如何计算 MySQL 中的多个移动平均线

Question

使用下表，如何获得 5 个周期移动平均线、10 个周期移动平均线、5 个周期指数移动平均线的列。

+--------+------------+
| price  | data_date  |
+--------+------------+
| 122.29 | 2009-10-08 |
| 122.78 | 2009-10-07 |
| 121.35 | 2009-10-06 |
| 119.75 | 2009-10-05 |
| 119.02 | 2009-10-02 |
| 117.90 | 2009-10-01 |
| 119.61 | 2009-09-30 |
| 118.81 | 2009-09-29 |
| 119.33 | 2009-09-28 |
| 121.08 | 2009-09-25 |
+--------+------------+

Answer 1

您示例中的 5 行移动平均线不起作用。 LIMIT 运算符适用于返回集，而不是聚合考虑的行，因此更改它对聚合值没有影响。

Answer 2

SELECT AVG(a.price) FROM (SELECT price FROM t1 WHERE data_date <= ? ORDER BY data_date DESC LIMIT 5) AS a;

代替？ 与您需要其 MA 的日期。

Answer 3

SELECT   t1.data_date, 
( SELECT  SUM(t2.price) / COUNT(t2.price) as MA5 FROM mytable AS t2    WHERE DATEDIFF(t1.data_date, t2.data_date) BETWEEN 0 AND 6 ) 
FROM mytable AS t1   ORDER BY t1.data_date;

将 6 更改为 13 为 10 天均线