PostgreSQL 7.3.4 Documentation
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# UNLISTEN

## 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 session.

NOTIFY 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.

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