how would that work ?  For OutSystems static entities, the platform is able to expose the records as discrete items to be used in the code, but that is only possible because the platform controls the values at design time.  External database tables are outside of the platform's control.

That's a great question @Dorine Boudry and my simple answer is I don't know because I don't have any insight in to OutSystem's internal programming. 

The non-simple answer is that the components are all there nonetheless. An external table will define its columns and their data types just as a static entity does and the entries would need to be inferred and converted to a static entity. Maybe that inference is automatic, maybe it requires someone clicking a button when an update is needed (similar to external database column updates today) but yes it absolutely would need to be a design time operation. At any rate, what I can say is its entirely possible as the pieces are all there. 

the point is that there is nothing stopping anybody from messing with the data if they are not in control of the platform, so that would be a very fragile thing to do.

@Dorine Boudry for sure. It's the same with external tables though, there's nothing stopping anyone from completely changing their shape and a level of fragility that comes with that. Its just a matter of governance that is outside of OutSystem's control plane.