custom sql query

Hello, We have a database that contains usernames and password that we want to auth from using a web app we have. I have tried all kinds of config's in the sql.conf file and still get fails I have turned on sqltrace and here is the error we currently get, its not much... rlm_sql (sql): Reserving sql socket id: 2 rlm_sql (sql): SQL query error; rejecting user rlm_sql (sql): Released sql socket id: 2 Right now to retrieve username and password...(sql script) we use this from sql query select Username, Password from Contact where length(Username) > 0; How do I slap that into sql.conf to make it work for simply just username/password auth? Any help would be appreciated.