Like E/R entities, ORM entities model
collections of real-world objects of interest
to the app
Entities have properties/attributes of database datatypes
Entities participate in relationships—see soon
(but relationships are not “first class” objects,
have no attributes)
Entities have unique ids consisting of one or more
properties
Entity instances (AKA entities) are persistent
objects of persistent classes
Entity instances correspond to database rows of
matching unique id