MySQL CURRENT_TIMESTAMP on create and on update
I want to define table which will have 2 TIMESTAMP fields, someting like this:
CREATE TABLE `msgs` (
`id` INT PRIMARY KEY AUTO_INCREMENT,
`msg` VARCHAR(256),
`ts_create` TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
`ts_update` TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
)
How to do this avoiding error:
ERROR 1293 (HY000): Incorrect table definition; there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT or ON UPDATE clause
Point is to keep desired behavior of ts_cre开发者_开发知识库ate
and ts_update
in table schema.
Guess this is a old post but actually i guess mysql supports 2 TIMESTAMP in its recent editions mysql 5.6.25 thats what im using as of now.
i think it is possible by using below technique
`ts_create` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',
`ts_update` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
You are using older MySql version. Update your myqsl to 5.6.5+ it will work.
You cannot have two TIMESTAMP column with the same default value of CURRENT_TIMESTAMP on your table. Please refer to this link: http://www.mysqltutorial.org/mysql-timestamp.aspx
I think you maybe want ts_create as datetime (so rename -> dt_create) and only ts_update as timestamp? This will ensure it remains unchanging once set.
My understanding is that datetime is for manually-controlled values, and timestamp's a bit "special" in that MySQL will maintain it for you. In this case, datetime is therefore a good choice for ts_create.
I would say you don't need to have the DEFAULT CURRENT_TIMESTAMP on your ts_update: if it is empty, then it is not updated, so your 'last update' is the ts_create.
This is the tiny limitation of Mysql in older version , actually after version 5.6 and later multiple timestamps works...
you can try this
ts_create
TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
ts_update
TIMESTAMP DEFAULT NULL ON UPDATE CURRENT_TIMESTAMP
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