Hasura DuckDB Connector

The Hasura DuckDB Connector allows for connecting to a DuckDB database or a MotherDuck hosted DuckDB database to give you an instant GraphQL API on top of your DuckDB data.

This connector is built using the Typescript Data Connector SDK and implements the Data Connector Spec.

• See the listing in the Hasura Hub
• Hasura V3 Documentation

Features

Below, you'll find a matrix of all supported features for the DuckDB connector:

Feature	Supported	Notes
Native Queries + Logical Models	❌
Simple Object Query	✅
Filter / Search	✅
Simple Aggregation	❌
Sort	✅
Paginate	✅
Table Relationships	✅
Views	❌
Distinct	❌
Remote Relationships	✅
Custom Fields	❌
Mutations	❌

Before you get Started

1. The DDN CLI and Docker installed
2. A supergraph
3. A subgraph
4. Have a MotherDuck hosted DuckDB database, or a persitent DuckDB database file — for supplying data to your API.

The steps below explain how to Initialize and configure a connector for local development. You can learn how to deploy a connector — after it's been configured — here.

Using the DuckDB connector

Step 1: Authenticate your CLI session

ddn auth login

Step 2: Configure the connector

Once you have an initialized supergraph and subgraph, run the initialization command in interactive mode while providing a name for the connector in the prompt:

ddn connector init duckdb -i

Step 2.1: Choose the hasura/duckdb option from the list

Step 2.2: Choose a port for the connector

The CLI will ask for a specific port to run the connector on. Choose a port that is not already in use or use the default suggested port.

Step 2.3: Provide the env var(s) for the connector

Name	Description
DUCKDB_URL	The connection string for the DuckDB database, or the file path to the DuckDB database file

You'll find the environment variables in the .env file and they will be in the format:

<SUBGRAPH_NAME>_<CONNECTOR_NAME>_<VARIABLE_NAME>

Here is an example of what your .env file might look like:

APP_DUCKDB_AUTHORIZATION_HEADER="Bearer SPHZWfL7P3Jdc9mDMF9ZNA=="
APP_DUCKDB_DUCKDB_URL="md:?motherduck_token=ey..."
APP_DUCKDB_HASURA_SERVICE_TOKEN_SECRET="SPHZWfL7P3Jdc9mDMF9ZNA=="
APP_DUCKDB_OTEL_EXPORTER_OTLP_TRACES_ENDPOINT="http://local.hasura.dev:4317"
APP_DUCKDB_OTEL_SERVICE_NAME="app_duckdb"
APP_DUCKDB_READ_URL="http://local.hasura.dev:7525"
APP_DUCKDB_WRITE_URL="http://local.hasura.dev:7525"

If you are attaching to a local DuckDB file, first make sure that the file is located inside the connector directory. For example, if you had a data.duckdb file you could place it at /app/connector/duckdb/data.duckdb. Files in the connector directory get mounted to /etc/connector/.

In this instance, you would set the DUCKDB_URL=/etc/connector/data.duckdb. Now your .env might look like this:

APP_DUCKDB_AUTHORIZATION_HEADER="Bearer SPHZWfL7P3Jdc9mDMF9ZNA=="
APP_DUCKDB_DUCKDB_URL="/etc/connector/data.duckdb"
APP_DUCKDB_HASURA_SERVICE_TOKEN_SECRET="SPHZWfL7P3Jdc9mDMF9ZNA=="
APP_DUCKDB_OTEL_EXPORTER_OTLP_TRACES_ENDPOINT="http://local.hasura.dev:4317"
APP_DUCKDB_OTEL_SERVICE_NAME="app_duckdb"
APP_DUCKDB_READ_URL="http://local.hasura.dev:7525"
APP_DUCKDB_WRITE_URL="http://local.hasura.dev:7525"

Your experience mounting files may vary, and while useful to explore a file locally, it's not recommended to attempt to deploy a connector using a locally mounted file.

Step 3: Introspect the connector

Introspecting the connector will generate a config.json file and a duckdb.hml file.

ddn connector introspect duckdb

Step 4: Add your resources

You can add the models, commands, and relationships to your API by tracking them which generates the HML files.

ddn connector-link add-resources duckdb

Documentation

View the full documentation for the DuckDB connector here.

Contributing

Check out our contributing guide for more details.

License

The DuckDB connector is available under the Apache License 2.0.