2026-07-22

Announcing DuckDB 1.5.5

The DuckDB team

In this blog post, we highlight a few important fixes in DuckDB v1.5.5, the sixth patch release in DuckDB’s 1.5 (Variegata) line. The release ships bugfixes, performance improvements and security patches. You can find the full release notes on GitHub.

To install the new version, please visit the installation page.

Here are the most important fixes from the DuckDB v1.5.5 release, organized by category:

Correctness

#23693 – Fix swapped min/max for multi-row-group 128-bit DECIMAL in RETURN_STATS

Crashes and Internal Errors

#23517 – Fix min/max aggregate stats when row groups are filtered, which caused a crash
#23351 – Fix deadlock in TemporaryMemoryManager
#23566 – Fix C API scalar bind subquery crash
#23757 – Fix segfault in external hash aggregate when radix bits grow after going external
#23861 – Fix concurrent ALTER and INSERT crash
#23593 – Fixed unsafe iteration when parent is NULL in string cast
#23341 – Add additional guards to DICT_FSST to prevent exception during compression with small block sizes

Generic Bugfixes

#23458 – Fix false RLE corruption error
#23534 – Fix Arrow type extension bugs
#23507 – Fix ALTER TABLE ADD COLUMN IF NOT EXISTS ... DEFAULT regression
#23714 – Fix DROP COLUMN corrupting per-column metadata block bookkeeping
#23808 – Fix ALTER dependency preservation in DependencyManager
#23790 – TryLookupEntry now uses default schema as fallback
#23354 – Prevent NULL MAP keys in MultiFileReader due to missing default values
#23803 – Fix malformed JSON when rendering via duckbox
#23879 – Fix reset of empty_range in the TIMESTAMP range() table function
#23479 – Fix eviction node memory leak when using external files

Performance

#23483 – Enable ALP and ALP_RD for storage version v1.5.0 and up with smaller block sizes

Miscellaneous

#21293 – Add support for duckdb:// URI scheme in ADBC
#23230 – Support the ADBC Statistics API
#23316 – Add request body length to HTTP logs
#23327 – Show transport errors in HTTP log
#23752 – Include extension header in libduckdb archives

Conclusion

This post was a short summary of the changes in v1.5.5. As usual, you can find the full release notes on GitHub. We would like to thank our contributors for providing detailed issue reports and patches. Stay tuned for future DuckDB releases, including v2.0.0 in the fall!