#限制条件:SQL类别 tag = 'SQL',5级以上 level > 5,当天回答 day(release_time) = day(start_time) #分组条件:exam_id #计算:符合条件的作答人数合计 uv,平均分 round(avg(score),1) #排序:uv desc,avg_score ASC select exam_id, count(distinct uid) as uv,  ...