Hibernate throws MultipleBagFetchException - cannot simultaneously fetch multiple bags

Question

Hibernate throws this exception during SessionFactory creation:

org.hibernate.loader.MultipleBagFetchException: cannot simultaneously fetch multiple b

Answer 1

Add a Hibernate-specific @Fetch annotation to your code:

@OneToMany(mappedBy="parent", fetch=FetchType.EAGER)
@Fetch(value = FetchMode.SUBSELECT)
private List childs;

This should fix the issue, related to Hibernate bug HHH-1718