MySQL 如何从日期记录中显示月份的第一天和最后一天

首先让我们创建一个表 –

mysql> create table DemoTable
   -> (
   -> DueDate date
   -> );
Query OK, 0 rows affected (0.73 sec)

使用insert命令向表中插入一些记录 –

mysql> insert into DemoTable values('2019-01-11');
Query OK, 1 row affected (0.08 sec)
mysql> insert into DemoTable values('2019-04-19');
Query OK, 1 row affected (0.14 sec)

使用select语句显示表中的所有记录 –

mysql> select *from DemoTable;

这将产生以下输出 –

+------------+
| DueDate    |
+------------+
| 2019-01-11 |
| 2019-04-19 |
+------------+
2 rows in set (0.00 sec)

以下是显示月份的第一天和最后一天的查询 –

mysql> select date_format(DueDate,'%Y-%m-01') as FirstDayOfMonth,last_day(DueDate) as LastDayOfMonth from DemoTable;

这将产生以下输出 –

+-----------------+----------------+
| FirstDayOfMonth | LastDayOfMonth |
+-----------------+----------------+
| 2019-01-01      | 2019-01-31     |
| 2019-04-01      | 2019-04-30     |
+-----------------+----------------+
2 rows in set (0.00 sec)