MySQL EXTRACT() 函数
定义和用法
EXTRACT() 函数用于返回日期/时间的单独部分,比如年、月、日、小时、分钟等等。
语法
- EXTRACT(unit FROM date)
date 参数是合法的日期表达式。unit 参数可以是下列的值:
Unit 值 |
---|
MICROSECOND |
SECOND |
MINUTE |
HOUR |
DAY |
WEEK |
MONTH |
QUARTER |
YEAR |
SECOND_MICROSECOND |
MINUTE_MICROSECOND |
MINUTE_SECOND |
HOUR_MICROSECOND |
HOUR_SECOND |
HOUR_MINUTE |
DAY_MICROSECOND |
DAY_SECOND |
DAY_MINUTE |
DAY_HOUR |
YEAR_MONTH |
实例
假设我们有如下的表:
OrderId | ProductName | OrderDate |
---|---|---|
1 | 'Computer' | 2008-12-29 16:25:46.635 |
我们使用下面的 SELECT 语句:
- SELECT EXTRACT(YEAR FROM OrderDate) AS OrderYear,
- EXTRACT(MONTH FROM OrderDate) AS OrderMonth,
- EXTRACT(DAY FROM OrderDate) AS OrderDay
- FROM Orders
- WHERE OrderId=1
结果:
OrderYear | OrderMonth | OrderDay |
---|---|---|
2008 | 12 | 29 |