Re: logical decoding and replication of sequences, take 2

On Sun, Dec 3, 2023 at 11:56 PM Tomas Vondra
<tomas.vondra@enterprisedb.com> wrote:
>
> On 12/3/23 18:52, Tomas Vondra wrote:
> > ...
> >
>
> Another idea is that maybe we could somehow inform ReorderBuffer whether
> the output plugin even is interested in sequences. That'd help with
> cases where we don't even want/need to replicate sequences, e.g. because
> the publication does not specify (publish=sequence).
>
> What happens now in that case is we call ReorderBufferQueueSequence(),
> it does the whole dance with starting/aborting the transaction, calls
> rb->sequence() which just does "meh" and doesn't do anything. Maybe we
> could just short-circuit this by asking the output plugin somehow.
>
> In an extreme case the plugin may not even specify the sequence
> callbacks, and we're still doing all of this.
>

We could explore this but I guess it won't solve the problem we are
facing in cases where all sequences are published and plugin has
specified the sequence callbacks. I think it would add some overhead
of this check in positive cases where we decide to anyway do send the
changes.

--
With Regards,
Amit Kapila.