时间比较操作

昨天
select count(*) from orders where convert(varchar(10),addtime,120)=(select cast(datepart(year,getdate()) as varchar)+'-'+cast(datepart(month,getdate()) as varchar)+'-'+cast(datepart(day,getdate()-1) as varchar))
今天
select count(*) from orders where convert(varchar(10),addtime,120)=(select cast(datepart(year,getdate()) as varchar)+'-'+cast(datepart(month,getdate()) as varchar)+'-'+cast(datepart(day,getdate()) as varchar))