SQL Server中时间按天分组

例1：

select Min(VisitTime),count(*) as Num from online group by datediff(day,VisitTime,getdate())

例2：

select count(*),Min(PayTime) from LimitBidBills where PayTime>'2020-07-25' and Status='已确认'
group by datediff(day,PayTime,getdate())
order by Min(PayTime) asc

例3：

select count(*),Min(PayTime) from LimitBidBills join LimitBidMail on LimitBidBills.InfoID = LimitBidMail.InfoID where PayTime>'2020-06-20' and   PayTime<'2020-07-5' and Status='已确认'
group by datediff(day,PayTime,getdate())
order by Min(PayTime) asc