Asger Blond
ab-mi at post3.tele.dk
Mon May 14 06:44:22 CDT 2012
13th February 2010, I wrote the following warning: Hi group, Just downloaded the Access 2010 Beta and observed that a new data type for fields was added: Calculated. Knowing that this kind of denormalized field has been around in SQL Server for some time I thought it would be the same in A2K10. Well: It's not! In SQL Server a calculated field is not persisted, it's just a convenient way to pre-announce a calculation which will be used on the fly when querying the table. You can in fact persist the calculated values in SQL Server, but only if you create an index on the field - otherwise it's of course not persisted. So I was astonished in A2K10 that I didn't have a choice whether to index this kind of field. I then created a test db containing a table with two number-fields and one million records. Size of the db: 33 GB. To check I copied the db to a new db and added a calculated field to the table (trivial calculation: Field1 * Field2). And guess what? The size of the new db was double up+: 72 GB. So please: stick to your old practice creating calculations only in queries, and don't ever use the new Calculated field type in Access 2010! /Asger -----Oprindelig meddelelse----- Fra: accessd-bounces at databaseadvisors.com [mailto:accessd-bounces at databaseadvisors.com] På vegne af Mark Simms Sendt: 14. maj 2012 10:46 Til: 'Access Developers discussion and problem solving' Emne: Re: [AccessD] AC2010-a pioneer with more arrows in the back... Of course Charlotte, doing it in a query was the old-school way. I tried to use a new feature and got burnt...that's all. The feature does work well, but is very touchy when it comes to any changes. -- AccessD mailing list AccessD at databaseadvisors.com http://databaseadvisors.com/mailman/listinfo/accessd Website: http://www.databaseadvisors.com