How am I billed in Firestore for a whereEqualTo query?

Question

I have a collection of 100 elements. In this collection, only two elements have the field available set to true. If I use this query:

db.collection("elements").whereEqualTo("available", true);

I get 2 elements. Am I billed with 2 read operations or 100?

Thanks

Answer 1

You are going to be billed for two reads.

You will find more details in this official video: https://www.youtube.com/watch?v=6NegFl9p_sE&, in particular at 2 min 18 sec.

Answer 2

You are billed a read for each document returned from the query that originated at the server (not read from local cache).