MS SQL 递归函数

 declare @ID varchar(10)
set @ID=9 --根节点
declare @i int --级数
declare @t table(ID varchar(10),ParentID varchar(10),Level int)
set @i = 1
insert into @t select @ID,0,0 --当前级，本级，如果不要的话可以注释掉或再加个参数来选择操作
insert into @t select ID,ParentID,@i from t_menuprivilege where ParentID = @ID
while @@rowcount<>0
begin
set @i = @i + 1
insert into @t
select
a.ID,a.ParentID,@i
from
t_menuprivilege a,@t b
where
a.ParentID=b.ID and b.Level = @i-1
end
select * from @t