qq_27527961的博客

求登录时长 ### DATEDIFF(d,LoginTime,getdate()) as diffDate , 计算登录次数，登录时间为顺序来计算rownumber ### ROW_NUMBER() over(partition by Name order by LoginTime desc) as rn 合并起来 select top 1 Name,diffRn,COUNT(diffRn)as LoginCount from( select Name,diffDat.