A “persistent object” is
an ordinary program object tied via ORM to database
data for its long-term state
The program objects come and go as needed
Don’t confuse this with
language-provided persistence (Java/C#), a
less robust mechanism
Persistent objects have field-materialized
identity
It makes sense—Innate
object identity depends on memory addresses, a
short-lived phenomenon
So long-lived objects
(could be years…) have to be identified
this way, it’s not the database’s fault