Am I right in assuming that any Deletion Rules defined in an Association property in the Domain Model, are applied only on the objects that are in the Entities at the moment the Deletion is called. Said otherwise, if the data in memory in the Entities is a subset of the data existing in the DataBase, I assume the Deletion rules are applied only against the data that is in memory without verifying what exists in the Database. I am also asking the same type of question on the Rule type Unique.
delete behaviour is applied on all objects in the database.
Uniqueness rules are validated by the database, thus ignoring not persisted data.