if (mysql_num_rows(queryMysql("SELECT * FROM doctor
                  WHERE username='$username' UNION SELECT * FROM patient
                  WHERE username='$username'")))
                $error = "That username already exists<br /><br />";
            else
              {
                queryMysql("INSERT INTO doctor (fname,lname,username,email,password,gender,age,specialty,doctorID) VALUES('$fname','$lname','$username','$email', '$password','$DoctorG','$DoctorAge','$specialty','$Doctor_ID')");
                die("<h4>Account created</h4>Please Log in.<br /><br />");
              }