题解 | #异常的邮件概率#
异常的邮件概率
http://www.nowcoder.com/practice/d6dd656483b545159d3aa89b4c26004e
select nor.date,round(sum(nor.type='no_completed')/count(nor.date),3) p from ( select * from email where send_id not in (select id from user where is_blacklist=1) and receive_id not in (select id from user where is_blacklist=1) ) nor group by nor.date