--1. 创建处理函数 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 CREATE FUNCTION dbo.f_str(@id int) RETURNS varchar(8000) AS BEGIN DECLARE @r varchar(8000) SET @r = '' SELECT @r = @r + ',' + value FROM tb WHERE id=@id RETURN STUFF(@r, 1, 1, '') END GO -- 调用函数 SELECt id, value = dbo.f_str(id) FROM tb GROUP BY id drop table tb drop function dbo.f_str
SQL code问题描述: 无论是在sql 2000,还是在 sql 2005 中,都没有提供字符串的聚合函数, 所以,当我们在处理下列要求时,会比较麻烦: 有表tb, 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-- 1. 创建处理函数 CREATE FUNCTION dbo.f_str(@id int) RETURNS varchar(8000) AS BEGIN DECLARE @r varchar(8000) SET @r = '' SELECT @r = @r + ',' + value FROM tb WHERE id=@id RETURN STUFF(@r, 1, 1, '') END GO -- 调用函数SELECt id, values=dbo.f_str(id) FROM tb GROUP BY id-- 2. 新的解决方法 -- 示例数据 DECLARE @t TABLE(id int, value varchar(10)) INSERT @t SELECT 1, 'aa' UNION ALL SELECT 1, 'bb' UNION ALL SELECT 2, 'aaa' UNION ALL SELECT 2, 'bbb' UNION ALL SELECT 2, 'ccc'-- 查询处理 SELECT * FROM( SELECT DISTINCT id FROM @t )A OUTER APPLY( SELECT [values]= STUFF(REPLACE(REPLACE( ( SELECT value FROM @t N WHERE id = A.id FOR XML AUTO ), '<N value="', ','), '"/>', ''), 1, 1, '') )N/*--结果 id values ----------- ---------------- 1 aa,bb 2 aaa,bbb,ccc (2 行受影响) --*/--各种字符串分函数--3.3.1 使用游标法进行字符串合并处理的示例。 --处理的数据 CREATE TABLE tb(col1 varchar(10),col2 int) INSERT tb SELECT 'a',1 UNION ALL SELECT 'a',2 UNION ALL SELECT 'b',1 UNION ALL SELECT 'b',2 UNION ALL SELECT 'b',3--合并处理 --定义结果集表变量 DECLARE @t TABLE(col1 varchar(10),col2 varchar(100))--定义游标并进行合并处理 DECLARE tb CURSOR LOCAL FOR SELECT col1,col2 FROM tb ORDER BY col1,col2 DECLARE @col1_old varchar(10),@col1 varchar(10),@col2 int,@s varchar(100) OPEN tb FETCH tb INTO @col1,@col2 SELECT @col1_old=@col1,@s='' WHILE @@FETCH_STATUS=0 BEGIN IF @col1=@col1_old SELECT @s=@s+','+CAST(@col2 as varchar) ELSE BEGIN INSERT @t VALUES(@col1_old,STUFF(@s,1,1,'')) SELECT @s=','+CAST(@col2 as varchar),@col1_old=@col1 END FETCH tb INTO @col1,@col2 END INSERT @t VALUES(@col1_old,STUFF(@s,1,1,'')) CLOSE tb DEALLOCATE tb --显示结果并删除测试数据 SELECT * FROM @t DROP TABLE tb /*--结果 col1 col2 ---------- ----------- a 1,2 b 1,2,3 --*/ GO /*==============================================*/ --3.3.2 使用用户定义函数,配合SELECT处理完成字符串合并处理的示例 --处理的数据 CREATE TABLE tb(col1 varchar(10),col2 int) INSERT tb SELECT 'a',1 UNION ALL SELECT 'a',2 UNION ALL SELECT 'b',1 UNION ALL SELECT 'b',2 UNION ALL SELECT 'b',3 GO--合并处理函数 CREATE FUNCTION dbo.f_str(@col1 varchar(10)) RETURNS varchar(100) AS BEGIN DECLARE @re varchar(100) SET @re='' SELECT @re=@re+','+CAST(col2 as varchar) FROM tb WHERE col1=@col1 