If I get the point right, you want to use a computed column in the select query. In that case, you should use something like (sorry for possible syntax errors, I have no SQL available where I currently reside 🙂 ):
select * from
(
select SomeColumWithComputation as ComputedColumn
from SomeTable
) tmp
where ComputedColumn=bla
Cheers! Bert
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MCPD Web Developer, MCPD Windows Developer[/font]
Computers are made to solve problems you did not have in the days they didn't exist.