So I've had a few questions on how to install Oracle on a Mac.
Now, I've never tried it, and don't have a Mac to be able to test it, but I've found some instructions that might help.
It's not easy, but these are the best instructions that I've found.
You can read them here:
http://dimitrisli.wordpress.com/2012/08/08/how-to-install-oracle-database-on-mac-os-any-version/
Hope it helps!