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Database connectors issue query requests to a backing data source.

A connector instance should expose a query(query) method that returns a Promise. The query argument is an object that may include the following properties:

  • sql: The SQL query to evaluate.
  • type: The query format type, such as "exec" (no return value), "arrow", and "json".
  • Any additional connector-specific options.

Once instantiated, register a connector with the coordinator using the coordinator.databaseConnector() method.



Create a new Web Socket connector to a DuckDB data server at the given uri (default "ws://localhost:3000/").



Create a new HTTP rest connector to a DuckDB data server at the given uri (default "http://localhost:3000/").



Create a new DuckDB-WASM connector with the given options. This method will instantiate a new DuckDB instance in-browser using Web Assembly. If no existing DuckDB-WASM instance is provided as an option, a new instance is created lazily upon first access.

The supported options are:

  • duckdb: An existing DuckDB-WASM instance to query. If unspecified, a new instance is created.
  • connection: An existing connection to a DuckDB-WASM instance to use. If unspecified, a new connection is created.
  • log: A Boolean flag (default false) that indicates if DuckDB-WASM logs should be written to the browser console. This option is ignored when an existing duckdb instance option is provided.