Question

我正在尝试使用join查询表，但我无法在这里获得成功

Score
id    ,  user_id    ,     score  ,   week
1     ,   123       ,      2     ,    1
2     ,   432       ,      2     ,    1  
3     ,   432       ,      3     ,    1
4     ,   123       ,      2     ,    2

我想在第1周和第2周的最大总和之和的基础上查询前20位用户记录

我希望结果应该是

id      , user_id     , week1score    , week2score
1       ,  123        ,  2            ,  2
2       ,  432        ,  3            ,  0

公式是降序和（max（week1）+ max（week2））

的顺序

由于 INAM

Answer 1

这样的事情

SELECT t1.user_id, 
       SUM(week1score) AS week1score, 
       SUM(week2score) AS week2score 
FROM   (SELECT user_id 
        FROM   `table` 
        GROUP  BY user_id) AS t1 
       JOIN (SELECT user_id, 
                    Max(IF(`week` = 1, score, 0)) AS week1score, 
                    Max(IF(`week` = 2, score, 0)) AS week2score 
             FROM   `table` 
             GROUP  BY user_id, 
                       `week`) t2 
         ON t2.user_id = t1.user_id 
GROUP  BY user_id 
ORDER  BY ( SUM(week1score) + SUM(week2score) ) DESC

您需要以下列的复合索引

（USER_ID，周，评分）

如何获取多个最大列值mysql

1 个答案: