sql: 生日三个月内有效

DECLARE @birthday  datetime,@stat datetime,@end datetime,@statbirthday datetime,@endbirthday datetime,@thirdbirthday datetime,@firthbirthday datetime, @year int,@month int , @day int,@str varchar(20),@total int,@firthmonth int,@thirmonth int,@now  datetime,@vipno nvarchar(10) --参数
set @vipno='8888888'
set @now='2014-01-25'
set @year=Year(@now)
select  @birthday=birthday from vip1 where vipno=@vipno
set @month=month(@birthday)
set @day=day(@birthday)
set @str=cast(@year as varchar(4))+'-'+cast(@month as varchar(2))+'-'+cast(@day as varchar(2))
set @birthday=cast(@str as datetime)
--會員生日有效生首日起至3個月內有效
set @firthbirthday=DATEADD(mm, DATEDIFF(mm,0,@birthday)-2, 0)--DATEADD(mm, DATEDIFF(mm,0,@birthday), 0)  --当月的第一天
--set @thirdbirthday=DATEADD(ms,-3,DATEADD(mm, DATEDIFF(m,0,getdate())+3, 0)) --后三个月最后的一天
SELECT @firthbirthday=DATEADD(MONTH,-2,DATEADD(MONTH,DATEDIFF(MONTH,0,@birthday),0))
--select cast(@firthbirthday as datetime)
--set @firthbirthday=DATEADD(MONTH,-2,DATEADD(MONTH,DATEDIFF(MONTH,0,@birthday),0))--DATEADD(Month,0,CONVERT(datetime,CONVERT(char(8),getdate(),120)+'1'))
--select @firthbirthday
--DATEADD(mm,0, DATEDIFF(mm,0,@birthday), 0)  --前三个月的第一天
--set @firthbirthday=convert(datetime, @thirdbirthday)
--SELECT  三個月有效 塗聚文 涂聚文
set @firthmonth=month(@now)-2
set @thirmonth=month(@now)
set @thirdbirthday=DATEADD(ms,-3,DATEADD(mm, DATEDIFF(mm,0,@now)+1, 0)) --当月最后的一天
set @thirdbirthday=cast(@thirdbirthday as datetime)
set @statbirthday=DATEADD(mm, DATEDIFF(mm,0,@birthday)-13, 0)
set @endbirthday=DATEADD(ms,-3,DATEADD(mm, DATEDIFF(mm,0,@birthday)-1, 0))
--select @statbirthday,@endbirthday,@firthbirthday,@thirdbirthday,@birthday,@firthmonth,@thirmonth
--以月份來吧
SELECT  *  FROM View_birthdayVipdlyList WHERE DATEDIFF(month,NowBirthday,@now)>=0 and  DATEDIFF(month,NowBirthday,@now)<=2  and vipno=@vipno order by VipBirthdayDate desc

--SELECT  *  FROM vip1 WHERE indate>@statbirthday AND  indate<@endbirthday and  month(birthday)>=@firthmonth and month(birthday)<=@thirmonth --and vipno=@vipno

--SELECT @total=ISNULL(SUM(amount),0) FROM View_birthdayVipdlyList WHERE indate>@statbirthday AND  indate<@endbirthday and  month(birthday)>=@firthmonth and month(birthday)<=@thirmonth and vipno=@vipno
--SELECT @total=@total*.01 



SELECT  count(*) as 'total'  FROM View_birthdayVipdlyList WHERE DATEDIFF(month,NowBirthday,getdate())>=0 and  DATEDIFF(month,NowBirthday,getdate())<=2  and vipno=@vipno


if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[GetVipNowBirthday]') and xtype in (N'FN', N'IF', N'TF'))
drop function [dbo].[GetVipNowBirthday]
GO
CREATE   function  GetVipNowBirthday
(  
   @vipno nvarchar(10), --参数
   @now datetime
)
returns datetime
AS
begin
declare @NowBirthday datetime, @birthday  datetime,@stat datetime,@end datetime,@statbirthday datetime,@endbirthday datetime,@thirdbirthday datetime,@firthbirthday datetime, @year int,@month int , @day int,@str varchar(40),@total decimal

select @birthday=birthday from vip1 where vipno=@vipno and birthday is not null
set @year=Year(@now)
if month(@now)=1 and month(@birthday)=12
begin
   set @year=@year-1
end
if month(@now)=1 and month(@birthday)=11
begin
   set @year=@year-1
end
if month(@now)=2 and month(@birthday)=12 
begin
   set @year=@year-1
end
set @month=month(@birthday)
set @day=day(@birthday)
set @str=cast(@year as varchar(4))+'-'+cast(@month as varchar(2))+'-'+cast(@day as varchar(2))
set @NowBirthday=convert(datetime,@str) ---cast(@str as datetime)
return @NowBirthday
end
GO

select top 100  vipno,birthday,[dbo].[GetVipNowBirthday](vipno,'2014-03-23') as 'now' from dbo.vip1 where month(birthday)=12 or month(birthday)=11