Someone please help me in choosing whether to use Hibernate or Cayenne?
Which is more suitable to handle large databases?
I used both, but if I was in charge (and not my boss :) ) I would prefer Cayenne.
Cayenne has a very nice CayenneModeler, so you don't have to write any mapping code - just click your way an entire project in a few minutes.
If you have performance sensitive areas in you project, Cayenne has something called SQLTemplate - a very very efficient solution.
And last but not least, as a newbie or as a simple user, you get very fast very good solutions to your questions - as opposed to the Hibernate forums - just look how many questions are unanswered there.