On 15 Apr 2002 at 14:20, Nick Fankhauser wrote: > As a general rule, a primary key (or any relationship key) should not > contain a value that means something beyond its use in relating entities. > The problem is that if a field describes an object, the day may come when > you want to change the description, but you *never* want to change the > field that identifies the record and relates it to other records.
FWIW, I would recommend not using business values as a primary key (and by extension, as a foreign key). Business values are just that: business values. Sure, put unique constraints on business values if you want. Just don't make them a primary key or a foreign key. -- Dan Langille The FreeBSD Diary - http://freebsddiary.org/ - practical examples ---------------------------(end of broadcast)--------------------------- TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED]