MongoDB Aggregation with Mongoose in a CRUD Application

Using NodeJS and Mongoose to Explain Aggregation

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Aggregation operations group values from multiple documents together and can perform a variety of operations on the grouped data to return a single result.

MongoDB, a NoSQL database, offers us this powerful feature. It allows users to process data records and return computed results.

Let’s explore how to use MongoDB’s aggregation framework with Mongoose (a MongoDB object modeling tool) for Node.js in the context of a CRUD (Create, Read, Update, Delete) application.

Before diving into the aggregation framework, ensure you have Node.js and MongoDB installed on your system. Then, create a new Node.js project and install Mongoose:

npm init -y
npm install mongoose

Connecting to MongoDB with Mongoose

Create a file named index.js and establish a connection to your MongoDB database using Mongoose:

const mongoose = require('mongoose');

mongoose.connect('mongodb://localhost:27017/myDatabase', {
  useNewUrlParser: true,
  useUnifiedTopology: true,
})
.then(() => console.log('Connected to MongoDB...'))
.catch((err) => console.error('Could not connect to MongoDB:', err));