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mysql建表设置两个默认CURRENT_TIMESTAMP的技巧

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…