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-rw-r--r--src/wherecode.c158
1 files changed, 0 insertions, 158 deletions
diff --git a/src/wherecode.c b/src/wherecode.c
index c2e7278d1..a1ecf93b8 100644
--- a/src/wherecode.c
+++ b/src/wherecode.c
@@ -1217,143 +1217,6 @@ static void codeExprOrVector(Parse *pParse, Expr *p, int iReg, int nReg){
}
}
-/* An instance of the IdxExprTrans object carries information about a
-** mapping from an expression on table columns into a column in an index
-** down through the Walker.
-*/
-typedef struct IdxExprTrans {
- Expr *pIdxExpr; /* The index expression */
- int iTabCur; /* The cursor of the corresponding table */
- int iIdxCur; /* The cursor for the index */
- int iIdxCol; /* The column for the index */
- int iTabCol; /* The column for the table */
- WhereInfo *pWInfo; /* Complete WHERE clause information */
- sqlite3 *db; /* Database connection (for malloc()) */
-} IdxExprTrans;
-
-/*
-** Preserve pExpr on the WhereETrans list of the WhereInfo.
-*/
-static void preserveExpr(IdxExprTrans *pTrans, Expr *pExpr){
- WhereExprMod *pNew;
- pNew = sqlite3DbMallocRaw(pTrans->db, sizeof(*pNew));
- if( pNew==0 ) return;
- pNew->pNext = pTrans->pWInfo->pExprMods;
- pTrans->pWInfo->pExprMods = pNew;
- pNew->pExpr = pExpr;
- memcpy(&pNew->orig, pExpr, sizeof(*pExpr));
-}
-
-/* The walker node callback used to transform matching expressions into
-** a reference to an index column for an index on an expression.
-**
-** If pExpr matches, then transform it into a reference to the index column
-** that contains the value of pExpr.
-*/
-static int whereIndexExprTransNode(Walker *p, Expr *pExpr){
- IdxExprTrans *pX = p->u.pIdxTrans;
- if( sqlite3ExprCompare(0, pExpr, pX->pIdxExpr, pX->iTabCur)==0 ){
- pExpr = sqlite3ExprSkipCollate(pExpr);
- preserveExpr(pX, pExpr);
- pExpr->affExpr = sqlite3ExprAffinity(pExpr);
- pExpr->op = TK_COLUMN;
- pExpr->iTable = pX->iIdxCur;
- pExpr->iColumn = pX->iIdxCol;
- testcase( ExprHasProperty(pExpr, EP_Unlikely) );
- ExprClearProperty(pExpr, EP_Skip|EP_Unlikely|EP_WinFunc|EP_Subrtn);
- pExpr->y.pTab = 0;
- return WRC_Prune;
- }else{
- return WRC_Continue;
- }
-}
-
-#ifndef SQLITE_OMIT_GENERATED_COLUMNS
-/* A walker node callback that translates a column reference to a table
-** into a corresponding column reference of an index.
-*/
-static int whereIndexExprTransColumn(Walker *p, Expr *pExpr){
- if( pExpr->op==TK_COLUMN ){
- IdxExprTrans *pX = p->u.pIdxTrans;
- if( pExpr->iTable==pX->iTabCur && pExpr->iColumn==pX->iTabCol ){
- assert( ExprUseYTab(pExpr) && pExpr->y.pTab!=0 );
- preserveExpr(pX, pExpr);
- pExpr->affExpr = sqlite3TableColumnAffinity(pExpr->y.pTab,pExpr->iColumn);
- pExpr->iTable = pX->iIdxCur;
- pExpr->iColumn = pX->iIdxCol;
- pExpr->y.pTab = 0;
- }
- }
- return WRC_Continue;
-}
-#endif /* SQLITE_OMIT_GENERATED_COLUMNS */
-
-/*
-** For an indexes on expression X, locate every instance of expression X
-** in pExpr and change that subexpression into a reference to the appropriate
-** column of the index.
-**
-** 2019-10-24: Updated to also translate references to a VIRTUAL column in
-** the table into references to the corresponding (stored) column of the
-** index.
