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<refentry id="SQL-DROPCAST">
 <refmeta>
  <refentrytitle id="SQL-DROPCAST-TITLE">DROP CAST</refentrytitle>
  <refmiscinfo>SQL - Language Statements</refmiscinfo>
 </refmeta>

 <refnamediv>
  <refname>DROP CAST</refname>
  <refpurpose>remove a user-defined cast</refpurpose>
 </refnamediv>

 <refsynopsisdiv>
<synopsis>
DROP CAST (<replaceable>sourcetype</replaceable> AS <replaceable>targettype</replaceable>)
    [ CASCADE | RESTRICT ]
</synopsis>
 </refsynopsisdiv>
  
 <refsect1 id="sql-dropcast-description">
  <title>Description</title>

  <para>
   <command>DROP CAST</command> removes a previously defined cast.
  </para>

  <para>
   To be able to drop a cast, you must own the underlying function.
   To be able to drop a binary compatible cast, you must own both the
   source and the target data type.  These are the same privileges
   that are required to create a cast.
  </para>

   <variablelist>
    <title>Parameters</title>

    <varlistentry>
     <term><replaceable>sourcetype</replaceable></term>

     <listitem>
      <para>
       The name of the source data type of the cast.
      </para>
     </listitem>
    </varlistentry>

    <varlistentry>
     <term><replaceable>targettype</replaceable></term>

     <listitem>
      <para>
       The name of the target data type of the cast.
      </para>
     </listitem>
    </varlistentry>

    <varlistentry>
     <term><literal>CASCADE</literal></term>
     <term><literal>RESTRICT</literal></term>

     <listitem>
      <para>
       These key words do not have any effect, since there are no
       dependencies on casts.
      </para>
     </listitem>
    </varlistentry>
   </variablelist>

 </refsect1>

 <refsect1 id="sql-dropcast-notes">
  <title>Notes</title>

  <para>
   Use <command>CREATE CAST</command> to create user-defined casts.
  </para>

  <para>
   The privileges required to drop a cast may be changed in a future
   release.
  </para>
 </refsect1>


 <refsect1 id="sql-dropcast-examples">
  <title>Examples</title>

  <para>
   To drop the cast from type <type>text</type> to type <type>int</type>:
<programlisting>
DROP CAST (text AS int4);
</programlisting>
  </para>
 </refsect1>

 
 <refsect1 id="sql-dropcast-compat">
  <title>Compatibility</title>

  <para>
   The <command>DROP CAST</command> command conforms to SQL99.
  </para>
 </refsect1>


 <refsect1 id="sql-dropcast-seealso">
  <title>See Also</title>

  <para>
   <xref linkend="sql-createcast" endterm="sql-createcast-title">
  </para>
 </refsect1>

</refentry>

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