Re: Logical Replication of sequences

Ajin Cherian <itsajin@gmail.com>

From: Ajin Cherian <itsajin@gmail.com>

To: vignesh C <vignesh21@gmail.com>

Cc: shveta malik <shveta.malik@gmail.com>, Peter Smith <smithpb2250@gmail.com>, Nisha Moond <nisha.moond412@gmail.com>, "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>, Masahiko Sawada <sawada.mshk@gmail.com>, Shlok Kyal <shlok.kyal.oss@gmail.com>, Amit Kapila <amit.kapila16@gmail.com>, Peter Eisentraut <peter@eisentraut.org>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Euler Taveira <euler@eulerto.com>, Michael Paquier <michael@paquier.xyz>, "Zhijie Hou (Fujitsu)" <houzj.fnst@fujitsu.com>, "Jonathan S. Katz" <jkatz@postgresql.org>

Date: 2025-05-29T05:59:51Z

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 Fri, May 23, 2025 at 3:12 AM vignesh C <vignesh21@gmail.com> wrote:

>
>
> The attached v20250522 patch has the changes for the same.
>
> Regards,
> Vignesh
>

Some review comments for patch 0001:
1. In src/backend/commands/sequence.c
in pg_sequence_state()
+ /* open and lock sequence */
+ init_sequence(seq_relid, &elm, &seqrel);
+
+ if (pg_class_aclcheck(elm->relid, GetUserId(),
+  ACL_SELECT | ACL_USAGE) != ACLCHECK_OK)
+ ereport(ERROR,
+ errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+ errmsg("permission denied for sequence %s",
+   RelationGetRelationName(seqrel)));
+

How about using aclcheck_error for this, which also supports error messages
for specific access errors. Most other objects seem to be using this.
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, get_relkind_objtype(seqrel->relkind),
  RelationGetRelationName(seqrel));

2. in function pg_sequence_state()
+
+ UnlockReleaseBuffer(buf);
+ relation_close(seqrel, NoLock);

Ideally the corresponding close for init_sequence is sequence_close()
rather than relation_close()

I will post comments for the other patches as well.

regards,
Ajin Cherian
Fujitsu Australia