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
# 先找>=85
select uid,'activity1' activity from exam_record
where year(submit_time)=2021
group by uid
having min(score) >=85
union all
# 找到一半时间完成高难度且得分>80
select distinct uid,'activity2' activity
from exam_record join examination_info using(exam_id)
where difficulty='hard' and year(submit_time)=2021 and score>80
and timestampdiff(second,start_time,submit_time)<=(duration/2*60)
order by uid
# timestampdiff(second，用秒才准确，好像。
