Horton

Re: Conflict detection for update_deleted in logical replication

shveta malik <shveta.malik@gmail.com>

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From: shveta malik <shveta.malik@gmail.com>
To: "Zhijie Hou (Fujitsu)" <houzj.fnst@fujitsu.com>
Cc: Amit Kapila <amit.kapila16@gmail.com>, vignesh C <vignesh21@gmail.com>, Masahiko Sawada <sawada.mshk@gmail.com>, Nisha Moond <nisha.moond412@gmail.com>, "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>, pgsql-hackers <pgsql-hackers@postgresql.org>, shveta malik <shveta.malik@gmail.com>
Date: 2025-06-23T08:41:45Z
Lists: pgsql-hackers 
>
> Here is the V39 patch set which includes the following changes:
>

Few trivial comments:

1)
Currently we have this error and detail:

ERROR:  Enabling retain_conflict_info requires "wal_level" >= "replica"
DETAIL:  A replication slot must be created to retain conflict information.

Shall we change it to something like:

msg: "wal_level is insufficient to create slot required by retain_conflict_info"
hint: "wal_level must be set to replica or logical at server start"

2)

+   <para>
+    Note that commit timestamps and origin data are not preserved during the
+    upgrade. Consequently, even with
+    <link linkend="sql-createsubscription-params-with-retain-conflict-info"><literal>retain_conflict_info</literal></link>
+    enabled, the upgraded subscriber might be unable to detect conflicts or log
+    relevant commit timestamps and origins when applying changes from the
+    publisher occurring before or during the upgrade. To prevent this
issue, the
+    user must ensure that all potentially conflicting changes are fully
+    replicated to the subscriber before proceeding with the upgrade.
+   </para>

Shall we have a NOTE tag here? This page has existing NOTE and WARNING
tags for similar situations where we are advising something to users?

thanks
Shveta

Commits

  1. Fix intermittent BF failures in 035_conflicts.

  2. Resume conflict-relevant data retention automatically.

  3. Fix intermittent test failure introduced in 6456c6e2c4.

  4. Fix Coverity issue reported in commit a850be2fe.

  5. Add test to prevent premature removal of conflict-relevant data.

  6. Post-commit review fixes for 228c370868.

  7. Add max_retention_duration option to subscriptions.

  8. Detect and report update_deleted conflicts.

  9. Preserve conflict-relevant data during logical replication.

  10. Integrate FullTransactionIds deeper into two-phase code

  11. Improve checks for GUC recovery_target_timeline

  12. Prevent excessive delays before launching new logrep workers.

  13. Keep WAL segments by slot's last saved restart LSN

  14. Rework some code handling pg_subscription data in psql and pg_dump

  15. Use generateClonedIndexStmt to propagate CREATE INDEX to partitions.