Re: Attribute of type record has wrong type error with MERGE ... WHEN NOT MATCHED BY SOURCE THEN DELETE

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Tender Wang <tndrwang@gmail.com>
Cc: Dean Rasheed <dean.a.rasheed@gmail.com>, Duncan Sands <duncan.sands@deepbluecap.com>, pgsql-bugs@lists.postgresql.org
Date: 2025-03-10T15:00:46Z
Lists: pgsql-bugs
Tender Wang <tndrwang@gmail.com> writes:
> When the query has NOT MATCHED BY SOURCE, commit d7d297f84 add "src IS NOT
> NULL" join condition.
> In this case, the src is view(e.g. subquery), so in makeWholeRowVar(), it
> will call below code:
> result = makeVar(varno,
>                       InvalidAttrNumber,
>                       RECORDOID,
>                       -1,
>                       InvalidOid,
>                       varlevelsup);

> the vartype is RECORDOID, but te reltype of src is not RECORDOID, so
> $SUBJECT error reports.

Hmm.  I tried adjusting the example to make _country_or_region
be a materialized view or plain table instead of a view, and
those cases did not fail.  I wonder why the difference...

> I add the below codes to makeWholeRowVar() default branch:
> if (rte->relkind == RELKIND_VIEW)
>         toid = get_rel_type_id(rte->relid);
> else
>         toid = RECORDOID;
> It can work.

I'm quite uncomfortable with the idea of changing makeWholeRowVar()
itself in this way --- the potential blast radius from that seems
rather large.  A localized fix in transform_MERGE_to_join() might
be a wiser answer.

			regards, tom lane



Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Repair commits 317aba70e et al for -DWRITE_READ_PARSE_PLAN_TREES.

  2. Build whole-row Vars the same way during parsing and planning.

  3. Preserve RangeTblEntry.relid when expanding a view RTE.

  4. Fix incorrect non-strict join recheck in MERGE WHEN NOT MATCHED BY SOURCE.