Segíts

<?php
 $con = mysqli_connect("localhost","TITOK","TITOK","classmch_wp");
$username = $_GET['username'];

$password = $_GET['password'];

$sel_user = "select * from players where username=’$username’ AND password=’$password'";

$run_user = mysqli_query($con, $sel_user);

$check_user = mysqli_num_rows($run_user);
 if($check_user<0)
 {
  echo "1";
 }
 else
 {
	if(empty($uname) or empty($upass)) {
		echo "Hiányzó adatok!";
	 }else {
		echo "2";
	 }
 }
?>