-*/
-static void whereIndexExprTrans(
- Index *pIdx, /* The Index */
- int iTabCur, /* Cursor of the table that is being indexed */
- int iIdxCur, /* Cursor of the index itself */
- WhereInfo *pWInfo /* Transform expressions in this WHERE clause */
-){
- int iIdxCol; /* Column number of the index */
- ExprList *aColExpr; /* Expressions that are indexed */
- Table *pTab;
- Walker w;
- IdxExprTrans x;
- aColExpr = pIdx->aColExpr;
- if( aColExpr==0 && !pIdx->bHasVCol ){
- /* The index does not reference any expressions or virtual columns
- ** so no translations are needed. */
- return;
- }
- pTab = pIdx->pTable;
- memset(&w, 0, sizeof(w));
- w.u.pIdxTrans = &x;
- x.iTabCur = iTabCur;
- x.iIdxCur = iIdxCur;
- x.pWInfo = pWInfo;
- x.db = pWInfo->pParse->db;
- for(iIdxCol=0; iIdxCol<pIdx->nColumn; iIdxCol++){
- i16 iRef = pIdx->aiColumn[iIdxCol];
- if( iRef==XN_EXPR ){
- assert( aColExpr!=0 && aColExpr->a[iIdxCol].pExpr!=0 );
- x.pIdxExpr = aColExpr->a[iIdxCol].pExpr;
- if( sqlite3ExprIsConstant(x.pIdxExpr) ) continue;
- w.xExprCallback = whereIndexExprTransNode;
-#ifndef SQLITE_OMIT_GENERATED_COLUMNS
- }else if( iRef>=0
- && (pTab->aCol[iRef].colFlags & COLFLAG_VIRTUAL)!=0
- && ((pTab->aCol[iRef].colFlags & COLFLAG_HASCOLL)==0
- || sqlite3StrICmp(sqlite3ColumnColl(&pTab->aCol[iRef]),
- sqlite3StrBINARY)==0)
- ){
- /* Check to see if there are direct references to generated columns
- ** that are contained in the index. Pulling the generated column
- ** out of the index is an optimization only - the main table is always
- ** available if the index cannot be used. To avoid unnecessary
- ** complication, omit this optimization if the collating sequence for
- ** the column is non-standard */
- x.iTabCol = iRef;
- w.xExprCallback = whereIndexExprTransColumn;
-#endif /* SQLITE_OMIT_GENERATED_COLUMNS */
- }else{
- continue;
- }
- x.iIdxCol = iIdxCol;
- sqlite3WalkExpr(&w, pWInfo->pWhere);
- sqlite3WalkExprList(&w, pWInfo->pOrderBy);
- sqlite3WalkExprList(&w, pWInfo->pResultSet);
- }
-}
-
/*
** The pTruth expression is always true because it is the WHERE clause
** a partial index that is driving a query loop. Look through all of the
@@ -2181,27 +2044,6 @@ Bitmask sqlite3WhereCodeOneLoopStart(
}
if( pLevel->iLeftJoin==0 ){
- /* If pIdx is an index on one or more expressions, then look through
- ** all the expressions in pWInfo and try to transform matching expressions
- ** into reference to index columns. Also attempt to translate references
- ** to virtual columns in the table into references to (stored) columns
- ** of the index.
- **
- ** Do not do this for the RHS of a LEFT JOIN. This is because the
- ** expression may be evaluated after OP_NullRow has been executed on
- ** the cursor. In this case it is important to do the full evaluation,
- ** as the result of the expression may not be NULL, even if all table
- ** column values are. https://www.sqlite.org/src/info/7fa8049685b50b5a
- **
- ** Also, do not do this when processing one index an a multi-index
- ** OR clause, since the transformation will become invalid once we
- ** move forward to the next index.
- ** https://sqlite.org/src/info/4e8e4857d32d401f
- */
- if( (pWInfo->wctrlFlags & (WHERE_OR_SUBCLAUSE|WHERE_RIGHT_JOIN))==0 ){
- whereIndexExprTrans(pIdx, iCur, iIdxCur, pWInfo);
- }
-
/* If a partial index is driving the loop, try to eliminate WHERE clause
** terms from the query that must be true due to the WHERE clause of
** the partial index.
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-17 15:11:41 +0000