Re: pg_class.reltuples of brin indexes - Mailing list pgsql-hackers

On Sun, Dec 31, 2023 at 02:08:41AM +0100, Tomas Vondra wrote:
> I'm not sure. I think the current behavior is (still) wrong - I just
> rediscovered it during testing BRIN. I haven't checked, but I guess GIN
> is still affected too.
>
> What's not clear to me is if this is merely cosmetic issue (making
> pg_class data confusing for people), or if it has some practical impact.
> And I'm not sure there's a good way to improve this, except for some
> basic guesswork. For BRIN I can imagine simply calculating the number of
> page ranges (relpages / pages_per_range), but no idea about GIN.

FWIW, this area of the code rings a few bells:
https://www.postgresql.org/message-id/17787-b2dbe62bdfabd467@postgresql.org
https://www.postgresql.org/message-id/17205-42b1d8f131f0cf97@postgresql.org
--
Michael