Firestore Charges for Reads, Writes, and Delete

Within Firestore, you can have on-delete on created and on modified Cloud Functions. So in this case, it would be on modified or on-changed. This really comes back to the Firestore charging model, because you're getting charged for reads, writes, and deletes. Reads are cheapest, I think. Rites are more expensive and deletes, I don't remember. I think it's the most expensive. All right, so then with this particular model, you would have hundreds of reads but then you don't need to change anything in many places. But if you're dealing with data duplication, then the reads would get significantly less.