UPDATE using sub selects

Hi, <br /><br />I have coded up a patch which solves the following TODO. I will submit a patch for this soon:<br /><br
/><ul><li>UPDATE<ul><li>Allow UPDATE tab SET ROW (col, ...) = (SELECT...) <p><a
href="http://archives.postgresql.org/pgsql-hackers/2006-07/msg01306.php">http://archives.postgresql.org/pgsql-hackers/2006-07/msg01306.php</a></ul></ul><br
/>Thequestion is that since this enhances the UPDATE syntax, what changes and where all they need to be made with
respectto the documentation?<br clear="all" /><br />Regards,<br />Nikhils<br />-- <br />EnterpriseDB               <a
href="http://www.enterprisedb.com">http://www.enterprisedb.com</a>