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# hour
## description
### Syntax

`INT HOUR(DATETIME date)`


获得日期中的小时的信息，返回值范围从0-23。

参数为Date或者Datetime类型

## example

```
mysql> select hour('2018-12-31 23:59:59');
+-----------------------------+
| hour('2018-12-31 23:59:59') |
+-----------------------------+
|                          23 |
+-----------------------------+
```
##keyword
HOUR