Re: Proposal: Conflict log history table for Logical Replication

On Thu, 27 Nov 2025 at 17:50, Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
>
> On Thu, Nov 27, 2025 at 6:30 AM Peter Smith <smithpb2250(at)gmail(dot)com> wrote:
>
> I have fixed all these comments and also the comments of 0002, now I
> feel we can actually merge 0001 and 0002, so I have merged both of
> them.

I just started to have a look at the patch, while using I found lock
level used is not correct:
I felt the reason is that table is opened with RowExclusiveLock but
closed in AccessExclusiveLock:

+ /* If conflict log table is not set for the subscription just return. */
+ conflictlogtable = get_subscription_conflict_log_table(
+
MyLogicalRepWorker->subid, &nspid);
+ if (conflictlogtable == NULL)
+ {
+ pfree(conflictlogtable);
+ return NULL;
+ }
+
+ conflictlogrelid = get_relname_relid(conflictlogtable, nspid);
+ if (OidIsValid(conflictlogrelid))
+ conflictlogrel = table_open(conflictlogrelid, RowExclusiveLock);

....
+ if (elevel < ERROR)
+ InsertConflictLogTuple(conflictlogrel);
+
+ table_close(conflictlogrel, AccessExclusiveLock);
....

2025-11-28 12:17:55.631 IST [504133] WARNING: you don't own a lock of
type AccessExclusiveLock
2025-11-28 12:17:55.631 IST [504133] CONTEXT: processing remote data
for replication origin "pg_16402" during message type "INSERT" for
replication target relation "public.t1" in transaction 761, finished
at 0/01789AB8
2025-11-28 12:17:58.033 IST [504133] WARNING: you don't own a lock of
type AccessExclusiveLock
2025-11-28 12:17:58.033 IST [504133] ERROR: conflict detected on
relation "public.t1": conflict=insert_exists
2025-11-28 12:17:58.033 IST [504133] DETAIL: Key already exists in
unique index "t1_pkey", modified in transaction 766.
Key (c1)=(1); existing local row (1, 1); remote row (1, 1).
2025-11-28 12:17:58.033 IST [504133] CONTEXT: processing remote data
for replication origin "pg_16402" during message type "INSERT" for
replication target relation "public.t1" in transaction 761, finished
at 0/01789AB8

Regards,
Vignesh