The CASE function in SQL Server is an analog of IIF() function in VFP. It would affect performance the same way as any other T-SQL function.

SELECT < field list >, 
        SUM( CAST WHEN InvType='01' THEN Qty * UnitPrice ELSE 0 END) AS TotDollars...

>Question...
>
>I'm porting some VFP queries into SQL server, and have a question about embedding IIF() functions...
>
>I have a VFP query where I'm summing certain fields based on an Invoice type. In VFP, I do the following
>
>SELECT , SUM(IIF(InvType='01',Qty * UnitPrice,0)) AS TotDollars...
>
>What is the best way to do this in Transact-SQL? The only thing I've come across that would seem to work is a SELECT CASE statement in the query, though my question is how much this would affect performance when working on a large file.
>
>Thanks,
>Kevin

--sb--