doc-dblink_error_message-01.patch

diff --git a/doc/src/sgml/dblink.sgml b/doc/src/sgml/dblink.sgml
index 87e14ea..97dc3b8 100644
*** a/doc/src/sgml/dblink.sgml
--- b/doc/src/sgml/dblink.sgml
*************** dblink_error_message(text connname) retu
*** 1165,1175 ****
     <title>Return Value</title>
  
     <para>
!     Returns last error message, or an empty string if there has been
      no error in this connection.
     </para>
    </refsect1>
  
    <refsect1>
     <title>Examples</title>
  
--- 1165,1189 ----
     <title>Return Value</title>
  
     <para>
!     Returns last error message, or <literal>OK</literal> if there has been
      no error in this connection.
     </para>
    </refsect1>
  
+   <refsect1>
+    <title>Notes</title>
+ 
+    <para>
+     When asynchronous queries are initiated by
+     <function>dblink_send_query</function>, the error message associated with
+     the connection might not get updated until the server's response message
+     is consumed. This typically means that <function>dblink_is_busy</function>
+     or <function>dblink_get_result</function> should be called prior to
+     <function>dblink_error_message</function>, so that any error generated by
+     the asynchronous query will be visible.
+    </para>
+   </refsect1>
+ 
    <refsect1>
     <title>Examples</title>