duckdb-hstore

April 9, 2026 · View on GitHub

This extension provides support for reading data from PostgreSQL hstore columns in DuckDB.

Installation

For the moment, you'll need to download the version for your system from the latest build run, unzip it, and then load it via

LOAD '/path/to/downloaded/hstore.duckdb_extension';

Retrieves the value associated with a given key from an hstore string. Returns NULL if the key is not found or if the value is NULL.

SELECT hstore_get('a=>b, c=>d', 'a');
-- b

SELECT hstore_get('a=>NULL, c=>d', 'a');
-- NULL

SELECT hstore_get('a=>b, c=>d', 'missing');
-- NULL

Converts an hstore string to a JSON object. NULL values in hstore become JSON null.

SELECT hstore_to_json('a=>1, b=>null');
-- {"a": "1", "b": null}

SELECT hstore_to_json('"a key"=>1, b=>2');
-- {"a key": "1", "b": "2"}

Returns JSON type.

make

The extension will be built at ./build/release/extension/hstore/hstore.duckdb_extension.

INSTALL hstore FROM '/build/release/extension/hstore/hstore.duckdb_extension';
LOAD hstore;

make test