题解 | #牛客每个人最近的登录日期(二)#
牛客每个人最近的登录日期(二)
http://www.nowcoder.com/practice/7cc3c814329546e89e71bb45c805c9ad
with shebei as ( select user_id,name,date from login a left join client b on a.client_id=b.id where date in( select max(date) from login group by user_id ) ), t2 as ( select b.name as u_n,a.name as c_n,max(date) as date from shebei a left join user b on a.user_id=b.id group by b.name,a.name order by b.name ) select u_n,c_n,max(date) as date from t2 group by u_n order by u_n
标题
先找出所有用户对应的登陆日期,登录设备编号和登录设备名称
然后再从以上信息中找到不同设备最近一次登录的日期、设备
最后再从最近一次登录的信息中找出在所有设备情况下最近一次登录的信息