mysql中CURRENT_TIMESTAMP时候戳是当前日期和时候(datetime),我和大师分享一下用法,我写的经验对你进修mysql有帮忙的话,给我投票、点赞或者保藏!
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登录mysql,在test数据库中新建 一个表,shijian字段是timestamp 类型,默认是CURRENT_TIMESTAMP ,只要增添更新shijian字段会变为当前时候:
Create Table
CREATE TABLE `chengshi` ( `id` int(11) NOT NULL AUTO_INCREMENT, `shengfen` varchar(10) DEFAULT NULL, `chengshi` varchar(10) DEFAULT NULL, `shijian` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, PRIMARY KEY (`id`)) ENGINE=InnoDB AUTO_INCREMENT=10 DEFAULT CHARSET=utf8
在表中增添一些数据:
insert into `chengshi` (`id`, `shengfen`, `chengshi`, `shijian`) values('1','河南','安阳','2019-03-05 10:14:27');
insert into `chengshi` (`id`, `shengfen`, `chengshi`, `shijian`) values('2','河南','郑州','2019-03-05 10:14:27');
insert into `chengshi` (`id`, `shengfen`, `chengshi`, `shijian`) values('3','河南','洛阳','2019-03-05 10:14:27');
insert into `chengshi` (`id`, `shengfen`, `chengshi`, `shijian`) values('4','河南','漯河','2019-03-05 10:14:27');
insert into `chengshi` (`id`, `shengfen`, `chengshi`, `shijian`) values('5','河南','新乡','2019-03-05 10:14:27');
insert into `chengshi` (`id`, `shengfen`, `chengshi`, `shijian`) values('6','河南','濮阳','2019-03-05 10:14:27');
insert into `chengshi` (`id`, `shengfen`, `chengshi`, `shijian`) values('7','河南','焦作','2019-03-05 10:14:27');
insert into `chengshi` (`id`, `shengfen`, `chengshi`, `shijian`) values('8','河南','鹤壁','2019-03-05 10:14:27');
insert into `chengshi` (`id`, `shengfen`, `chengshi`, `shijian`) values('9','河南','开封','2019-03-05 10:14:27');
时候戳根基的用法,它暗示当前时候:
SELECT CURRENT_TIMESTAMP,NOW();
在表中增添一个数据,看shijian字段为挂号时候,
INSERT INTO chengshi(shengfen,chengshi)VALUES('河南','信阳');
查询表中所稀有据:SELECT * FROM chengshi;
shijian字段酿成录入时候。
把id=1的记实chengshi='安阳林州',看shijian字段有没有转变 :
UPDATE chengshi SET chengshi='安阳林州' WHERE id=1;
查询表中所稀有据:SELECT * FROM chengshi;
shijian字段酿成更新时候。
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