When the left table of a RIGHT JOIN is used inside an aggregate function and the left table employs an index on expressions, then make sure the expressions evaluate to NULL for the cases where the left table should be NULL. Fix for

[forum:/forumpost/9b491e1deb|forum post 9b491e1deb].

FossilOrigin-Name: ffe23af73fcb324df988a00be343654ce7078b7208647c4eb779d666b8297e7c

1 files changed, 13 insertions, 1 deletions

diff --git a/src/expr.c b/src/expr.c
index 9e2ae0ebd..cd09c0d71 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -4222,7 +4222,19 @@ expr_code_doover:
       AggInfo *pAggInfo = pExpr->pAggInfo;
       struct AggInfo_col *pCol;
       assert( pAggInfo!=0 );
-      assert( pExpr->iAgg>=0 && pExpr->iAgg<pAggInfo->nColumn );
+      assert( pExpr->iAgg>=0 );
+      if( pExpr->iAgg>=pAggInfo->nColumn ){
+        /* Happens when the left table of a RIGHT JOIN is null and
+        ** is using an expression index */
+        sqlite3VdbeAddOp2(v, OP_Null, 0, target);
+#ifdef SQLITE_VDBE_COVERAGE
+        /* Verify that the OP_Null above is exercised by tests
+        ** tag-20230325-2 */
+        sqlite3VdbeAddOp2(v, OP_NotNull, target, 1);
+        VdbeCoverageNeverTaken(v);
+#endif
+        break;
+      }
       pCol = &pAggInfo->aCol[pExpr->iAgg];
       if( !pAggInfo->directMode ){
         return AggInfoColumnReg(pAggInfo, pExpr->iAgg);