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. 

