题解 | #分别满足两个活动的人#
分别满足两个活动的人
https://www.nowcoder.com/practice/a126cea91d7045e399b8ecdcadfb326f
select uid,'activity1' as activity from exam_record,examination_info where exam_record.exam_id=examination_info.exam_id and year(submit_time)=2021 group by uid having min(score) >=85 union all select uid,'activity2' as activity from exam_record,examination_info where exam_record.exam_id=examination_info.exam_id and year(submit_time)=2021 and score >80 and difficulty = 'hard' and timestampdiff(second,start_time,submit_time) * 2 <= duration * 60 order by uid
使用timestampdiff可以将时间计算结果转换为秒,方便比较
一开始思路想用timediff,但是不好比较,timestampdiff比较方便。