JFYI There is little difference between passing the user/pass on the DBI connect call and putting it in the connection string IF the connection string contains DSN= or DRIVER=. What DBD::ODBC does is look for a DRIVER= or DSN= and if they are missing it calls SQLConnect first (for backwards compatibility) with the connection string, username and password. If SQLConnect fails or connection string contained DRIVER/DSN it appends the username/password passed in DBI->connect call to the connection string (unless the connection string already contains UID/PWD) and passes the resulting string to SQLDriverConnect.