1.内连接+dense_rank() over(...)窗口函数select id,name,scorefrom (select t1.*,t2.name,dense_rank() over(partition by t1.language_id order by t1.score desc) rkfrom grade t1 join language t2 on t1.language_id=t2.id ) twhere rk in (1,2)order by name asc,score desc,id asc; 2.关联子查询select t1.id,t2.name,scorefrom ...