Sort Joomla items by parent

gistfile1.php

<?php
$query
->select($this->db->quoteName(array(
	'title',
	'id',
	'parent_id')))
->select($this->db->quoteName('metadesc', 'description'))
->from($this->db->quoteName('#__categories'))
->order($this->db->quoteName('parent_id') . ' ASC')
->order($this->db->quoteName('ordering') . ' ASC');


$children = array();
if ($items)
{
	foreach ($items as $item)
	{
		$list   = @$children[$item->parent] ? $children[$item->parent] : array();
		array_push($list, $item);
		$children[$item->parent] = $list;
	}
}