thanks, but i think i done it. Not necessary a subquery, that was the problem. update b set areainicial=area(p.the_geom) from p where b.numerodist=p.numerodist and b.numerosecc=p.numerosecc; Galois -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.refractions.net/pipermail/postgis-users/attachments/20070410/771b188c/attachment.html