Re: BUG #18261: Inconsistent results of SELECT affected by joined subqueries - Mailing list pgsql-bugs

On Mon, Jan 8, 2024 at 3:10 PM Alexander Korotkov <aekorotkov@gmail.com> wrote:
> On Mon, Jan 8, 2024 at 2:49 PM Alexander Korotkov <aekorotkov@gmail.com> wrote:
> > On Mon, Jan 8, 2024, 13:51 Richard Guo <guofenglinux@gmail.com> wrote:
> >> On Fri, Jan 5, 2024 at 11:32 AM Andrei Lepikhov <a.lepikhov@postgrespro.ru> wrote:
> >>>
> >>> The regression test shows where two fully equal join clauses, applied on
> >>> different join levels, differ by the only required_relids. It covers the
> >>> problem and can be helpful by itself. IMO, one line in this test is
> >>> redundant (see attachment).
> >>
> >>
> >> Hmm, I don't think the insert statement in the test case is redundant.
> >> It's needed to verify that the query in the test case gives the correct
> >> result.  Without the insert statement, the wrong plan would give the
> >> same result as the correct plan, i.e., an empty set in this case.
> >>
> >> IMO, if we make some code changes and add a test case for that, we need
> >> to ensure the test can give a different (and correct of course) result
> >> than what came before.
> >
> > Thank you for pointing this.  Yes, veryfying query result not just plan is strengthening the test.  I'll recheck
thisand push the fix later today. 
>
> Pushed.  Thanks again, Richard.

I also noticed my indent oversight.  Will fix that later today.

https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=koel&dt=2024-01-08%2014%3A19%3A03

------
Regards,
Alexander Korotkov