JWColby
jwcolby at colbyconsulting.com
Mon Aug 28 10:59:51 CDT 2006
I do that when I am running into a speed issue. In this case I just wanted to do a "prefilter" to eliminate all records where dates are null before sending it on to a query that expects all dates to be not null. It LOOKS like it prefilters, but in fact it apparently does not. John W. Colby Colby Consulting www.ColbyConsulting.com -----Original Message----- From: accessd-bounces at databaseadvisors.com [mailto:accessd-bounces at databaseadvisors.com] On Behalf Of Michael R Mattys Sent: Monday, August 28, 2006 11:17 AM To: Access Developers discussion and problem solving Subject: Re: [AccessD] Did you know? Or more correctly - I never knew... ----- Original Message ----- From: "JWColby" <jwcolby at colbyconsulting.com> To: "'Access Developers discussion and problem solving'" <accessd at databaseadvisors.com> Sent: Monday, August 28, 2006 10:44 AM Subject: [AccessD] Did you know? Or more correctly - I never knew... -Snip- > It turns out that even though the base query pulls out only the > records with dates, it apparently hands ALL the records up to the > query built on top of the base query and since some of those records > have nulls in the dates, the appointment function complains about > nulls passed in to the date fields. -Snip- > So... why is it doing this, and is there a way to force the base query > to only pass up the filtered result set such that only valid dates are > pulled? -Snip- The fastest way to get the desired result set would be to append to a temp table. As to why ... there was a Deconstructing Querydefs article by Ken Getz a few years ago that might help to explain it. The link at http://www.developershandbook.com/downloads.htm is dead. I wonder if anyone saved the article? Michael R. Mattys MapPoint Developer www.mattysconsulting.com -- AccessD mailing list AccessD at databaseadvisors.com http://databaseadvisors.com/mailman/listinfo/accessd Website: http://www.databaseadvisors.com