WAITLSN — wait for the target LSN to be replayed
WAITLSN'LSN'[ ,wait_time]
WAITLSN provides a simple
interprocess communication mechanism to wait for the target log sequence
number (LSN) on standby in Postgres Pro
databases with master-standby asynchronous replication. When run with the
LSN option, the WAITLSN command
waits for the specified LSN to be replayed. By default, wait
time is unlimited. Waiting can be interrupted using Ctrl+C, or
by shutting down the postgres server. You can also limit the wait
time specifying the wait_time option, in milliseconds.
LSNSpecify the target log sequence number to wait for.
wait_time
Limit the time to wait for the LSN to be replayed.
The specified wait_time must be an integer
and is measured in milliseconds.
Run WAITLSN from psql,
limiting wait time to 10000 milliseconds:
WAITLSN '0/3F07A6B1', 10000; NOTICE: LSN is not reached. Try to make bigger delay. WAITLSN
Wait until the specified LSN is replayed:
WAITLSN '0/3F07A611'; WAITLSN ------------- t (1 row)
Limit LSN wait time to 500000 milliseconds, and then cancel the command:
WAITLSN '0/3F0FF791', 500000; ^CCancel request sent NOTICE: LSN is not reached. Try to make bigger delay. ERROR: canceling statement due to user request
There is no WAITLSN statement in the SQL
standard.