I have a table with two timestamp fields formed with -
CREATE TABLE `test`
(`id` INT NOT NULL AUTO_INCREMENT ,
`first_date` TIMESTAMP NULL ,
`second_date` TIMESTAMP on update CURRENT_TIMESTAMP() NULL ,
PRIMARY KEY (`id`)) ENGINE = InnoDB;
I inserted two rows using
INSERT INTO `test` (`id`, `first_date`, `second_date`)
VALUES (NULL, NULL, '2017-10-18 17:02:14'), (NULL, NULL, '2017-10-18 17:02:14');
Now, I need to copy the second date value to the first date column, but when I try the update query both the date value get updated to today's date.
update test set first_date = second_date where id=<row_id>
id | first_date | second_date
----------------------------------------------
3 | 2017-11-17 16:09:03 | 2017-11-17 16:09:29 --> This value was
4 | NULL | 2017-10-18 17:02:14 "2017-10-18 17:02:14"
5 | NULL | 2017-10-18 17:02:14 before the update query.
Somehow, the on update CURRENT_TIMESTAMP()
attribute of the second_date is creating a problem here. How would I copy the value from second column without affecting the existing value of second_date
?