题解 | #筛选限定昵称成就值活跃日期的用户#

select uid,nick_name,achievement from (select uid,date_format(start_time,'%y%m') as month_start,'exam' as tag from exam_record where year(start_time)=2021 union all select uid,date_format(submit_time,'%y%m')as month_start,'practice' as tag from practice_record) as exam_practice left join user_info using(uid)

where (nick_name like '牛客%' and nick_name like '%号') and achievement BETWEEN 1200 and 2500 and month_start='2109' group by uid;