Re: BUG #17633: Define rule on views which do insert to another relation trigger cache lookup failed error.

On Tue, 11 Oct 2022 at 20:09, Richard Guo <guofenglinux@gmail.com> wrote:
>
> I think the problem exists for auto-updatable view, as we leave the
> DEFAULT items untouched because we expect to apply the underlying base
> rel's default.
>
> In this case there is a rewrite rule on the view.  Applying the rule
> we'd get a product query whose target entries referring to the VALUES
> RTE have attribute 3 and 4 while the relation has only two attributes.
> Then we proceed to replacing the remaining DEFAULT items with NULLs.
> And when we try to access the relation's 3rd and 4th attributes, we are
> accessing illegal memory areas.
>

Yeah, I also notice this, attch a patch to fix it.

-- 
Regrads,
Japin Li.
ChengDu WenWu Information Technology Co.,Ltd.

diff --git a/src/backend/rewrite/rewriteHandler.c b/src/backend/rewrite/rewriteHandler.c
index d02fd83c0a..2f77ff87dc 100644
--- a/src/backend/rewrite/rewriteHandler.c
+++ b/src/backend/rewrite/rewriteHandler.c
@@ -3857,13 +3857,20 @@ RewriteQuery(Query *parsetree, List *rewrite_events)
             foreach(n, product_queries)
             {
                 Query       *pt = (Query *) lfirst(n);
+                Relation    target_relation;
+                RangeTblEntry *target_entry;
                 RangeTblEntry *values_rte = rt_fetch(values_rte_index,
                                                      pt->rtable);
 
+                target_entry = rt_fetch(pt->resultRelation, pt->rtable);
+                target_relation = table_open(target_entry->relid, NoLock);
+
                 rewriteValuesRTE(pt, values_rte, values_rte_index,
-                                 rt_entry_relation,
+                                 target_relation,
                                  true,    /* Force remaining defaults to NULL */
                                  NULL);
+
+                table_close(target_relation, NoLock);
             }
         }