如何在 php mysql 中制作排名系统？

Question

我有一个 php 应用程序，它有锻炼表，我在其中存储基于活动的日常用户锻炼数据（例如：跑步、步行、骑自行车）。在月底，我必须创建一个排行榜，以根据最高锻炼点生成排名。

SELECT total_distance, user_id,date_created 
   FROM workouts 
   WHERE date_created LIKE '%2019-11%' AND activity_type='Run'. 

通过上述查询，我​​得到如下所述的输出

我已经通过在查询中使用 GROUP BY user_id 优化了查询。

SELECT SUM(total_distance) as points, user_id,date_created 
    FROM workouts 
    WHERE date_created LIKE '%2019-11%' AND activity_type='Run' 
    GROUP BY user_id

我希望我的最终输出如第二张图片所示以及作为新列的排名。 如何为此编写查询。我做不到..

Answer 1

   SELECT 
   CASE WHEN @l=points THEN @rank ELSE @rank:=@rank+1 END as rank,@l:=points ,points,user_id from (select 
   SUM(total_distance) as points, user_id,date_created 
    FROM workouts 
    WHERE date_created LIKE '%2019-07%'  
    GROUP BY user_id order by points desc) a, (SELECT@rank := 0) vars;

这里有 SQL 演示 http://sqlfiddle.com/#!9/0e8634/2

Answer 2

我会改变这个条件

date_created LIKE '%2019-11%'

进入

month(date_created) = '11' and year(date_created) = '2019'

最终查询，按点 desc 对行进行排序，并使用row_numbers() 或danse_rank() 创建排名。

函数row_numbers()和danse_rank()是从MySQL version >= 8和MariaDB >= 10.2.0.开始引入的

对于较新的版本（MySQL version >= 8 或 MariaDB >= 10.2.0.）

    SELECT SUM(total_distance) as points, user_id, date_created, 
    ROW_NUMBER() OVER (ORDER BY points desc) as rank

    FROM workouts 

    WHERE month(date_created) = '11' AND year(date_created) = '2019' AND activity_type='Run' 
    GROUP BY user_id
    ORDER BY points desc

对于旧版本（MySQL version < 8 或 MariaDB < 10.2.0.）

这也适用于（MySQL version >= 8 OR MariaDB >= 10.2.0.）

    SET @rank=0;
    SELECT SUM(total_distance) as points, user_id, date_created, 
    @rank:=@rank+1 as rank

    FROM workouts 

    WHERE month(date_created) = '11' AND year(date_created) = '2019' AND activity_type='Run' 
    GROUP BY user_id
    ORDER BY points desc