I just tried it in V13 SQL Assistant and I don't get the NULL. When Field is NULL I'm getting 0. But your format statement will suppress the zero so all you see is spaces. Try ZZZ,ZZZ,Z9 instead and see if that works. But also if you are using an earlier version of SQL Assistant it is probably ignoring your format statements altogether. In that case you can cast the final formatted result to a character string.