HSQLDB – Java database

Hyper Structured Query Language Database (HSQLDB) is an SQL relational database management system written in Java. It has a JDBC driver conforming to ANSI SQL:2008 and supports a rich subset of SQL-92 (BNF tree format) plus SQL:1999 and SQL:2003 enhancements. It is a small, fast, multithreaded engine and server with in-memory and disk based tables, LOBs, transaction isolation, encryption and ACID.

HSQLDB offers a small, fast database engine that offers both in-memory and disk-based tables.

There are embedded and server modes available. Additionally, this package 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.

HSQLDB is used as a database and persistence engine in many open source software projects, such as OpenOffice.org, Kurlo, JBoss, Spring Framework as well as in commercial products, such as Mathematica and Hedgehog.

Features include:

JAVA

• 100% Java.
• Support JDK 1.1.x, 1.2.x, 1.3.x, 1.4.x.
• Extensive JDBC interface support with batch statement and scrollable ResultSet functionality.
• Updatable, insertable ResultSet functionality.
• Full JDBC DatabaseMetaData and ResultSetMetaData support.
• Java stored procedures and functions.
• Full support for PreparedStatement objects to speed up query processing.

SQL

• Relational Database Management System, which can store Serializable Java objects.
• Very extensive support for SQL:2008 Standard syntax, including most optional features.
• Supports all base data types of the SQL Standard, including BINARY, BIT, BOOLEAN, date-time, INTERVAL, BLOB, CLOB.
• Supports user-defined DOMAIN types, including type constraints.
• Fast SELECT, INSERT, DELETE, UPDATE and MERGE operations.
• INNER, LEFT OUTER, RIGHT OUTER and FULL joins.
• NATURAL, USING and UNION joins.
• UNION, EXCEPT, INTERSECT, including use of parentheses, limits and offsets, ALL, DISTINCT and CORRESPONDING keywords.
• Scalar (single value) SELECTS, row and correlated subqueries including IN, EXISTS, ANY, ALL
• Views, Temp tables and sequences.
• Updatable views.
• Primary key, unique and check constraints on single or multiple columns.
• Referential Integrity (foreign keys) on multiple columns with full cascading options (delete, update, set null, set default).
• ORDER BY, GROUP BY and HAVING.
• COUNT, SUM, MIN, MAX, AVG and statistical aggregate functions.
• Full support for SQL expressions such as CASE .. WHEN .. ELSE .. , NULLIF etc.
• SQL standard autoincrement column support plus sequences.
• Transaction COMMIT, ROLLBACK and SAVEPOINT support.
• Multiple schemata per database.
• Triggers, implemented as Java classes, or as SQL statements.
• Database security with passwords, user rights and roles with GRANT and REVOKE.
• Extensive set of ALTER TABLE commands, including change of table column type.
• SQL stored procedures and functions.

Persistence

• In-memory tables for fastest operation.
• Disk based tables for large data sets.
• Text tables with external file data sources such as CSV files.
• Disk tables (CACHED TABLE) up to 16GB and text tables up to 2GB each.
• CLOB and BLOB storage up to 16 TB.
• Size of each string or binary item only limited by memory.
• Database dump as SQL script with or without data.

Deployment

• Embedded (into Java applications) and Client-Server operating modes.
• Three client server protocols: HSQL, HTTP and HSQL-BER – can run as an HTTP web server – all with SSL option.
• Can be used in applets, read-only media (CD), inside jars, webstart and embedded applications.
• Multiple databases per JVM.
• ODBC support.

Utilities

• Powerful and compact java command line and GUI tools for database management.
• Transfer tool for conversion of databases to / from other popular database management systems.

Website: hsqldb.org
Support: FAQ
Developer: The hsql Development Group
License: BSD License

HSQLDB is written in Java. Learn Java with our recommended free books and free tutorials.

Return to Relational Databases

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