Hi
What exactly the difference between merge() and persists(). As my "detached entity persist error" is solved by using merge in steaded
of persists()

In case anybody finds this thread...

persist() is well defined. It makes a transient instance persistent. However, it doesn't guarantee that the identifier value will be assigned to the persistent instance immediately, the assignment might happen at flush time. The spec doesn't say that, which is the problem I have with persist().

persist() also guarantees that it will not execute an INSERT statement if it is called outside of transaction boundaries. This is useful in long-running conversations with an extended Session/persistence context.

A method like persist() is required.

Update and Merge both work on detached instances, ie instances which have a corresponding entry in the DB but which are currently not attached to (or managed by) a Session. The difference between them are what happens to the instance which is passed to the function. update tries to reattach the instance, that means that there may be no other instance of the persistent entity attached to the Session right now otherwise a exception is thrown. merge, however, just copies all values to a persistent instance in the Session (which will be loaded if it is not currently loaded). The input object is not changed. So merge is more general than update, but may use more resources.

Hi
I am using persist method to save and merge method to update in my
DAO layer and I am using
@Transactional(readOnly=true) annotation in my every save method
but still i am getting the detached entity passed to persist error

please help
thank you

Hi Niki
thanks for your suggestion
bye