UNLISTEN
UNLISTEN — stop listening for a notification
Synopsis
UNLISTEN { channel
| * }
Description
UNLISTEN
is used to remove an existing registration for NOTIFY
events. UNLISTEN
cancels any existing registration of the current Postgres Pro session as a listener on the notification channel named channel
. The special wildcard *
cancels all listener registrations for the current session.
NOTIFY contains a more extensive discussion of the use of LISTEN
and NOTIFY
.
Parameters
channel
Name of a notification channel (any identifier).
*
All current listen registrations for this session are cleared.
Notes
You can unlisten something you were not listening for; no warning or error will appear.
At the end of each session, UNLISTEN *
is automatically executed.
A transaction that has executed UNLISTEN
cannot be prepared for two-phase commit.
Examples
To make a registration:
LISTEN virtual; NOTIFY virtual; Asynchronous notification "virtual" received from server process with PID 8448.
Once UNLISTEN
has been executed, further NOTIFY
messages will be ignored:
UNLISTEN virtual; NOTIFY virtual; -- no NOTIFY event is received
Compatibility
There is no UNLISTEN
command in the SQL standard.