--2005 cte

;with cte as
(
    select fid,fparentid from tb where fid = 3  --查询节点
    union all
    select a.fid,a.fparentid
    from tb a join tb b on a.fparentid = b.id
    where a.id is not null
)

select * from cte

------解决方案--------------------

SQL code
给你个 函数
CREATE FUNCTION [dbo].[fn_getsubtree](@empid AS INT) 
    RETURNS @TREE TABLE
(
    empid   INT NOT NULL
    ,empname VARCHAR(25) NOT NULL
    ,mgrid   INT NULL
    ,lvl     INT NOT NULL
)
AS
BEGIN
  WITH Employees_Subtree(empid, empname, mgrid, lvl)
  AS
  ( 
    SELECT empid, empname, mgrid, 0
    FROM Employees
    WHERE empid = @empid

    UNION all
    SELECT e.empid, e.empname, e.mgrid, es.lvl+1
    FROM Employees AS e
      JOIN Employees_Subtree AS es
        ON e.mgrid = es.empid
  )
  INSERT INTO @TREE
    SELECT * FROM Employees_Subtree;

  RETURN
END

------解决方案--------------------

递归查询

------解决方案--------------------

SQL code

-->Title:Generating test data
-->Author:wufeng4552
-->Date :2009-09-30 08:52:38
set nocount on
if object_id('tb','U')is not null drop table tb
go
create table tb(ID int, ParentID int)
insert into tb select 1,0  
insert into tb select 2,1  
insert into tb select 3,1  
insert into tb select 4,2  
insert into tb select 5,3  
insert into tb select 6,5  
insert into tb select 7,6
-->Title:查找指定節點下的子結點
if object_id('Uf_GetChildID')is not null drop function Uf_GetChildID
go
create function Uf_GetChildID(@ParentID int)
returns @t table(ID int)
as
begin
   insert @t select ID from tb where ParentID=@ParentID
   while @@rowcount<>0
   begin
      insert @t select a.ID from tb a inner join @t b
      on a.ParentID=b.id and 
      not exists(select 1 from @t where id=a.id)
   end 
return
end
go
select * from dbo.Uf_GetChildID(5)
/*
ID
-----------
6
7
*/
-->Title:查找指定節點的所有父結點
if object_id('Uf_GetParentID')is not null drop function Uf_GetParentID
go
create function Uf_GetParentID(@ID int)
returns @t table(ParentID int)
as
begin
   insert @t select ParentID from tb where ID=@ID
   while @@rowcount!=0
   begin
     insert @t select a.ParentID from tb a inner join @t b
       on a.id=b.ParentID and 
       not exists(select 1 from @t where ParentID=a.ParentID)
   end
  return
end
go
select * from dbo.Uf_GetParentID(2)
/*
ParentID
-----------
1
0
*/


USE tempdb
GO

-- 建立演示环境
CREATE TABLE Dept(
 id int PRIMARY KEY, 
 parent_id int,
 name nvarchar(20))
INSERT Dept
SELECT 0, 0, N'<全部>' UNION ALL
SELECT 1, 0, N'财务部' UNION ALL
SELECT 2, 0, N'行政部' UNION ALL
SELECT 3, 0, N'业务部' UNION ALL
SELECT 4, 0, N'业务部' UNION ALL
SELECT 5, 4, N'销售部' UNION ALL
SELECT 6, 4, N'MIS' UNION ALL
SELECT 7, 6, N'UI' UNION ALL
SELECT 8, 6, N'软件开发' UNION ALL
SELECT 9, 8, N'内部开发'
GO

-- 查询指定部门下面的所有部门
DECLARE @Dept_name nvarchar(20)
SET @Dept_name = N'MIS'
;WITH
DEPTS AS(
 -- 定位点成员
 SELECT * FROM Dept
 WHERE name = @Dept_name
 UNION ALL
 -- 递归成员, 通过引用CTE自身与Dept基表JOIN实现递归
 SELECT A.*
 FROM Dept A, DEPTS B
 WHERE A.parent_id = B.id
)
SELECT * FROM DEPTS
GO

-- 删除演示环境
DROP TABLE Dept

----CTE的综合应用

USE tempdb
GO

-- 建立演示环境
CREATE TABLE Dept(
 id int PRIMARY KEY, 
 parent_id int,
 name nvarchar(20))
INSERT Dept
SELECT 0, 0, N'<全部>' UNION ALL
SELECT 1, 0, N'财务部' UNION ALL
SELECT 2, 0, N'行政部' UNION ALL
SELECT 3, 0, N'业务部' UNION ALL
SELECT 4, 0, N