业务场景:
例如用户表,我们需要建一个字段是创建时间, 一个字段是更新时间.
解决办法可以是指定插入时间,也可以使用数据库的默认时间.
在mysql中如果设置两个默认CURRENT_TIMESTAMP,会出现这样的错误.
ERROR 1293 (HY000): Incorrect table definition; there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT or ON UPDATE clause.错误的建表语句:
CREATE TABLE `db1`.`sms_queue` ( `Id` INTEGER UNSIGNED NOT NULL AUTO_INCREMENT, `Message` VARCHAR(160) NOT NULL DEFAULT 'Unknown Message Error', `CurrentState` VARCHAR(10) NOT NULL DEFAULT 'None', `Phone` VARCHAR(14) DEFAULT NULL, `Created` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP, `LastUpdated` TIMESTAMP NOT NULL ON UPDATE CURRENT_TIMESTAMP, `TriesLeft` tinyint NOT NULL DEFAULT 3, PRIMARY KEY (`Id`) ) ENGINE = InnoDB;解决办法,可以使用触发器或者其他,在此还是使用数据库的方式.
建表语句:
create table test_table( id integer not null auto_increment primary key, stamp_created timestamp default '0000-00-00 00:00:00', stamp_updated timestamp default now() on update now() );测试:
mysql> insert into test_table(stamp_created, stamp_updated) values(null, null); Query OK, 1 row affected (0.06 sec)mysql> select * from t5; +----+---------------------+---------------------+ | id | stamp_created | stamp_updated |+----+---------------------+---------------------+| 2 | 2009-04-30 09:44:35 | 2009-04-30 09:44:35 |+----+---------------------+---------------------+2 rows in set (0.00 sec) mysql> update test_table set id = 3 where id = 2; Query OK, 1 row affected (0.05 sec) Rows matched: 1 Changed: 1 Warnings: 0 mysql> select * from test_table;+----+---------------------+---------------------+| id | stamp_created | stamp_updated | +----+---------------------+---------------------+ | 3 | 2009-04-30 09:44:35 | 2009-04-30 09:46:59 | +----+---------------------+---------------------+ 2 rows in set (0.00 sec) 解决办法是在stackoverflow看到的,原文网址:http://stackoverflow.com/questions/267658/having-both-a-created-and-last-updated-timestamp-columns-in-mysql-4-0
转载于:https://www.cnblogs.com/yanduanduan/p/5369325.html
