[MySQL] mysql 5.5和 5.6 timestamp default 默认值CURRENT_TIMESTAMP问题
2023-02-18 15:41:29 时间
TIMESTAMP在MySQL5.5中的行为:
1.第一个未设置默认值的TIMESTAMP NOT NULL字段隐式默认值：CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
2.后面未设置默认值的TIMESTAMP NOT NULL字段隐式默认值：0000-00-00 00:00:00
3.不支持多个CURRENT_TIMESTAMP 默认值
5.5的建表语句类似这样:
CREATE TABLE `audit_log` ( `id` int(10) unsigned NOT NULL AUTO_INCREMENT, `ent_id` int(10) unsigned NOT NULL DEFAULT '0', `rule_id` int(10) unsigned NOT NULL DEFAULT '0', `rules_detail` varchar(2048) NOT NULL DEFAULT '' COMMENT '规则详情', `sender_email` varchar(512) NOT NULL DEFAULT '' COMMENT '发件人被审核邮箱', `receiver_email` varchar(512) NOT NULL DEFAULT '' COMMENT '收件人邮箱', `subject` varchar(512) NOT NULL DEFAULT '' COMMENT '主题', `createtime` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP, `start_time` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00', `end_time` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00', `status` tinyint(3) unsigned NOT NULL DEFAULT '1' COMMENT '当前状态(1 通过,2 拒绝,3 超时拒绝,4 超时通过)', `reviewer_leader` varchar(512) NOT NULL DEFAULT '' COMMENT '审核人', PRIMARY KEY (`id`), KEY `idx_ent_id` (`ent_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COMMENT='审核日志表'
TIMESTAMP在MySQL5.6中的行为:
支持多个CURRENT_TIMESTAMP 默认值,但是不支持设置默认值为0000-00-00 00:00:00
5.6的可以这样:
`createtime` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
`start_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
`end_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,