Re: fetch=FetchType.EAGER and createNativeQuery

[Edoardo Panfili]

On 10/05/10 14.43, gilbertoca wrote:
            When multiple entities are returned by a SQL query, the entities
must be specified and mapped to the column results of the SQL statement in a
[B]SqlResultSetMapping metadata[/B] definition.
.
The following query and SqlResultSetMapping metadata illustrates the return
of multiple entity
types and assumes default metadata and column name defaults.
     Query q = em.createNativeQuery(
        "SELECT o.id, o.quantity, o.item, i.id, i.name, i.description "+
        "FROM Order o, Item i " +
        "WHERE (o.quantity>  25) AND (o.item = i.id)",
        "OrderItemResults");
     @SqlResultSetMapping(name="OrderItemResults",
           entities={
               @EntityResult(entityClass=com.acme.Order.class),
               @EntityResult(entityClass=com.acme.Item.class)
           })

this example retrieves two entities directly in the same query... I 
think that this is not my situation:
I have a query:
SELECT d FROM Regista d WHERE d.nome='Alan Parker'
and a nativeQuey
SELECT * FROM regista WHERE nome='Alan Parker'

in both I
0- create the EntityManager
1- create the query
2- retrieve the first element of the result
3- close the EntityManager
4- print the test field "Regista.film" (a list of objects, 
fetch=FetchType.EAGER)

using query spet 4 prints out the list, using nativeQuery prints out "null"


Edoardo




this is a part of my code:
==========================================
public class TestFetchType {
    public static void main(String args[]) throws Exception{
        EntityManagerFactory factory;
        EntityManager em;
        Regista r1,r2;
        Query query;


        // QUERY
        factory =  Persistence.createEntityManagerFactory(
                "openjpa-demo", System.getProperties());
        em = factory.createEntityManager();
        query = em.createQuery(
"SELECT d FROM Regista d WHERE d.nome='Alan Parker'",Regista.class);
        List<Regista> list1 = (List<Regista>)(query.getResultList());
        r1 = list1.get(0);
        em.close();
        System.out.println(r1.getFilm());

        // NATIVE QUERY
        em = factory.createEntityManager();
        query = em.createNativeQuery(
"SELECT * FROM regista WHERE nome='Alan Parker'",Regista.class);
        List<Regista> list2 = (List<Regista>)(query.getResultList());
        r2 = list2.get(0);
        em.close();
        System.out.println(r2.getFilm());
    }
}

==== Regista.java ========
@Entity
@SequenceGenerator( name="SEQ_REGISTA", 
sequenceName="regista_idregista_seq", allocationSize=20 )
public class Regista {

    @Id @GeneratedValue(strategy=GenerationType.SEQUENCE, 
generator="SEQ_REGISTA")
    int idRegista;
    String nome;
    int annoNascita;

    @OneToMany(cascade={CascadeType.ALL}, mappedBy="regista", 
targetEntity=it.aspix.demoJPA.obj.Film.class, fetch=FetchType.EAGER)
    @OrderBy("rilascio")
    List<Film> film;

   /* getter and setters */
}
============================