SqlServer 得到指定日期时间段内的随机时间

----用视图辅助得到随机数

alter VIEW v_RAND
AS
SELECT re=RAND()
GO

--得到指定时间段的随机时间
alter function fn_getdate 
(
 @begin_date datetime,
 @end_date datetime
)
    returns varchar(100)
as
begin

declare @second varchar(50)
if @begin_date is null
 SET @begin_date='2009-09-17 08:01:01';
if @end_date is null
 SET @end_date='2009-10-14 17:30:00';
SET @second = DATEDIFF ( second , @begin_date,@end_date)

declare @d1 datetime
declare @rand float
select @rand=re from v_RAND
set @d1 = dateadd(second,@rand*@second,@begin_date)
if datepart(hour,@d1) >18
begin
  set @d1=dateadd(hour,-8,@d1)
end
if datepart(hour,@d1) <8
begin
  set @d1=dateadd(hour,8,@d1)    
end
    return @d1
     
end
go

 --测试

select dbo.fn_getdate(null,null)

 
--结果
----------------------------------------------------------------------------------------------------
10 12 2009  9:23AM

（所影响的行数为 1 行）