mysql - 使用不同日期获取不同总计的总和

Question

我有一个交易表，我想在其中计算不同日期的总金额，下面是我的代码

SELECT SUM( total_amount ) AS total FROM transaction WHERE execution_date BETWEEN  "2015-08-1" AND  "2015-08-31" AND execution_date BETWEEN  "2015-09-1" AND  "2015-09-30"

该代码仅返回 Null。欢迎任何帮助。

Answer 1

你应该写OR相反 AND因为您想要显示 2015-08-1" AND "2015-08-31 范围内的交易和2015-09-1" AND "2015-09-30 , 这是矛盾，结果null

SELECT SUM( total_amount ) AS total FROM transaction
 WHERE execution_date BETWEEN "2015-08-1" AND "2015-08-31" 
OR execution_date BETWEEN "2015-09-1" AND "2015-09-30"

或者

SELECT SUM( total_amount ) AS total FROM transaction
     WHERE execution_date BETWEEN "2015-08-1" AND "2015-09-30"

希望这有帮助