RETURN(STUFF(@re,1,1,'')) END GO--调用函数 SELECT col1,col2=dbo.f_str(col1) FROM tb GROUP BY col1 --删除测试 DROP TABLE tb DROP FUNCTION f_str /*--结果 col1 col2 ---------- ----------- a 1,2 b 1,2,3 --*/ GO/*==============================================*/ --3.3.3 使用临时表实现字符串合并处理的示例 --处理的数据 CREATE TABLE tb(col1 varchar(10),col2 int) INSERT tb SELECT 'a',1 UNION ALL SELECT 'a',2 UNION ALL SELECT 'b',1 UNION ALL SELECT 'b',2 UNION ALL SELECT 'b',3--合并处理 SELECT col1,col2=CAST(col2 as varchar(100)) INTO #t FROM tb ORDER BY col1,col2 DECLARE @col1 varchar(10),@col2 varchar(100) UPDATE #t SET @col2=CASE WHEN @col1=col1 THEN @col2+','+col2 ELSE col2 END, @col1=col1, col2=@col2 SELECT * FROM #t /*--更新处理后的临时表 col1 col2 ---------- ------------- a 1 a 1,2 b 1 b 1,2 b 1,2,3 --*/ --得到最终结果 SELECT col1,col2=MAX(col2) FROM #t GROUP BY col1 /*--结果 col1 col2 ---------- ----------- a 1,2 b 1,2,3 --*/ --删除测试 DROP TABLE tb,#t GO /*==============================================*/--3.3.4.1 每组 <=2 条记录的合并 --处理的数据 CREATE TABLE tb(col1 varchar(10),col2 int) INSERT tb SELECT 'a',1 UNION ALL SELECT 'a',2 UNION ALL SELECT 'b',1 UNION ALL SELECT 'b',2 UNION ALL SELECT 'c',3--合并处理 SELECT col1, col2=CAST(MIN(col2) as varchar) +CASE WHEN COUNT(*)=1 THEN '' ELSE ','+CAST(MAX(col2) as varchar) END FROM tb GROUP BY col1 DROP TABLE tb /*--结果 col1 col2 ---------- ---------- a 1,2 b 1,2 c 3 --*/--3.3.4.2 每组 <=3 条记录的合并 --处理的数据 CREATE TABLE tb(col1 varchar(10),col2 int) INSERT tb SELECT 'a',1 UNION ALL SELECT 'a',2 UNION ALL SELECT 'b',1 UNION ALL SELECT 'b',2 UNION ALL SELECT 'b',3 UNION ALL SELECT 'c',3--合并处理 SELECT col1, col2=CAST(MIN(col2) as varchar) +CASE WHEN COUNT(*)=3 THEN ',' +CAST((SELECT col2 FROM tb WHERE col1=a.col1 AND col2 NOT IN(MAX(a.col2),MIN(a.col2))) as varchar) ELSE '' END +CASE WHEN COUNT(*)>=2 THEN ','+CAST(MAX(col2) as varchar) ELSE '' END FROM tb a GROUP BY col1 DROP TABLE tb /*--结果 col1 col2 ---------- ------------ a 1,2 b 1,2,3 c 3 --*/ GO if not object_id('A') is null drop table A Go Create table A([id] int,[cname] nvarchar(2)) Insert A select 1,N'张三' union all select 2,N'李四' union all select 3,N'王五' union all select 4,N'蔡六' Go --> -->
if not object_id('B') is null drop table B Go Create table B([id] int,[cname] nvarchar(5)) Insert B select 1,N'1,2,3' union all select 2,N'3,4' Go create function F_str(@cname nvarchar(100)) returns nvarchar(100) as begin select @cname=replace(@cname,ID,[cname]) from A where patindex('%,'+rtrim(ID)+',%',','+@cname+',')>0 return @cname end go select [id],dbo.F_str([cname])[cname] from Bid cname ----------- ---------------------------------------------------------------------------------------------------- 1 张三,李四,王五 2 王五,蔡六(2 個資料列受到影響)
