题解 | 计算用户的平均次日留存率
计算用户的平均次日留存率
https://www.nowcoder.com/practice/126083961ae0415fbde061d7ebbde453
select round(count(date2)/count(date1),4) as avg_ret from ( select distinct b.device_Id, b.date as date1, a.date as date2 from question_practice_detail b left join (select distinct device_Id, date from question_practice_detail)a on b.device_id = a.device_id and datediff(b.date,a.date) = 1) c
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