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Lazy loading does not work - crud takes long


tomee7.0.0SNAPSHOT,objectdb 2.6.4

The OneToMany Entities are filled with 40.000 Records and they have between 20-40 Columns.

It takes over 50s to load all Project Enities that contains the OneToMany Relationships.

It should be load lazy but i dont know why the query fetch all the Data.

    public void init() {
        long t0 = System.currentTimeMillis();
        projects = service.getResultList();
        Logger.getLogger(TableManager.class.getName()).log(Level.INFO, "initialize projects takes {0} s", (System.currentTimeMillis() - t0) / 1000);


public List<Project> getResultList() {
        Query query = em.createQuery("SELECT q FROM Project q", Project.class);
        return query.getResultList();


@Table(name = "PROJECT")
@SequenceGenerator(name = "PROJECT_SEQUENCE", sequenceName = "PROJECT_SEQUENCE", allocationSize = 1, initialValue = 0)
@SuppressWarnings({"PersistenceUnitPresent", "ValidAttributes"})
public class Project implements Serializable {

    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "PROJECT_SEQUENCE")
    private Long id;
    @OneToMany(cascade = CascadeType.ALL, orphanRemoval = true, mappedBy="project",fetch = FetchType.LAZY)
    private List<Datapoint> datapoint;
    @OneToMany(cascade = CascadeType.ALL, orphanRemoval = true, mappedBy="project",fetch = FetchType.LAZY)
    private List<Advalm> advalm;



On the other side if i remove all items from the OneToMany Relation at Example Datapoint (10.000 Recors).

The API need for 50 Records 1 second to remove.

for(Datapoint d: list){ em.remove(em.merge(d))}


text/x-java iconDatapoint.java (20.8KB)
1 oneToMany Relation to Advalm
text/x-java iconProject.java (3.62KB)
2 oneToMany Relations to --> Advalm and --> Datapoint

The class definitions including the lazy settings look fine.

Examining why eager load is used in your application will require posting a minimal Java console test case (see these instructions) that reproduces this situation.

ObjectDB Support
ObjectDB - Fast Object Database for Java (JPA/JDO)

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