if object_id('T')is not null drop table t if object_id('f')IS NOT NULL DROP FUNCTION F go create table T(id int,S varchar(10)) insert into T select 1,'ai' union all select 1,'be' union all select 1,'ch' union all select 1,'gk' union all select 2,'hi' union all select 2,'ky' union all select 2,'ft' union all select 3,'bf' union all select 3,'mu' go create function F(@id int) returns varchar(100) as begin declare @str varchar(100) set @str='' select @str=isnull(@str,'')+','+s from t where id=@id return stuff(@str,1,1,'') end go select id valu, names=dbo.f(id) from t group by id 1 ai,be,ch,gk 2 hi,ky,ft 3 bf,mu
DECLARE @t TABLE(id INT,v VARCHAR(20)) INSERT @t SELECT 1, 'ai' UNION ALL SELECT 1, 'be' UNION ALL SELECT 1, 'ch' UNION ALL SELECT 1, 'gk' UNION ALL SELECT 2, 'hi' UNION ALL SELECT 2, 'ky' UNION ALL SELECT 2, 'ft' UNION ALL SELECT 3 ,'bf' UNION ALL SELECT 3, 'mu' SELECT * FROM (SELECT DISTINCT id FROM @t) a CROSS APPLY (SELECT v=STUFF( (SELECT ',' + v FROM @t WHERE id=a.id FOR XML PATH(''),TYPE).value('/','VARCHAR(1000)') ,1,1,'') ) b
SELECT * FROM( SELECT DISTINCT id FROM @t )A OUTER APPLY( SELECT [values]= STUFF(REPLACE(REPLACE( ( SELECT value FROM @t N WHERE id = A.id FOR XML AUTO ), '<N value="', ','), '"/>', ''), 1, 1, '') )N
create table tt ( id int, value varchar(10) ) insert into tt values(1, 'aa') insert into tt values(1, 'bb') insert into tt values(2, 'aaa') insert into tt values(2, 'bbb') insert into tt values(2, 'ccc') go CREATE FUNCTION dbo.f_str(@id int) RETURNS varchar(8000) AS BEGIN DECLARE @r varchar(8000) SET @r='' SELECT @r=@r+','+value FROM tt WHERE id=@id RETURN STUFF(@r,1,1,'') END GO -- 调用函数 SELECt id,value=dbo.f_str(id) FROM tt GROUP BY id
合并列值 原著:邹建 改编:爱新觉罗.毓华(十八年风雨,守得冰山雪莲花开) 2007-12-16 广东深圳表结构,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。) --1. 创建处理函数 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') goCREATE FUNCTION dbo.f_str(@id int) RETURNS varchar(8000) AS BEGIN DECLARE @r varchar(8000) SET @r = '' SELECT @r = @r + ',' + value FROM tb WHERE id=@id RETURN STUFF(@r, 1, 1, '') END GO-- 调用函数 SELECt id, value = dbo.f_str(id) FROM tb GROUP BY iddrop table tb drop function dbo.f_str/* id value ----------- ----------- 1 aa,bb 2 aaa,bbb,ccc (所影响的行数为 2 行) */--2、另外一种函数. 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--创建一个合并的函数 create function f_hb(@id int) returns varchar(8000) as begin declare @str varchar(8000) set @str = '' select @str = @str + ',' + cast(value as varchar) from tb where id = @id set @str = right(@str , len(@str) - 1) return(@str) End go--调用自定义函数得到结果: select distinct id ,dbo.f_hb(id) as value from tbdrop table tb drop function dbo.f_hb/* 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') goselect 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
