mysql数据库CURRENT _mysql5.6、sqlyog

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！
1mysql查询列转当作字符串group_concat
1mysql数据库的共享锁
1mysql怎么返回事务的错误信息

需要这些哦
mysql5.6、sqlyog
方式/
1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

2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');
【mysql数据库CURRENT】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');

3时候戳根基的用法，它暗示当前时候：
SELECT CURRENT_TIMESTAMP,NOW();

4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');

5查询表中所稀有据：SELECT * FROM chengshi;
shijian字段酿成录入时候。

6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;

mysql数据库CURRENT

猜你喜欢