[maddinat0r]

Imagine you want to create a dialog which lists all of your cars and if you click on one of the car you get another dialog where you can edit it.
Without cache_save and _delete you would first send a query, then use the result to display the list dialog. After the player chooses the car, you would have to send the same query again and then get the car-data.
With cache_save and _delete you send a query, save the result with cache_save and display the list dialog. After the player chooses the car, you set the saved cache as active and get the car-data.
With cache_save you saved a query. That's one example how these new functions can be used for optimization.