mysql 在分组前排序

Question

我认为这是 best solution .然而，这个查询并没有解决我的问题——我喜欢这张表:

+--+-------+-----+
|id|user_id|score|
+--+-------+-----+
|1 |1      |5    |
+--+-------+-----+
|2 |1      |16   |
+--+-------+-----+
|3 |1      |15   |
+--+-------+-----+

查询:

  SELECT *
    FROM (`_scorboard`)
GROUP BY `user_id`
  HAVING `score` = MAX(score)
ORDER BY `score` desc 

result 0 rows

为什么返回0条记录？

Answer 1

使用:

SELECT a.*
  FROM SCOREBOARD a
  JOIN (SELECT t.user_id,
               MAX(t.score) AS max_score
          FROM SCOREBOARD t
      GROUP BY t.user_id) b ON b.max_score = a.score
                           AND b.user_id = a.user_id

如果你想要那些在表格中得分最高的人:

SELECT a.*
  FROM SCOREBOARD a
  JOIN (SELECT MAX(t.score) AS max_score
          FROM SCOREBOARD t) b ON b.max_score = a.score