CREATE TABLE #A (S_NO VARCHAR(50),S_NAME VARCHAR(50)) INSERT INTO #A SELECT '001','A' INSERT INTO #A SELECT '001','B' INSERT INTO #A SELECT '001','C' INSERT INTO #A SELECT '001','D' INSERT INTO #A SELECT '002','AA' INSERT INTO #A SELECT '002','AC' INSERT INTO #A SELECT '003','SS' INSERT INTO #A SELECT '003','AA' INSERT INTO #A SELECT '003','GH'CREATE TABLE #TEMP (S_NO VARCHAR(50),S_NAME VARCHAR(50),S_TEXT VARCHAR(1000)) INSERT INTO #TEMP SELECT S_NO,MIN(S_NAME),MIN(S_NAME) FROM #A GROUP BY S_NOWHILE (SELECT COUNT(*) FROM #TEMP)<(SELECT COUNT(*) FROM #A) BEGIN UPDATE #TEMP SET S_TEXT=(S_TEXT+','+B.S_NAME)FROM #TEMP A LEFT JOIN (SELECT S_NO,MIN(S_NAME)S_NAME FROM #A WHERE S_NO+S_NAME NOT IN (SELECT S_NO+S_NAME FROM #TEMP) GROUP BY S_NO)B ON A.S_NO=B.S_NO WHERE ISNULL(B.S_NAME,'')<>'' AND ISNULL(S_TEXT,'')<>''INSERT #TEMP SELECT S_NO,MIN(S_NAME)S_NAME,'' FROM #A WHERE S_NO+S_NAME NOT IN (SELECT S_NO+S_NAME FROM #TEMP) GROUP BY S_NOENDSELECT S_NO,S_TEXT FROM #TEMP WHERE ISNULL(S_TEXT,'')<>''DROP TABLE #TEMP DROP TABLE #A
--1. 创建处理函数
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 CREATE FUNCTION dbo.f_str(@id int)
RETURNS varchar(8000)
AS
BEGIN
DECLARE @r varchar(8000)
SET @r = ''
SELECT @r = @r + ',' + value FROM tb WHERE id=@id
RETURN STUFF(@r, 1, 1, '')
END
GO -- 调用函数
SELECt id, value = dbo.f_str(id) FROM tb GROUP BY id drop table tb
drop function dbo.f_str
无论是在sql 2000,还是在 sql 2005 中,都没有提供字符串的聚合函数,
所以,当我们在处理下列要求时,会比较麻烦:
有表tb, 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-- 1. 创建处理函数
CREATE FUNCTION dbo.f_str(@id int)
RETURNS varchar(8000)
AS
BEGIN
DECLARE @r varchar(8000)
SET @r = ''
SELECT @r = @r + ',' + value
FROM tb
WHERE id=@id
RETURN STUFF(@r, 1, 1, '')
END
GO
-- 调用函数SELECt id, values=dbo.f_str(id)
FROM tb
GROUP BY id-- 2. 新的解决方法
-- 示例数据
DECLARE @t TABLE(id int, value varchar(10))
INSERT @t SELECT 1, 'aa'
UNION ALL SELECT 1, 'bb'
UNION ALL SELECT 2, 'aaa'
UNION ALL SELECT 2, 'bbb'
UNION ALL SELECT 2, 'ccc'-- 查询处理
SELECT *
FROM(
SELECT DISTINCT
id
FROM @t
)A
OUTER APPLY(
SELECT
[values]= STUFF(REPLACE(REPLACE(
(
SELECT value FROM @t N
WHERE id = A.id
FOR XML AUTO
), '<N value="', ','), '"/>', ''), 1, 1, '')
)N/*--结果
id values
----------- ----------------
1 aa,bb
2 aaa,bbb,ccc
(2 行受影响)
