Select between xpath or oql when using a retrieve action. When oql is selected, it should be possible to select a NPE for the output result.
The OQL statement should be validated like it's done with XPATH and all other options like limit or offset should be available (except sorting perhaps).
----
A nice future feature would be to be able to build an oql query (like dataset) by dragging and dropping entities, and use this inside a retrieve action or any widget that holds a datasource.
As a follow-up to this, XPATH is great if what you want is to return objects. But for any rollup or inventory view, Mendix leaves much to be desired compared to the competition. It would be great if the usability of OQL were to be improved as it really feels like the right abstraction for reporting (vs writing sql directly).
This is absolutely needed to make utilizing OQL maintainable. Right now we have marketplace modules but having to paste the queries in as strings is extremely brittle.