Event handling is a new and welcome feature in AX from version 2012 onwards. One of its biggest gains is that it helps reduce the footprint on standard software (or that provided by an ISV or a partner). The footprint is one of the biggest concerns when minimizing the impact of future updates and upgrades.
The scenario we are describing is where we subscribe to an event (such as a table's delete method) so that it will call a method that handles the event. Although we add this subscription to a standard object in the AOT, the standard object is not modified. AX stores only the subscription definition. It is represented against the standard code, but this is only to help us intuitively create and manage event subscriptions.
The functionality we are going to provide is as follows:
When scheduling an appointment in transport management, the system has to associate the tractor and trailer with our fleet management system, if it exists. No lookup...