Why Realtime Database differs from Firestore in Firebase - Why It Works

Introduction

Realtime Database and Firestore are two ways to store and sync data in Firebase. They solve the problem of keeping app data updated across users and devices but do it differently.

When you want simple, low-latency syncing of data in a tree-like structure for small apps.

When you need complex queries and better scalability for large apps.

When offline support with automatic syncing is important.

When you want to structure data in collections and documents instead of a big JSON tree.

When you want strong consistency and real-time updates with flexible security rules.

Commands

This command fetches the root data from the Realtime Database to see its current state.

Terminal

firebase database:get /

Expected Output

{

  "users": {

    "user1": {

      "name": "Alice",

      "age": 30

    }

  }

}

This command fetches the document 'user1' from the 'users' collection in Firestore to compare data structure.

Terminal

firebase firestore:documents get users/user1

Expected Output

{

  "name": "Alice",

  "age": 30

}

Key Concept

If you remember nothing else, remember: Realtime Database stores data as one big JSON tree, while Firestore stores data in collections and documents for better structure and querying.

Common Mistakes

Trying to use complex queries in Realtime Database like in Firestore.

Realtime Database supports only simple queries and can become slow or complicated with large data.

Use Firestore when you need advanced querying and better data structure.

Assuming offline support works the same in both databases.

Firestore has built-in offline support with automatic syncing, while Realtime Database requires manual handling.

Choose Firestore for easier offline data handling.

Summary

Realtime Database stores data as a large JSON tree, Firestore uses collections and documents.

Firestore supports more complex queries and scales better for large apps.

Offline support and syncing are easier with Firestore.