Getting all documents in collection in Firebase - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to get a reference to the collection named 'users'.

Firebase

const usersCollection = firestore.collection([1]);

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

A"users"

Busers

C'user'

D'users'

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting quotes around the collection name.

Using the wrong collection name.

The collection name must be a string. Using quotes around 'users' is correct.

2fill in blank

medium

Complete the code to fetch all documents from the 'users' collection.

Firebase

const snapshot = await usersCollection.[1]();

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

Aget

Bfetch

Cretrieve

DgetDocs

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'getDocs' which is from Firebase v9 modular syntax, not the older syntax.

Using 'fetch' which is not a Firestore method.

The correct method to fetch all documents from a collection in Firebase Firestore is get().

3fill in blank

hard

Fix the error in the code to loop through all documents in the snapshot.

Firebase

snapshot.forEach(doc => [1](doc.data()));

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

Aprint

Blog

Cconsole.log

Dshow

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'print' which is not a JavaScript function.

Using 'log' without 'console'.

To print data to the console in JavaScript, use console.log.

4fill in blank

hard

Fill both blanks to create a map of document IDs to their data.

Firebase

const dataMap = {};
snapshot.forEach(doc => {
  dataMap[doc.[1]] = doc.[2]();
});

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

Aid

Bdata

CgetId

DgetData

Attempts:

3 left

💡 Hint

Common Mistakes

Using methods like 'getId' or 'getData' which do not exist.

Confusing properties and methods.

Each document has an id property and a data() method to get its data.

5fill in blank

hard

Fill all three blanks to filter documents with age greater than 18 and map their names.

Firebase

const adults = snapshot.docs
  .filter(doc => doc.data().[1] [2] [3])
  .map(doc => doc.data().name);

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

Aage

B>

C18

Dname

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong field name.

Using the wrong comparison operator.

We filter documents where the 'age' field is greater than 18, then map to get their 'name'.