In Microsoft Dynamics 365 F&O we can show data on a form that is not directly in that data source of the form but is linked to that data source somehow. Let’s Just say in Purchase Order form we can get the vendor ID but to get the vendor group we need to add the vendor table in the purchase order form. In this case instead of adding another data source we. an just add a display method on the form level or table level.
Also in some scenarios, data is dynamic which means it is not stored in any table and we need to generate it dynamically. In that case, we create a display method on the table level or form level.
Thank you.