这道题我真的服了,纯小白直接上手撕sql题来学sql,看了评论区给我绕了两个小时。我本人是不太习惯这种全部步骤都写在select里的,很容易绕晕,然后问gpt后发现可以用with as虚拟一个表然后再用left join来写=_= WITH base AS ( SELECT DISTINCT device_id, date FROM question_practice_detail),next_day AS ( SELECT DISTINCT device_id, DATE_ADD(date, INTERVAL 1 DAY) AS date FROM question_practice_d...