关于日期截取的数据库函数(Extract);

Extract函数:作用于数据库数据类型的日期类型(Date,DateTime等),将日期类型进行截取;

简单语法: extract   (   year | month | day | hour | minute | second from 表中是日期类型的字段 ) As 别名

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1.创建含有Date类型的表并导入数据;

create table `tb_user`(
    `user_id` int ,
    `name` varchar(10),
    `bir` datetime
);

insert into
 tb_user 
values(1,'Tom','2019-9-20 21:32:12'),
        (2,'Rose','2018-9-24 01:32:12'),
            (3,'Jake','2018-8-24 01:32:00');

2.利用extract函数进行截取;

select 
  extract(year from bir) as year,
      extract(month from bir) as month,
          extract(day from bir) as day,
              extract(hour from bir) as hour,
                  extract(minute from bir) as min,
                          extract(second from bir) as sec 
from 
tb_user;

3.结果显示