declare @DSF table (id int,Dtime datetime,VAL numeric(3,2))
insert into @DSF
select 1,'2012-1-2',2.06 union all
select 2,'2012-1-2',3.00 union all
select 3,'2012-1-31',1.00

select b.number,sum(isnull(a.VAL,0)) as VAL 
from @DSF a right join master..spt_values b on day(a.Dtime)=b.number
where b.type='p' and b.number between 1 and 31 group by b.number
/*
number      VAL
----------- ---------------------------------------
1           0.00
2           5.06
3           0.00
4           0.00
5           0.00
6           0.00
7           0.00
8           0.00
9           0.00
10          0.00
11          0.00
12          0.00
13          0.00
14          0.00
15          0.00
16          0.00
17          0.00
18          0.00
19          0.00
20          0.00
21          0.00
22          0.00
23          0.00
24          0.00
25          0.00
26          0.00
27          0.00
28          0.00
29          0.00
30          0.00
31          1.00

(31 row(s) affected)
*/

------解决方案--------------------
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引用:
SQL code

declare @DSF table (id int,Dtime datetime,VAL numeric(3,2))
insert into @DSF
select 1,'2012-1-2',2.06 union all
select 2,'2012-1-2',3.00 union all
select 3,'2012……