题解 | #异常的邮件概率#
异常的邮件概率
https://www.nowcoder.com/practice/d6dd656483b545159d3aa89b4c26004e
select date, round(sum(type = "no_completed") / count(email.id), 3)as p from email where send_id not in (select u.id from user u where is_blacklist = 1) and receive_id not in (select u.id from user u where is_blacklist = 1) group by date
