Gail, this isn't a catch-all query. According your article, a catch-all query is one "where the user may enter any one (or more) of a number of optional parameters". Here, the clearly stated requirement is different: "I allways submit all 4 input values". Those four values must, therefore, always be tested for - I don't see any other way to fulfil the requirement than the basic structure the OP ended up with in his final post.

John