select b.course_id,c.course_name ,max(b.seeing_num) as max_num from ( select a.course_id ,sum(a.count_num) over(partition by a.course_id,date(a.dt) order by a.dt asc,a.count_num desc) as seeing_num from ( select user_id ,course_id ,in_datetime as dt ,1 as count_num from attend_tb union ALL select us...