Description
获得日期中的小时的信息。
参数为 Date 或者 Datetime，Time 类型
当参数为 Date 或者 Datetime，返回值范围从 0-23。当参数为 Time，返回值可以大于 24
Syntax
INT HOUR(DATETIME date)
Example
mysql> select hour('2018-12-31 23:59:59');
+-----------------------------+
| hour('2018-12-31 23:59:59') |
+-----------------------------+
| 23 |
+-----------------------------+
mysql> select cast(4562632 as time),hour(cast(4562632 as time)), minute(cast(4562632 as time)),second(cast(4562632 as time));
+-----------------------+-----------------------------+-------------------------------+-------------------------------+
| cast(4562632 as TIME) | hour(cast(4562632 as TIME)) | minute(cast(4562632 as TIME)) | second(cast(4562632 as TIME)) |
+-----------------------+-----------------------------+-------------------------------+-------------------------------+
| 456:26:32 | 456 | 26 | 32 |
+-----------------------+-----------------------------+-------------------------------+-------------------------------+Keywords
HOUR