合并列值
原著:邹建
改编:爱新觉罗.毓华 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)
*/
原著:邹建
改编:爱新觉罗.毓华 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)
*/
create table Table1(ID varchar(10) , carID varchar(10), Start varchar(10), [End] varchar(10) )
insert into table1 values('C001', '京A11111', '北京', '上海')
insert into table1 values('C002', '沪A11111', '上海', '西安')
create table Table2(ID varchar(10), Pass varchar(10))
insert into table2 values('C001', '天津')
insert into table2 values('C001', '石家庄')
insert into table2 values('C001', '南京')
insert into table2 values('C001', '苏州')
insert into table2 values('C002', '苏州')
insert into table2 values('C002', '郑州')
insert into table2 values('C002', '太原')
go--创建一个合并的函数
create function f_hb(@id varchar(10))
returns varchar(8000)
as
begin
declare @str varchar(8000)
set @str = ''
select @str = @str + ',' + cast(pass as varchar) from table2 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 m.ID,m.carID,m.Start,n.Pass,m.[End] from table1 m,
(select distinct id ,dbo.f_hb(id) as pass from table2) n
where m.id = n.iddrop function dbo.f_hb
drop table table1,table2/*
ID carID Start Pass End
---------- ---------- ---------- -------------------- -------
C001 京A11111 北京 天津,石家庄,南京,苏州 上海
C002 沪A11111 上海 苏州,郑州,太原 西安(所影响的行数为 2 行)
*/
create table Table1(ID varchar(10) , carID varchar(10), Start varchar(10), [End] varchar(10) )
insert into table1 values('C001', '京A11111', '北京', '上海')
insert into table1 values('C002', '沪A11111', '上海', '西安')
create table Table2(ID varchar(10), Pass varchar(10))
insert into table2 values('C001', '天津')
insert into table2 values('C001', '石家庄')
insert into table2 values('C001', '南京')
insert into table2 values('C001', '苏州')
insert into table2 values('C002', '苏州')
insert into table2 values('C002', '郑州')
insert into table2 values('C002', '太原')
goselect t1.ID,t1.carID,t1.Start,t2.Pass,t1.[End] from table1 t1,
(SELECT * FROM(SELECT DISTINCT id FROM table2)A OUTER APPLY(
SELECT [Pass]= STUFF(REPLACE(REPLACE(
(
SELECT Pass FROM table2 N
WHERE id = A.id
FOR XML AUTO
), '<N Pass="', ','), '"/>', ''), 1, 1, '')
)N) t2
where t1.id = t2.iddrop table table1,table2/*
ID carID Start Pass End
---------- ---------- ---------- -------------------- -------
C001 京A11111 北京 天津,石家庄,南京,苏州 上海
C002 沪A11111 上海 苏州,郑州,太原 西安(2 行受影响)
*/
CREATE TABLE Table1(ID varchar(10),carID varchar(20),Start varchar(20),[End] varchar(20))
insert into Table1 values('C001', '京A11111', '北京', '上海')
insert into Table1 values('C002', '沪A11111', '上海', '西安')
go
CREATE TABLE Table2(ID varchar(10),Pass varchar(10))
insert into Table2 values('C001', '天津')
insert into Table2 values('C001', '石家庄')
insert into Table2 values('C001', '南京')
insert into Table2 values('C001', '苏州')
insert into Table2 values('C002', '苏州')
insert into Table2 values('C002', '郑州')
insert into Table2 values('C002', '太原')
go
create function f_form_string
(
@ID varchar(10)
)
returns varchar(8000)
as
begin
declare @sql varchar(8000)
set @sql = ''
select @sql = @sql + ',' + Pass from table2 where ID = @ID
select @sql = substring(@sql,2,8000)
return @sql
end
goselect ID,carID,Start,dbo.f_form_string(ID)as Pass,[End] from Table1--drop table table1
--drop table table2
--drop function f_form_string
---定义一个函数
CREATE FUNCTION dbo.StrLink(@id varchar(50))
RETURNS VARCHAR(8000)
AS
BEGIN
DECLARE @ColStr VARCHAR(8000)
SET @ColStr=''
SELECT @ColStr=@ColStr+','+FieldName FROM table2 WHERE [id]=@id
IF LEN(@ColStr)>0
BEGIN
SET @ColStr=RIGHT(@ColStr,LEN(@ColStr)-1)
END
RETURN @ColStr
END
GOselect t1.ID,t1.carID,t1.Start,t2.Pass,t1.[End] from table1 t1 inner join
(select id ,dbo.StrLink(id) as pass from table2 group by id )t2ON t1.id=t2.id