Re: [HACKERS] MERGE SQL Statement for PG11

On Sat, Mar 24, 2018 at 5:27 AM, Robert Haas <robertmhaas@gmail.com> wrote:
> If it's possible to identify the two OIDs that are supposed to match
> and cross-check that the OIDs are the same, then we could just bomb
> out with an error if they aren't.  That's not lovely, and is basically
> a hack, but it's possible that no better fix is possible in the time
> we have, and it's wouldn't be any worse than this crock from copy.c:
>
>             if (!list_member_oid(plan->relationOids, queryRelId))
>                 ereport(ERROR,
>                         (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
>                          errmsg("relation referenced by COPY statement
> has changed")));

That's definitely all we have time for. The only alternative is to rip
out support for partitioning, as partitioning is the only thing that
necessitates the use of multiple RTEs. I don't think it would make
sense to use a second RTE only when needed.

-- 
Peter Geoghegan