user datagrid

<?php
session_start();
if(!isset($_SESSION['valid']))
  header('Location: login.php');
else{
  include_once("config.php");
  $result=mysql_query("SELECT id,name,age,email FROM users ORDER BY id DESC");
  ?>
<html>
<title>Homepage</title>
<body>
  <a href='index.php'>Home</a> | <a href="add.html">Add New Data</a>
  <br/><br/>
  <table width='100%' border=0>
    <tr bgcolor='#CCCCCC'>
      <th>Name</th>
      <th>Age</th>
      <th>Email</th>
      <th>Update</th>
    </tr>
<?php
  while($res=mysql_fetch_assoc($result)){
    echo "
    <tr>
      <td>".$res['name']."</td>
      <td>".$res['age']."</td>
      <td>".$res['email']."</td>
      <td><a href='edit.php?id={$res['id']}'>Edit</a> | <a href='delete.php?id={$res['id']}'>Delete</a></td>
    </tr>";
  }
}
?>
  </table>
</body>
</html>