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