|Subject||Re: [firebird-support] Uniqueness among non-null values in nullable column?|
> On 24/04/12 09:29, Kjell Rilbe wrote:Yes. Sort of, I don't know the MSSQL internals.
>> 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?
Google offers a lot of discussions on that SQL-standard
compliant-breaking behaviour in SQL Server.
Thomas Steinmaurer (^TS^)
Firebird Technology Evangelist
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