SQL SERVER使用STUFF函数拼接记录为逗号分隔符
SQL SERVER使用STUFF函数拼接记录为逗号分隔符
要这种效果。
create table tb(idint, value varchar(10))
insert into tbvalues(1,'aa')
insert into tbvalues(1,'bb')
insert into tbvalues(2,'aaa')
insert into tbvalues(2,'bbb')
insert into tbvalues(2,'ccc')
/* stuff(param1, startIndex, length, param2)
说明:将param1中自startIndex(SQL中都是从1开始,而非0)起,删除length个字符,然后用param2替换删掉的字符。*/
SELECT id,
value = stuff((SELECT ',' + value
FROM tb AS t
WHERE t .id = tb.id FOR xml path('')), 1, 1, '')
FROM tb
GROUP BY id
这样即可。
例如 两个表 汽车分组表tb_group,和汽车表tb_car
select id, groupname, contace, mobile, begintime, endtime, parkingcount, groupType
,value = stuff((SELECT ',' + plate FROM tb_car AS t WHERE t .groupid = [tb_group].id FOR xml path('')), 1, 1, '')
from [dbo].[tb_group]
结果为
/*
标题:按某字段合并字符串之一(简单合并)
作者:(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')
create function dbo.f_str(@id varchar(10)) returns varchar(1000)
begin
declare @str varchar(1000)
select @str = isnull(@str + ',' , '') + cast(value as varchar) from tb where id = @id
return @str
--调用函数
select id , value = dbo.f_str(id) from tb group by id
drop 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')
select id, [value] = stuff((select ',' + [value] from tb t where id = tb.id for xml path('')) , 1 , 1 , '')
from tb
group by id
drop 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')
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)
begin
insert @t values(@id_old , stuff(@s,1,1,''))
select @s = ',' + cast(@value as varchar) , @id_old = @id
fetch my_cursor into @id , @value