Nested objects and arrays in Firebase - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to add a nested object to Firestore.

Firebase

db.collection('users').doc('user1').set({ profile: [1] })

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

Anull

B['Alice', 30]

C'Alice'

D{ name: 'Alice', age: 30 }

Attempts:

3 left

💡 Hint

Common Mistakes

Using an array instead of an object.

Using a string instead of an object.

The nested object must be an object with keys and values, not an array or string.

2fill in blank

medium

Complete the code to add an array of strings inside a Firestore document.

Firebase

db.collection('tasks').doc('task1').set({ tags: [1] })

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

A['urgent', 'home']

Burgent, home

C'urgent, home'

D{ 'urgent', 'home' }

Attempts:

3 left

💡 Hint

Common Mistakes

Using curly braces {} which create objects, not arrays.

Using a string instead of an array.

Arrays in Firestore are represented as JavaScript arrays with square brackets [].

3fill in blank

hard

Fix the error in the nested object assignment to Firestore.

Firebase

db.collection('orders').doc('order1').set({ details: [1] })

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

A{ item: 'book', qty: 2 }

Bitem: 'book', qty: 2

C'{ item: book, qty: 2 }'

D[{ item: 'book', qty: 2 }]

Attempts:

3 left

💡 Hint

Common Mistakes

Using a string instead of an object.

Using an array when an object is expected.

The nested object must be an object literal, not a string or incomplete syntax.

4fill in blank

hard

Fill both blanks to create a nested object with an array inside Firestore.

Firebase

db.collection('projects').doc('proj1').set({ info: [1], tags: [2] })

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

A{ name: 'Build Shed', status: 'open' }

B['open', 'urgent']

C{ name: 'Build Shed', status: 'closed' }

D['done', 'low']

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping object and array types.

Using strings instead of arrays or objects.

The 'info' field is an object, and 'tags' is an array of strings.

5fill in blank

hard

Fill all three blanks to create a Firestore document with nested objects and arrays.

Firebase

db.collection('events').doc('event1').set({ organizer: [1], attendees: [2], details: [3] })

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

A{ name: 'John Doe', contact: '[e-mail]' }

B['Alice', 'Bob', 'Charlie']

C{ date: '2024-07-01', location: 'Park' }

D['2024-07-01', 'Park']

Attempts:

3 left

💡 Hint

Common Mistakes

Using arrays where objects are needed.

Using strings instead of arrays or objects.

The 'organizer' and 'details' fields are objects, while 'attendees' is an array of strings.