首页 > 解决方案 > 按月分组,具有总和值和滚动年份

问题描述

我正在尝试在 MySQL 中按月对销售数据进行分组,但使用滚动年总和值。示例预期输出:

Month                           SUM
January 2018    Total from february 2017 to january 2018 (12months)
February 2018   Total from march 2017 to february 2018 (12months)
...

这是我到目前为止得到的:

SELECT YEAR(date), MONTH(date), 
(SELECT SUM(quantity) FROM tb t2 WHERE t2.date BETWEEN DATE_SUB(t1.date, INTERVAL 1 YEAR) AND t1.date)
FROM tb t1
WHERE date BETWEEN '2018-01-01' AND '2019-01-01'
GROUP BY YEAR(date), MONTH(date)

结果是预期的,但是效率很低,因为如果我使用 3 天的间隔运行它需要 30 秒(所以我什至不能以 1 年的间隔运行它)

任何想法如何改进此查询,以便我可以使用 1 年的时间间隔?特定字段是否需要索引?

编辑:创建语句:

CREATE TABLE IF NOT EXISTS `tb` (
  `inc` int(11) NOT NULL AUTO_INCREMENT,
  `quantity` float NOT NULL,
  `date` datetime NOT NULL,
  PRIMARY KEY (`inc`),
  KEY `date` (`date`)
) ENGINE=InnoDB;

它有超过 100k 行,我无法升级到 MySQL >= 8

标签: mysqldategroup-by

解决方案


代替使用子查询,“自内连接”可以更有效。请尝试以下操作:

SELECT 
  YEAR(t1.date), 
  MONTH(t1.date), 
  SUM(t2.quantity) 
FROM tb AS t1 
JOIN tb AS t2 
  ON t2.date BETWEEN (t1.date - INTERVAL 1 YEAR) AND t1.date 
WHERE t1.date BETWEEN '2018-01-01' AND '2019-01-01'
GROUP BY YEAR(t1.date), MONTH(t1.date)

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