Re: [PoC] pg_upgrade: allow to upgrade publisher node

On Mon, Aug 21, 2023 at 6:35 PM Hayato Kuroda (Fujitsu)
<kuroda.hayato@fujitsu.com> wrote:
>
> > 9. check_for_logical_replication_slots
> >
> > + /* logical replication slots can be migrated since PG17. */
> > + if (GET_MAJOR_VERSION(new_cluster->major_version) <= 1600)
> > + return;
> >
> > IMO the code matches the comment better if you say < 1700 instead of <= 1600.
>
> Changed.
>

I think it is better to be consistent with the existing code. There
are a few other checks in pg_upgrade.c that uses <=, so it is better
to use it in the same way here.

Another minor comment:
Note that
+     if the new cluser uses different port number from old one,
+     <link linkend="sql-altersubscription"><command>ALTER
SUBSCRIPTION ... CONNECTION</command></link>
+     command must be also executed on subscriber.

I think this is true in general as well and not specific to
pg_upgrade. So, we can avoid adding anything about connection change
here.

--
With Regards,
Amit Kapila.