Session saveorupdate not updating
Save Or Update persists both a completely new object and a loaded object that's currently attached to the session.
So this works (assuming you have a find By Name method somewhere and there's another attribute, let's say favorite Color): But that's not what you want, right?
It only looks at the id of User u2, sees that it's not set, concludes that u2 should be inserted, tries that and reports an exception.
Apart from object-relational mapping itself, one of the problems that Hibernate was intended to solve is the problem of managing entities during runtime.
The notion of “persistence context” is Hibernate’s solution to this problem.
Persistence context can be thought of as a container or a first-level cache for all the objects that you loaded or saved to a database during a session.
The session is a logical transaction, which boundaries are defined by your application’s business logic.
update(String entity Name, Object object) : Accepts the entity name and instance of object. Update Method save Or Update() method of Session class works as save() or update() method.