帮我看一下这个sql语句如何写

有一个表#t1，数据如下：
SQL code

f1      f2     f3      f4    f5    f6
A001    A      -1      1     0     0 
A002    B              1     0     -1

表#t2的数据如下：
SQL code

f1      f2     f3      f4    f5    f6
A001    A       0      0     12    0
A002    B       0      0     14    0
A003    C       0      0     -8    0
A003    C       0      0     10    0 

我想把#t2的数据合并到#t1里去，只要是#t2.f1=#t1.f1 and #t2.f2=#t1.f2，只是把#t2.f5的数据合并到#t1的f5里去，结果是：
SQL code

f1      f2     f3      f4    f5     f6
A001    A      -1       1     12    0
A002    B               1     14    -1
A003    C      0        0      2    0

这个sql语句如何来写？

SQL code

select f1,f2,sum(f3) f3,sum(f4) f4,sum(f5) f5
from(
    select * from #t1
    union all
    select * from #t2
)t
group by f1,f2

发两遍了吧

--存在的，更新。
update t1 set f5 = f5 + isnull((select sum(f5) from t2 where t2.f1 = t1.f1 and t2.f2 = t1.f2),0)

--不存在，怎么办？

相同貼發一貼就行了


SQL code

use Tempdb
go
--> --> 
 
if not object_id(N'Tempdb..#T') is null
    drop table #T
Go
Create table #T([f1] nvarchar(4),[f2] nvarchar(1),[f3] int,[f4] int,[f5] int,[f6] int)
Insert #T
select N'A001',N'A',-1,1,0,0 union all
select N'A002',N'B',NULL,1,0,-1
Go

--> --> 
 
if not object_id(N'Tempdb..#T2') is null
    drop table #T2
Go
Create table #T2([f1] nvarchar(4),[f2] nvarchar(1),[f3] int,[f4] int,[f5] int,[f6] int)
Insert #T2
select N'A001',N'A',0,0,12,0 union all
select N'A002',N'B',0,0,14,0 union all
select N'A003',N'C',0,0,-8,0 union all
select N'A003',N'C',0,0,10,0
Go

SELECT 

f1 , f2,f3=MAX(f3),f4=MAX(f4),f5=SUM(f5),f6=min(f6)
FROM 
(SELECT * FROM #T
UNION all
Select * from #T2
)t
GROUP BY 
f1, f2

/*
f1   f2   f3          f4          f5          f6
---- ---- ----------- ----------- ----------- -----------
A001 A    0           1           12          0
A002 B    0           1           14          -1
A003 C    0           0           2           0
*/

不知道怎么大家都喜欢把帖子发两遍？

SQL code

更新

use Tempdb
go
--> --> 
 
if not object_id(N'Tempdb..#T') is null
    drop table #T
Go
Create table #T([f1] nvarchar(4),[f2] nvarchar(1),[f3] int,[f4] int,[f5] int,[f6] int)
Insert #T
select N'A001',N'A',-1,1,0,0 union all
select N'A002',N'B',NULL,1,0,-1
Go

--> --> 
 
if not object_id(N'Tempdb..#T2') is null
    drop table #T2
Go
Create table #T2([f1] nvarchar(4),[f2] nvarchar(1),[f3] int,[f4] int,[f5] int,[f6] int)
Insert #T2
select N'A001',N'A',0,0,12,0 union all
select N'A002',N'B',0,0,14,0 union all
select N'A003',N'C',0,0,-8,0 union all
select N'A003',N'C',0,0,10,0
Go

UPDATE b
SET f5=a.[f5]+b.f5
FROM (Select f1,f2,SUM(f5) AS f5 from #T2 GROUP BY f1,f2) a  INNER JOIN #T AS b ON a.[f1]=b.[f1] AND a.[f2]=b.[f2]

INSERT INTO #T
        ( f1, f2, f3, f4, f5, f6 )
Select f1,f2,MAX([f3]),MAX([f4]),SUM(f5) AS f5 ,MIN([f6])
from #T2  AS a
WHERE NOT EXISTS(SELECT 1 FROM #T WHERE f1=a.f1 AND f2=a.f2)
GROUP BY f1,f2

SELECT * FROM #T
/*
f1    f2    f3    f4    f5    f6
A001    A    -1    1    12    0
A002    B    NULL    1    14    -1
A003    C    0    0    2    0
*/

#4楼不对，不能用max()和min()的，因为f3/f4/f6字段的数据有些是正数、负数、字符都有的，如果用max()或min()就会过滤掉，反正我不管f3/f4/f6字段里有什么数据，只要#t1.f1=#t2.f1和#t1.f2=#t2.f2，就把#t2.f5的数据合并到#t1.f5里去

SQL code

/*
f1                                                 f2         f3          f4          f5          f6
-------------------------------------------------- ---------- ----------- ----------- ----------- -----------
A001                                               A          -1          1           12          0
A002                                               B          NULL        1           14          -1
*/
 update t1 set f5= (select SUM(f5)   as f5  from t2 where t1.f1= f1 group by f1,f2)  

这样不可以吗？同样的贴我把上次的COPY过来了。

select f1,f2,sum(f3) f3,sum(f4) f4,sum(f5) f5
from(
  select * from #t1
  union all
  select * from #t2
)t
group by f1,f2

看看是不是5樓這個意思