RE: [CFCDev] GUIDs as Primary/Foreign Keys

[Dawson, Michael]

As long as you don't mix the two types of GUIDs in the same column, it's not an issue.  Even if you do, it won't make a difference unless you specifically use "uniqueidentifier" as the data type.  Otherwise, use char or varchar.   I will say that I don't know if uniqueidentifier has better performance than a char that holds the same data.   Yes, the joins will be slower, but it will all depend on your implementation, number of records and indices.  I don't think you will notice a difference until you get into the hundreds of thousands of records, if you have capable hardware.   MAD From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Schreck, Tom Sent: Wednesday, December 08, 2004 8:27 AM To: [EMAIL PROTECTED] Subject: RE: [CFCDev] GUIDs as Primary/Foreign Keys I had not thought of the ability to generate them before the db insert.  That’s interesting.  I do know that a CF GUID (createUUID()) is not the same as a SQL Server generated GUID (newID()).   What are your thoughts on performance of joins in select statements when you join on a GUID?  It seems the database performance will decrease when querying using joins on GUIDs.   Thanks   Tom Schreck 972-361-9943