Adding documents (add vs set) in Firebase - Hands-On Comparison

Adding Documents in Firebase: Using add() vs set()

📖 Scenario: You are building a simple app to store user profiles in Firebase Firestore. You want to learn how to add new user documents to a collection using two different methods: add() and set().This will help you understand how to create documents with automatic IDs and how to create or overwrite documents with specific IDs.

🎯 Goal: Build a Firebase Firestore setup where you first create a collection called users and add user documents using add() and set() methods correctly.

📋 What You'll Learn

Create a Firestore collection reference called usersRef pointing to the users collection

Add a new user document with automatic ID using add() with exact data

Create a user document with a specific ID using set() with exact data

Use correct Firestore syntax for both methods

💡 Why This Matters

🌍 Real World

Adding and managing user data in Firestore is common in apps like social networks, e-commerce, and content management systems.

💼 Career

Understanding Firestore document creation methods is essential for cloud developers working with Firebase backend services.

1

Create Firestore collection reference

Create a variable called usersRef that references the Firestore collection named users using firebase.firestore().collection('users').

Firebase

# Your code here

Need a hint?

Use firebase.firestore().collection('users') to get the collection reference.

2

Add a user document with automatic ID using add()

Use the add() method on usersRef to add a new user document with these exact fields: { name: 'Alice', age: 30 }.

Firebase

const usersRef = firebase.firestore().collection('users');
// Your code here

Need a hint?

Call usersRef.add() with the user data object.

3

Create a user document with a specific ID using set()

Create a document reference called bobDoc inside usersRef with the ID 'bob123' using usersRef.doc('bob123'). Then use set() on bobDoc to set the user data { name: 'Bob', age: 25 }.

Firebase

const usersRef = firebase.firestore().collection('users');
usersRef.add({ name: 'Alice', age: 30 });
// Your code here

Need a hint?

Use usersRef.doc('bob123') to get the document reference, then call set() with the data.

4

Complete Firestore document additions

Ensure the full code includes the usersRef collection reference, the add() call for Alice, and the set() call for Bob with ID 'bob123'.

Firebase

const usersRef = firebase.firestore().collection('users');
usersRef.add({ name: 'Alice', age: 30 });
const bobDoc = usersRef.doc('bob123');
bobDoc.set({ name: 'Bob', age: 25 });
// Your code here

Need a hint?

Review your code to confirm all parts are included.