Mongoose

• An elegant mongodb object modeling for node.js.
• First, ensure MongoDB and Node.js are installed.

MongoDB (As said by ChatGpt)

• MongoDB is a popular NoSQL database that stores data in flexible, JSON-like documents
• Instead of using tables and rows as in traditional relational databases, MongoDB uses collections and documents
• Key features:
  • Document-oriented: Data is stored in flexible JSON-like documents
  • Scalable: Supports horizontal scaling through sharding
  • High Performance: Provides high-speed access to data with indexing
  • Free and open-source
  • Supports rich queries, aggregation, and full-text search

Quick Start

• Install mongoose from the command line:

npm install mongoose --save

• To start mongoose and connect to MongoDB

// getting-started.js
const mongoose = require("mongoose");

main().catch((err) => console.log(err));

async function main() {
  await mongoose.connect("mongodb://127.0.0.1:27017/test");

  // use `await mongoose.connect('mongodb://user:password@127.0.0.1:27017/test');` if your database has auth enabled
}

• Within Mongoose, everything is derived from schema:

const kittySchema = new mongoose.Schema({
  name: String,
});

• Next, the schema need to be compiled into a Model.

const Kitten = mongoose.model("Kitten", kittySchema);

• A model is any class that documents are constructed in.
• To create a document:

const silence = new Kitten({ name: "Silence" });
console.log(silence.name); // 'Silence'

• Methods can be added to the methods property of a schema to be exposed on each document instance:

// NOTE: methods must be added to the schema before compiling it with mongoose.model()
kittySchema.methods.speak = function speak() {
  const greeting = this.name
    ? "Meow name is " + this.name
    : "I don't have a name";
  console.log(greeting);
};

const Kitten = mongoose.model("Kitten", kittySchema);

const fluffy = new Kitten({ name: "fluffy" });
fluffy.speak(); // "Meow name is fluffy"

• Documents can be saved to the database using the save method.

await fluffy.save();
fluffy.speak();

• All the documents of that model can be found through the model:

const kittens = await Kitten.find();
console.log(kittens);

• To query models, Mongoose supports MongoDBs querying syntax:

await Kitten.find({ name: /^fluff/ });