Re: Logical Replication - behavior of ALTER PUBLICATION .. DROP TABLE and ALTER SUBSCRIPTION .. REFRESH PUBLICATION

On Wed, Jan 13, 2021 at 2:36 PM japin <japinli@hotmail.com> wrote:
> > In summary, I feel we need to fix the publisher sending the inserts
> > even though the table is dropped from the publication, that is the
> > patch patch proposed by japin. This solves the bug reported in this
> > thread.
> >
> > And also, it's good to have the LogicalRepRelMap invalidation fix as a
> > 0002 patch in invalidate_syncing_table_states, subscription_change_cb
> > and logicalrep_rel_open as proposed by me.
> >
> > Thoughts?
> >
>
> I think invalidate the LogicalRepRelMap is necessary.  If the table isn't in
> subscription, can we remove the LogicalRepRelMapEntry from LogicalRepRelMap?

IIUC, it's not possible to know the relid of the alter
publication...dropped table in the invalidation callbacks
invalidate_syncing_table_states or subscription_change_cb, so it's
better to set state of all the entries to SUBREL_STATE_UNKNOWN, so
that, in the next logicalrep_rel_open call the function
GetSubscriptionRelState will be called and the pg_subscription_rel
will be read freshly.

This is inline with the reasoning specified at [1].

[1] - https://www.postgresql.org/message-id/CAFiTN-udwuc_h0TaFrSEKb-Yo1vVvkjz9TDRw7VE3P-KiPSGbQ%40mail.gmail.com

With Regards,
Bharath Rupireddy.
EnterpriseDB: http://www.enterprisedb.com