From 8e58bd9183e743ec5f8ff28897eb78919afd3359 Mon Sep 17 00:00:00 2001 From: Shlok Kyal Date: Sat, 10 May 2025 23:28:09 +0530 Subject: [PATCH v4] Fix duplicate insert during pg_createsubscriber When pg_createsubscriber is run, the standby node is recovered to a point 'consistent_lsn' and promoted. Then, when the subscription is created, the replication origin is advanced to the 'consistent_lsn'. Then the subscription is enabled and the apply worker starts to send changes from 'consistent_lsn'. When this 'consistent_lsn' is an LSN corresponding to a COMMIT, the records for the transaction for that COMMIT are already replicated to the standby node during the recovery phase. Now, when the subscription is created, the replication origin is advanced and the subscription is enabled. The apply worker starts to apply changes from 'consistent_lsn'. So, records corresponding to the transaction whose COMMIT LSN is 'consistent_lsn' are replicated again. To avoid this, set recovery_target_inclusive = false instead of true. So the standby will recovery till point just before 'consistent_lsn'. And apply worker will start(after enabling of subscription) to apply changes from 'consistent_lsn'. So, above scenorio is avoided. --- src/bin/pg_basebackup/pg_createsubscriber.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c index 677c0cd0843..1003c329c73 100644 --- a/src/bin/pg_basebackup/pg_createsubscriber.c +++ b/src/bin/pg_basebackup/pg_createsubscriber.c @@ -1207,7 +1207,7 @@ setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir, const c appendPQExpBuffer(recoveryconfcontents, "recovery_target_timeline = 'latest'\n"); appendPQExpBuffer(recoveryconfcontents, - "recovery_target_inclusive = true\n"); + "recovery_target_inclusive = false\n"); appendPQExpBuffer(recoveryconfcontents, "recovery_target_action = promote\n"); appendPQExpBuffer(recoveryconfcontents, "recovery_target_name = ''\n"); -- 2.34.1