The data-event handlers handle the delegates exposed on every table. These delegates are listed under the Events node.
These events do not fire if the associated method (for example, insert) is overridden on the table and super() is not called.
How the event handler methods are organized is up to the developer; they just need to be placed logically so that others will find them easily.
In our case, the event handler is used purely for a report and populating a field on insert that is used in a report. So, we will place these methods in a helper class.