Re: Adding a '--two-phase' option to 'pg_createsubscriber' utility.

On Thu, 12 Dec 2024 at 08:14, Hayato Kuroda (Fujitsu)
<kuroda(dot)hayato(at)fujitsu(dot)com> wrote:
>
> Dear Shubham,
>
> > Thank you for pointing this out and for suggesting the changes. I
> > agree with your approach.
> > Also, I found a mistake in getopt_long and fixed it in this version of
> > the patch.
> > The attached patch contains the suggested changes.
>
> Thanks for updating the patch. I think the patch looks mostly OK.
>
> Regarding the test code - I think we should directly refer the pg_subscription catalog,
> and confirm that subtwophase is 'p'. IIUC, we can wait until
> all subscriptions. Subtwophasestate are 'e', by using poll_query_until() and [1].
>
> [1]: SELECT count(1) = 0 FROM pg_subscription WHERE subtwophasestate NOT IN ('e');

Yes, that approach is better. Also this is not required after checking
using pg_subscription:
+# Prepare a transaction on the publisher
+$node_p->safe_psql(
+ $db1, qq[
+ BEGIN;
+ INSERT INTO tbl1 SELECT generate_series(1, 10);
+ PREPARE TRANSACTION 'test_prepare';
+]);
+
# Start subscriber
$node_s->start;

+# Verify that the prepared transaction is replicated to the subscriber
+my $count_prepared_s =
+ $node_s->safe_psql($db1, "SELECT count(*) FROM pg_prepared_xacts;");
+
+is($count_prepared_s, qq(1), 'Prepared transaction replicated to subscriber');

Regards,
Vignesh