(转）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

TBL_FUND_FROZEN_UNFROZEN_RECORD

(

ID BIGINT NOT NULL AUTO_INCREMENT,

TRADE_FLOW_ID VARCHAR(60) NOT NULL,

ACCOUNT_NO VARCHAR(32),

INITIATOR VARCHAR(16),

CREATE_DATE TIMESTAMP default CURRENT_TIMESTAMP,

OPERATE_TYPE VARCHAR(32) NOT NULL,

FROZEN_AMOUNT DECIMAL(18,2) DEFAULT 0.0 NOT NULL,

UNFROZEN_AMOUNT DECIMAL(18,2) DEFAULT 0.0,

CREDENTIAL VARCHAR(40) NOT NULL,

MODIFY_DATE TIMESTAMP default CURRENT_TIMESTAMP,

UNFROZEN_DATE TIMESTAMP,

SERIAL_NUM BIGINT NOT NULL,

VERSION BIGINT,

DECRIPTION VARCHAR(200),

CONSTRAINT P_Key_1 PRIMARY KEY (ID)

)ENGINE=InnoDB DEFAULT CHARSET=utf8;

使用函数的方式解决该问题：

通过如下方式指定时间戳类型：

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() 
);

进行如下测试，验证功能是否生效：

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)

文章出处：

http://stackoverflow.com/questions/267658/having-both-a-created-and-last-updated-timestamp-columns-in-mysql-4-0

http://blog.163.com/user_zhaopeng/blog/static/166022708201252323942430/