T-SQL User-Defined Functions: the good, the bad, and the ugly (part 2)

Posted by Hugo Kornelis on SQL Blog See other posts from SQL Blog or by Hugo Kornelis
Published on Sat, 26 May 2012 14:56:00 GMT Indexed on 2012/05/30 16:54 UTC
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In a previous blog post , I demonstrated just how much you can hurt your performance by encapsulating expressions and computations in a user-defined function (UDF). I focused on scalar functions that didn’t include any data access. In this post, I will complete the discussion on scalar UDFs by covering the effect of data access in a scalar UDF. Note that, like the previous post, this all applies to T-SQL user-defined functions only. SQL Server also supports CLR user-defined functions (written in...(read more)

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