Ensure that TK_SELECT_COLUMN Expr nodes always have their iTable field set to

to the number of columns in the vector. This is not strictly necessary. It
just simplifies the state description and make the code easier to reason about.

FossilOrigin-Name: 026f08d4cff19a95e0f38f2ef431cacd65c7c77ed92e30d7f2ded84651f47150

1 files changed, 9 insertions, 10 deletions

diff --git a/src/expr.c b/src/expr.c
index 06c3b87cd..e5f02f048 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -71,6 +71,8 @@ char sqlite3ExprAffinity(const Expr *pExpr){
 #endif
   if( op==TK_SELECT_COLUMN ){
     assert( pExpr->pLeft->flags&EP_xIsSelect );
+    assert( pExpr->iColumn < pExpr->iTable );
+    assert( pExpr->iTable==pExpr->pLeft->x.pSelect->pEList->nExpr );
     return sqlite3ExprAffinity(
         pExpr->pLeft->x.pSelect->pEList->a[pExpr->iColumn].pExpr
     );
@@ -481,7 +483,8 @@ Expr *sqlite3VectorFieldSubexpr(Expr *pVector, int i){
 Expr *sqlite3ExprForVectorField(
   Parse *pParse,       /* Parsing context */
   Expr *pVector,       /* The vector.  List of expressions or a sub-SELECT */
-  int iField           /* Which column of the vector to return */
+  int iField,          /* Which column of the vector to return */
+  int nField           /* Total number of columns in the vector */
 ){
   Expr *pRet;
   if( pVector->op==TK_SELECT ){
@@ -504,10 +507,10 @@ Expr *sqlite3ExprForVectorField(
     */
     pRet = sqlite3PExpr(pParse, TK_SELECT_COLUMN, 0, 0);
     if( pRet ){
+      pRet->iTable = nField;
       pRet->iColumn = iField;
       pRet->pLeft = pVector;
     }
-    assert( pRet==0 || pRet->iTable==0 );
   }else{
     if( pVector->op==TK_VECTOR ) pVector = pVector->x.pList->a[iField].pExpr;
     pRet = sqlite3ExprDup(pParse->db, pVector, 0);
@@ -1781,11 +1784,9 @@ ExprList *sqlite3ExprListAppendVector(
   }
 
   for(i=0; i<pColumns->nId; i++){
-    Expr *pSubExpr = sqlite3ExprForVectorField(pParse, pExpr, i);
+    Expr *pSubExpr = sqlite3ExprForVectorField(pParse, pExpr, i, pColumns->nId);
     assert( pSubExpr!=0 || db->mallocFailed );
-    assert( pSubExpr==0 || pSubExpr->iTable==0 );
     if( pSubExpr==0 ) continue;
-    pSubExpr->iTable = pColumns->nId;
     pList = sqlite3ExprListAppend(pParse, pList, pSubExpr);
     if( pList ){
       assert( pList->nExpr==iFirst+i+1 );
@@ -4375,11 +4376,9 @@ expr_code_doover:
       if( pExpr->pLeft->iTable==0 ){
         pExpr->pLeft->iTable = sqlite3CodeSubselect(pParse, pExpr->pLeft);
       }
-      assert( pExpr->iTable==0 || pExpr->pLeft->op==TK_SELECT
-               || pExpr->pLeft->op==TK_ERROR );
-      if( pExpr->iTable!=0
-       && pExpr->iTable!=(n = sqlite3ExprVectorSize(pExpr->pLeft))
-      ){
+      assert( pExpr->pLeft->op==TK_SELECT || pExpr->pLeft->op==TK_ERROR );
+      n = sqlite3ExprVectorSize(pExpr->pLeft);
+      if( pExpr->iTable!=n ){
         sqlite3ErrorMsg(pParse, "%d columns assigned %d values",
                                 pExpr->iTable, n);
       }