CODEWITHSUNDEEP
javahibernate
user1417746
user1417746

Reputation: 191

Best Fetching Practices in Hibernate Mapping (Many-To-One)

I am having trouble with many-to-one mapping using hibernate. I have two tables, Table A and Table B. I mapped Many-to-One Relationship between these tables. Both tables can be use together as well as separately.

The representation of tables in terms of classes in Java like:

class A{ 
 private B b; 
 private Integer val1; 
 private Integer val2; 
 private Integer val3; 
}

class B{
 private Integer val1;
 private Integer val2;
 private Integer val3;
}

The problem is whenever I try to retrieve/fetch records from table A, hibernate also fetch records from Table B all the time which I do not want. It causing performance issues. Is their any way to deal with this situation?

Please guide me with an appropriate answer.

Upvotes: 1

Views: 2563

Answers (2)

Naresh J
Naresh J

Reputation: 2137

Your requirement fits into Lazy Initialization. For achieving it, you can add either annotation or while retrieving data you can use hibernate session's get method.

In your case you can write like :

Session session = SessionFactory.getCurrentSession();
A aObject= (A) session.get(A.class, A_ID);

As stated in this https://community.jboss.org/wiki/AShortPrimerOnFetchingStrategies?_sscc=t link :

Hibernate3 loads a single entity instance if you retrieve it by identifier through get() or load(). All collections mapped for this entity, and all associated entities, be it through to-many or to-one associations, are not loaded.

Upvotes: 0

JB Nizet
JB Nizet

Reputation: 691765

@ManyToOne(lazy = true)
private B b;

Is all you need. Read the hibernate documentation for more details.

Upvotes: 2

Related Questions