>>He is not. I already gave you links that this is a debatable topic and many great authorities in database design share Kevin's approach to not allow NULLs in the Foreign Keys but rather use the predefined value for 'Unknown' and have this as an entry in the primary table.
>
>Then I disagree with all of them. Null is the predefined value for Unknown. Inventing a new one is asking for trouble.
>
>And now I will shut up about it.
>
>It's nice to see you and Kevin on the same side, BTW ;-)

Why not? :) Also, I think Kevin knows what he is talking about when he talks about SQL Server :) And .NET topics.