unlisten(7) [centos man page]

UNLISTEN(7)						  PostgreSQL 9.2.7 Documentation					       UNLISTEN(7)

NAME

       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
       PostgreSQL session as a listener on the notification channel named channel. The special wildcard * cancels all listener registrations for
       the current session.

       NOTIFY(7) 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.

SEE ALSO

       LISTEN(7), NOTIFY(7)

PostgreSQL 9.2.7						    2014-02-17							       UNLISTEN(7)

UNLISTEN(7)							   SQL Commands 						       UNLISTEN(7)

NAME

       UNLISTEN - stop listening for a notification

SYNOPSIS

       UNLISTEN { notifyname | * }

   INPUTS
       notifyname
	      Name of previously registered notify condition.

       *      All current listen registrations for this backend are cleared.

   OUTPUTS
       UNLISTEN
	      Acknowledgment that statement has executed.

DESCRIPTION

       UNLISTEN  is  used to remove an existing NOTIFY registration.  UNLISTEN cancels any existing registration of the current PostgreSQL session
       as a listener on the notify condition notifyname.  The special condition wildcard * cancels all listener registrations for the current ses-
       sion.

       NOTIFY [notify(7)] contains a more extensive discussion of the use of LISTEN and NOTIFY.

   NOTES
       notifyname need not be a valid class name but can be any string valid as a name up to 64 characters long.

       The  backend  does  not	complain if you unlisten something you were not listening for.	Each backend will automatically execute UNLISTEN *
       when exiting.

USAGE

       To subscribe to an existing registration:

       LISTEN virtual;
       LISTEN
       NOTIFY virtual;
       NOTIFY
       Asynchronous NOTIFY 'virtual' from backend with pid '8448' received

       Once UNLISTEN has been executed, further NOTIFY commands will be ignored:

       UNLISTEN virtual;
       UNLISTEN
       NOTIFY virtual;
       NOTIFY
       -- notice no NOTIFY event is received

COMPATIBILITY

   SQL92
       There is no UNLISTEN in SQL92.

SQL - Language Statements					    2002-11-22							       UNLISTEN(7)