Before you go on, I'm specifically worried at the moment about "Logic Intensive Systems" here. Systems that perform complex calculations, make optimizations, determinations, decisions, etc. Many, if not most, enterprise applications have both an object model and the database model. For...

...you don't know where they've been, or who's been touching them. I've been burned pretty badly in the past by making assumptions about existing databases. Database documentation isn't always helpful either, because it is out of date or just wrong to begin with. Even if the documentation is "correct...