hsqldb - 100% Free and Fast Java Database

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Features Summary

• 100% Java
• A full RDBMS (Relational Database Management System), with the Object capabilities of Java
• Switchable source code to support JDK 1.1.x, 1.2.x, 1.3.x, 1.4.x and above
• Super fast startup and SELECT, INSERT, DELETE and UPDATE operations
• Standard SQL (Structured Query Language) syntax
• Inner and outer joins, SELECT queries as correlations in joins
• Scalar (single value) SELECTS, correlated subqueries including IN, EXISTS, ANY, ALL
• Views, Temp tables and sequences
• Primary key, unique and check constraints on single or multiple columns
• Indexes on single or multiple columns
• ORDER BY, GROUP BY and HAVING
• COUNT, SUM, MIN, MAX, AVG and statistical aggregate functions (also in expressions and function arguments)
• 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
• Referential Integrity (foreign keys) with full cascading options (delete, update, set null, set default)
• Multiple schemata per database
• Java stored procedures and functions
• Triggers
• Database security with passwords, user rights and roles with GRANT and REVOKE
• Extensive set of ALTER TABLE commands allowing change of column type
• In-memory tables for fastest operation
• Disk based tables for large data sets
• Text tables with external file data sources such as CSV files
• In-memory (like applets), 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
• Disk tables (CACHED TABLE) up to 8GB and text tables up to 2GB each
• Size of each string and binary data item only limited by memory
• Full support for PreparedStatement objects to speed up query processing
• 95% JDBC interface support with batch statement and scrollable ResultSet functionality
• All JDBC 1 data types supported, plus 'Object' , Boolean, Blob and Clob
• Full JDBC 2 DatabaseMetaData and ResultSetMetaData support
• Database dump as SQL script with or without data
• Powerful and compact java command line and GUI tools for database management