On Thu, 15 Apr 2004, [ISO-8859-1] Sebastian Böck wrote: > is there a simple operator to determine whether the OLD.value and > NEW.value are different. The <> operator is not working on NULL's. Not as far as I know, although I think you can simplify the last part as (NEW.val IS NULL <> OLD.val IS NULL) > I need something like this: > NEW.val <> Old.val OR > NEW.val IS NULL AND OLD.val IS NOT NULL OR > NEW.val IS NOT NULL AND OLD.val IS NULL ---------------------------(end of broadcast)--------------------------- TIP 6: Have you searched our list archives? http://archives.postgresql.org