The Table inheritance was functionality introduced in AX2012. You can this way make tables inhering from a base table with the 'Support Inheritance' and 'Extends' properties on the table. DirPartyTable is a standard example using this functionality. But also EcoResProduct. I’m using it now in D365FO on a custom table and I want to add an index containing a field from the ‘parent’ table and a field from the ‘child’ table. Dynamics won't let me do this in the AOT however. Whereas it would be perfectly possible on SQL as Dynamics 'flattens' this table and makes one large table in SQL containg all the fields from the parent table as well as all the child tables. So adding an index containing fields from the parent table as well as the child table is perfectly possible and makes perfect sense to SQL. We also do get the suggestions in our customization by SQL to add these kind of indexes. However as Dynamics won't let us do this, we are not able to create these kind of indexes. I think this is a flaw in the Table inheritance framework which could be solved. We got feedback from Microsoft this idea to solve this is in the Engineering's backlog for implementation. But they have no ETA on this yet. This will be considered based on the priority. The support engineer proposed to create this idea, to get positive responses to get this idea up the priority list. I think there must be other customers/partners using this Table inheritance feature, who are really missing this function to create indexes to make there code run smooth. thanks in advance for supporting this idea!