[Node-DuckDB API](./node-duckdb.md) > [Connection](./node-duckdb.connection.md) ## Connection class Represents a DuckDB connection. Signature: ```typescript export declare class Connection ``` ## Remarks A single db instance can have multiple connections. Having more than one connection instance is required when executing concurrent queries. ## Constructors | Constructor | Modifiers | Description | | ------------------------------------------------------------------ | --------- | ----------------------- | | [(constructor)(duckdb)](./node-duckdb.connection._constructor_.md) | | Connection constructor. | ## Properties | Property | Modifiers | Type | Description | | ------------------------------------------------ | --------- | ------- | ---------------------------------------------------------- | | [isClosed](./node-duckdb.connection.isclosed.md) | | boolean | If the connection is closed returns true, otherwise false. | ## Methods | Method | Modifiers | Description | | -------------------------------------------------------------------------------- | --------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [close()](./node-duckdb.connection.close.md) | | Close the connection (also closes all [Readable](https://nodejs.org/api/stream.html#stream_class_stream_readable) or [ResultIterator](./node-duckdb.resultiterator.md) objects associated with this connection). | | [execute(command, options)](./node-duckdb.connection.execute.md) | | Asynchronously executes the query and returns a [Readable stream](https://nodejs.org/api/stream.html#stream_class_stream_readable) that wraps the result set. | | [executeIterator(command, options)](./node-duckdb.connection.executeiterator.md) | | Asynchronously executes the query and returns an iterator that points to the first result in the result set. |