--*/--各种字符串分函数--3.3.1 使用游标法进行字符串合并处理的示例。
--处理的数据
CREATE TABLE tb(col1 varchar(10),col2 int)
INSERT tb SELECT 'a',1
UNION ALL SELECT 'a',2
UNION ALL SELECT 'b',1
UNION ALL SELECT 'b',2
UNION ALL SELECT 'b',3--合并处理
--定义结果集表变量
DECLARE @t TABLE(col1 varchar(10),col2 varchar(100))--定义游标并进行合并处理
DECLARE tb CURSOR LOCAL
FOR
SELECT col1,col2 FROM tb ORDER BY col1,col2
DECLARE @col1_old varchar(10),@col1 varchar(10),@col2 int,@s varchar(100)
OPEN tb
FETCH tb INTO @col1,@col2
SELECT @col1_old=@col1,@s=''
WHILE @@FETCH_STATUS=0
BEGIN
IF @col1=@col1_old
SELECT @s=@s+','+CAST(@col2 as varchar)
ELSE
BEGIN
INSERT @t VALUES(@col1_old,STUFF(@s,1,1,''))
SELECT @s=','+CAST(@col2 as varchar),@col1_old=@col1
END
FETCH tb INTO @col1,@col2
END
INSERT @t VALUES(@col1_old,STUFF(@s,1,1,''))
CLOSE tb
DEALLOCATE tb
--显示结果并删除测试数据
SELECT * FROM @t
DROP TABLE tb
/*--结果
col1 col2
---------- -----------
a 1,2
b 1,2,3
--*/
GO
/*==============================================*/
--3.3.2 使用用户定义函数,配合SELECT处理完成字符串合并处理的示例
--处理的数据
CREATE TABLE tb(col1 varchar(10),col2 int)
INSERT tb SELECT 'a',1
UNION ALL SELECT 'a',2
UNION ALL SELECT 'b',1
UNION ALL SELECT 'b',2
UNION ALL SELECT 'b',3
GO--合并处理函数
CREATE FUNCTION dbo.f_str(@col1 varchar(10))
RETURNS varchar(100)
AS
BEGIN
DECLARE @re varchar(100)
SET @re=''
SELECT @re=@re+','+CAST(col2 as varchar)
FROM tb
WHERE col1=@col1
RETURN(STUFF(@re,1,1,''))
END
GO--调用函数
SELECT col1,col2=dbo.f_str(col1) FROM tb GROUP BY col1
--删除测试
DROP TABLE tb
DROP FUNCTION f_str
/*--结果
col1 col2
---------- -----------
a 1,2
b 1,2,3
--*/
GO/*==============================================*/
--3.3.3 使用临时表实现字符串合并处理的示例
--处理的数据
CREATE TABLE tb(col1 varchar(10),col2 int)
INSERT tb SELECT 'a',1
UNION ALL SELECT 'a',2
UNION ALL SELECT 'b',1
UNION ALL SELECT 'b',2
UNION ALL SELECT 'b',3--合并处理
SELECT col1,col2=CAST(col2 as varchar(100))
INTO #t FROM tb
ORDER BY col1,col2
DECLARE @col1 varchar(10),@col2 varchar(100)
UPDATE #t SET
@col2=CASE WHEN @col1=col1 THEN @col2+','+col2 ELSE col2 END,
@col1=col1,
col2=@col2
SELECT * FROM #t
/*--更新处理后的临时表
col1 col2
---------- -------------
a 1
a 1,2
b 1
b 1,2
b 1,2,3
--*/
--得到最终结果
SELECT col1,col2=MAX(col2) FROM #t GROUP BY col1
/*--结果
col1 col2
---------- -----------
a 1,2
b 1,2,3
--*/
--删除测试
DROP TABLE tb,#t
GO
/*==============================================*/--3.3.4.1 每组 <=2 条记录的合并
--处理的数据
CREATE TABLE tb(col1 varchar(10),col2 int)
INSERT tb SELECT 'a',1
UNION ALL SELECT 'a',2
UNION ALL SELECT 'b',1
UNION ALL SELECT 'b',2
UNION ALL SELECT 'c',3--合并处理
SELECT col1,
col2=CAST(MIN(col2) as varchar)
+CASE
WHEN COUNT(*)=1 THEN ''
