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From: Amit Kapila <amit.kapila16@gmail.com>
Date: Fri, 20 Feb 2026 10:48:28 +0530
Message-ID: <CAA4eK1+Tn+T3qRts6hSqko7oyNiWS1U_mDkXw6+zGhAAde3CZA@mail.gmail.com>
Subject: Re: [PATCH] Support automatic sequence replication
To: Dilip Kumar <dilipbalaut@gmail.com>
Cc: Ajin Cherian <itsajin@gmail.com>, 
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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On Fri, Feb 20, 2026 at 10:11=E2=80=AFAM Dilip Kumar <dilipbalaut@gmail.com=
> wrote:
>
> On Tue, Feb 3, 2026 at 9:18=E2=80=AFAM Ajin Cherian <itsajin@gmail.com> w=
rote:
> >
> > Hello hackers,
> >
> > I'd like to propose an improvement to the sequence replication feature
> > that was committed in [1].
> >
> > The current implementation synchronizes sequences during initial
> > subscription setup, but the sequence sync worker exits after this
> > initial sync. This means that as sequences advance on the publisher,
> > they drift from the subscriber values over time. Users must manually
> > run ALTER SUBSCRIPTION ... REFRESH SEQUENCES to resynchronize, which
> > requires monitoring and intervention.
>
> Thanks, Ajin, for the proposal. I am trying to think: what is the use
> case for automatically updating the sequence values? IIUC, the only
> use case for the sequence sync worker was when using logical
> replication for an upgrade; after the upgrade, you should have
> up-to-date values for the sequences. By adding an automatic update,
> are you targeting any new use case?
>
> If we are still targeting the same use case, I=E2=80=99d like to understa=
nd
> how updating the value at specific intervals will improve the user
> experience.
>

Even for an upgrade, to avoid large downtime, it would be better if
the subscriber has the latest values of sequences, so that during the
upgrade of the publisher, the subscriber can receive all client
requests. It is possible with the REFRESH SEQUENCES command as well
but in the worst case (when there are large number of sequences), it
can take much longer time.

--=20
With Regards,
Amit Kapila.