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doc/src/sgml/ref/alter_trigger.sgml

+<!--
+PostgreSQL documentation
+-->
+
+<refentry id="SQL-ALTERTRIGGER">
+ <refmeta>
+  <refentrytitle id="sql-altertrigger-title">
+   ALTER TRIGGER
+  </refentrytitle>
+  <refmiscinfo>SQL - Language Statements</refmiscinfo>
+ </refmeta>
+ <refnamediv>
+  <refname>
+   ALTER TRIGGER
+  </refname>
+  <refpurpose>
+   change the definition of a trigger
+  </refpurpose>
+ </refnamediv>
+ <refsynopsisdiv>
+  <refsynopsisdivinfo>
+   <date>2002-04-19</date>
+  </refsynopsisdivinfo>
+  <synopsis>
+ALTER TRIGGER <replaceable class="PARAMETER">trigger</replaceable> ON <replaceable class="PARAMETER">table</replaceable>
+    RENAME TO <replaceable class="PARAMETER">newname</replaceable>
+  </synopsis>
+
+  <refsect2 id="R2-SQL-ALTERTRIGGER-1">
+   <refsect2info>
+    <date>2002-04-19</date>
+   </refsect2info>
+   <title>
+    Inputs
+   </title>
+   <para>
+    <variablelist>
+
+     <varlistentry>
+      <term><replaceable class="PARAMETER"> trigger </replaceable></term>
+      <listitem>
+       <para>
+	The name of an existing trigger to alter.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><replaceable class="PARAMETER"> table </replaceable></term>
+      <listitem>
+       <para>
+	The name of the table on which this trigger acts.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><replaceable class="PARAMETER"> newname </replaceable></term>
+      <listitem>
+       <para>
+	New name for the existing trigger.
+       </para>
+      </listitem>
+     </varlistentry>
+
+    </variablelist>
+   </para>
+  </refsect2>
+
+  <refsect2 id="R2-SQL-ALTERTRIGGER-2">
+   <refsect2info>
+    <date>2002-04-19</date>
+   </refsect2info>
+   <title>
+    Outputs
+   </title>
+   <para>
+
+    <variablelist>
+     <varlistentry>
+      <term><computeroutput>ALTER</computeroutput></term>
+      <listitem>
+       <para>
+	Message returned from trigger renaming.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><computeroutput>ERROR</computeroutput></term>
+      <listitem>
+       <para>
+	Message returned if trigger is not available, or new name is a duplicate of another existing trigger on the table.
+       </para>
+      </listitem>
+     </varlistentry>
+    </variablelist>
+   </para>
+  </refsect2>
+ </refsynopsisdiv>
+
+ <refsect1 id="R1-SQL-ALTERTRIGGER-1">
+  <refsect1info>
+   <date>2002-04-19</date>
+  </refsect1info>
+  <title>
+   Description
+  </title>
+  <para>
+   <command>ALTER TRIGGER</command> changes the definition of an existing trigger.
+   The <literal>RENAME</literal> clause causes the name of a trigger on the given table
+   to change without otherwise changing the trigger definition.
+  </para>
+
+  <para>
+   You must own the table on which the trigger acts in order to change its properties.
+  </para>
+
+  <refsect2 id="R2-SQL-ALTERTRIGGER-3">
+   <refsect2info>
+    <date>2002-04-19</date>
+   </refsect2info>
+   <title>
+    Notes
+   </title>
+   <para>
+    Refer to <command>CREATE TRIGGER</command> for a further description
+    of valid arguments.
+   </para>
+  </refsect2>
+ </refsect1>
+
+ <refsect1 id="R1-SQL-ALTERTRIGGER-2">
+  <title>
+   Usage
+  </title>
+  <para>
+   To rename an existing trigger:
+   <programlisting>
+ALTER TRIGGER emp_stamp ON emp RENAME TO emp_track_chgs;
+   </programlisting>
+  </para>
+ </refsect1>
+
+ <refsect1 id="R1-SQL-ALTERTRIGGER-3">
+  <title>
+   Compatibility
+  </title>
+
+  <refsect2 id="R2-SQL-ALTERTRIGGER-4">
+   <refsect2info>
+    <date>2002-04-19</date>
+   </refsect2info>
+   <title>SQL92</title>
+   <para>
+    The clause to rename triggers is a
+    <productname>PostgreSQL</productname> extension from SQL92.
+   </para>
+  </refsect2>
+ </refsect1>
+</refentry>
+
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+-->