MySQL 如何求当前月份的记录总和

要求当前月份的记录总和，可以使用SUM()和MONTH()函数。让我们首先创建一个表 −

mysql> create table DemoTable1889
   (
   DueDate date,
   Amount int
   );
Query OK, 0 rows affected (0.00 sec)

使用insert命令向表中插入一些记录 −

mysql> insert into DemoTable1889 values('2019-12-11',500);
Query OK, 1 row affected (0.00 sec)
mysql> insert into DemoTable1889 values('2019-11-11',1000);
Query OK, 1 row affected (0.00 sec)
mysql> insert into DemoTable1889 values('2018-12-04',700);
Query OK, 1 row affected (0.00 sec)
mysql> insert into DemoTable1889 values('2017-12-10',300);
Query OK, 1 row affected (0.00 sec)

使用select语句显示表中的所有记录 −

mysql> select * from DemoTable1889;

这将产生以下输出 −

+------------+--------+
| DueDate    | Amount |
+------------+--------+
| 2019-12-11 |    500 |
| 2019-11-11 |   1000 |
| 2018-12-04 |    700 |
| 2017-12-10 |    300 |
+------------+--------+
4 rows in set (0.00 sec)

当前日期如下 −

mysql> select curdate();
+------------+
| curdate()  |
+------------+
| 2019-12-10 |
+------------+
1 row in set (0.00 sec)

以下是在MySQL中求当前月份的记录总和的查询语句 −

mysql> select sum(Amount) from DemoTable1889 where MONTH(DueDate)=MONTH(curdate());

这将产生以下输出 −

+-------------+
| sum(Amount) |
+-------------+
|        1500 |
+-------------+
1 row in set (0.00 sec)

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