Data modeling best practices in Firebase - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a Firestore document reference for a user with ID 'user123'.

Firebase

const userRef = firestore.collection('users').[1]('user123');

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

Aget

Bdoc

Cadd

Dset

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'get' instead of 'doc' to reference a document.

The doc method gets a reference to a specific document by ID.

2fill in blank

medium

Complete the code to add a new document with data to the 'orders' collection.

Firebase

firestore.collection('orders').[1]({ item: 'book', quantity: 1 });

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Aset

Bdoc

Cadd

Dupdate

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'set' without a document reference.

The add method creates a new document with an auto-generated ID in the collection.

3fill in blank

hard

Fix the error in the code to update the user's email in Firestore.

Firebase

firestore.collection('users').doc('user123').[1]({ email: '[e-mail]' });

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Aupdate

Bset

Cget

Dadd

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'set' which overwrites the entire document.

The update method modifies existing fields without overwriting the whole document.

4fill in blank

hard

Fill both blanks to create a query that gets all orders where quantity is greater than 5.

Firebase

firestore.collection('orders').[1]('quantity', '[2]', 5).get();

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Awhere

B>

C<

DorderBy

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'orderBy' instead of 'where' for filtering.

The where method filters documents, and the operator '>' selects quantities greater than 5.

5fill in blank

hard

Fill all three blanks to create a map of user IDs to their email addresses for users with active status.

Firebase

const activeUsers = {};
firestore.collection('users').where('status', '==', 'active').get().then(snapshot => {
  snapshot.forEach(doc => {
    activeUsers[doc.[1]] = doc.data().[2];
  });
  console.log(activeUsers); // Maps [3] to emails
});

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

Aid

Bemail

Cuser IDs

Dstatus

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'status' instead of 'email' for the email field.

Use doc.id to get the user ID, doc.data().email for the email, and the map links user IDs to emails.