<?php
// Create a connection to the logindb database and to MySQL.
// Set the encoding and the access details as constants:
DEFINE ('DB_USER', 'johny');
DEFINE ('DB_PASSWORD', 'some_pass');
DEFINE ('DB_HOST', 'localhost');
DEFINE ('DB_NAME', 'biblioteczka');
// Make the connection:
$dbcon = @mysqli_connect(DB_HOST,DB_USER,DB_PASSWORD,DB_NAME)
OR die ('Could not connect to MySQL: ' . mysqli_connect_error() );

$ID = $_POST['user'];
$PASSWORD = $_POST['pass'];
// Set the encoding...
mysqli_set_charset($dbcon, 'utf8');
function SignIn(){
    session_start();
    if(!empty($_POST['user'])){
        $query = mysql_query("SELECT * FROM userName where user ='$_POST[user]' and pass = '$_POST[pass]'"
                or die(mysql_error));
        $row = mysql_fetch_array($query) or die(mysql_error());
        if(!empty($row['userName']) AND !empty($row['pass'])){
            $_SESSION['userName'] = $row['pass'];
            echo "SUCCESSFULLY LOGIN TO USER PROFILE PAGE...";
        } else {
            echo "SORRY... YOU ENTERD WRONG ID AND PASSWORD... PLEASE RETRY...";
        }

    }
}
if(isset($_POST['submit']))
{
    SignIn();
}
?>