MySQL 如何将DATETIME转换为DATE

要在MySQL中将DATETIME转换为DATE，可以使用CAST()函数。语法如下−

select cast(yourColumnName as Date) as anyVariableName from yourTableName;

为了理解上述语法，让我们首先创建一个表−

mysql> create table ConvertDatetimeToDate
−> (
      YourDatetime datetime
      );
Query OK, 0 rows affected (0.95 sec)

使用insert命令将日期时间插入到表中。该查询如下−

mysql> insert into ConvertDatetimeToDate values(date_add(now(),interval 1 day));
Query OK, 1 row affected (0.17 sec)

mysql> insert into ConvertDatetimeToDate values(date_add(now(),interval -1 day));
Query OK, 1 row affected (0.15 sec)

mysql> insert into ConvertDatetimeToDate values(date_add(now(),interval 1 year));
Query OK, 1 row affected (0.10 sec)

mysql> insert into ConvertDatetimeToDate values(date_add(now(),interval -1 year));
Query OK, 1 row affected (0.16 sec)

显示上面插入的所有记录。该查询如下−

mysql> select *from ConvertDatetimeToDate;

结果如下−

+---------------------+
|YourDatetime          |
+---------------------+
| 2018-11-28 16:12:50  |
| 2018-11-26 16:13:00  |
| 2019-11-27 16:13:13  |
| 2017-11-27 16:13:24  |
+---------------------+
4 rows in set (0.00 sec)

现在，您可以应用上述语法将datetime转换为date。该查询如下−

mysql> select cast(YourDatetime as Date) as OnlyDateDemo from ConvertDatetimeToDate;

结果如下−

+--------------+
|OnlyDateDemo   |
+--------------+
| 2018-11-28    |
| 2018-11-26    |
| 2019-11-27    |
| 2017-11-27    |
+--------------+
4 rows in set (0.00 sec)

阅读更多：MySQL 教程