PHP array or SQL problem

I've got a database with lname (lastname), fname (firstname), and nickname. What I want to do is search by either first name or last name. Either way, I display the nickname instead of the firstname if it exists. I have no problems on the last name, but when I sort by firstname, the people with nicknames that are very different come up at the place where their first name (not the displayed name) is. For example: Adam Smith Joe Schmoe Bill Somebody When Bill Somebody is really William Somebody in the database, his nickname is bill and that's what's displayed but he 'bill' shows up in 'williams' spot. Here is my SQL query: select * from employees order by fname; Should I create an array and sort it there or can I somehow query MySQL to sort by nickname only if it exists and then by fname? Dean