HSQLDB is the leading SQL relational database engine written in Java. HSQLDB has a JDBC driver and supports a rich subset of ANSI-92 SQL (BNF tree format) plus SQL 99 and 2003 enhancements. HSQLDB offers a small (less than 100k in one version), fast database engine which offers both in-memory and disk-based tables. Embedded and server modes are available. Additionally, it includes tools such as a minimal web server, in-memory query and management tools (can be run as applets) and a number of demonstration examples.
The product is currently being used as a database and persistence engine in many Open Source Software projects and even in commercial projects and products. In it's current version it is extremely stable and reliable. HSQLDB is best known for its small size, ability to execute completely in memory and its speed.
This feature-packed software is completely free under our licenses , based on the standard BSD license. Yes, that's right, completely free of cost or onerous restrictions and fully compatible with all major open source licenses. Java source code and extensive documentation always included.
Berkeley DB JE is a high performance, transactional storage engine written entirely in Java. Like the highly successful Berkeley DB product, Berkeley DB JE executes in the address space of the application, without the overhead of client/server communication. It stores data in the application's native format, so no runtime data translation is required. Berkeley DB JE supports full ACID transactions and recovery. It provides an easy-to-use interface, allowing programmers to store and retrieve information quickly, simply and reliably.
Berkeley DB JE was designed from the ground up in Java. It takes full advantage of the Java environment. The Berkeley DB JE API provides a Java Collections-style interface, as well as a programmatic interface similar to the Berkeley DB API. The architecture of Berkeley DB JE supports high performance and concurrency for both read-intensive and write-intensive workloads.
Berkeley DB JE is different from all other Java databases available today. Berkeley DB JE is not a relational engine built in Java. It is a Berkeley DB-style embedded store, with an interface designed for programmers, not DBAs. Berkeley DB JE's architecture employs a log-based, no-overwrite storage system, enabling high concurrency and speed while providing ACID transactions and record-level locking. Berkeley DB JE efficiently caches most commonly used data in memory, without exceeding application-specified limits. In this way Berkeley DB JE works with an application to use available JVM resources while providing access to very large data sets.
The Berkeley DB JE architecture provides an underlying storage layer for any Java application requiring high performance, transactional integrity and recoverability.
IBM Cloudscape is a pure, open source-based Java relational database management system that can be embedded in Java programs and used for online transaction processing (OLTP). A platform-independent, small-footprint (2MB) database, Cloudscape integrates tightly with any Java-based solution.