Google Cloud Functions triggers and Database quota consumption

Question

I would like to know if the Firestore/Realtime Database quota is consumed when a google cloud function is triggered.

For example:

Firestore:

A client pushes a write operation to a document. At the same time, cloud function has an onWrite trigger for that document.

When onWrite is triggered, we have a DocumentSnapshot as parameter.

Does it mean that a read operation just happened?

What about the other triggers (also considering Realtime Database)?

Answer 1

Cloud Functions trigger invocations do not count as reads or writes against the product that generated it. However, if you write code inside the function to read or write the database, that will be billed normally.