If I have a column in a table of type TIMESTAMP
and has as default: CURRENT_TIMESTAMP does this column get updated to the current timestamp if I update the value
of any other column in the the same row?
It seems that it does not but I am not sure if this is what should happen.
I can not understand what this means (from MySQL documentation):
If the column is auto-updated, it is automatically updated to the current timestamp when the value of any other column in the row is changed from its current value. The column remains unchanged if all other columns are set to their current values. To prevent the column from updating when other columns change, explicitly set it to its current value. To update the column even when other columns do not change, explicitly set it to the value it should have]2
An auto-updated column is automatically updated to the current timestamp when the value of any other column in the row is changed from its current value. An auto-updated column remains unchanged if all other columns are set to their current values.
To explain it let's imagine you have only one row:
-------------------------------
| price | updated_at |
-------------------------------
| 2 | 2018-02-26 16:16:17 |
-------------------------------
Now, if you run the following update column:
update my_table
set price = 2
it will not change the value of updated_at, since price value wasn't actually changed (it was already 2).
But if you have another row with price value other than 2, then the updated_at value of that row (with price <> 3) will be updated to CURRENT_TIMESTAMP.
I think you have to define the timestamp column like this
CREATE TABLE t1 ( ts TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP );
See here
Adding where to find UPDATE CURRENT_TIMESTAMP
because for new people this is a confusion.
Most people will use phpmyadmin or something like it.
Default value you select CURRENT_TIMESTAMP
Attributes (a different drop down) you select UPDATE CURRENT_TIMESTAMP
Add a trigger in database:
DELIMITER //
CREATE TRIGGER update_user_password
BEFORE UPDATE ON users
FOR EACH ROW
BEGIN
IF OLD.password <> NEW.password THEN
SET NEW.password_changed_on = NOW();
END IF;
END //
DELIMITER ;
The password changed time will update only when password column is changed.
Source: Stackoverflow.com