SQL中如何查询当天的数据。

Question

想查询一天添加了多少条数据。如 table1id  name  addtime其中，addtime 的格式为 2007-09-28 14:38:23.890

Answer 1

select count(1) from tb where datediff(dd,addtime,getdate())=0

Answer 2

select convert(varchar(10),addtime,120),count(*)
from tb
group by convert(varchar(10),addtime,120)

Answer 3

select
 convert(varchar(10),addtime,120),count(1)
from
 tb
group by
 convert(varchar(10),addtime,120)

Answer 4

select
 convert(varchar(10),addtime,120),count(1)
from
 tb
where
 datediff(dd,addtime,getdate())>=0
group by
 convert(varchar(10),addtime,120)

Answer 5

select count(1) from tb where datediff(dd,addtime,getdate())=0和select
 convert(varchar(10),addtime,120),count(1)
from
 tb
where
 datediff(dd,addtime,getdate())>=0
group by
 convert(varchar(10),addtime,120)
区别是？？