如何从表1得到表2 SQL遍历

[kubalila]

表一 自动编号 母件ID 母件名称 子件ID 子件名称
1 1001 A 1002 B
2 1001 A 1003 C
3 1002 B 1004 D
4 1003 C 1005 E
5 1004 D 1006 F
6 1007 G 1008 H
7 1009 I 1010 J
8 1009 I 1011 K


表二 层次 ID 名称
+ 1001 A
++ 1002 B
+++ 1004 D
++++ 1006 F
++ 1003 C
+++ 1005 E
+ 1007 G
++ 1008 H
+ 1009 I
++ 1010 J
++ 1011 K


母件下面可能对应N个子件
其子件可能又是母件
例 1001 下有两个一级的子件 1002 1003
1002 是一个子件，同时 又是1004的母件，而1004同时又是1006的母件

其它类推，层次不定

[开着拖拉机泡妞]

BOM按节点排序应用实例 
--------------------------------------------------------------------------

--  Author : htl258(Tony)

--  Date   : 2010-04-23 02:37:28

--  Version:Microsoft SQL Server 2008 (RTM) - 10.0.1600.22 (Intel X86) 

--          Jul  9 2008 14:43:34 

--          Copyright (c) 1988-2008 Microsoft Corporation

--          Developer Edition on Windows NT 5.1 <X86> (Build 2600: Service Pack 3)

--  Subject: BOM按节点排序应用实例

--------------------------------------------------------------------------

 

--实例1:

--> 生成测试数据表:tb

 

IF NOT OBJECT_ID('[tb]') IS NULL

    DROP TABLE [tb]

GO

CREATE TABLE [tb]([id] INT,[code] NVARCHAR(10),[pid] INT,[name] NVARCHAR(10))

INSERT [tb]

SELECT 1,'01',0,N'服装' UNION ALL

SELECT 2,'01',1,N'男装' UNION ALL

SELECT 3,'01',2,N'西装' UNION ALL

SELECT 4,'01',3,N'全毛' UNION ALL

SELECT 5,'02',3,N'化纤' UNION ALL

SELECT 6,'02',2,N'休闲装' UNION ALL

SELECT 7,'02',1,N'女装' UNION ALL

SELECT 8,'01',7,N'套装' UNION ALL

SELECT 9,'02',7,N'职业装' UNION ALL

SELECT 10,'03',7,N'休闲装' UNION ALL

SELECT 11,'04',7,N'西装' UNION ALL

SELECT 12,'01',11,N'全毛' UNION ALL

SELECT 13,'02',11,N'化纤' UNION ALL

SELECT 14,'05',7,N'休闲装'

GO

--SELECT * FROM [tb]

 

-->SQL查询如下:

 

;WITH T AS

(

    SELECT CAST(CODE AS VARCHAR(20)) AS CODE,*,

        CAST(ID AS VARBINARY(MAX)) AS px 

    FROM tb AS A

    WHERE NOT EXISTS(SELECT * FROM tb WHERE id=A.pid)

    UNION ALL 

    SELECT CAST(B.CODE+A.CODE AS VARCHAR(20)),A.*,

         CAST(B.px+CAST(A.ID AS VARBINARY) AS VARBINARY(MAX))    

    FROM tb AS A

        JOIN T AS B

           ON A.pid=B.id

)

SELECT Code,Name FROM T 

ORDER BY px

/*

Code                 Name

-------------------- ----------

01                   服装

0101                 男装

010101               西装

01010101             全毛

01010102             化纤

010102               休闲装

0102                 女装

010201               套装

010202               职业装

010203               休闲装

010204               西装

01020401             全毛

01020402             化纤

010205               休闲装

 

(14 行受影响)

*/

 

--实例2:

--> 生成测试数据表:tb

IF NOT OBJECT_ID('[tb]') IS NULL
    DROP TABLE [tb]
GO
CREATE TABLE [tb]([id] INT,[parentid] INT,[categoryname] NVARCHAR(10))
INSERT [tb]
SELECT 1,0,'test1' UNION ALL
SELECT 2,0,'test2' UNION ALL
SELECT 3,1,'test1.1' UNION ALL
SELECT 4,2,'test2.1' UNION ALL
SELECT 5,3,'test1.1.1' UNION ALL
SELECT 6,1,'test1.2'
GO
--SELECT * FROM [tb]

-->SQL查询如下:
;WITH T AS
(
    SELECT *,CAST(ID AS VARBINARY(MAX)) AS px 
    FROM tb AS A
    WHERE NOT EXISTS(SELECT * FROM tb WHERE id=A.[parentid])
    UNION ALL 
    SELECT A.*,CAST(B.px+CAST(A.ID AS VARBINARY) AS VARBINARY(MAX))  
    FROM tb AS A
        JOIN T AS B
           ON A.[parentid]=B.id
)
SELECT [id],[parentid],[categoryname] FROM T 
ORDER BY px
/*
id          parentid    categoryname
----------- ----------- ------------
1           0           test1
3           1           test1.1
5           3           test1.1.1
6           1           test1.2
2           0           test2
4           2           test2.1

(6 行受影响)
*/



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[快溜]

用递归查询。