Change streams in MongoDB

🔹 What is Watching? “Watching” in MongoDB refers to Change Streams . It allows your application to listen to real-time changes in the database Simple: Whenever data changes → you get notified instantly 🔹 What Changes Can You Watch? Insert (new document) Update Delete Replace  Example Idea If a new user is added: Your app can immediately: Send notification Update UI Trigger some logic 🔹 How it Works You “watch” a collection: db.users.watch() Then MongoDB sends updates whenever something changes 🔹 Output Example You receive events like: operationType: "insert" operationType: "update" 🔹 Where It is Used Real-time apps (chat apps 💬) Notifications Live dashboards Event-driven systems 🔹 Requirements Works on replica sets or sharded clusters Not available on standalone servers Advantages Real-time updates No need for polling Efficient and event-based