MDO select query: how to control sort order using parameter

Hi experts, is there a way of controling the sort order of an MDO select query using some parameter?

I was thinking about using some statement like CASE [Param.1] WHEN 'abc' THEN [ORDER_NO]...END in sort section of the query but it is not working.

Of course I colud go for various select queries...but I am wondering if it can be done using only one?

Any ideas?

Thanks for any help