MySQL的“排名在排行榜” -Query

Question

您好世界各地的程序员，

我工作的一个项目中，用户可以为它做某些事情，并获得积分。为了简化这个问题，我们假设我们有两个表用户和分。

-- table user  -- table points 
+---------------+ +-----------------------------+ 
| id | name | | id | points | user_id | 
+---------------+ +-----------------------------+ 
| 1  Tim | | 1  5   1  | 
| 2  Tom | | 2  10   1  | 
| 3  Marc | | 3  5   1  | 
| 4  Tina | | 4  12   2  | 
| 5  Lutz | | 5  2   2  | 
+---------------+ | 6  7   1  | 
        | 7  40   3  | 
        | 8  100  1  | 
        +-----------------------------+ 

我们得到完整的高分列表我用下面的查询

SELECT u.*, SUM(p.points) AS sum_points 
FROM user u 
LEFT JOIN points p ON p.user_id = u.id 
GROUP BY u.id 
ORDER BY sum_points DESC 

导致细高分名单与第一所有用户持续

+------------------------------+ 
| id | name | sum_points | 
+------------------------------+ 
| 1  Tim  127   | 
| 3  Marc  40   | 
| 2  Tom  14   | 
| 4  Tina  0   | 
| 5  Lutz  0   | 
+------------------------------+ 

好吧回到问题本身。在单个用户的个人资料上，我想在高分列表中显示他的排名。

这可以通过使用单个查询来完成，只需显示例如Tom（id = 2）排名在第3位？

非常感谢:-)

Answer 1

的想法是要问， “有多少玩家级以上@this_user”：

select count(*) + 1 from 
(
    /* list of all users */ 
    SELECT SUM(p.points) AS sum_points 
    FROM user u 
    LEFT JOIN points p ON p.user_id = u.id 
    GROUP BY u.id   
) x 
/* just count the ones with higher sum_points */ 
where sum_points > (select sum(points) from points where user_id = @this_user) 

编辑做的结果，而不是基于1 0-based

Answer 2

SELECT q.*, 
     @r := @r + 1 AS rank 
FROM (
     SELECT @r := 0 
     ) vars, 
     (
     SELECT u.*, 
       SUM(p.points) AS sum_points 
     FROM 
       user u 
     LEFT JOIN 
       points p 
     ON  p.user_id = u.id 
     GROUP BY 
       u.id 
     ORDER BY 
       sum_points DESC 
     ) q