declare @begin_date datetime,@end_time datetime 
select @begin_date='2012-04-11',@end_time='2012-04-13'
--1
select dateadd(dd,number,@begin_date) from master..spt_values where type='p' and number between 0 and datediff(dd,@begin_date,@end_time)
--2每月第2天
select dateadd(mm,number,convert(varchar(8),dateadd(mm,1,@begin_date),120)+'02') from master..spt_values where type='p' and number between 0 and datediff(dd,@begin_date,@end_time)
--3当按周重复时,周几就放(这个周几可以是复数)
select dateadd(ww,number,@begin_date) from master..spt_values where type='p' and number between 0 and datediff(dd,@begin_date,@end_time)
--每周的前三天
select dateadd(dd,number,dateadd(dd,9-datepart(dw,@begin_date),@begin_date)) from master..spt_values where type='p' and number between 0 and datediff(dd,@begin_date,@end_time)

------解决方案--------------------

SQL code

--1.当按时间段播放时,从几月几号到几月几号  
--根据2012-4-11到2012-4-13日,生成以下格式的记录.

declare @bd date,@ed date
select @bd='2012-4-11',@ed='2012-4-13'

select '1' as '文件ID', 
       'X' as '播放类型',
       dateadd(d,number,@bd) as '播放日期'
from master.dbo.spt_values 
where type='P' and number<=datediff(d,@bd,@ed)


文件ID 播放类型 播放日期
---- ---- ----------
 1     X    2012-04-11
 1     X    2012-04-12
 1     X    2012-04-13

(3 row(s) affected)


--2.当按天复复时,每隔几天播放.
--根据按每月第2天,生成以下记录

declare @x int
select @x=2

select '2' as '文件ID', 
       'Y' as '播放类型',
       cast(dateadd(d,number,'2012-01-01') as date) as '播放日期'
from master.dbo.spt_values 
where type='P' and number<=365
and day(dateadd(d,number,'2012-01-01'))=@x
and month(dateadd(d,number,'2012-01-01')) in (5,6,7)


文件ID 播放类型 播放日期
---- ---- ----------
 2     Y    2012-05-02
 2     Y    2012-06-02
 2     Y    2012-07-02

(3 row(s) affected)


--3.当按周重复时,周几就放(这个周几可以是复数)
--根据按每周第1,2,3,天,生成以下记录  

select '3' as '文件ID', 
       'N' as '播放类型',
       cast(dateadd(d,number,'2012-04-15') as date) as '播放日期'
from master.dbo.spt_values 
where type='P' and 
dateadd(d,number,'2012-04-15') between '2012-04-15' and '2012-04-21'
and datepart(dw,dateadd(d,number,'2012-04-15')) in (2,3,4)


文件ID 播放类型 播放日期
---- ---- ----------
 3     N    2012-04-16
 3     N    2012-04-17
 3     N    2012-04-18

(3 row(s) affected)


--4.按月重复,每月的第几天放.
--根据按每周第3天,生成以下记录

declare @x int
select @x=3

select '4' as '文件ID', 
       'N' as '播放类型',
       cast(dateadd(d,number,'2012-04-01') as date) as '播放日期'
from master.dbo.spt_values 
where type='P' and 
dateadd(d,number,'2012-04-01') between '2012-04-01' and '2012-04-30'
and datepart(dw,dateadd(d,number,'2012-04-15'))=@x


文件ID 播放类型 播放日期
---- ---- ----------
 4     N    2012-04-03
 4     N    2012-04-10
 4     N    2012-04-17
 4     N    2012-04-24

(4 row(s) affected)