diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
new file mode 100644
index 86ff4e5..f638c6d
*** a/doc/src/sgml/func.sgml
--- b/doc/src/sgml/func.sgml
*************** SELECT current_setting('datestyle');
*** 18722,18728 ****
      If there is no setting named <parameter>setting_name</parameter>,
      <function>current_setting</function> throws an error
      unless <parameter>missing_ok</parameter> is supplied and is
!     <literal>true</literal>.
     </para>
  
     <para>
--- 18722,18729 ----
      If there is no setting named <parameter>setting_name</parameter>,
      <function>current_setting</function> throws an error
      unless <parameter>missing_ok</parameter> is supplied and is
!     <literal>true</literal>, in which case a missing parameter returns
!     NULL.
     </para>
  
     <para>