mysql - 如何计算累计平均值

我想计算数据的累计平均值。

在我的查询中，我现在获得每个日期的总和值。但是我很困惑如何计算累计平均值。

我的查询

SELECT
  u.id,
  (SUM(m.protein)),
  DATE(FROM_UNIXTIME(u.create)) AS Cdate,
  goal.what,
  goal.value
FROM
  `meal` AS m,
  `user_history` AS u
LEFT JOIN goal
    ON goal.what = 'Protein'
    AND goal.user_id = 48
WHERE u.meal_id = m.id
  AND u.user_id = 48
GROUP BY DATE(FROM_UNIXTIME(u.create))

在这里，我得到了sum(m.protein)的总和值，但是我想在这里累积平均值

最佳答案

SET @csum=0;
SELECT
  u.id,
  (SUM(m.protein)) as sum1,
  (@csum := @csum + sum1) as CSUM,
  DATE(FROM_UNIXTIME(u.create)) AS Cdate,
  goal.what,
  goal.value
FROM
  `meal` AS m,
  `user_history` AS u
LEFT JOIN goal
    ON goal.what = 'Protein'
    AND goal.user_id = 48
WHERE u.meal_id = m.id
  AND u.user_id = 48
GROUP BY DATE(FROM_UNIXTIME(u.create))

关于mysql - 如何计算累计平均值，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/24858748/