SharePoint 2010 With Oracle Database

Hello All, I am asked to design a portal having all of its content saved on an Oracle DB. Including (Claims Based Authentication Info, Roles & Lists)
Is it possible to make SharePoint connects to an Oracle Db instead of SQL and automatically save everything to it?

If Not, what is the other alternatives?

Is using BCS will help me by any mean, as all i can see that it will affect the performance and won't help me in anything (can't see any advantage for using it) as i will still have to implement a Data Access Layer?

Or Shall i instead generate the ordinary Data Access Layer that connects directly to the Oracle DB and retrieves the values?

Thank you for your help