You could find this article useful
http://www.sqlservercentral.com/articles/T-SQL/88244/
SELECT AttribID
FROM MyTable
WHERE FormatID IN (12,15)
GROUP BY AttribID
HAVING COUNT(DISTINCT FormatID ) = 2
EXCEPT
SELECT AttribID
FROM MyTable
WHERE FormatID <> 27
Luis C.
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Are you seriously taking the advice and code from someone from the internet without testing it? Do you at least understand it? Or can it easily kill your server?
How to post data/code on a forum to get the best help: Option 1 / Option 2