https://firebase.google.com/docs/reference/functions/2nd-gen/node/firebase-functions.database.databaseevent
database.DatabaseEvent interface | Cloud Functions for Firebase
cloud functionsdatabaseinterfacefirebase
https://firebase.google.com/docs/reference/functions/2nd-gen/node/firebase-functions.database.databaseevent?authuser=2
database.DatabaseEvent interface | Cloud Functions for Firebase
cloud functionsdatabaseinterfacefirebase