MySQL嵌套优化

Question

我已经试了2个小时来解决这个问题，但是没有成功

下面是对此查询的响应：

SELECT login, SUM(gain) AS weekly_gain
FROM gt_history
WHERE is_closed = 1 AND (cmd = 0 OR cmd = 1)
GROUP BY WEEK(close_time), login

现在，我想要做的是，为所有值创建一个AVERAGE，GROUP BY登录。

想法？

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Answer 1

只需使用您已有查询作为子查询。

SELECT login, AVG(weekly_gain) FROM
    (SELECT login, SUM(gain) AS weekly_gain
    FROM gt_history
    WHERE is_closed = 1 AND (cmd = 0 OR cmd = 1)
    GROUP BY WEEK(close_time), login)
GROUP BY login

Answer 2

SELECT
  login,
  AVG(weekly_gain) AS weekly_gain
FROM (SELECT
    login,
    SUM(gain) AS weekly_gain
      FROM gt_history
      WHERE is_closed = 1
      AND (cmd = 0
        OR cmd = 1)
      GROUP BY WEEK(close_time), login) As l