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-rw-r--r--src/wherecode.c52
1 files changed, 45 insertions, 7 deletions
diff --git a/src/wherecode.c b/src/wherecode.c
index 686a8d6f9..0438cca54 100644
--- a/src/wherecode.c
+++ b/src/wherecode.c
@@ -1106,6 +1106,7 @@ typedef struct IdxExprTrans {
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 */
} IdxExprTrans;
/* The walker node callback used to transform matching expressions into
@@ -1128,10 +1129,30 @@ static int whereIndexExprTransNode(Walker *p, Expr *pExpr){
}
}
+#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 ){
+ pExpr->iTable = pX->iIdxCur;
+ pExpr->iColumn = pX->iIdxCol;
+ }
+ }
+ 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 */
@@ -1141,20 +1162,35 @@ static void whereIndexExprTrans(
){
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 ) return; /* Not an index on expressions */
+ 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.xExprCallback = whereIndexExprTransNode;
w.u.pIdxTrans = &x;
x.iTabCur = iTabCur;
x.iIdxCur = iIdxCur;
- for(iIdxCol=0; iIdxCol<aColExpr->nExpr; iIdxCol++){
- if( pIdx->aiColumn[iIdxCol]!=XN_EXPR ) continue;
- assert( aColExpr->a[iIdxCol].pExpr!=0 );
+ for(iIdxCol=0; iIdxCol<pIdx->nColumn; iIdxCol++){
+ i16 iRef = pIdx->aiColumn[iIdxCol];
+ if( iRef==XN_EXPR ){
+ assert( aColExpr->a[iIdxCol].pExpr!=0 );
+ x.pIdxExpr = aColExpr->a[iIdxCol].pExpr;
+ w.xExprCallback = whereIndexExprTransNode;
+#ifndef SQLITE_OMIT_GENERATED_COLUMNS
+ }else if( iRef>=0 && (pTab->aCol[iRef].colFlags & COLFLAG_VIRTUAL)!=0 ){
+ x.iTabCol = iRef;
+ w.xExprCallback = whereIndexExprTransColumn;
+#endif /* SQLITE_OMIT_GENERATED_COLUMNS */
+ }else{
+ continue;
+ }
x.iIdxCol = iIdxCol;
- x.pIdxExpr = aColExpr->a[iIdxCol].pExpr;
sqlite3WalkExpr(&w, pWInfo->pWhere);
sqlite3WalkExprList(&w, pWInfo->pOrderBy);
sqlite3WalkExprList(&w, pWInfo->pResultSet);
@@ -1835,7 +1871,9 @@ Bitmask sqlite3WhereCodeOneLoopStart(
/* 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.
+ ** 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