MongoDb example

The MERN stack is a popular web development stack that consists of MongoDB, Express, React, and Node.js. When working with the MERN stack, it's common to use MongoDB as the database. MongoDB is a NoSQL database that uses a document-oriented data model, which makes it a good fit for web applications that require flexible and scalable data storage.

Here are some examples of database operations you could include in a chapter on MongoDB:

1. Connecting to a MongoDB database:

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

// or as an es module:

// import { MongoClient } from 'mongodb'

// Connection URL

const url = 'mongodb://localhost:27017';

const client = new MongoClient(url);

// Database Name

const dbName = 'test';

async function main() {

  // Use connect method to connect to the server

  await client.connect();

  console.log('Connected successfully to server');

  const db = client.db(dbName);

  const collection = db.collection('device');

  // the following code examples can be pasted here...

  return 'done.';

}

main()

  .then(console.log)

  .catch(console.error)

  //.finally(() => client.close());

2. Inserting data into a collection:

const createResult = await collection.insertOne({ name: "John Doe",age: 35,});

console.log("Created documents =>", createResult);

3. Querying data from a collection:

const findResult = await collection.find({ name: "John Doe" }).toArray();

console.log('Found documents =>', findResult);

4. Updating data in a collection:

const updateResult = await collection.updateOne({ name: "John Doe" }, { $set: { age: 31 } });

console.log("Updated document", updateResult);

5. Deleting data from a collection:

const deleteResult = await collection.deleteOne({ name: "John Doe" });

console.log("Deleted document", deleteResult);

These are some basic examples of MongoDB operations that you could include in a chapter on the database. You can build upon these examples to cover more advanced topics, such as indexing, aggregation, and transaction management in MongoDB.