Sorry, rinigus, maybe I did not express myself clearly. The point of entering the data that way is that it reduces the possibility for a human error. Furthermore, the application can then format the query in whatever suitable form it likes.

Thanks for the link, BTW. It confirms that there is a hierarchy, albeit not as simple as I had imagined, which only strengthens the need for some abstraction. A layer that removes that complexity from the user. I understand that it would not be straightforward. You would need a per-country hierarchy table and a dynamic number of entry fields, plus a clever algorithm. Which is why it is my wish, but not necessarily a request