MySQL：对GROUP_CONCAT值进行排序

简而言之：有什么方法可以对GROUP_CONCAT语句中的值进行排序吗？

查询：

GROUP_CONCAT((SELECT GROUP_CONCAT(parent.name SEPARATOR " » ") 
FROM test_competence AS node, test_competence AS parent 
WHERE node.lft BETWEEN parent.lft AND parent.rgt 
  AND node.id = l.competence 
  AND parent.id != 1 
ORDER BY parent.lft) SEPARATOR "<br />\n") AS competences

我得到这一行：

工艺品»细木工

行政管理»组织

我想要这样：

行政管理»组织

工艺品»细木工

当然，请参见http://dev.mysql.com/doc/refman/...tions.html#function_group-concat：

SELECT student_name,
  GROUP_CONCAT(DISTINCT test_score ORDER BY test_score DESC SEPARATOR ' ')
  FROM student
  GROUP BY student_name;

您是要订购吗？

SELECT _key,            
COUNT(*) as cnt,            
GROUP_CONCAT(_value ORDER BY _value SEPARATOR ', ') as value_list      
FROM group_concat_test      
GROUP BY _key      
ORDER BY _key;