ID A
1 a,b,c
2 b,c,a
3 c,b,a
4 aa,bb,cc
5 bb,aa,cc
6 cc,bb,aa
7 n,b,h现在我要查询出来的结果 这样1 a,b,c
4 aa,bb,cc
7 n,b,h
1 a,b,c
2 b,c,a
3 c,b,a
4 aa,bb,cc
5 bb,aa,cc
6 cc,bb,aa
7 n,b,h现在我要查询出来的结果 这样1 a,b,c
4 aa,bb,cc
7 n,b,h
-- Author :fredrickhu(小F 向高手学习)
-- Date :2009-08-10 10:20:28
----------------------------------------------------------------
--> 测试数据:[tb]
if object_id('[tb]') is not null drop table [tb]
go
create table [tb]([ID] int,[A] varchar(8))
insert [tb]
select 1,'a,b,c' union all
select 2,'b,c,a' union all
select 3,'c,b,a' union all
select 4,'aa,bb,cc' union all
select 5,'bb,aa,cc' union all
select 6,'cc,bb,aa' union all
select 7,'n,b,h'
--------------开始查询--------------------------select * from [tb] where [id] in(1,4,7)
----------------结果----------------------------
/*
ID A
----------- --------
1 a,b,c
4 aa,bb,cc
7 n,b,h(所影响的行数为 3 行)*/
分拆列值 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)
select a.id, substring(a.[value], b.number, charindex(',', a.[value] + ',', b.number) - b.number)
FROM tb a, master..spt_values b
WHERE b.type='p' and 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
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 DROP TabLE tb /*
id value
----------- ------------------------------
1 aa
1 bb
2 aaa
2 bbb
2 ccc (5 行受影响)
*/
--******************************************************************
-- 合并列值
--******************************************************************
表结构,数据如下:
id value
----- ------
1 aa
1 bb
2 aaa
2 bbb
2 ccc 需要得到结果:
id values
------ -----------
1 aa,bb
2 aaa,bbb,ccc
即:group by id, 求 value 的和(字符串相加) 1. 旧的解决方法(在sql server 2000中只能用函数解决。)
--===================================================================
create table tb(id int, value varchar(10))
insert into tb values(1, 'aa')
insert into tb values(1, 'bb')
insert into tb values(2, 'aaa')
insert into tb values(2, 'bbb')
insert into tb values(2, 'ccc')
go
--1. 创建处理函数
CREATE FUNCTION dbo.f_strUnite(@id int)
RETURNS varchar(8000)
AS
BEGIN
DECLARE @str varchar(8000)
SET @str = ''
SELECT @str = @str + ',' + value FROM tb WHERE id=@id
RETURN STUFF(@str, 1, 1, '')
END
GO
-- 调用函数
SELECt id, value = dbo.f_strUnite(id) FROM tb GROUP BY id
drop table tb
drop function dbo.f_strUnite
go
/*
id value
----------- -----------
1 aa,bb
2 aaa,bbb,ccc
(所影响的行数为 2 行)
*/
--===================================================================================
2. 新的解决方法(在sql server 2005中用OUTER APPLY等解决。)
create table tb(id int, value varchar(10))
insert into tb values(1, 'aa')
insert into tb values(1, 'bb')
insert into tb values(2, 'aaa')
insert into tb values(2, 'bbb')
insert into tb values(2, 'ccc')
go
-- 查询处理
SELECT * FROM(SELECT DISTINCT id FROM tb)A OUTER APPLY(
SELECT [values]= STUFF(REPLACE(REPLACE(
(
SELECT value FROM tb N
WHERE id = A.id
FOR XML AUTO
), ' <N value="', ','), '"/>', ''), 1, 1, '')
)N
drop table tb /*
id values
----------- -----------
1 aa,bb
2 aaa,bbb,ccc (2 行受影响)
*/ --SQL2005中的方法2
create table tb(id int, value varchar(10))
insert into tb values(1, 'aa')
insert into tb values(1, 'bb')
insert into tb values(2, 'aaa')
insert into tb values(2, 'bbb')
insert into tb values(2, 'ccc')
go select id, [values]=stuff((select ','+[value] from tb t where id=tb.id
for xml path('')), 1, 1, '')
from tb
group by id /*
id values
----------- --------------------
1 aa,bb
2 aaa,bbb,ccc (2 row(s) affected) */ drop table tb
Drop table [tb]
Go
Create table [tb]([ID] int,[A] nvarchar(8))
Insert tb
Select 1,'a,b,c' union all
Select 2,'b,c,a' union all
Select 3,'c,b,a' union all
Select 4,'aa,bb,cc' union all
Select 5,'bb,aa,cc' union all
Select 6,'cc,bb,aa' union all
Select 7,'n,b,h'
Go
--Select * from tb-->SQL查询如下:
;with t as
(
select
a.id,
a=substring(a.a, b.number, charindex(',', a.a + ',', b.number) - b.number)
from tb a,master..spt_values b
where b.number>0
and b.type='p'
and substring(',' + a.a,b.number,1) = ','
),t1 as
(
select distinct id,
stuff((select ','+a from t where id=a.id order by a for xml path('')),1,1,'') a
from t a
)
select *
from t1 a
where not exists(
select 1
from t1
where a=a.a
and id<a.id)
/*
id a
----------- ----------------
1 a,b,c
4 aa,bb,cc
7 b,h,n(3 行受影响)*/
Drop table [tb]
Go
Create table [tb]([ID] int,[A] nvarchar(8))
Insert tb
Select 1,'a,b,c' union all
Select 2,'b,c,a' union all
Select 3,'c,b,a' union all
Select 4,'aa,bb,cc' union all
Select 5,'bb,aa,cc' union all
Select 6,'cc,bb,aa' union all
Select 7,'n,b,h'
Go
--Select * from tb-->SQL查询如下:
;with t as
(
select
a.id,
a=substring(a.a, b.number, charindex(',', a.a + ',', b.number) - b.number)
from tb a,master..spt_values b
where b.number>0
and b.type='p'
and substring(',' + a.a,b.number,1) = ','
),t1 as
(
select distinct id,
stuff((select ','+a from t where id=a.id order by a for xml path('')),1,1,'') a
from t a
)
select *
from tb
where exists(
select *
from t1 a
where not exists(
select 1
from t1
where a=a.a
and id<a.id)
and tb.id=a.id)
/*
ID A
----------- --------
1 a,b,c
4 aa,bb,cc
7 n,b,h(3 行受影响)*/这样才是对的.