Node.js MongoDB Insert

In MongoDB, inserting data into collections is a fundamental operation. Using Node.js, you can efficiently insert one or multiple documents into a collection. This guide covers various methods to perform insert operations with the mongodb driver.

 

Key Features of Insert Operations

1. Flexibility: Insert a single document or multiple documents in one operation.
2. Auto-Generated _id: Each document gets a unique _id field if not provided.
3. Batch Insertion: Multiple documents can be inserted simultaneously for efficiency.

 

Step 1 Prerequisites

Ensure MongoDB is installed and running, and the mongodb package is installed in your Node.js project.

npm install mongodb

Step 2 Insert a Single Document

The insertOne method allows you to add a single document to a collection.

Example Code

const { MongoClient } = require('mongodb');

// Connection URL and Database Name
const url = 'mongodb://127.0.0.1:27017';
const dbName = 'mydatabase';

async function insertSingleDocument() {
  const client = new MongoClient(url);

  try {
    await client.connect();
    const db = client.db(dbName);
    const collection = db.collection('users');

    // Insert a single document
    const result = await collection.insertOne({ name: 'Alice', age: 28 });
    console.log('Document inserted:', result.insertedId);
  } finally {
    await client.close();
  }
}

insertSingleDocument().catch(console.error);

Output:

Document inserted: 61b0fcab12c5ae23f89e7a12

Step 3 Insert Multiple Documents

The insertMany method is used to insert multiple documents at once.

Example Code

async function insertMultipleDocuments() {
  const client = new MongoClient(url);

  try {
    await client.connect();
    const db = client.db(dbName);
    const collection = db.collection('users');

    // Insert multiple documents
    const documents = [
      { name: 'Bob', age: 32 },
      { name: 'Charlie', age: 45 },
    ];
    const result = await collection.insertMany(documents);
    console.log(`${result.insertedCount} documents inserted`);
  } finally {
    await client.close();
  }
}

insertMultipleDocuments().catch(console.error);

Output:

2 documents inserted

Step 4 Verify Inserted Data

• Start the MongoDB shell or connect using a GUI like MongoDB Compass.
• Switch to your database:

use mydatabase

• Query the collection to view the inserted documents:

db.users.find()

Step 5 Handle Duplicate Keys

MongoDB ensures each document has a unique _id. Attempting to insert a document with a duplicate _id will result in an error.

Example Code

async function handleDuplicateKey() {
  const client = new MongoClient(url);

  try {
    await client.connect();
    const db = client.db(dbName);
    const collection = db.collection('users');

    // Insert a document with a custom _id
    const result = await collection.insertOne({ _id: 1, name: 'David', age: 29 });
    console.log('Document inserted:', result.insertedId);

    // Attempt to insert a document with the same _id
    await collection.insertOne({ _id: 1, name: 'Emma', age: 34 });
  } catch (error) {
    console.error('Error occurred:', error.message);
  } finally {
    await client.close();
  }
}

handleDuplicateKey().catch(console.error);

Output:

Document inserted: 1  
Error occurred: E11000 duplicate key error collection: mydatabase.users index: _id_ dup key: { _id: 1 }

 

Summary

MongoDB's insertOne and insertMany methods in Node.js provide efficient ways to add data to collections. These methods offer flexibility, allowing single or batch inserts, and handle errors like duplicate keys gracefully. Following this guide ensures seamless data insertion in your Node.js applications.