I answer lots of questions about Oracle. Many of them are ambiguous, unclear, not fully specified, hard to follow. It is like unraveling a puzzle sometimes (ok, most of the times...)
That is why I found this question to be really amusing - especially after reading the comments. Lots of disagreement as to the meaning of the question!
So, what do you think the answer is... I'll post what I think after I see some feedback. It is a very very interesting question.
And it also points to why I think the answer to all questions is mostly "Why" or "It depends". We usually need a lot more information to answer what might appear to be simple questions.