题解 | #平均活跃天数和月活人数#
平均活跃天数和月活人数
https://www.nowcoder.com/practice/9e2fb674b58b4f60ac765b7a37dde1b9
select date_format(submit_time,"%Y%m") as `month`, round(count(distinct uid,date(submit_time))/count(distinct uid),2) avg_active_days, #count计数时与distinct联合使用可以对多个值进行去重统计 count(distinct uid) mau from exam_record where year(submit_time) = 2021 and submit_time is not null group by `month`;
查看23道真题和解析
