not process role-specific variable settings.
       </para>

       <para>
        See <xref linkend="sql-set"/> and <xref
        linkend="runtime-config"/> for more information about allowed
        parameter names and values.
       </para>
      </listitem>
     </varlistentry>
    </variablelist>
 </refsect1>

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

  <para>
   Use <link linkend="sql-createrole"><command>CREATE ROLE</command></link>
   to add new roles, and <link linkend="sql-droprole"><command>DROP ROLE</command></link> to remove a role.
  </para>

  <para>
   <command>ALTER ROLE</command> cannot change a role's memberships.
   Use <link linkend="sql-grant"><command>GRANT</command></link> and
   <link linkend="sql-revoke"><command>REVOKE</command></link>
   to do that.
  </para>

  <para>
   Caution must be exercised when specifying an unencrypted password
   with this command.  The password will be transmitted to the server
   in cleartext, and it might also be logged in the client's command
   history or the server log.  <xref linkend="app-psql"/>
   contains a command
   <command>\password</command> that can be used to change a
   role's password without exposing the cleartext password.
  </para>

  <para>
   It is also possible to tie a
   session default to a specific database rather than to a role; see
   <xref linkend="sql-alterdatabase"/>.
   If there is a conflict, database-role-specific settings override role-specific
   ones, which in turn override database-specific ones.
  </para>
 </refsect1>

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

  <para>
   Change a role's password:

<programlisting>
ALTER ROLE davide WITH PASSWORD 'hu8jmn3';
</programlisting>
  </para>

  <para>
   Remove a role's password:

<programlisting>
ALTER ROLE davide WITH PASSWORD NULL;
</programlisting>
  </para>

  <para>
   Change a password expiration date, specifying that the password
   should expire at midday on 4th May 2015 using
   the time zone which is one hour ahead of <acronym>UTC</acronym>:
<programlisting>
ALTER ROLE chris VALID UNTIL 'May 4 12:00:00 2015 +1';
</programlisting>
  </para>

  <para>
   Make a password valid forever:
<programlisting>
ALTER ROLE fred VALID UNTIL 'infinity';
</programlisting>
  </para>

  <para>
   Give a role the ability to manage other roles and create new databases:

<programlisting>
ALTER ROLE miriam CREATEROLE CREATEDB;
</programlisting>
  </para>

  <para>
   Give a role a non-default setting of the
   <xref linkend="guc-maintenance-work-mem"/> parameter:

<programlisting>
ALTER ROLE worker_bee SET maintenance_work_mem = 100000;
</programlisting>
  </para>

  <para>
   Give a role a non-default, database-specific setting of the
   <xref linkend="guc-client-min-messages"/> parameter:

<programlisting>
ALTER ROLE fred IN DATABASE devel SET client_min_messages = DEBUG;
</programlisting></para>
 </refsect1>

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

  <para>
   The <command>ALTER ROLE</command> statement is a
   <productname>PostgreSQL</productname> extension.
  </para>
 </refsect1>

 <refsect1 id="sql-alterrole-see">
  <title>See Also</title>

  <simplelist type="inline">
   <member><xref linkend="sql-createrole"/></member>
   <member><xref linkend="sql-droprole"/></member>
   <member><xref linkend="sql-alterdatabase"/></member>
   <member><xref linkend="sql-set"/></member>
  </simplelist>
 </refsect1>
</refentry>