H2 Database Engine 1.0/2007-08-02

H2 Database Engine is a free SQL database engine writen in Java.
JDBC and ODBC APIs are supported. Embedded and server modes are available. A Web console application is included. Clustering is supported.H2 Database Engine is a web based java database engine.
Main features:
Fast database engine
- Free, source code is included
- Supports standard SQL
- Written in Java
- Disk based or in-memory databases
- Browser base Console application
- JDBC API
- Limited ODBC support
- Embedded and client/server (network) mode
- High availablility support (clustering / failover)
- Wide range of data types including large objects (BLOB/CLOB)
- Strong security features (SSL, users, roles, encrypted files)
- Multiple connections, table level locking
- Cost based optimizer, using a genetic algorithm for complex queries
- Transaction support (serializable transaction isolation)
- Zero-administration, automatic recovery
- Large resultset, external sorting
- Scrollable and updatable resultset support
- Read only views and inline views
- Inner and outer joins, subqueries
- Many functions already built-in
- Triggers and Java functions / stored procedures
- Referential integrity / foreign key constraints with cascade, check constraints
- Multiple schema support
- Compatibility modes for HSQLDB, MySQL and PostgreSQL
- Sequence and autoincrement columns
- Well tested (high code coverage, randomized stress tests)
- Small footprint (smaller than 1 MB)
- Uses a small number of database files
- Can be compiled to native code using GCJ
- Primary keys, multiple index types (b-tree, linear hash, tree, hash)
- ORDER BY, GROUP BY, HAVING, UNION, LIMIT
- Information Schema
- Multiple connections
- Collation support
- EXPLAIN PLAN support
- The database can generate SQL script files
- Support for linked tables, and a built-in virtual range table
- Automatic re-compilation of prepared statements
- Sophisticated trace options
- Low memory requirements
- Easy to understand exception messages
- Standard handling of NULL values
- Multilanguage console application (at this time, English and German)
Currently, this is not traditional GPL software, but the source code is included. It is free for private and commercial use.
Enhancements:
- H2 now supports the PostgreSQL network protocol, and can be accessed using the PostgreSQL ODBC driver.
- Regular expressions are now supported.
- The per session undo log and referential integrity can be disabled.
- Default settings have been changed to save memory. NOT, boolean columns, and certain joins are optimized now.
- Part of the documentation has been translated to Japanese.