H2 is a relational database management system written in Java. It can be embedded in Java applications or run in the client-server mode. The software is available under a Free Software license, the Mozilla Public License.
Contents |
Main Features
A subset of the SQL (Structured Query Language) standard is supported. The main programming APIs are SQL and JDBC, however the database also provides an experimental ODBC driver. It is possible to create both in-memory tables, as well as disk-based tables. Tables can be persistent or temporary. Index types are hash table and tree for in-memory tables, and b-tree and linear hash index for disk-based tables. All data manipulation operations are transactional. Table level locking is implemented. The 2-phase commit protocol is supported as well, but no standard API for distributed transactions is implemented. The security features of the database are: role based access rights, encryption of the password using SHA-256 and data using the AES or the Tiny Encryption Algorithm, XTEA. The cryptographic features are available as functions inside the database as well. SSL / TLS connections are supported in the client-server mode, as well as when using the console application. A simple form of high availability is implemented: when used in the client-server mode, the database engine supports hot failover (this is commonly known as clustering). However, the clustering mode must be enabled manually after a failure.
Utilities
An embedded web server and a browser based console application are included.
History
The development of the H2 database engine started in May 2004, but it was first published in December 2005. The database engine is written by Thomas Mueller. He also developed the Java database engine Hypersonic SQL [1]. In 2001, the Hypersonic SQL was stopped, and the HSQLDB Group was formed to continued to work on the Hypersonic SQL code. The name H2 stands for Hypersonic 2, however H2 does not share any code with Hypersonic SQL or HSQLDB. H2 is built from scratch.
External links
|
|
|
|---|---|
| Database models · Database normalization · Database storage · Distributed DBMS · Referential integrity · Relational algebra · Relational calculus · Relational database · Relational DBMS · Relational model · Transaction processing | |
| Concepts | Database · ACID · Null · Candidate key · Foreign key · Primary key · Superkey · Surrogate key |
| Objects | Trigger · View · Table · Cursor · Log · Transaction · Index · Stored procedure · Partition |
| SQL | Select · Insert · Update · Merge · Delete · Join · Union · Create · Drop · Begin work · Commit · Rollback · Truncate · Alter |
| Implementations | Relational · Flat file · Deductive · Dimensional · Hierarchical · Network · Document-oriented · Object-oriented · Object-relational · Temporal · XML data stores |
| Components | Concurrency control · Query language · Query optimizer · Query plan · ODBC · JDBC |
| Database products: Object-oriented (comparison) · Relational (comparison) · Document-oriented | |
