MySQL5.7: datetime

-- 當前日期時間
 select now();
 select now(3);-- 保留3位毫秒數
 
 SELECT NOW(6); -- 保留6位毫秒數
 -- 當前日期和時間 至秒
 select current_timestamp; 
 select current_timestamp(3);
 select current_timestamp(6); 
 
 -- 當前日期，不包括時間
 
 select curdate();
 -- 當前時間
 select curtime();
 
 select DATE_FORMAT('2010-12-01 06:03:16.233999','%Y-%m-%d %T:%f');
 
select DATE_FORMAT('2010-12-01 07:03:16','%Y-%m-%d %h:%i:%s');

 select timestampadd(hour, -8, '2008-08-08 12:00:00');  
 select date_add('2008-08-08 12:00:00', interval -8 hour); 
 
 select get_format(date,'iso');
 select get_format(datetime,'iso');
 select period_diff(200808, 200801);
 select timestampdiff(year,'2002-05-01','2001-01-01');
 -- 
 drop table datetest;
 
 
 CREATE TABLE `datetest` (
`time_id`  int PRIMARY KEY auto_increment  comment '自動增長ID',
`CoAction` nvarchar(100) null default '', 
`createdate` TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3), -- 保留3位毫秒數
`createdate2` DATETIME(3) NOT NULL DEFAULT now(3),
`createdate3` TIMESTAMP(6) NOT NULL DEFAULT CURRENT_TIMESTAMP(6),  --  CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
`createdate4` DATETIME(6) NOT NULL DEFAULT now(6)  -- 保留6位毫秒數
) ENGINE=INNODB DEFAULT CHARSET=utf8 COMMENT='時間格式測試' AUTO_INCREMENT=1;

SELECT * FROM datetest;

insert into datetest(CoAction) values('geovindu,塗聚文');