Holt-backed metadata indexes for fast DuckDB file discovery
Maintainer(s):
feichai0017
Installing and Loading
INSTALL holtfs FROM community;
LOAD holtfs;
Example
-- Build a persistent Holt metadata index for a local lakehouse path.
SELECT *
FROM holtfs_index('/data/lake/table',
mode := 'persistent',
index_path := '/var/cache/duckdb/table.holt');
-- Reuse the index for repeated file discovery and partition listing.
SELECT entry_type, path, version
FROM holt_files('/var/cache/duckdb/table.holt',
mode := 'persistent',
prefix := '/data/lake/table/date=2026-05-22/',
delimiter := '/');
About holtfs
HoltFS exposes Holt-backed file metadata indexes inside DuckDB. It is intended for repeated file-discovery and partition-planning workloads where walking a local filesystem or object-store namespace is more expensive than querying a cached metadata index.
The preview release includes persistent and in-memory indexes, keys-only namespace scans, delimiter-style listing, manifest freshness checks, known-prefix refresh, and exact validation against local file size and modification time.
For usage and benchmark notes, see the duckdb-holtfs documentation.
Added Functions
| function_name | function_type | description | comment | examples |
|---|---|---|---|---|
| holt_files | table | NULL | NULL | |
| holtfs_index | table | NULL | NULL | |
| holtfs_refresh | table | NULL | NULL | |
| holtfs_status | table | NULL | NULL | |
| holtfs_validate | table | NULL | NULL | |
| holtfs_version | scalar | NULL | NULL |
Overloaded Functions
This extension does not add any function overloads.
Added Types
This extension does not add any types.
Added Settings
This extension does not add any settings.