We are an Oracle database shop. I have an application for which I think Oracle likely isn't the best answer. I am looking for a lightweight, good performing and very secure database. The database itself will have probably a dozen tables and maybe millions of records. I don't need stored procedures, clustering or any of the high-end features.
My ultimate goal is security. I'm looking for built-in encryption, an overall secure design and low-profile to minimize potential security holes.
I'll want to run it on *nix, since they are much easier to make low-profile than Windows.
For example, in the BSD world there are several variants. FreeBSD is the most portable and OpenBSD is the most secure. I'm looking for the OpenBSD of the database world.