题解 | #获得积分最多的人(二)#

这一道题就是接着上一道题的思路继续延伸。

主要是多了一步将lomit 0,1 所代表的最大值提取出来的过程。

select id, name, total_num
from 
    user
left outer join 
    (select user_id, sum(grade_num) as total_num
    from grade_info
    group by user_id
    order by total_num desc) as grade
on user.id = grade.user_id
group by user.id
having total_num = (select total_num 
                    from (select user_id, sum(grade_num) as total_num
                          from grade_info
                          group by user_id
                          order by total_num desc) as grade 
                    limit 0,1)
order by user.id;