> 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?
Yes. Sort of, I don't know the MSSQL internals. Google offers a lot of discussions on that SQL-standard compliant-breaking behaviour in SQL Server. > Cheers, > Norm. > -- With regards, Thomas Steinmaurer (^TS^) Firebird Technology Evangelist http://www.upscene.com/ Do you care about the future of Firebird? Join the Firebird Foundation: http://www.firebirdsql.org/en/firebird-foundation/
