题解 | #筛选限定昵称成就值活跃日期的用户#

select uid, nick_name, achievement
from user_info
where nick_name LIKE '牛客%号'
and achievement BETWEEN 1200 and 2500
and uid in (select er.uid
            from exam_record as er
            left join practice_record as pr on er.uid = pr.uid
#             错误：
#             where (max(year(start_time)) = 2021 and max(month(start_time)) = 9)
#             or (max(year(pr.submit_time)) = 2021 and max(month(pr.submit_time)) = 9)
            group by er.uid
            having (max(year(start_time)) = 2021 and max(month(start_time)) = 9)
            or (max(year(pr.submit_time)) = 2021 and max(month(pr.submit_time)) = 9)
           );