Why Firestore is Firebase's primary database - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to initialize Firestore in a Firebase app.

Firebase

const db = firebase.[1]();

Drag options to blanks, or click blank then click option'

Astorage

Bauth

Cfirestore

Ddatabase

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'database()' initializes the Realtime Database, not Firestore.

The firestore() method initializes Firestore, Firebase's primary database.

2fill in blank

medium

Complete the code to add a document to a Firestore collection.

Firebase

db.collection('users').[1]({ name: 'Alice', age: 30 });

Drag options to blanks, or click blank then click option'

Aadd

Bset

Cupdate

Dget

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'set' on a collection causes an error.

The add() method adds a new document with an auto-generated ID to the collection.

3fill in blank

hard

Fix the error in the code to get a document by ID from Firestore.

Firebase

db.collection('users').doc([1]).get().then(doc => { if (doc.exists) { console.log(doc.data()); } });

Drag options to blanks, or click blank then click option'

AdocId

BuserId

Cuser.id

D'userId'

Attempts:

3 left

💡 Hint

Common Mistakes

Passing variable names without quotes when they are not defined.

The document ID must be a string. Using quotes around 'userId' passes the ID correctly.

4fill in blank

hard

Fill both blanks to query Firestore for users older than 25 and order by age.

Firebase

db.collection('users').where('age', [1], 25).[2]('age').get();

Drag options to blanks, or click blank then click option'

A>

BorderBy

C<

Dlimit

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' instead of '>' for filtering older users.

The where clause filters users older than 25 using '>'. The orderBy method sorts results by age.

5fill in blank

hard

Fill all three blanks to update a user's email and log success.

Firebase

db.collection('users').doc([1]).[2]({ email: [3] }).then(() => { console.log('Email updated'); });

Drag options to blanks, or click blank then click option'

A'user123'

Bupdate

C'[e-mail]'

Dset

Attempts:

3 left

💡 Hint

Common Mistakes

Using set overwrites the whole document.

The doc method needs the document ID as a string. The update method changes fields without overwriting the whole document. The new email must be a string.