<?php
// $node is the name of the node we want the path of
function get_path($node) {
   // look up the parent of this node
   $result = mysql_query('SELECT parent FROM tree '.
                          'WHERE title="'.$node.'";');
   $row = mysql_fetch_array($result);

   // save the path in this array
   $path = array();

   // only continue if this $node isn't the root node
   // (that's the node with no parent)
   if ($row['parent']!='') {
       // the last part of the path to $node, is the name
       // of the parent of $node
       $path[] = $row['parent'];

       // we should add the path to the parent of this node
       // to the path
       $path = array_merge(get_path($row['parent']), $path);
   }

   // return the path
   return $path;
}
?>