Add documention for ecpg -209 error.

doc/src/sgml/ecpg.sgml

@@ -1,5 +1,5 @@
 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/ecpg.sgml,v 1.23 2001/09/13 15:55:22 petere Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/ecpg.sgml,v 1.24 2001/10/11 20:25:42 momjian Exp $
 -->
 
  <chapter id="ecpg">
@@ -331,6 +331,16 @@ struct sqlca
        </listitem>
       </varlistentry>
 
+      <varlistentry>
+       <term><computeroutput>-209, NULL value without indicator in line %d.</computeroutput></term>
+       <listitem>
+	<para>
+	 <productname>Postgres</productname> returned <symbol>ECPG_MISSING_INDICATOR</symbol>
+	 because a NULL was returned and no NULL indicator variable was supplied.
+	</para>
+       </listitem>
+      </varlistentry>
+
       <varlistentry>
        <term><computeroutput>-220, No such connection %s in line %d.</computeroutput></term>
        <listitem>