这个写法确实是错的，应该在WHERE先筛选出符合的uid，然后在求MAX的时候不能筛成tag = '算法' 。 答案：SELECT ui.uid, level, register_time, MAX(score) max_score FROM user_info as ui INNER JOIN exam_record as er ON ui.uid = er.uid INNER JOIN examination_info as ei ON ei.exam_id = er.exam_id WHERE job = '算法' AND DATE(register_time) = DATE(submit_time) AND ui.uid in ( SELECT DISTINCT ui.uid FROM user_info as ui INNER JOIN exam_record as er ON ui.uid = er.uid INNER JOIN examination_info as ei ON ei.exam_id = er.exam_id WHERE job = '算法' and tag = '算法' AND DATE(register_time) = DATE(submit_time) ) GROUP BY ui.uid ORDER BY max_score DESC LIMIT 3 OFFSET 6