What Is New in HSQLDB 2.4
HSQLDB 2.4 delivers a substantial update focused on SQL standards compliance, performance enhancements, and expanded functionality. This release builds on the foundation of previous versions with critical fixes and new capabilities for developers.
| Category | Key Changes |
|---|---|
| New Features | Support for SQL:2016 functions, new built-in functions, enhanced data types. |
| Improvements | Better optimizer performance, faster text table processing, improved memory usage. |
| Bug Fixes | Numerous corrections to SQL standard compliance, indexing, and transaction handling. |
| Deprecated Features | Some older, non-standard syntax has been deprecated in favor of standard SQL. |
What SQL standard enhancements are included?
HSQLDB 2.4 significantly boosts its adherence to the SQL:2016 standard. This includes adding support for new built-in functions and improving existing ones to match standard behavior.
You get functions like LISTAGG for string aggregation and TRIM_ARRAY. In practice, this
means your SQL code becomes more portable and aligns with what other major databases expect.
How is text table processing faster?
The engine for reading and writing TEXT tables has been overhauled for better performance. This is a big deal if you use HSQLDB for importing and exporting large CSV-like files.
The internal parsing is more efficient, reducing memory overhead and speeding up data loads. You'll notice this most when working with large text data sets.
What optimizer improvements were made?
The query optimizer received targeted tweaks to handle specific SQL patterns more effectively. This matters because it can lead to better execution plans without any changes to your application code.
These changes help with join ordering and condition evaluation, which can cut down query execution time for complex queries.
FAQ
Is LISTAGG function now supported?
Yes, HSQLDB 2.4 adds support for the SQL:2016
LISTAGG aggregate function, allowing for easy string concatenation within groups.
Should I expect any breaking changes?
While many changes are additive, some older,
non-standard syntax has been deprecated. Check the release notes for specific keywords that are now discouraged.
Does this release improve memory usage?
Yes, several internal optimizations, particularly in
text table processing and caching, result in more efficient memory utilization during operations.
Are there any new data types?
The focus was on enhancing existing type handling and
compliance rather than introducing entirely new types, though support for standard type conversions was
improved.
Has transaction handling been fixed?
Several bugs related to transaction isolation and
rollback behavior were addressed, making transaction processing more reliable.