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Why update() is necessary?

Hussein Baghdadi
clojure forum advocate

Joined: Nov 08, 2003
Posts: 3479

If we have a detached object and want to reconnect it to Session, we call update() method.
But really, why this is necessary? I mean what happens under the hood?
Walter Bernstein
Ranch Hand

Joined: Dec 19, 2007
Posts: 57
"What happens under the hood?"

=> your object gets reconnected/attached to the current hibernate session.
=> at some point hibernate tries to update your object in the db.

I prefer session.lock() to reconnect a object.
Walter Bernstein
Ranch Hand

Joined: Dec 19, 2007
Posts: 57
"But really, why this is necessary?"

=> If an object is not connected to a hibernate session, it is not managed by hibernate. So any change to your object will not be persisted.
[ December 26, 2007: Message edited by: Walter Bernstein ]
I agree. Here's the link:
subject: Why update() is necessary?
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