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$PostgreSQL: pgsql/doc/src/sgml/ref/drop_sequence.sgml,v 1.28 2008/11/14 10:22:46 petere Exp $
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<refentry id="SQL-DROPSEQUENCE">
 <refmeta>
  <refentrytitle id="SQL-DROPSEQUENCE-TITLE">DROP SEQUENCE</refentrytitle>
  <manvolnum>7</manvolnum>
  <refmiscinfo>SQL - Language Statements</refmiscinfo>
 </refmeta>

 <refnamediv>
  <refname>DROP SEQUENCE</refname>
  <refpurpose>remove a sequence</refpurpose>
 </refnamediv>

 <indexterm zone="sql-dropsequence">
  <primary>DROP SEQUENCE</primary>
 </indexterm>

 <refsynopsisdiv>
<synopsis>
DROP SEQUENCE [ IF EXISTS ] <replaceable class="PARAMETER">name</replaceable> [, ...] [ CASCADE | RESTRICT ]
</synopsis>
 </refsynopsisdiv>

 <refsect1>
  <title>Description</title>

  <para>
   <command>DROP SEQUENCE</command> removes sequence number
   generators. A sequence can only be dropped by its owner or a superuser.
  </para>
 </refsect1>
  
 <refsect1>
  <title>Parameters</title>

  <variablelist>
   <varlistentry>
    <term><literal>IF EXISTS</literal></term>
    <listitem>
     <para>
      Do not throw an error if the sequence does not exist. A notice is issued 
      in this case.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="PARAMETER">name</replaceable></term>
    <listitem>
     <para>
      The name (optionally schema-qualified) of a sequence.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><literal>CASCADE</literal></term>
    <listitem>
     <para>
      Automatically drop objects that depend on the sequence.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><literal>RESTRICT</literal></term>
    <listitem>
     <para>
      Refuse to drop the sequence if any objects depend on it.  This
      is the default.
     </para>
    </listitem>
   </varlistentry>
  </variablelist>
 </refsect1>

 <refsect1>
  <title>Examples</title>

  <para>
   To remove the sequence <literal>serial</literal>:

<programlisting>
DROP SEQUENCE serial;
</programlisting>
  </para>
 </refsect1>
 
 <refsect1>
  <title>Compatibility</title>

  <para>
   <command>DROP SEQUENCE</command> conforms to the <acronym>SQL</acronym>
   standard, except that the standard only allows one
   sequence to be dropped per command, and apart from the 
   <literal>IF EXISTS</> option, which is a <productname>PostgreSQL</> 
   extension. 
  </para>
 </refsect1>

 <refsect1>
  <title>See Also</title>

  <simplelist type="inline">
   <member><xref linkend="sql-createsequence" endterm="sql-createsequence-title"></member>
   <member><xref linkend="sql-altersequence" endterm="sql-altersequence-title"></member>
  </simplelist>
 </refsect1>

</refentry>
