Re: Null variables

NULL is special. NULL doesn't equal anything because it is by definition undefined. So undefined != undefined (not true). Where ever you use NULL you cannot use an equality or inequality statement. This leads to some interesting things: NULL = NULL (false) NULL != NULL (false) NULL = foo (false) NULL != foo (false) There is therefore a special test for NULL which does not involve an equality statement - 'IS NULL'. IF a IS NULL THEN .... try to remember to use this power only for good. cheers j. "Florin Micle" <florinmicle@gsc-mbh.de> on 08/12/98 12:44:22 PM Please respond to "Florin Micle" <florinmicle@gsc-mbh.de> To: informix-list@iiug.org cc: (bcc: Jack Parker/Boston50/Epsilon) Subject: Null variables Hi all, Does anyone know how can I see if a passed variable into a stored procedure in Informix (dbaccess) has null value? I can't compare it with null because I get a syntax error (null - undeclared variable) if I pass null value into another variable the evaluation of null = null returns false! I wish it returned true... Can anyone give me a solution for this? Thanks, Florin.