Adding documents (add vs set) in Firebase - Quick Revision & Key Differences

Recall & Review

beginner

What does the add() method do when adding a document in Firebase?

The add() method creates a new document with a unique ID automatically generated by Firebase in a collection.

beginner

How does the set() method differ from add() when adding documents?

set() writes data to a document with a specified ID. It can create or overwrite the document, unlike add() which auto-generates the ID.

beginner

Can you specify a document ID when using add() in Firebase?

No, add() automatically generates a unique document ID. To specify an ID, you must use set() with a document reference.

intermediate

What happens if you use set() on an existing document?

Using set() on an existing document overwrites its data completely unless you use the merge option to keep existing fields.

beginner

When should you prefer add() over set()?

Use add() when you want Firebase to generate a unique ID automatically and you don't need to control the document ID.

Which method automatically generates a unique document ID in Firebase?

A add()

B set()

C update()

D get()

add() creates a new document with a unique ID automatically generated by Firebase.

Which method allows you to specify the document ID when adding data?

A add()

B set()

C delete()

D listen()

set() writes data to a document with a specified ID.

What happens if you use set() on an existing document without merge option?

A It merges new data with existing data

B It deletes the document

C It throws an error

D It overwrites the entire document

set() overwrites the entire document unless merge option is used.

If you want Firebase to handle document IDs automatically, which method should you use?

A set()

B get()

C add()

D update()

add() automatically generates document IDs.

Which method is best when you need to update or create a document with a known ID?

A set()

B add()

C push()

D listen()

set() lets you specify the document ID and create or overwrite it.

Explain the difference between add() and set() methods in Firebase when adding documents.

Think about how document IDs are handled and whether you control them.

When would you choose to use add() instead of set() in your Firebase app?

Consider ease and control over document IDs.