hsqldb Database Engine

This version follows the SQL:2008 Standard and supports more SQL features than other major open source RDBMS. Advanced data types, such as datetime INTERVAL and ARRAY types, together with query features such as FULL and LATERAL joins are supported. Full support was added for procedural SQL, including SQL/PSM functions, procedures and triggers, together with more extensive suport for Java routines. A dedicated high-performance LOB store makes this version ideal for high volume content managment systems.

A bug with logging deletes and updates from tables without primary keys was fixed. Conversions from BIGINT to SAMMLINT and TYNYINT are now allowed. An issue with null values in calls to ResultSet methods with a Calendar argument was fixed. INSERT INTO [T] SELECT (....) is now allowed where no column list is specified. The scripting of CHECK constraints with NOT NULL and IS NULL was corrected. An NPE error when functions are in subqueries was fixed. Support for various set functions was added, and issues with logging DELETE statements for tables with multi-key primary keys were fixed.

Code needed for embedding into OpenOffice.org was
added. A rewritten implementation of Cache is
included. Reuse of file space when rows are
deleted was improved. This is aimed primarily at
JBoss usage, which involves a million or more
insert/delete/update operations per day and
results in much smaller .data files over time.
Performance has been improved in certain areas,
such as recovery after an abnormal termination.
Enhancements were made to DatabaseManagerSwing.

This version features improved conformance to SQL
standards by supporting the UNDEFINED state for the
BOOLEAN type. This change has an effect in query conditions
and check constraints when values include a NULL.

This release features newly written code for system tables,
multiple database support, better query processing, and
more advanced SQL keywords, etc.