ช่วยดูหน่อยครับต้องการ ทำ login แบบ แบ่งระดับ 2 ระดับ

<?
session_start();    
$_SESSION["username_log"] = $_POST["username_log"];
$_SESSION["fname_log"] = $_POST["fname_log"];
$hostname = "localhost"; 
$user = "root"; 
$password = "1234";    
$dbname = "stu"; 
$tblname = "stu"; 

mysql_connect($hostname, $user, $password) or die; 

mysql_select_db($dbname) or die;

$sql = "select * from $tblname where stu_username='$username_log' and stu_password='$password_log'";       
$dbquery = mysql_db_query($dbname, $sql);


$num_rows = mysql_num_rows($dbquery);
if($num_rows==1){   
header("location: data/member.php"); 
}else {

header("location: data/falselogin.php");
}
?>