create table tb
(
a1 varchar(100),
b1 decimal(16,2)
)
insert into tb values('1001,1002',100.00)
insert into tb values('1001',120.00)
insert into tb values('1002',130.00)
SELECT B.a1,A.b1 FROM
(
SELECT b1, a1 = CONVERT(xml,'<root><v>' + REPLACE(a1, ',', '</v><v>') + '</v></root>') FROM tb
) A OUTER APPLY
(
SELECT a1 = N.v.value('.', 'varchar(100)') FROM A.a1.nodes('/root/v') N(v)
) B
/*
a1,b1
1001,100.00
1002,100.00
1001,120.00
1002,130.00
(4 行受影响)
/*
标题：简单数据拆分(version 2.0)
作者：爱新觉罗.毓华(十八年风雨,守得冰山雪莲花开)
时间：2010-05-07
地点：重庆航天职业学院
描述：
有表tb, 如下:
id value
----------- -----------
1 aa,bb
2 aaa,bbb,ccc
欲按id,分拆value列, 分拆后结果如下:
id value
----------- --------
1 aa
1 bb
2 aaa
2 bbb
2 ccc
*/
--1. 旧的解决方法(sql server 2000)
create table tb(id int,value varchar(30))
insert into tb values(1,'aa,bb')
insert into tb values(2,'aaa,bbb,ccc')
go
--方法1.使用临时表完成
SELECT TOP 8000 id = IDENTITY(int, 1, 1) INTO # FROM syscolumns a, syscolumns b
SELECT A.id, value = SUBSTRING(A.[value], B.id, CHARINDEX(',', A.[value] + ',', B.id) - B.id)
FROM tb A, # B
WHERE SUBSTRING(',' + A.[value], B.id, 1) = ','
DROP TABLE #
--方法2.如果数据量小，可不使用临时表
select a.id , value = substring(a.value , b.number , charindex(',' , a.value + ',' , b.number) - b.number)
from tb a join master..spt_values b
on b.type='p' and b.number between 1 and len(a.value)
where substring(',' + a.value , b.number , 1) = ','
--2. 新的解决方法(sql server 2005)
create table tb(id int,value varchar(30))
insert into tb values(1,'aa,bb')
insert into tb values(2,'aaa,bbb,ccc')
go
--方法1.使用xml完成
SELECT A.id, B.value FROM
(
SELECT id, [value] = CONVERT(xml,'<root><v>' + REPLACE([value], ',', '</v><v>') + '</v></root>') FROM tb
) A OUTER APPLY
(
SELECT value = N.v.value('.', 'varchar(100)') FROM A.[value].nodes('/root/v') N(v)
) B
--方法2.使用CTE完成
;with tt as
(select id,[value]=cast(left([value],charindex(',',[value]+',')-1) as nvarchar(100)),Split=cast(stuff([value]+',',1,charindex(',',[value]+','),'') as nvarchar(100)) from tb
union all
select id,[value]=cast(left(Split,charindex(',',Split)-1) as nvarchar(100)),Split= cast(stuff(Split,1,charindex(',',Split),'') as nvarchar(100)) from tt where split>''
)
select id,[value] from tt order by id option (MAXRECURSION 0)
DROP TABLE tb
/*
id value
----------- ------------------------------
1 aa
1 bb
2 aaa
2 bbb
2 ccc
(5 行受影响)
*/
--参考
拆分表:
--> --> (Roy)生成測試數據
if not object_id('Tab') is null
drop table Tab
Go
Create table Tab([Col1] int,[COl2] nvarchar(5))
Insert Tab
select 1,N'a,b,c' union all
select 2,N'd,e' union all
select 3,N'f'
Go
--SQL2000用辅助表:
if object_id('Tempdb..#Num') is not null
drop table #Num
go
select top 100 ID=Identity(int,1,1) into #Num from syscolumns a,syscolumns b
Select
a.Col1,COl2=substring(a.Col2,b.ID,charindex(',',a.Col2+',',b.ID)-b.ID)
from
Tab a,#Num b
where
charindex(',',','+a.Col2,b.ID)=b.ID --也可用 substring(','+a.COl2,b.ID,1)=','
--2000不使用辅助表
Select
a.Col1,COl2=substring(a.Col2,b.number,charindex(',',a.Col2+',',b.number)-b.number)
from
Tab a join master..spt_values b
ON B.type='p' AND B.number BETWEEN 1 AND LEN(A.col2)
where
substring(','+a.COl2,b.number,1)=','
SQL2005用Xml:
select
a.COl1,b.Col2
from
(select Col1,COl2=convert(xml,'<root><v>'+replace(COl2,',','</v><v>')+'</v></root>') from Tab)a
outer apply
(select Col2=C.v.value('.','nvarchar(100)') from a.COl2.nodes('/root/v')C(v))b
SQL05用CTE:
;with roy as
(select Col1,COl2=cast(left(Col2,charindex(',',Col2+',')-1) as nvarchar(100)),Split=cast(stuff(COl2+',',1,charindex(',',Col2+','),'') as nvarchar(100)) from Tab
union all
select Col1,COl2=cast(left(Split,charindex(',',Split)-1) as nvarchar(100)),Split= cast(stuff(Split,1,charindex(',',Split),'') as nvarchar(100)) from Roy where split>''
)
select COl1,COl2 from roy order by COl1 option (MAXRECURSION 0)
生成结果:
/*
Col1 COl2
----------- -----
1 a
1 b
1 c
2 d
2 e
3 f
*/
create table tb(a1 varchar(20),b1 decimal(18,2))
insert into tb values('1001,1002', 100.00)
insert into tb values('1001', 120.00)
insert into tb values('1002', 130.00)
go
SELECT TOP 8000 id = IDENTITY(int, 1, 1) INTO # FROM syscolumns a, syscolumns b
SELECT a1 = SUBSTRING(A.a1, B.id, CHARINDEX(',', A.a1 + ',', B.id) - B.id) , a.b1
FROM tb A, # B
WHERE SUBSTRING(',' + A.a1, B.id, 1) = ','
DROP TABLE #
drop table tb
/*
a1 b1
-------------------- --------------------
1001 100.00
1002 100.00
1001 120.00
1002 130.00
（所影响的行数为 4 行）
*/
create table tb(a1 varchar(20),b1 decimal(18,2))
insert into tb values('1001,1002', 100.00)
insert into tb values('1001', 120.00)
insert into tb values('1002', 130.00)
go
select a1 = substring(a.a1 , b.number , charindex(',' , a.a1 + ',' , b.number) - b.number) , b1
from tb a join master..spt_values b
on b.type='p' and b.number between 1 and len(a.a1)
where substring(',' + a.a1 , b.number , 1) = ','
drop table tb
/*
a1 b1
-------------------- --------------------
1001 100.00
1002 100.00
1001 120.00
1002 130.00
（所影响的行数为 4 行）
*/
create table tb(a1 varchar(20),b1 decimal(18,2))
insert into tb values('1001,1002', 100.00)
insert into tb values('1001', 120.00)
insert into tb values('1002', 130.00)
go
SELECT B.a1 , a.b1 FROM
(
SELECT b1, a1 = CONVERT(xml,'<root><v>' + REPLACE(a1, ',', '</v><v>') + '</v></root>') FROM tb
) A OUTER APPLY
(
SELECT a1 = N.v.value('.', 'varchar(100)') FROM A.a1.nodes('/root/v') N(v)
) B
drop table tb
/*
a1 b1
---------------------------------------------------------------------------------------------------- ---------------------------------------
1001 100.00
1002 100.00
1001 120.00
1002 130.00
(4 行受影响)
*/
