOB, &pR);
if( pR ){
iVar = pVar->iColumn;
@@ -6199,12 +6206,11 @@ static int exprCompareVariable(
if( sqlite3_value_type(pL)==SQLITE_TEXT ){
sqlite3_value_text(pL); /* Make sure the encoding is UTF-8 */
}
- res = 0==sqlite3MemCompare(pL, pR, 0);
+ res = sqlite3MemCompare(pL, pR, 0) ? 2 : 0;
}
sqlite3ValueFree(pR);
sqlite3ValueFree(pL);
}
-
return res;
}
@@ -6230,12 +6236,10 @@ static int exprCompareVariable(
** just might result in some slightly slower code. But returning
** an incorrect 0 or 1 could lead to a malfunction.
**
-** If pParse is not NULL then TK_VARIABLE terms in pA with bindings in
-** pParse->pReprepare can be matched against literals in pB. The
-** pParse->pVdbe->expmask bitmask is updated for each variable referenced.
-** If pParse is NULL (the normal case) then any TK_VARIABLE term in
-** Argument pParse should normally be NULL. If it is not NULL and pA or
-** pB causes a return value of 2.
+** If pParse is not NULL and SQLITE_EnableQPSG is off then TK_VARIABLE
+** terms in pA with bindings in pParse->pReprepare can be matched against
+** literals in pB. The pParse->pVdbe->expmask bitmask is updated for
+** each variable referenced.
*/
int sqlite3ExprCompare(
const Parse *pParse,
@@ -6247,8 +6251,8 @@ int sqlite3ExprCompare(
if( pA==0 || pB==0 ){
return pB==pA ? 0 : 2;
}
- if( pParse && pA->op==TK_VARIABLE && exprCompareVariable(pParse, pA, pB) ){
- return 0;
+ if( pParse && pA->op==TK_VARIABLE ){
+ return exprCompareVariable(pParse, pA, pB);
}
combinedFlags = pA->flags | pB->flags;
if( combinedFlags & EP_IntValue ){
@@ -6444,17 +6448,65 @@ static int exprImpliesNotNull(
}
/*
+** Return true if the boolean value of the expression is always either
+** FALSE or NULL.
+*/
+static int sqlite3ExprIsNotTrue(Expr *pExpr){
+ int v;
+ if( pExpr->op==TK_NULL ) return 1;
+ if( pExpr->op==TK_TRUEFALSE && sqlite3ExprTruthValue(pExpr)==0 ) return 1;
+ v = 1;
+ if( sqlite3ExprIsInteger(pExpr, &v, 0) && v==0 ) return 1;
+ return 0;
+}
+
+/*
+** Return true if the expression is one of the following:
+**
+** CASE WHEN x THEN y END
+** CASE WHEN x THEN y ELSE NULL END
+** CASE WHEN x THEN y ELSE false END
+** iif(x,y)
+** iif(x,y,NULL)
+** iif(x,y,false)
+*/
+static int sqlite3ExprIsIIF(sqlite3 *db, const Expr *pExpr){
+ ExprList *pList;
+ if( pExpr->op==TK_FUNCTION ){
+ const char *z = pExpr->u.zToken;
+ FuncDef *pDef;
+ if( (z[0]!='i' && z[0]!='I') ) return 0;
+ if( pExpr->x.pList==0 ) return 0;
+ pDef = sqlite3FindFunction(db, z, pExpr->x.pList->nExpr, ENC(db), 0);
+ if( NEVER(pDef==0) ) return 0;
+ if( (pDef->funcFlags & SQLITE_FUNC_INLINE)==0 ) return 0;
+ if( NEVER(SQLITE_PTR_TO_INT(pDef->pUserData)!=INLINEFUNC_iif) ) return 0;
+ }else if( pExpr->op==TK_CASE ){
+ if( pExpr->pLeft!=0 ) return 0;
+ }else{
+ return 0;
+ }
+ pList = pExpr->x.pList;
+ assert( pList!=0 );
+ if( pList->nExpr==2 ) return 1;
+ if( pList->nExpr==3 && sqlite3ExprIsNotTrue(pList->a[2].pExpr) ) return 1;
+ return 0;
+}
+
+/*
** Return true if we can prove the pE2 will always be true if pE1 is
** true. Return false if we cannot complete the proof or if pE2 might
** be false. Examples:
**
-** pE1: x==5 pE2: x==5 Result: true
-** pE1: x>0 pE2: x==5 Result: false
-** pE1: x=21 pE2: x=21 OR y=43 Result: true
-** pE1: x!=123 pE2: x IS NOT NULL Result: true
-** pE1: x!=?1 pE2: x IS NOT NULL Result: true
-** pE1: x IS NULL pE2: x IS NOT NULL Result: false
-** pE1: x IS ?2 pE2: x IS NOT NULL Result: false
+** pE1: x==5 pE2: x==5 Result: true
+** pE1: x>0 pE2: x==5 Result: false
+** pE1: x=21 pE2: x=21 OR y=43 Result: true
+** pE1: x!=123 pE2: x IS NOT NULL Result: true
+** pE1: x!=?1 pE2: x IS NOT NULL Result: true
+** pE1: x IS NULL pE2: x IS NOT NULL Result: false
+** pE1: x IS ?2 pE2: x IS NOT NULL Result: false
+** pE1: iif(x,y) pE2: x Result: true
+** PE1: iif(x,y,0) pE2: x Result: true
**
** When comparing TK_COLUMN nodes between pE1 and pE2, if pE2 has
** Expr.iTable<0 then assume a table number given by iTab.
@@ -6488,6 +6540,9 @@ int sqlite3ExprImpliesExpr(
){
return 1;
}
+ if( sqlite3ExprIsIIF(pParse->db, pE1) ){
+ return sqlite3ExprImpliesExpr(pParse,pE1->x.pList->a[0].pExpr,pE2,iTab);
+ }
return 0;
}
diff --git a/src/where.c b/src/where.c
index 1315a8cc3..5abb40ece 100644
--- a/src/where.c
+++ b/src/where.c
@@ -3564,7 +3564,6 @@ static int whereUsablePartialIndex(
if( !whereUsablePartialIndex(iTab,jointype,pWC,pWhere->pLeft) ) return 0;
pWhere = pWhere->pRight;
}
- if( pParse->db->flags & SQLITE_EnableQPSG ) pParse = 0;
for(i=0, pTerm=pWC->a; i<pWC->nTerm; i++, pTerm++){
Expr *pExpr;
pExpr = pTerm->pExpr;
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-19 12:56:23 +0000