<?php
// establishing the mysqli connection
$con = mysqli_connect("localhost","root","","USERS");

if(mysqli_connect_error())
{
echo "My SQLi Connection was not established:".mysqli_connect();
}
//checking the user
if(isset($_POST['login'])){
$Password = mysqli_real_escape_string($con,$_POST['Password']);
$sel_userName= "sel*from users where userName='userName AND Password='$Password'";
$run_userName = mysqli_query($con,$sel_userName);

$check_userName = mysqli_num_rows($run_userName);

if(check_userName>o){
$_SESSION['userName']=$userName
echo "<script>window.open(‘NEW.php’,’_self’)</script>";
}
else{
echo"<script>alert('Username or password is incorrect,try again!’)</script>';
}
}
?>