title: MySQL query for page ancestor
body: <p>I have a MySQL table of pages with these fields (<code>id</code>, <code>parentID</code>, <code>name</code>, <code>content</code>).</p>
  
  <p>The page hierarchy is:</p>
  
  <pre>
   - About Us 
     - History 
       - 2000
       - 2001
  </pre>
  
  <p>If I'm on page "2001" how can I create a query to find that this page's top-level ancestor is "About Us"?</p>