有一个表,有2个字段name和res
现在的结构是:
name res
Terry welcome
Terry to
Terry China
Alice how
Alice are
Alice you?
....
想要的结果是:
name res
Terry welcome to China
Alice how are you?
....
请问有什么办法?谢谢
现在的结构是:
name res
Terry welcome
Terry to
Terry China
Alice how
Alice are
Alice you?
....
想要的结果是:
name res
Terry welcome to China
Alice how are you?
....
请问有什么办法?谢谢
RETURNS VARCHAR(50)
AS
BEGIN
DECLARE @CLASS VARCHAR(50)
SELECT @CLASS=ISNULL(@CLASS+',','')+课程名 FROM tB WHERE 学号=@学号
RETURN @CLASS
END自己更改下
--> 测试数据:[TB]
if object_id('[TB]') is not null drop table [TB]
go
create table [TB]([name] varchar(5),[res] varchar(7))
insert [TB]
select 'Terry','welcome' union all
select 'Terry','to' union all
select 'Terry','China' union all
select 'Alice','how' union all
select 'Alice','are' union all
select 'Alice','you?'
--------------开始查询--------------------------ALTER FUNCTION GET_STRING(@name VARCHAR(50))
RETURNS VARCHAR(50)
AS
BEGIN
DECLARE @CLASS VARCHAR(50)
SELECT @CLASS=ISNULL(@CLASS+' ','')+res FROM tB WHERE name=@name
RETURN @CLASS
ENDselect NAME,DBO.GET_STRING(NAME)AS res from [TB] GROUP BY NAME
----------------结果----------------------------
/*
NAME res
----- --------------------------------------------------
Alice how are you?
Terry welcome to China(所影响的行数为 2 行)
*/
create table tb(name varchar(10), res varchar(10))
insert into tb values('Terry', 'welcome')
insert into tb values('Terry', 'to')
insert into tb values('Terry', 'China')
insert into tb values('Alice', 'how')
insert into tb values('Alice', 'are')
insert into tb values('Alice', 'you?')
gocreate function dbo.f_str(@name varchar(10)) returns varchar(100)
as
begin
declare @str varchar(1000)
set @str = ''
select @str = @str + ' ' + cast(res as varchar) from tb where name = @name
set @str = right(@str , len(@str) - 1)
return @str
end
go--调用函数
select name , res = dbo.f_str(name) from tb group by namedrop function dbo.f_str
drop table tb/*
name res
---------- -----------------
Alice how are you?
Terry welcome to China(所影响的行数为 2 行)
*//*
标题:按某字段合并字符串之一(简单合并)
作者:爱新觉罗.毓华(十八年风雨,守得冰山雪莲花开)
时间:2008-11-06
地点:广东深圳描述:将如下形式的数据按id字段合并value字段。
id value
----- ------
1 aa
1 bb
2 aaa
2 bbb
2 ccc
需要得到结果:
id value
------ -----------
1 aa,bb
2 aaa,bbb,ccc
即:group by id, 求 value 的和(字符串相加)
*/
--1、sql2000中只能用自定义的函数解决
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')
gocreate function dbo.f_str(@id int) returns varchar(100)
as
begin
declare @str varchar(1000)
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--调用函数
select id , value = dbo.f_str(id) from tb group by iddrop function dbo.f_str
drop table tb
--2、sql2005中的方法
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, [value] = stuff((select ',' + [value] from tb t where id = tb.id for xml path('')) , 1 , 1 , '')
from tb
group by iddrop table tb
--3、使用游标合并数据
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
declare @t table(id int,value varchar(100))--定义结果集表变量
--定义游标并进行合并处理
declare my_cursor cursor local for
select id , value from tb
declare @id_old int , @id int , @value varchar(10) , @s varchar(100)
open my_cursor
fetch my_cursor into @id , @value
select @id_old = @id , @s=''
while @@FETCH_STATUS = 0
begin
if @id = @id_old
select @s = @s + ',' + cast(@value as varchar)
else
begin
insert @t values(@id_old , stuff(@s,1,1,''))
select @s = ',' + cast(@value as varchar) , @id_old = @id
end
fetch my_cursor into @id , @value
END
insert @t values(@id_old , stuff(@s,1,1,''))
close my_cursor
deallocate my_cursorselect * from @t
drop table tb
--*******************************************************************************************
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