title: Calculate age based on date of birth
body: <p>I have a table of users in sql and they each have birth dates. I want to convert their date of birth to their age (years only), e.g. date: <code>15.03.1999</code> age: 14 and <code>15.03.2014</code> will change to age: <code>15</code></p>
  
  <p>Here I want to show the date of the user:</p>
  
  <pre><code>if(isset($_GET['id']))
  {
      $id = intval($_GET['id']);
      $dnn = mysql_fetch_array($dn);
      $dn = mysql_query('select username, email, skype, avatar, ' .
          'date, signup_date, gender from users where id="'.$id.'"');
      $dnn = mysql_fetch_array($dn);
      echo "{$dnn['date']}";
  }
  </code></pre>