/**

* Basic MotherDuck connection and query examples using DuckDB Neo driver.

*

* Run: npm run basic

*/

import "dotenv/config";

import { DuckDBInstance } from "@duckdb/node-api";

const token = process.env.MOTHERDUCK_TOKEN;

const database = process.env.MOTHERDUCK_DATABASE || "my_db";

if (!token) {

console.error("Error: MOTHERDUCK_TOKEN environment variable is not set");

console.error("Copy .env.template to .env and add your token");

process.exit(1);

}

async function main() {

// Connect to MotherDuck using fromCache() to avoid reinitializing

// the MotherDuck extension on every connection. Unlike Python/R/JDBC,

// the Node.js client does NOT cache instances automatically.

console.log(`Connecting to MotherDuck database: ${database}...`);

const instance = await DuckDBInstance.fromCache(`md:${database}`, {

motherduck_token: token,

});

const connection = await instance.connect();

console.log("Connected!\n");

try {

// Example 1: Simple query

console.log("--- Example 1: Simple query ---");

const reader = await connection.runAndReadAll("SELECT 42 AS answer");

console.table(reader.getRowObjects());

console.log();

// Example 2: Create and query a table

console.log("--- Example 2: Create and query a table ---");

await connection.run(`

CREATE OR REPLACE TABLE example_users (

id INTEGER,

name VARCHAR,

email VARCHAR

)

`);

await connection.run(`

INSERT INTO example_users VALUES

(1, 'Alice', 'alice@example.com'),

(2, 'Bob', 'bob@example.com'),

(3, 'Charlie', 'charlie@example.com')

`);

const users = await connection.runAndReadAll("FROM example_users");

console.table(users.getRowObjects());

console.log();

// Example 3: Parameterized queries

console.log("--- Example 3: Parameterized query ---");

const prepared = await connection.prepare(

"SELECT * FROM example_users WHERE id = $1"

);

prepared.bindInteger(1, 2);

const userReader = await prepared.runAndReadAll();

console.table(userReader.getRowObjects());

console.log();

// Example 4: Aggregate query

console.log("--- Example 4: Aggregate query ---");

const countReader = await connection.runAndReadAll(`

SELECT COUNT(*) AS total_users FROM example_users

`);

console.table(countReader.getRowObjects());

console.log();

// Example 5: Query MotherDuck sample data

console.log("--- Example 5: Query sample data from MotherDuck ---");

const sampleReader = await connection.runAndReadAll(`

SELECT * FROM sample_data.nyc.taxi LIMIT 5

`);

console.log("NYC taxi sample (5 rows):");

console.table(sampleReader.getRowObjects());

console.log();

// Example 6: Multiple connections via cached instance

console.log("--- Example 6: Reuse cached instance for a second connection ---");

const instance2 = await DuckDBInstance.fromCache(`md:${database}`, {

motherduck_token: token,

});

const connection2 = await instance2.connect();

try {

const versionReader = await connection2.runAndReadAll(

"SELECT version() AS duckdb_version, current_database() AS db"

);

console.table(versionReader.getRowObjects());

} finally {

connection2.closeSync();

}

console.log();

} finally {

await connection.run("DROP TABLE IF EXISTS example_users");

connection.closeSync();

console.log("Done!");

}

}

main().catch(console.error);