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<title>UNLISTEN</title>
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<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry" lang="en">
<a name="sql-unlisten"></a><div class="titlepage"></div>
<div class="refnamediv">
<h2>Name</h2>
<p>UNLISTEN — stop listening for a notification</p>
</div>
<a name="id789915"></a><div class="refsynopsisdiv">
<h2>Synopsis</h2>
<pre class="synopsis">UNLISTEN { <em class="replaceable"><code>name</code></em> | * }</pre>
</div>
<div class="refsect1" lang="en">
<a name="id789938"></a><h2>Description</h2>
<p> <code class="command">UNLISTEN</code> is used to remove an existing
registration for <code class="command">NOTIFY</code> events.
<code class="command">UNLISTEN</code> cancels any existing registration of
the current <span class="productname">PostgreSQL</span> session as a
listener on the notification <em class="replaceable"><code>name</code></em>. The special wildcard
<code class="literal">*</code> cancels all listener registrations for the
current session.
</p>
<p> <a href="sql-notify.html">NOTIFY</a>
contains a more extensive
discussion of the use of <code class="command">LISTEN</code> and
<code class="command">NOTIFY</code>.
</p>
</div>
<div class="refsect1" lang="en">
<a name="id790015"></a><h2>Parameters</h2>
<div class="variablelist"><dl>
<dt><span class="term"><em class="replaceable"><code>name</code></em></span></dt>
<dd><p> Name of a notification (any identifier).
</p></dd>
<dt><span class="term"><code class="literal">*</code></span></dt>
<dd><p> All current listen registrations for this session are cleared.
</p></dd>
</dl></div>
</div>
<div class="refsect1" lang="en">
<a name="id790045"></a><h2>Notes</h2>
<p> You may unlisten something you were not listening for; no warning or error
will appear.
</p>
<p> At the end of each session, <code class="command">UNLISTEN *</code> is
automatically executed.
</p>
</div>
<div class="refsect1" lang="en">
<a name="id790063"></a><h2>Examples</h2>
<p> To make a registration:
</p>
<pre class="programlisting">LISTEN virtual;
NOTIFY virtual;
Asynchronous notification "virtual" received from server process with PID 8448.</pre>
<p>
</p>
<p> Once <code class="command">UNLISTEN</code> has been executed, further <code class="command">NOTIFY</code>
commands will be ignored:
</p>
<pre class="programlisting">UNLISTEN virtual;
NOTIFY virtual;
-- no NOTIFY event is received</pre>
<p>
</p>
</div>
<div class="refsect1" lang="en">
<a name="id790103"></a><h2>Compatibility</h2>
<p> There is no <code class="command">UNLISTEN</code> command in the SQL standard.
</p>
</div>
<div class="refsect1" lang="en">
<a name="id790117"></a><h2>See Also</h2>
<span class="simplelist"><a href="sql-listen.html">LISTEN</a>, <a href="sql-notify.html">NOTIFY</a></span>
</div>
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