ต้องการนำค่า password จาก table มาเทียบกับค่า password ที่ได้จาก application ครับ

$password=trim($_POST['old_password']);

$objConnect = mysql_connect("localhost","root","password3") or die("Error Connect to Database");
$objDB = mysql_select_db("agrodb_v3");
$str = "SELECT oldpassword  from change_password_email where oldpassword LIKE '$password'";
$query = mysql_query($str);
$num = mysql_num_rows($query);

if($num>0){
echo "พาสถูกต้อง";
}else{
echo "พาสไม่ถูกต้อง";
}

if(!oldpassword){
echo "pass wrong";
}else{
echo "pass correct";
}

$id=trim($_POST['user_id']);
$password=trim($_POST['old_password']);

$objConnect = mysql_connect("localhost","root","password3") or die("Error Connect to Database");
$objDB = mysql_select_db("agrodb_v3");
$str = "SELECT oldpassword  from change_password_email where user='$id'  AND oldpassword LIKE '$password'";
$query = mysql_query($str);
$num = mysql_num_rows($query);

if($num>0){
echo "พาสถูกต้อง";
}else{
echo "พาสไม่ถูกต้อง";
}
$strSQL = "UPDATE change_password_email SET date=now(),time=now() ,  oldpassword = '$newpassword' WHERE user = '$id' ";