Setting FetchMode in native Hibernate
I need to set the fetch mode on my hibernate mappings to be eager in some cases, and lazy in others. I have my default (set through the hbm file) as lazy="true". How do I override this setting in code? MyClass has a set defined of type MyClass2 for which I want to set the FetchMode to EAGER.
Currently, I have something like:
Session s = HibernateUtil.getSessionFactory().openSession();
MyClass c = (MyClass)session.get(MyClass.class, myClassID);
Asked by: David942 | Posted: 21-01-2022
Answer 1
You could try something like this: (code off the top of my head)
Criteria crit = session.createCriteria(MyClass.class);
crit.add(Restrictions.eq("id", myClassId));
crit.setFetchMode("myProperty", FetchMode.EAGER);
MyClass myThingy = (MyClass)crit.uniqueResult();
I believe that FetchMode.JOIN or FetchMode.SELECT should be used instead of FetchMode.EAGER, though.
Answered by: Blake474 | Posted: 22-02-2022Answer 2
If you're not using Criteria there's also the JOIN FETCH keyword that will eagerly load the association specified by the join.
session.createQuery("select p from Parent p join fetch p.children c")
Answer 3
There is a static initialize(Object) method in the Hibernate main class. You could use that to force loading of your collection:
MyClass c = (MyClass)session.get(MyClass.class, myClassID);
Hibernate.initialize(c.getMySetOfMyClass2());
However, a default value of lazy fetching is just that: a default value. You probably want to override the laziness in the mapping for your particular Set.
Answered by: Aldus377 | Posted: 22-02-2022Similar questions
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