SQL语句：按天、月、年对数据求和

使用SQL语句按天、月、年对数据求和

本篇介绍了使用SQL语句对数据进行按天、月、年求和的代码示例，并提供了详细的解释和注意事项。

1. 按天求和

SELECT date, SUM(value) AS total_value 
FROM table_name 
GROUP BY date 
ORDER BY date ASC;

2. 按月求和

SELECT DATE_FORMAT(date, '%Y-%m') AS month, SUM(value) AS total_value 
FROM table_name 
GROUP BY month 
ORDER BY month ASC;

3. 按年求和

SELECT YEAR(date) AS year, SUM(value) AS total_value 
FROM table_name 
GROUP BY year 
ORDER BY year ASC;

**注意：**以上SQL语句仅供参考，具体实现可能需要根据实际情况进行修改。