Edward,

>> This thread gave many insights but it seems to me that one point was missed. It's possible to have one DE for whole application, i.e.
you still preserve OO approach and at the same time get better speed. <<

Yes, this thread gave me many insights as well. I've been away for a couple of days and when I got back my thread had exploded. I for one feel better knowing other programmers are taking the same approach for lots of reasons, and nobody is getting arrested by the code police.

But I'd like to pin you down on a couple of things:
1. By opening all tables for the whole app, you are trying to cut out an OS call, but are still opening the tables individually in private data sessions?
2. Does this approach work for views? I define typically three views at minimum per table (primary key, surrogate key, non p-view of all records, p-view on lookup fields, and one view per foreign key). On a ten table app I could end up opening 50 or more views with your approach. Any thoughts on the applicability of your approach here?