On 24/04/12 09:29, Kjell Rilbe wrote: > SQL Server UNIQUE allows only a single null.
Interesting. That's one for the "Learn something new every day" department! It does tend to imply that SQL Server is treating NULL (a lack of a value) as a value in this case? Cheers, Norm. -- Norman Dunbar Dunbar IT Consultants Ltd Registered address: Thorpe House 61 Richardshaw Lane Pudsey West Yorkshire United Kingdom LS28 7EL Company Number: 05132767
