This is fine as a technical exercise, but trusting Oracle is a very bad idea for numerous reasons if your data is not mirrored or backed up elsewhere.
Sufficiently different that you wouldn't backup your data at more locations? I don't think there is a single provider I'd trust that much, at least for data I really need to be still exist while I'm alive.
It's when you're in production and particularly as a billion+ dollar company that screws get properly tightened!
But from the time I was a student in 90s to occasional dabbler now, I find their free / personal / individual / non-prod offerings to in fact be extremely generous.