UNLISTEN

UNLISTEN

UNLISTEN

7

SQL - Language Statements

UNLISTEN

stop listening for a notification

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.

??? 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#