One$DB
One$DB is a version of Daffodil DB , a J2EE-certified, JDBC 3.0 and SQL-99 compliant Java database. It is available in both Network and Embedded editions and has been designed to handle complex computing environments that demand a robust, scalable and feature-rich RDBMS that can operate across platforms.
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License
GNU Library or Lesser General Public License (LGPL)