SQltemp="...."
结果集
Ltyp Lname
1 A
1 B
1 C
2 D
2 E
上述结果是是通过SQltemp一系列复合语句求出来的结果值````在这基础上我 GROUP BY Ltyp 一下```可以得到 1 2,求一个函数能够得到以下效果`
1 A,B,C
2 D,E
因为SQL是一系列符合语句````希望高手帮我写一个可以把SQltemp语句做为参数传入的函数,需要合并的字段为Lname````非常感谢```
结果集
Ltyp Lname
1 A
1 B
1 C
2 D
2 E
上述结果是是通过SQltemp一系列复合语句求出来的结果值````在这基础上我 GROUP BY Ltyp 一下```可以得到 1 2,求一个函数能够得到以下效果`
1 A,B,C
2 D,E
因为SQL是一系列符合语句````希望高手帮我写一个可以把SQltemp语句做为参数传入的函数,需要合并的字段为Lname````非常感谢```
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
CREATE FUNCTION GET_STRING(@ID INT)
RETURNS VARCHAR(50)
AS
BEGIN
DECLARE @CLASS VARCHAR(50)
SELECT @CLASS=ISNULL(@CLASS+'/','')+LTRIM(B) FROM T WHERE A=@ID
RETURN @CLASS
END
--*******************************************************************************************
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) */
create table #SQltemp(Ltyp int, Lname varchar(10))
insert #SQltemp select 1 ,'A'
insert #SQltemp select 1 ,'B'
insert #SQltemp select 1 ,'C'
insert #SQltemp select 2 ,'D'
insert #SQltemp select 2 ,'E'
select Ltyp,stuff((select ','+Lname from #SQltemp b where a.Ltyp=b.Ltyp order by Lname for xml path('')),1,1,'')
from #SQltemp a
group by Ltyp Ltyp
----------- --------------
1 A,B,C
2 D,E(2 行受影响)
insert #TT select 1 ,'A'
insert #TT select 1 ,'B'
insert #TT select 1 ,'C'
insert #TT select 2 ,'D'
insert #TT select 2 ,'E'select Ltyp,
stuff((select ','+Lname from #TT b where a.Ltyp=b.Ltyp order by Lname for xml path('')),1,1,'')
from #TT a
group by Ltyp
SET @SQLtemp='
SELECT Ltyp=1, Lname=''A''
UNION ALL SELECT 1,''B''
UNION ALL SELECT 1,''C''
UNION ALL SELECT 2,''D''
UNION ALL SELECT 2,''E'''DECLARE @SQL VARCHAR(MAX)
SET @SQL='
;WITH CTE1 AS('+@SQLtemp+')
SELECT Ltyp
,Lname=STUFF((SELECT '',''+Lname FROM CTE1 AS x WHERE x.Ltyp=a.Ltyp FOR XML PATH('''')),1,1,'''')
FROM (SELECT DISTINCT Ltyp FROM CTE1 AS x) AS a'
EXEC(@SQL)