<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1
/jquery.min.js"></script>

<script type="text/javascript">

 $(document).bind('keypress', function(e) {
    if (e.keyCode == 116){
      validNavigation = true;
    }
  });

  // Attach the event click for all links in the page
  $("a").bind("click", function() {
    validNavigation = true;
  });

  // Attach the event submit for all forms in the page
  $("form").bind("submit", function() {
    validNavigation = true;
  });

  // Attach the event click for all inputs in the page
  $("input[type=submit]").bind("click", function() {
    validNavigation = true;
  });

 window.addEventListener("beforeunload", function (e) {
 if (!validNavigation) {
 $.ajax({
url: 'logout.php',
type: 'POST',
async: false,
timeout: 4000
});
}
})
</script>

<?php
$username = "root";
$password = "";
$hostname = "localhost";

$dbhandle = mysql_connect($hostname, $username, $password)
 or die("Unable to connect to MySQL");
echo "Connected to MySQL<br>";


$selected = mysql_select_db("examples",$dbhandle)
  or die("Could not select examples");

$result =  mysql_query("DELETE FROM cars WHERE id='1'");
mysql_close($dbhandle);
?>