RE: Logical Replication of sequences

Zhijie Hou (Fujitsu) <houzj.fnst@fujitsu.com>

From: "Zhijie Hou (Fujitsu)" <houzj.fnst@fujitsu.com>

To: vignesh C <vignesh21@gmail.com>, Amit Kapila <amit.kapila16@gmail.com>

Cc: Masahiko Sawada <sawada.mshk@gmail.com>, "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>, Dilip Kumar <dilipbalaut@gmail.com>, Peter Smith <smithpb2250@gmail.com>, shveta malik <shveta.malik@gmail.com>, Shlok Kyal <shlok.kyal.oss@gmail.com>, Chao Li <li.evan.chao@gmail.com>, Nisha Moond <nisha.moond412@gmail.com>, Peter Eisentraut <peter@eisentraut.org>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Euler Taveira <euler@eulerto.com>, Michael Paquier <michael@paquier.xyz>, "Jonathan S. Katz" <jkatz@postgresql.org>

Date: 2025-10-24T03:25:49Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Doc: Add documentation for sequence synchronization.
- 55cefadde874 19 (unreleased) landed
Remove unused assignment in CREATE PUBLICATION grammar.
- bfb7419b0bbe 19 (unreleased) landed
Add seq_sync_error_count to subscription statistics.
- f6a4c498dcf6 19 (unreleased) landed
Fix few issues in commit 5509055d69.
- 5a4eba558aa7 19 (unreleased) landed
Add sequence synchronization for logical replication.
- 5509055d6956 19 (unreleased) landed
Add worker type argument to logical replication worker functions.
- 3e8e05596a02 19 (unreleased) landed
Introduce "REFRESH SEQUENCES" for subscriptions.
- f0b3573c3aac 19 (unreleased) landed
Refactor logical worker synchronization code into a separate file.
- 41c674d2e31e 19 (unreleased) landed
Standardize use of REFRESH PUBLICATION in code and messages.
- 2436b8c047ff 19 (unreleased) landed
Add "ALL SEQUENCES" support to publications.
- 96b378497346 19 (unreleased) landed
Expose sequence page LSN via pg_get_sequence_data.
- b93172ca59f4 19 (unreleased) landed
Resume conflict-relevant data retention automatically.
- 0d48d393d465 19 (unreleased) cited
Post-commit review fixes for 228c370868.
- 1f7e9ba3ac4e 19 (unreleased) cited
Generate GUC tables from .dat file
- 63599896545c 19 (unreleased) cited

On Thursday, October 23, 2025 2:15 PM vignesh C <vignesh21@gmail.com> wrote:
> The attached patch has the changes for the same.
> I have also addressed the other comments: a) Shveta's comments at [1]
> b) Peter's comments at [2] & [3] c) Shveta's 2nd patch comments at [4] and d)
> Chao's comment#12 from [5] which was pending.

Thanks for updating the patch, I have a few comments for 0002.

1.

+		hash_seq_init(&hash_seq, sequences_to_copy);
+		while ((seq_entry = hash_seq_search(&hash_seq)) != NULL)
+		{
+			pfree(seq_entry->seqname);
+			pfree(seq_entry->nspname);
+		}
+	}
+
+	hash_destroy(sequences_to_copy);

I personally feel these memory free calls are unnecessary since the sync worker
will stop soon.


2.
-FinishSyncWorker(void)
+FinishSyncWorker(LogicalRepWorkerType wtype)

Can we directly access MyLogicalRepWorker->type instead of adding
one func parameter ?


3.

						 "ORDER BY s.schname, s.seqname\n",

Just to confirm, is this "ORDER BY" necessary for correctness ?


4.

		elog(LOG, "skip synchronization of sequence \"%s.%s\" because it has been dropped concurrently",
			 nspname, seqname);

Shall we use ereport here ?

Best Regards,
Hou zj