Small database being backed by both Sun and IBM
As per Sun and IBM, the IT industry is moving towards a mixed model and commercial tools are being built on top of open source frameworks and both the companies are supplying similar small footprint pure Java open source database. IBM refers it to as Cloudscape and ships along with the Websphere application server whereas Sun refers it to as Java DB and ships it along with the Java Enterprise System and Solaris Enterprise System. Both Java DB and Cloudscape are full implementations of the apache software foundation's Derby Project.
Though the size is quite small – only about 2Mbytes, Java DB and Cloudscape have standard relational database functions like triggers, multi user support and failure recovery. Java DB is used as an embedded application whereas Cloudscape is used for offering SQL functionality within applications developed under Eclipse. The small size ensures that it can be distributed within browser based applications requiring local data store.