Description

The WAITLSN wait till target LSN will be replayed with an optional “delay” (milliseconds by default infinity) to be wait for LSN to replayed.

WAITLSN provides a simple interprocess LSN wait mechanism for a backends on slave in master-slave replication scheme on Postgres Pro database.

Parameters

Notes

Delay time to waiting for LSN to be replayed must be integer. For default it is infinity. Waiting can be interrupted using Ctl+C, or by Postmaster death.

Examples

Configure and execute a waitlsn from psql:

WAITLSN '0/3F07A6B1', 10000;
NOTICE:  LSN is not reached. Try to make bigger delay.
WAITLSN

WAITLSN '0/3F07A611';
WAITLSN

WAITLSN '0/3F0FF791', 500000;
^CCancel request sent
NOTICE:  LSN is not reached. Try to make bigger delay.
ERROR:  canceling statement due to user request

Compatibility

There is no WAITLSN statement in the SQL standard.