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Yes, PostgreSQL does support concurrent WAL replay and read query execution= on replicas through its hot standby feature. By setting hot_standby =3D on= , a replica can serve read-only queries while applying WAL files from the p= rimary via streaming replication. However, there are a few caveats: * Read queries on the standby may be canceled if they conflict with rec= overy operations. This behavior can be tuned using parameters like max_stan= dby_streaming_delay and hot_standby_feedback. * Unlike Oracle GoldenGate, PostgreSQL=92s native logical replication i= s more limited in terms of conflict resolution and cross-version replicatio= n, though tools like pglogical or Debezium can bridge those gaps for more c= omplex use cases. Best regards, David Okeamah DAVID OKEAMAH,DEVELOPER ________________________________ From: Wasim Devale Sent: Friday, May 23, 2025 8:13:10 AM To: pgsql-admin ; Pgsql-admin Subject: Replication lag Hello, Reply wal and query execution on replica can coexists? Golden gate in oracle has this feature that they can coexists but in postgr= esql do we have any provision like this. Please assist. Thanks, Wasim --_000_AS4PR03MB8506AFDDDE719261B0E1ADDDF798AAS4PR03MB8506eurp_ Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable

Query Execution and Reply WAL Coexistence in PostgreSQL


 Wasim,





  • Read queries on the standby may be canceled if they conflict with recovery = operations. This behavior can be tuned using parameters like max_standby_st= reaming_delay and hot_standby_feedback.
  • Unlike Oracle GoldenGate, PostgreSQL=92s native logical replication is more= limited in terms of conflict resolution and cross-version replication, tho= ugh tools like pglogical or Debezium can bridge those gaps for more complex= use cases.






DAVID OKEAMAH,DEVELOPER 
From: Wasim Devale <wasi= md60@gmail.com>
Sent: Friday, May 23, 2025 8:13:10 AM
To: pgsql-admin <pgsql-admin@postgresql.org>; Pgsql-admin <= pgsql-admin@lists.postgresql.org>
Subject: Replication lag
 
Hello,

Reply wal and query execution on replica can coexists?

Golden gate in oracle has this feature that they can coex= ists but in postgresql do we have any provision like this.

Please assist.

Thanks,
Wasim
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