Hibernate merge not updating
In my previous and current project, I have run into cases where I needed to save an object to database using hibernate, and from time to time, I run into some sort of Hibernate Session Exception.I did a bit of google search, and it turns out that when saving an object, I needed to make sure the object was attached to Hibernate session.Hibernate will automatically changes and save them to the database.No need to call save Or Update() or any other method.update your save Orupdate method like thispublic T save Or Update(T entity) and keep the dynamic-update=true, and you won't need that select-before-update on your mapping. But I think if you have to enable optimistic locking, this won't work.
and if you find other value then the stored one then update that you agree with that?
But In updation what i want to do is I Only want to update only those field which has been changed, e.g in my example only update_time and update_user will be changed, so only this columns should be updated not the create_user, and create_update query is also running and it is updating all the fields like,update role... The dynamic-update option only works when the entity was loaded by the session.
Hibernate must know the initial state, otherwise it can't detect which properties that has been changed.
The most important and frequently asked question in Hibernate is the difference between merge and update methods and often we can notice that developers use update() and merge() methods alternatively.
We know that both merge() and update() methods are used to update the entity and can also change the state of an object(from detached to persistent state).