--由父项递归下级
with cte(id,parentid,text) as
(
--父项
select id,parentid,text from treeview where parentid = 450
union all
--递归结果集中的下级
select t.id,t.parentid,t.text from treeview as t
inner join cte as c
on t.parentid = c.id
)
select id,parentid,text from cte
---------------------
--由子级递归父项
with cte(id,parentid,text) as
(
--下级父项
select id,parentid,text from treeview where id = 450
union all
--递归结果集中的父项
select t.id,t.parentid,t.text from treeview as t
inner join cte as c
on t.id = c.parentid
)
select id,parentid,text from cte
原文：http://www.cnblogs.com/yf2011/p/5139248.html