User limit: None

Redistributable: Yes.

Platforms: 32-bit Linux and Windows

URL: http://oracle.com/technology/xe (http://oracle.com/technology/xe)

Larry Ellison drew even more attention to himself in October last year when Oracle announced a free version of its flagship database. The venerable tier-1 enterprise database now has a watered-down sibling. While Oracle XE is built from the same code base as the enterprise versions, for now it has the common scalability restrictions and is for 32-bit systems only. Oracle is pitching XE to developers, DBAs who need a "free starter" for training, and ISVs who can embed the software in their own products. Oracle Database XE can be installed on higher-capacity servers, but will only use its designated resources. The software ships with a management interface to monitor database activity and manage users, storage, and memory. Oracle claims XE applications will run unmodified on the enterprise editions.