Re: REPACK (CONCURRENTLY) fails when replica identity index is dropped

On 2026-Sep-01, Alvaro Herrera wrote:

> On 2026-Sep-01, Antonin Houska wrote:
>
> > I agree that the core issue is that we allow dropping an index that is being
> > used as replica identity.
> >
> > Regarding catalog entries already broken this way, it appears that pg_upgrade
> > fixes them because pg_dump does not issue "ALTER TABLE ... REPLICA IDENTITY
> > USING INDEX ..." if there is not identity index. Thus after pg_restore,
> > pg_class(relreplident) becomes REPLICA_IDENTITY_DEFAULT.
>
> I agree that disallowing the drop is a sensible thing to do.

Actually, wouldn't it make more sense to reset the replica identity back
to 'd' when the index is dropped, as in the attached patch?

--
Álvaro Herrera 48°01'N 7°57'E — https://www.EnterpriseDB.com/
"After a quick R of TFM, all I can say is HOLY CR** THAT IS COOL! PostgreSQL was
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Berend Tober, http://archives.postgresql.org/pgsql-hackers/2007-08/msg01009.php