Re: Logical Replication of sequences

On Thu, Oct 16, 2025 at 4:53 PM Zhijie Hou (Fujitsu)
<houzj(dot)fnst(at)fujitsu(dot)com> wrote:
>
> Thanks! Here is the remaining patches, which addressed all pending comments.
>

Few comments on 0001/0003:
========================
1.
@@ -480,7 +480,9 @@ RemoveSubscriptionRel(Oid subid, Oid relid)
* leave tablesync slots or origins in the system when the
* corresponding table is dropped.
*/
- if (!OidIsValid(subid) && subrel->srsubstate != SUBREL_STATE_READY)
+ if (!OidIsValid(subid) &&
+ get_rel_relkind(subrel->srrelid) != RELKIND_SEQUENCE &&
+ subrel->srsubstate != SUBREL_STATE_READY)
{

Here, why don't we allow sequence rel to be removed? Please add some comments.

2.
/*
* Get the relations for the subscription.
*
- * If not_ready is true, return only the relations that are not in a ready
- * state, otherwise return all the relations of the subscription. The
- * returned list is palloc'ed in the current memory context.
+ * get_tables: get relations for tables of the subscription.
+ *
+ * get_sequences: get relations for sequences of the subscription.
+ *
+ * not_ready:
+ * If getting tables and not_ready is false, retrieve all tables;
+ * otherwise, retrieve only tables that have not reached the READY state.
+ * If getting sequences and not_ready is false, retrieve all sequences;
+ * otherwise, retrieve only sequences that have not reached the READY state.
+ *
+ * The returned list is palloc'ed in the current memory context.
*/
List *
-GetSubscriptionRelations(Oid subid, bool not_ready)
+GetSubscriptionRelations(Oid subid, bool get_tables, bool get_sequences,
+ bool not_ready)

The existing code comments (without the patch) are good enough for this change.

3. Move catalogs.sgml, alter_subscription.sgml (parts related to 0001)
from 0003 to 0001. Also, see if anything else can be moved.

4.
<para>
- Fetch missing table information from publisher. This will start
+ Fetch missing table information from the publisher. This will start
replication of tables that were added to the subscribed-to publications
since <link linkend="sql-createsubscription">
<command>CREATE SUBSCRIPTION</command></link> or
the last invocation of <command>REFRESH PUBLICATION</command>.
</para>

+ <para>
+ Also, fetch missing sequence information from the publisher.
+ </para>

The second para should be merged into the first one: Fetch missing
table and sequence information from the publisher.

5.
+ </para>
+ <para>
+ State codes for sequences:
+ <literal>i</literal> = initialize,
+ <literal>d</literal> = re-synchronize,
+ <literal>r</literal> = ready
</para></entry>

I think we need to remove the 'd' state from here as the patch 0001
changes always update the sequence state to init.

--
With Regards,
Amit Kapila.