H2 is an SQL database engine written in Java that implements the JDBC API. Embedded, server, and clustering modes are available. A browser based console application is included. The database has strong security features. Disk based and in-memory databases and tables are supported.

Changes

Row level locking is now enabled when using MVCC (multi version concurrency). Multiple processes can now access the same database. The SHOW SQL statement is now supported. The linked table can now share a connection, and can be read-only, temporary, and point to different schemas. The storage re-use algorithm and the hash calculation for byte arrays are faster.

URL: H2 Database Engine