在查询中查询相同记录的合并

[dxinyan]

定义的合并函数:
create function dbo.f_str(@RQ Datetime,@code nvarchar(50)) returns nvarchar(1000)
as
begin
declare @str varchar(1000)
select @str = isnull(@str + ',' , '') + cast(j_mark as nvarchar) from Tb_perday1002 where RQ = @RQ and code=@code
return @str
end
go

查询语句如下 :
select PP.RQ,PP.code,PP.sm,PP.j_mark=dbo.f_str(PP.RQ,PP.a) from
(select RQ ,code,sum(perday) as sm,j_mark
from Tb_perday1002 T
group by T.RQ,T.code,T.j_mark) as PP
group by PP.RQ,PP.code

运行后出现提示:
消息 170，级别 15，状态 1，第 1 行
第 1 行: '=' 附近有语法错误。
消息 156，级别 15，状态 1，第 3 行
在关键字 'as' 附近有语法错误。

在查询中使用f_str 合并函数,不可以吗?

[dawugui]

/*
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')
go

create function dbo.f_str(@id varchar(10)) returns varchar(1000)
as
begin
  declare @str varchar(1000)
  select @str = isnull(@str + ',' , '') + cast(value as varchar) from tb where id = @id
  return @str
end
go

--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')
go

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')
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_cursor

select * from @t
drop table tb

[--小F--]

--是你那里的逗号有问题吧
select
 PP.RQ,PP.code,PP.sm,PP.j_mark=dbo.f_str(PP.RQ,PP.a) 
from
(select RQ ,code,sum(perday) as sm,j_mark  from Tb_perday1002 T group by T.RQ,T.code,T.j_mark) as PP
group by
 PP.RQ,PP.code

[快溜]

create function dbo.f_str(@RQ Datetime,@code nvarchar(50)) returns nvarchar(1000)
as
begin
  declare @str varchar(1000)
  select @str = isnull(@str,'') + ',' + cast(j_mark as nvarchar) from Tb_perday1002 where RQ = @RQ and code=@code
  return @str
end
go

[dxinyan]

谢谢,知道了,原来在函数中使用查询

[Shawn]

select 
	PP.RQ,
	PP.code,
	PP.sm, --PP.sm列没在group中,会报错
	j_mark=dbo.f_str(PP.RQ,PP.a) --别名不能用PP.j_mark; PP.a列没在group中,会报错
from
(
	select 
		RQ ,
		code,
		sum(perday) as sm,
		j_mark  
	from Tb_perday1002 T
	group by 
		T.RQ,
		T.code,
		T.j_mark
) as PP
group by  --自己理解一下GROUP BY的含义
	PP.RQ,
	PP.code