在 MySQL 中将 varchar 转换为 datetime 并进行比较?
mysqlmysqli database
为此，您可以使用 STR_TO_DATE()。让我们首先创建一个表 −
mysql> create table DemoTable1565 -> ( -> ArrivalDatetime varchar(40) -> ); Query OK, 0 rows affected (0.82 sec)
使用 insert 命令在表中插入一些记录 −
mysql> insert into DemoTable1565 values('10/01/2019 21:29:35');
Query OK, 1 row affected (0.22 sec)
mysql> insert into DemoTable1565 values('10/13/2019 4:56:00');
Query OK, 1 row affected (0.14 sec)
mysql> insert into DemoTable1565 values('10/13/2018 12:40:46');
Query OK, 1 row affected (0.10 sec)
mysql> insert into DemoTable1565 values('10/13/2019 21:30:00');
Query OK, 1 row affected (0.58 sec)
使用 select 语句显示表中的所有记录 −
mysql> select * from DemoTable1565;
这将产生以下输出 −
+---------------------+ | ArrivalDatetime | +---------------------+ | 10/01/2019 21:29:35 | | 10/13/2019 4:56:00 | | 10/13/2018 12:40:46 | | 10/13/2019 21:30:00 | +---------------------+ 4 rows in set (0.00 sec)
当前日期如下 −
mysql> select now(); +---------------------+ | now() | +---------------------+ | 2019-10-13 21:34:14 | +---------------------+ 1 row in set (0.00 sec)
这是从 varchar 转换为 datetime 并进行比较的查询 −
mysql> select * from DemoTable1565 where str_to_date(ArrivalDatetime,'%m/%d/%Y')=curdate();
这将产生以下输出 −
+---------------------+ | ArrivalDatetime | +---------------------+ | 10/13/2019 4:56:00 | | 10/13/2019 21:30:00 | +---------------------+ 2 rows in set, 4 warnings (0.03 sec)
