Creating collections and documents in Firebase - Quick Revision & Summary

Recall & Review

beginner

What is a collection in Firebase Firestore?

A collection is like a folder that holds multiple documents. It organizes data into groups for easy access and management.

beginner

How do you add a new document to a collection in Firebase Firestore?

You use the add() method on a collection reference to create a new document with an auto-generated ID, or doc().set() to specify the document ID.

intermediate

What is the difference between add() and set() when creating documents?

add() creates a document with a random ID inside a collection. set() writes data to a document with a specified ID, creating it if it doesn't exist.

beginner

Can a document exist without being inside a collection in Firestore?

No. Every document must be inside a collection. Collections hold documents, and documents can contain subcollections.

intermediate

What happens if you try to create a document with an ID that already exists?

Using set() will overwrite the existing document data unless you use merge options. Using add() will always create a new document with a unique ID.

In Firebase Firestore, what is the first step to add a new document?

A Create a new database

B Get a reference to a collection

C Write data directly without reference

D Delete an existing document

You must first get a reference to the collection where you want to add the document.

Which method automatically generates a document ID when adding data?

A set()

B update()

C add()

D get()

add() creates a new document with a random unique ID.

Can you create a document without specifying a collection in Firestore?

A No, documents must be inside collections

B Only for subcollections

C Only if you use the admin SDK

D Yes, documents can exist alone

Documents must always be inside collections in Firestore.

What does set() do if the document ID already exists?

A Overwrites the existing document data

B Deletes the document

C Creates a new document with a different ID

D Throws an error

set() overwrites the existing document unless merge options are used.

Which of these is true about Firestore collections?

A Collections can contain other collections directly

B Collections are the same as documents

C Documents can contain other documents

D Collections contain documents, which can have subcollections

Collections hold documents, and documents can have subcollections.

Explain how to create a new document inside a collection in Firebase Firestore.

Think about how folders and files work on your computer.

Describe the difference between the add() and set() methods when creating documents.

One is like dropping a file in a folder with a random name, the other is like naming the file yourself.