I can do it using extra select like that: I'm afraid you don't understand me. In sentence ' Pro developer' I want know how solve this in software industry( I'm student without experience) where my simple function with extra select is not enough good.
I've got a Parent/Child relationship declared in my hibernate mappings. When I create and save a new parent that contains new child objects, I get an error: I thought adding the join information in the child mapping would let hibernate know to get the LIST_ID from the parent object ACCESS_LIST. I get the error upon executing this code: I do not want to have to manually set the LIST_ID on each of the objects in the Access List Members collection on Access List.
I've gone through the JBOSS documentation but I think I have misunderstood how the one-to-many and many-to-one relationships work.
Hibernate Session is the interface between java application and hibernate framework.
Today we will look into Session important methods for saving and updating data in tables – save, save Or Update, persist, update and merge.
Hibernate will check if the object is transient (it has no identifier property) and if so it will make it persistent by generating it the identifier and assigning it to session.
If the object has an identifier already it will perform exclusively; it's much easier to let Hibernate decide what is new and what is old, especially in a more complex network of objects with mixed state.
Your problem is made worse by your entity having a surrogate primary key and, separately, a business key (enforced via a uniqueness constraint).
If you didn't have an id field and only name as primary key, you could use merge() (for a discussion of save Or Update vs merge, look here): But you don't have that, you need to enforce both the PK constraint on id and the uniqueness on name.
FIELD) public class Address package com.journaldev.hibernate.main; import org.hibernate.
Generic Generator; import org.hibernate.annotations. Parameter; @Entity @Table(name = "ADDRESS") @Access(value=Access Type. Transaction; import com.journaldev.hibernate.model.
It is a old, mystic and dangerous knowledge to use transactions by yourself.