让我们首先创建一个表，其中一个列为DueDate，另一个为“ RepeatTime”(重复次数)，该表显示了用户提交付款的次数-mysql> create table DemoTable
-> (
-> DueDate date,
-> RepeatTime int
-> );
Query OK, 0 rows affected (0.57 sec)
使用插入命令在表中插入一些记录-mysql> insert into DemoTable values('2019-01-23',3);
Query OK, 1 row affected (0.13 sec)
mysql> insert into DemoTable values('2019-06-22',6);
Query OK, 1 row affected (0.19 sec)
mysql> insert into DemoTable values('2019-03-28',2);
Query OK, 1 row affected (0.25 sec)
mysql> insert into DemoTable values('2017-07-25',6);
Query OK, 1 row affected (0.15 sec)
使用select语句显示表中的所有记录-mysql> select *from DemoTable;
输出结果
这将产生以下输出-+------------+------------+
| DueDate | RepeatTime |
+------------+------------+
| 2019-01-23 | 3 |
| 2019-06-22 | 6 |
| 2019-03-28 | 2 |
| 2017-07-25 | 6 |
+------------+------------+
4 rows in set (0.00 sec)
这是根据另一列中的值递增日期的查询-mysql> update DemoTable set DueDate=date_add(DueDate,interval RepeatTime MONTH)
where RepeatTime!=6;
Query OK, 2 rows affected (0.25 sec)
Rows matched: 2 Changed: 2 Warnings: 0
让我们再次检查表记录-mysql> select *from DemoTable;
输出结果
这将产生以下输出-+------------+------------+
| DueDate | RepeatTime |
+------------+------------+
| 2019-04-23 | 3 |
| 2019-06-22 | 6 |
| 2019-05-28 | 2 |
| 2017-07-25 | 6 |
+------------+------------+
4 rows in set (0.00 sec)