ELSE ','+CAST(MAX(col2) as varchar)
END
FROM tb
GROUP BY col1
DROP TABLE tb
/*--结果
col1 col2
---------- ----------
a 1,2
b 1,2
c 3
--*/--3.3.4.2 每组 <=3 条记录的合并
--处理的数据
CREATE TABLE tb(col1 varchar(10),col2 int)
INSERT tb SELECT 'a',1
UNION ALL SELECT 'a',2
UNION ALL SELECT 'b',1
UNION ALL SELECT 'b',2
UNION ALL SELECT 'b',3
UNION ALL SELECT 'c',3--合并处理
SELECT col1,
col2=CAST(MIN(col2) as varchar)
+CASE
WHEN COUNT(*)=3 THEN ','
+CAST((SELECT col2 FROM tb WHERE col1=a.col1 AND col2 NOT IN(MAX(a.col2),MIN(a.col2))) as varchar)
ELSE ''
END
+CASE
WHEN COUNT(*)>=2 THEN ','+CAST(MAX(col2) as varchar)
ELSE ''
END
FROM tb a
GROUP BY col1
DROP TABLE tb
/*--结果
col1 col2
---------- ------------
a 1,2
b 1,2,3
c 3
--*/
GO
if not object_id('A') is null
drop table A
Go
Create table A([id] int,[cname] nvarchar(2))
Insert A
select 1,N'张三' union all
select 2,N'李四' union all
select 3,N'王五' union all
select 4,N'蔡六'
Go
--> -->
if not object_id('B') is null
drop table B
Go
Create table B([id] int,[cname] nvarchar(5))
Insert B
select 1,N'1,2,3' union all
select 2,N'3,4'
Go
create function F_str(@cname nvarchar(100))
returns nvarchar(100)
as
begin
select @cname=replace(@cname,ID,[cname]) from A where patindex('%,'+rtrim(ID)+',%',','+@cname+',')>0
return @cname
end
go
select [id],dbo.F_str([cname])[cname] from Bid cname
----------- ----------------------------------------------------------------------------------------------------
1 张三,李四,王五
2 王五,蔡六(2 個資料列受到影響)
if object_id('T')is not null
drop table t
if object_id('f')IS NOT NULL
DROP FUNCTION F
go
create table T(id int,S varchar(10))
insert into T select 1,'ai'
union all select 1,'be'
union all select 1,'ch'
union all select 1,'gk'
union all select 2,'hi'
union all select 2,'ky'
union all select 2,'ft'
union all select 3,'bf'
union all select 3,'mu'
go
create function F(@id int)
returns varchar(100)
as
begin
declare @str varchar(100)
set @str=''
select @str=isnull(@str,'')+','+s from t where id=@id
return stuff(@str,1,1,'')
end
go
select id valu, names=dbo.f(id) from t group by id 1 ai,be,ch,gk
2 hi,ky,ft
3 bf,mu
INSERT @t SELECT 1, 'ai'
UNION ALL SELECT 1, 'be'
UNION ALL SELECT 1, 'ch'
UNION ALL SELECT 1, 'gk'
UNION ALL SELECT 2, 'hi'
UNION ALL SELECT 2, 'ky'
UNION ALL SELECT 2, 'ft'
UNION ALL SELECT 3 ,'bf'
UNION ALL SELECT 3, 'mu' SELECT * FROM
(SELECT DISTINCT id FROM @t) a
CROSS APPLY
(SELECT v=STUFF(
(SELECT ',' + v FROM @t WHERE id=a.id FOR XML PATH(''),TYPE).value('/','VARCHAR(1000)')
,1,1,'')
) b
SELECT *
FROM(
SELECT DISTINCT
id
FROM @t
)A
OUTER APPLY(
SELECT
[values]= STUFF(REPLACE(REPLACE(
