我怎样得出1-24小时的数据

select t1.h 小时 , isnull(t2.数量,0) 数量 from

        (select 1 as h union select 2 union select 3 union select 4 union select 5

        union select 6 union select 7 union select 8 union select 9

        union select 10 union select 11 union select 12 union select 13

        union select 14 union select 15 union select 16 union select 17

        union select 18 union select 19 union select 20 union select 21

        union select 22 union select 23 union select 24) t1

left join

(

  SELECT h = DATEPART(hh,register_time),数量 = count(register_time)   

  from [RegisterInfo]   

  group by DATEPART(hh,register_time) 

) t2

on t1.h = t2.h

select top 24 identity(int,0,1) as N into # from sysobjects a,sysobjects b



select b.n,sum(a.数量) as 数量

from # b

left join tabea a

on b.n = datepart(hh,datecole)

group by b.n





drop table #

declare @a table(id int identity(0,1),a int)

insert @a select top 24 0 from syscolumns



declare @b table(a datetime)

insert @b select '2007-12-10 05:20:13.000' 

union all select '2007-11-21 08:20:40.000' 

union all select '2007-12-03 04:21:31.000' 

union all select '2007-11-04 10:21:04.000' 



select id,isnull(x,0) num from @a a

left join

(select datepart(hour,a)a,count(1) x from @b group by datepart(hour,a))b

on a.id=b.a





--result

/*

id          num         

----------- ----------- 

0           0

1           0

2           0

3           0

4           1

5           1

6           0

7           0

8           1

9           0

10          1

11          0

12          0

13          0

14          0

15          0

16          0

17          0

18          0

19          0

20          0

21          0

22          0

23          0



（所影响的行数为 24 行）



*/