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 CONCAT(uid,DATE_FORMAT(submit_time,'%Y%m%d')))/count( DISTINCT uid ),2) AS avg_active_days, count( DISTINCT uid ) AS mau FROM exam_record a WHERE YEAR ( submit_time )= 2021 GROUP BY date_format( submit_time, '%Y%m' )