(
SELECT value FROM @t N
WHERE id = A.id
FOR XML AUTO
), '<N value="', ','), '"/>', ''), 1, 1, '')
)N
(
id int,
value varchar(10)
)
insert into tt values(1, 'aa')
insert into tt values(1, 'bb')
insert into tt values(2, 'aaa')
insert into tt values(2, 'bbb')
insert into tt values(2, 'ccc')
go CREATE FUNCTION dbo.f_str(@id int)
RETURNS varchar(8000)
AS
BEGIN
DECLARE @r varchar(8000)
SET @r=''
SELECT @r=@r+','+value FROM tt WHERE id=@id
RETURN STUFF(@r,1,1,'') END
GO -- 调用函数
SELECt id,value=dbo.f_str(id) FROM tt GROUP BY id
原著:邹建
改编:爱新觉罗.毓华(十八年风雨,守得冰山雪莲花开) 2007-12-16 广东深圳表结构,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。)
--1. 创建处理函数
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')
goCREATE FUNCTION dbo.f_str(@id int)
RETURNS varchar(8000)
AS
BEGIN
DECLARE @r varchar(8000)
SET @r = ''
SELECT @r = @r + ',' + value FROM tb WHERE id=@id
RETURN STUFF(@r, 1, 1, '')
END
GO-- 调用函数
SELECt id, value = dbo.f_str(id) FROM tb GROUP BY iddrop table tb
drop function dbo.f_str/*
id value
----------- -----------
1 aa,bb
2 aaa,bbb,ccc
(所影响的行数为 2 行)
*/--2、另外一种函数.
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--创建一个合并的函数
create function f_hb(@id int)
returns varchar(8000)
as
begin
declare @str varchar(8000)
set @str = ''
select @str = @str + ',' + cast(value as varchar) from tb where id = @id
set @str = right(@str , len(@str) - 1)
return(@str)
End
go--调用自定义函数得到结果:
select distinct id ,dbo.f_hb(id) as value from tbdrop table tb
drop function dbo.f_hb/*
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')
goselect 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
INSERT INTO #A SELECT '001','A'
INSERT INTO #A SELECT '001','B'
INSERT INTO #A SELECT '001','C'
INSERT INTO #A SELECT '001','D'
INSERT INTO #A SELECT '002','AA'
INSERT INTO #A SELECT '002','AC'
INSERT INTO #A SELECT '003','SS'
INSERT INTO #A SELECT '003','AA'
INSERT INTO #A SELECT '003','GH'CREATE TABLE #TEMP (S_NO VARCHAR(50),S_NAME VARCHAR(50),S_TEXT VARCHAR(1000))
INSERT INTO #TEMP
SELECT S_NO,MIN(S_NAME),MIN(S_NAME)
FROM #A
GROUP BY S_NOWHILE (SELECT COUNT(*) FROM #TEMP)<(SELECT COUNT(*) FROM #A)
BEGIN
UPDATE #TEMP
SET S_TEXT=(S_TEXT+','+B.S_NAME)FROM #TEMP A
LEFT JOIN
(SELECT S_NO,MIN(S_NAME)S_NAME
FROM #A
WHERE S_NO+S_NAME NOT IN (SELECT S_NO+S_NAME FROM #TEMP)
GROUP BY S_NO)B ON A.S_NO=B.S_NO
WHERE ISNULL(B.S_NAME,'')<>''
AND ISNULL(S_TEXT,'')<>''INSERT #TEMP
SELECT S_NO,MIN(S_NAME)S_NAME,''
FROM #A
WHERE S_NO+S_NAME NOT IN (SELECT S_NO+S_NAME FROM #TEMP)
GROUP BY S_NOENDSELECT S_NO,S_TEXT FROM #TEMP WHERE ISNULL(S_TEXT,'')<>''DROP TABLE #TEMP
DROP TABLE #A