REAL Server 2011.3
REAL Server is the ideal database server for developers who want to convert a single user database to a multi-user one. It’s fast, has a small footprint, is highly reliable and runs on Windows, Mac and Linux.
REAL Server is fully ACID compliant. ACID stands for atomic, consistent, isolated, and durable and it deals with reliability of database transactions. This is important because it means that you don't have to worry about users accessing the database in an unfinished state. Users can't see changes that are being made but have not been committed. If the server loses power or crashes in the middle of a transaction, the server is restored to its untouched state automatically. ACID compliance is critical to any database you depend on.