select .... where 1 = 2

I have an ace report which is used to print an invoice based on 2 different scenarios. In one case, I want to print all unprinted invoices. In another, I want to print a specific invoice. At the moment I'm trying to be clever and use the same report for both instances. So, what I ended up with is (grossly oversimplified): select field1, field2 from a,b where f3 = f4 and printed_date is null and "A" = $pass_param dummy_inv union select field-from-as-above where f3 = f4 and invoice num = $inv and "S" = $pass_param 312 My thought was: with the the report called as "sacego blah A #", I'd get the first select to work and "sacego blah S #" the second select would work, the joins creating a single set without temp tables. I've conducted an experiment using dbaccess with just the "A" case and, during a normal join, the select returns no records if $pass_param is "B", as it is supposed to do, but make it outer and it fails, giving records when I don't want any. Any thoughts? AIX 3.2.5 INFORMIX-SQL Version 4.11.UC2 INFORMIX-SQL Version 4.10.UG1 --Aaron Pelton | A person should live forever or die trying. aaron@silo-alcazar.com | S. Robinson #include<disclaimer.h> | Silo Music/Alcazar Records