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From: Peter Smith <smithpb2250@gmail.com>
Date: Thu, 25 Jun 2026 12:58:57 +1200
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Subject: Re: Include sequences in publications created by pg_createsubscriber
To: vignesh C <vignesh21@gmail.com>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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Hi Vignesh.

Some comments for v2.

======
doc/src/sgml/ref/pg_createsubscriber.sgml

1.
    fresh logical replication setup.  The main difference between the logical
    replication setup and <application>pg_createsubscriber</application> is how
    the data synchronization is done.
<application>pg_createsubscriber</application>
-   does not copy the initial table data. It does only the
synchronization phase,
-   which ensures each table is brought up to a synchronized state.
+   does not copy the initial table or sequence data. It does only the
+   synchronization phase, which ensures each table and sequence is brought up
+   to a synchronized state.

1a.
OK. Thanks for the explanation on what was meant. Personally, I found
the wording "sequence is brought up to a synchronized state"
ambiguous, because in my mind the sequence value is a part of the
sequence state.

Below is some alternate wording for consideration:

SUGGESTION:
pg_createsubscriber performs only the synchronization phase, which
prepares each table and sequence for replication. It does not copy
table data or synchronize sequence values from the publisher.

~~~

1b.
While reviewing this patch I also referred to section "29.7.
Replicating Sequences #". [1] for more information. But there I was
tricked by some (misleading?) wording.
I have created another thread [2] to discuss/patch that. Please see it
and post your thoughts.

~~~

2.
+  <para>
+   Note that although the publication includes sequences, sequence value
+   changes made on the publisher after reaching consistent point are not
+   synchronized incrementally. To synchronize sequence values, run
+   <link linkend="sql-altersubscription-params-refresh-sequences">
+   <command>ALTER SUBSCRIPTION ... REFRESH SEQUENCES</command></link>, which
+   fetches the current sequence state from the publisher and advances the
+   corresponding subscriber sequences.
   </para>

I wonder if the last sentence is overly descriptive. Isn't it enough
to just say:
To synchronize sequence values, run <link
linkend="sql-altersubscription-params-refresh-sequences"><command>ALTER
SUBSCRIPTION ... REFRESH SEQUENCES</command></link>.

~~~

3.
      <para>
       Enable the subscription for each specified database on the target server.
       The subscription starts applying transactions from the replication start
-      point.
+      point. The subscription is configured to include sequences.
      </para>

This implies there was some special subscription "configuration" for
getting sequences, but it just gets sequences because sequences were
published. Maybe you don't need to say anything here. Or, maybe reword
to just say "The subscription will include sequences".

======
[1] https://www.postgresql.org/docs/19/logical-replication-sequences.html#LOGICAL-REPLICATION-SEQUENCES
[2] https://www.postgresql.org/message-id/CAHut%2BPsrVntfrJ8gV45%2B6%3D1bs5dTWD5mU7Q6aKrBnf1vmyZQkQ%40mail.gmail.com

Kind Regards,
Peter Smith.
Fujitsu Australia