Index management in Firebase - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a single-field index on the 'age' field in Firestore.

Firebase

firestore.collection('users').orderBy('[1]').get()

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

Aname

Bage

Cemail

Daddress

Attempts:

3 left

💡 Hint

Common Mistakes

Using a field name that does not exist in the collection.

The 'orderBy' method requires the field name to create an index. Here, 'age' is the correct field.

2fill in blank

medium

Complete the code to create a composite index query filtering by 'status' and ordering by 'createdAt'.

Firebase

firestore.collection('orders').where('status', '==', '[1]').orderBy('createdAt').get()

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

Ashipped

Bcompleted

Ccancelled

Dpending

Attempts:

3 left

💡 Hint

Common Mistakes

Using a status value that does not exist in the data.

The 'where' clause filters documents with 'status' equal to 'pending'. This requires a composite index with 'status' and 'createdAt'.

3fill in blank

hard

Fix the error in the Firestore query by completing the missing index field.

Firebase

firestore.collection('products').orderBy('category').orderBy('[1]').get()

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

Aprice

Bname

Cstock

Drating

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing a field that is not indexed or not relevant for sorting.

When ordering by multiple fields, Firestore requires a composite index. 'price' is commonly used with 'category' for sorting products.

4fill in blank

hard

Fill both blanks to create a Firestore query that filters by 'type' and orders by 'timestamp' descending.

Firebase

firestore.collection('events').where('type', '==', '[1]').orderBy('timestamp', '[2]').get()

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

Aconference

Basc

Cdesc

Dmeetup

Attempts:

3 left

💡 Hint

Common Mistakes

Using ascending order when descending is required.

The query filters events of type 'conference' and orders them by 'timestamp' in descending order.

5fill in blank

hard

Fill all three blanks to create a Firestore query that filters by 'status', orders by 'priority' ascending, and limits results to 10.

Firebase

firestore.collection('tasks').where('status', '==', '[1]').orderBy('[2]', '[3]').limit(10).get()

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

Ain_progress

Bpriority

Casc

Ddesc

Attempts:

3 left

💡 Hint

Common Mistakes

Using descending order when ascending is needed.

Choosing wrong field names.

This query fetches tasks with status 'in_progress', ordered by 'priority' ascending, limited to 10 results.