在SqlServer中通过SQL语句实现树状查询

CREATE PROCEDURE [dbo].[GetTree]
@Id int
AS
BEGIN
with cte as
(
select Id,Pid,Name,0 as lvl from Entity
where Id = @Id
union all
select e.Id,e.Pid,e.Name,lvl+1 from cte c inner join Entity e
on c.Id = e.Pid
)
select * from cte
END