Index management in Firebase - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is an index in Firebase Firestore?

An index in Firebase Firestore is a way to organize data to make searching and sorting faster. It works like a book's index, helping the database find data quickly without looking through everything.

intermediate

Why do we need composite indexes in Firestore?

Composite indexes are needed when you want to query data using multiple fields together, like filtering by city and sorting by age. Firestore uses composite indexes to speed up these complex queries.

beginner

How can you create an index in Firebase Firestore?

You can create an index in Firestore automatically when a query needs it, by clicking the link in the error message. Or, you can create indexes manually in the Firebase Console under the Indexes tab.

beginner

What happens if a required index is missing for a Firestore query?

If a required index is missing, Firestore will show an error with a direct link to create the needed index. Without the index, the query cannot run efficiently or at all.

intermediate

How does index management affect Firestore costs?

Indexes use storage space and can increase costs because Firestore charges for storage and writes. Managing indexes well helps keep costs low by only creating indexes you really need.

What is the main purpose of an index in Firestore?

A To speed up data queries

B To store user passwords

C To backup data automatically

D To encrypt data

Indexes help Firestore find data faster when you run queries.

When do you need a composite index in Firestore?

A When querying multiple fields together

B When deleting documents

C When querying a single field only

D When exporting data

Composite indexes are for queries that filter or sort by more than one field.

How can you create a missing index after a query error?

A Ignore the error and retry

B Click the link in the error message to create the index

C Restart the Firebase app

D Delete the database

Firestore provides a direct link to create the needed index when a query fails.

What is a downside of having too many indexes in Firestore?

A Slower queries

B Data loss

C Increased storage costs

D No effect

More indexes use more storage, which can increase your Firestore costs.

Where can you manage Firestore indexes manually?

A Firebase Hosting

B Google Docs

C Firebase Authentication

D Firebase Console under Indexes tab

The Firebase Console has a section to view and create indexes manually.

Explain what an index is in Firebase Firestore and why it is important.

Think about how a book index helps you find pages quickly.

Describe how to handle a Firestore query error caused by a missing index.

Firestore guides you to fix missing indexes.