cubeSQL (formely REAL Server) is a fully featured and high performance relational database management system built on top of the sqlite database engine.
cubeSQL is incredibly fast, has a small footprint, is highly reliable and runs on Windows, Mac and Linux (32 bit and 64 bit for all platforms). cubeSQL can be accessed with PHP, JSON, REAL Studio and with the native C SDK.
cubeSQL is written in low level ANSI C so it can be easily ported to other operating systems.