[ Thanks to LT for this link. ]
“H2 (Hypersonic 2) is a relational database management system
based on Java and supports a subset of the SQL standard. Although
it also supports using the PostgreSQL ODBC driver by acting like a
PostgreSQL server, its main programming APIs are SQL and JDBC. H2
can run in the client-server mode or can be embedded in Java
applications. It runs fast and has a very small footprint having
only around 1 MB jar file size. With H2, users can create both
in-memory tables, as well as disk-based tables. Its security
features include role-based access rights and encryption of the
password using SHA-256 and data using the AES or the Tiny
Encryption Algorithm, XTEA. It provides protection against SQL
injection by enforcing the use of parameterized statements. H2
offers embedded web server with a browser-based console
application. It also has command line tools to start and stop a
server and for backing up and restoring databases. “