Re: Logical Replication of sequences

Hi Vignesh,

Some review comments patch V20251029-0001 (the test code only)

======
src/test/subscription/t/036_sequences.pl

1.
+##########
+## ALTER SUBSCRIPTION ... REFRESH PUBLICATION with (copy_data = off) should
+# not update the sequence values for the new sequence.
+##########
+
+# Create a new sequence 'regress_s4'
+$node_publisher->safe_psql(
+ 'postgres', qq(
+ CREATE SEQUENCE regress_s4;
+ INSERT INTO regress_seq_test SELECT nextval('regress_s4') FROM
generate_series(1,100);
+));
+

AFAICT the sequence `regress_s3` (from the previous test part) was
already a "new sequence" that had not yet been REFRESHED to the
subscriber. So I think maybe there wasn't any need to create another
sequence `regress_s4` for this test part.

~~~

2.
+# Check - newly published sequence values are not updated
+$result = $node_subscriber->safe_psql(
+ 'postgres', qq(
+ SELECT last_value, log_cnt, is_called FROM regress_s4;
+));

Maybe that comment can give more details:
# Check - newly published sequence values are not updated when (copy_data = off)

~~~

3.
+##########
+# ALTER SUBSCRIPTION ... REFRESH PUBLICATION should report an error when:
+# a) sequence definitions differ between the publisher and subscriber, or
+# b) a sequence is missing on the publisher.
+##########

OK, you have these mismatch parameters and missing sequences test for
"REFRESH PUBLICATION", but what about doing the same tests for
"REFRESH SEQUENCES" -- e,g, I am thinking you can ALTER/DROP some
publication that previously had synchronized OK, to verify what
happens during "REFRESH SEQUENCES".

======
Kind Regards,
Peter Smith.
Fujitsu Australia