Note: The following description applies both to Postgres-XC and PostgreSQL if not described explicitly. You can read PostgreSQL as Postgres-XC except for version number, which is specific to each product.
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 contains a more extensive discussion of the use of LISTEN and NOTIFY.
Note: XCONLY: The following description applies only to Postgres-XC.
In Postgres-XC, UNLISTEN removes only local NOTIFY events. It does not remove events issued at different coordinators.
Note: The following description applies both to Postgres-XC and PostgreSQL if not described explicitly. You can read PostgreSQL as Postgres-XC except for version number, which is specific to each product.
Name of a notification channel (any identifier).
All current listen registrations for this session are cleared.
Note: The following description applies both to Postgres-XC and PostgreSQL if not described explicitly. You can read PostgreSQL as Postgres-XC except for version number, which is specific to each product.
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.
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