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

   <varlistentry>
    <term><replaceable class="parameter">argmode</replaceable></term>
    <listitem>
     <para>
      The mode of a function, procedure, or aggregate
      argument: <literal>IN</literal>, <literal>OUT</literal>,
      <literal>INOUT</literal>, or <literal>VARIADIC</literal>.
      If omitted, the default is <literal>IN</literal>.
      Note that <command>COMMENT</command> does not actually pay
      any attention to <literal>OUT</literal> arguments, since only the input
      arguments are needed to determine the function's identity.
      So it is sufficient to list the <literal>IN</literal>, <literal>INOUT</literal>,
      and <literal>VARIADIC</literal> arguments.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">argname</replaceable></term>
    <listitem>
     <para>
      The name of a function, procedure, or aggregate argument.
      Note that <command>COMMENT</command> does not actually pay
      any attention to argument names, since only the argument data
      types are needed to determine the function's identity.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">argtype</replaceable></term>
    <listitem>
     <para>
      The data type of a function, procedure, or aggregate argument.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">large_object_oid</replaceable></term>
    <listitem>
     <para>
      The OID of the large object.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">left_type</replaceable></term>
    <term><replaceable class="parameter">right_type</replaceable></term>
    <listitem>
     <para>
      The data type(s) of the operator's arguments (optionally
      schema-qualified).  Write <literal>NONE</literal> for the missing argument
      of a prefix operator.
     </para>
    </listitem>
   </varlistentry>

    <varlistentry>
     <term><literal>PROCEDURAL</literal></term>
     <listitem>
      <para>
       This is a noise word.
      </para>
     </listitem>
    </varlistentry>

    <varlistentry>
     <term><replaceable>type_name</replaceable></term>

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

    <varlistentry>
     <term><replaceable>lang_name</replaceable></term>

     <listitem>
      <para>
       The name of the language of the transform.
      </para>
     </listitem>
    </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">string_literal</replaceable></term>
    <listitem>
     <para>
      The new comment contents, written as a string literal.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><literal>NULL</literal></term>
    <listitem>
     <para>
      Write <literal>NULL</literal> to drop the comment.
     </para>
    </listitem>
   </varlistentry>

  </variablelist>
 </refsect1>

 <refsect1>
  <title>Notes</title>

  <para>
   There is presently no security mechanism for viewing comments: any user
   connected to a database can see all the comments for objects in
   that database.  For shared objects such as
   databases, roles, and tablespaces, comments are stored globally so any
   user connected to any database in the cluster can see all the comments
   for shared objects.  Therefore, don't put security-critical