I am trying to migrate my chat application from Firestore to DynamoDB.
Currently I have 2 collections in firebase:
Users collection have all roomsIds the user is part of.
Rooms collection have some meta data such as name, icon etc. along with
Messages sub-collection have the entire payload related to a message.
I am confused when designing my Dynamo DB ERD for the same. I have developed the following ERD along with access patters listed, but I am unable to figure out the PK, SK and Secondary index if needed.