Schedule update with specific new data in MySQL table - mysql

Question

I'm wondering if there is any way to schedule an update where I update a tables data on expiration of the old one.
E.g. John Smith has an active service at Company X, but wants to upgrade the service. However, due to restrictions to his current agreement the new service doesn't take effect until X days.
Is there any way to store the new data and update it at the end of a month in MySQL? If yes, would this require me to have another table with the new order data stored?

Answer 1

Often this requirement for changing things at future times is handled by placing start_date and end_date columns in your services table.
Then you can find presently active service rows with
SELECT user_id, whatever, whatelse
FROM services
WHERE (start_date IS NULL OR start_date <= NOW())
AND (end_date IS NULL OR end_date > NOW());
You can, if you wish, create a view called active_services automatically filtering the services table for currently active services.
CREATE VIEW active_services AS
SELECT *
FROM services
WHERE (start_date IS NULL OR start_date <= NOW())
AND (end_date IS NULL OR end_date > NOW());
Note -- in this design end_date contains not the last moment the service is active but the first moment it becomes inactive. If end_date is null the service continues to be active.
To change a service or user_id at the beginning of next month you do these two operations:
UPDATE service
SET end_date = LAST_DAY(NOW()) + INTERVAL 1 DAY
WHERE user_id = <<user id you wish to change >>
INSERT INTO service (start_date, user_id, whatever, whatelse)
VALUES (LAST_DAY(NOW()) + INTERVAL 1 DAY,
<<user id you wish to change >>,
<<whatever>>,
<<whatelse>>;
Then, when next month arrives the active_services view returns the new service. This is much more robust than relying on a precisely timed monthly job. If you do a monthly job, it can run anytime. It simply cleans up expired services.
You can use MySQL events to run particular jobs at appointed times. (But some shared MySQL systems don't let you use events.)

Answer 2

Interestingly mysql has event schedulers have a look at the documentation.
below is an example of a minimal CREATE EVENT statement:
CREATE EVENT myevent
ON SCHEDULE AT CURRENT_TIMESTAMP + INTERVAL 1 HOUR
DO
UPDATE myschema.mytable SET mycol = mycol + 1;
The previous statement creates an event named myevent. This event executes once—one hour following its creation—by running an SQL statement that increments the value of the myschema.mytable table's mycol column by 1.
If yes, would this require me to have another table with the new order data stored
I am not sure if you need another table or so...it purely depends on how you want it to be one