HSQLDB (HyperSQL DataBase) is the leading SQL relational database engine written in Java. It offers a small, fast multithreaded and transactional database engine with in-memory and disk-based tables and supports embedded and server modes. It includes a powerful command line SQL tool and simple GUI query tools.

For more information see http://hsqldb.org/

To make the driver accessible to JDBC and ActiveRecord code running in JRuby :

require 'jdbc/hsqldb'
Jdbc::HSQLDB.load_driver

For backwards compatibility with older (<= 1.8.1.3) versions of the gem use :

require 'jdbc/hsqldb'
Jdbc::HSQLDB.load_driver(:require) if Jdbc::HSQLDB.respond_to?(:load_driver)

Copyright (c) 2013 The JRuby Team.

HSQLDB is completely free to use and distribute under a license based on the standard BSD license and fully compatible with all major open source licenses. see LICENSE.txt and http://hsqldb.org/web/hsqlLicense.html for more details.