MYSQL中TIMESTAMP类型可以设定默认值,就像其他类型一样。
1、自动UPDATE 和INSERT 到当前的时间:
表:
/*DDL Information For - test.t1*/
---------------------------------
Table Create Table
------ -------------------------------------------------------------------------------------
t1 CREATE TABLE `t1` (
`p_c` int(11) NOT NULL,
`p_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
) ENGINE=InnoDB DEFAULT CHARSET=gb2312
数据:
1 2007-10-08 11:53:35
2 2007-10-08 11:54:00
insert into t1(p_c) select 3;
update t1 set p_c = 2 where p_c = 2;
数据:
1 2007-10-08 11:53:35
2 2007-10-08 12:00:37
3 2007-10-08 12:00:37
2、自动INSERT 到当前时间,不过不自动UPDATE。
表:
/*DDL Information For - test.t1*/
---------------------------------
Table Create Table
------ ---------------------------------------------------------
t1 CREATE TABLE `t1` (
`p_c` int(11) NOT NULL,
`p_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP
) ENGINE=InnoDB DEFAULT CHARSET=gb2312
数据:
insert into t1(p_c) select 4;
update t1 set p_c = 3 where p_c = 3;
1 2007-10-08 11:53:35
2 2007-10-08 12:00:37
3 2007-10-08 12:00:37
4 2007-10-08 12:05:19
3、一个表中不能有两个字段默认值是当前时间,否则就会出错。不过其他的可以。
表:
/*DDL Information For - test.t1*/
---------------------------------
Table Create Table
------ ---------------------------------------------------------------
t1 CREATE TABLE `t1` (
`p_c` int(11) NOT NULL,
`p_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
`p_timew2` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00'
) ENGINE=InnoDB DEFAULT CHARSET=gb2312
数据:
1 2007-10-08 11:53:35 0000-00-00 00:00:00
2 2007-10-08 12:00:37 0000-00-00 00:00:00
3 2007-10-08 12:00:37 0000-00-00 00:00:00
4 2007-10-08 12:05:19 0000-00-00 00:00:00
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