Is there something atomatic in hibernate that will do the following , or do I have to use some sort of versioning

Person A selects an order to work on in a web app (does some changes)
Person B a couple of minutes later selects the same order (does some changes)
Person A commits
Person B commits

Person B's data will be the visible data . Is there something that is built into hibernate that will automatically thrown an exception indicating that a transaction is already in progress when user B trys to modify the data or do I have to implement some kind of versioning ?

Serge

Hibernate can do the versioning for you, by using a version or timestamp column, or by using the optimistic-locking attribute.