Re: BUG #19338: [PG15] Unstable SQL result in test regress/tablespace

Dmitry Kovalenko <d.kovalenko@postgrespro.ru>

From: Dmitry Kovalenko <d.kovalenko@postgrespro.ru>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-bugs@lists.postgresql.org
Date: 2025-12-01T16:52:47Z
Lists: pgsql-bugs
Tom,

This test worked on the VM with 4GB memory, 2 cores and AltLinux-10 that 
is hosted on  ARM where are worked lots of other VMs.

I do not know why this select returns wrong order but do not want to see 
this problem again.

I think, we see a prove of unstable order of SELECT without ORDER BY 
clause )

Regards,

Dmitry Kovalenko

01.12.2025 18:54, Tom Lane пишет:
> PG Bug reporting form <noreply@postgresql.org> writes:
>> PG15 has an unstable SQL in test regress/tablespace:
> I tried to reproduce this, without much success.  For me, that
> query gives the same EXPLAIN plan and the same results with
> or without ORDER BY.  (It chooses an indexscan that'd naturally
> order the results.)  And the v15 regression tests pass fine in
> a few different locales I tried, which doesn't surprise me
> given the lack of prior complaints.
>
> In short, I think there's more going on here than meets the eye.
> Can you give a recipe for reproducing this failure?
>
> 			regards, tom lane