On Sun, Jul 29, 2007 at 07:02:19PM -0700, Eric Bergen wrote:
> That's a much better example. It does seem very strange that the
> timestamp functionality isn't more flexible. I suspect there are other
> things wrong in that area too. While playing around with timestamp
> definitions I found that the on update timestamp column still has to
> be listed before any other timestamps.
>
> I can't find anything in the manual that says the "magic" timestamp
> column still needs to be first like it was in 4.0.
It doesn't.
mysql> create table t1 (a timestamp default 0, b timestamp
-> on update current_timestamp);
Query OK, 0 rows affected (0.01 sec)
mysql> show create table t1\G
*************************** 1. row ***************************
Table: t1
Create Table: CREATE TABLE `t1` (
`a` timestamp NOT NULL default '0000-00-00 00:00:00',
`b` timestamp NOT NULL default '0000-00-00 00:00:00' on update
CURRENT_TIMESTAMP
) ENGINE=MyISAM DEFAULT CHARSET=latin1
I don't know if there is a strong technical reason for only allowing a
single timestamp field to be automatically set or automatically updated,
or the limitation was just a carry-over from when only the first
timestamp field was auto-set/update. I wouldn't expect anyone at MySQL
to jump at implementing this, but a patch would be looked at. (But since
you can get the same effect with a trigger, it may not have a shot.)
Jim Winstead
MySQL Inc.
