bag

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

Hibernate doesn’t allow fetching more than one bag because that would generate a Cartesian product. Now, you will find lots of answers, blog posts, videos, or other resources telling you to use a Set instead of a List for your collections. That’s terrible advice! Using Sets instead of Lists will make the MultipleBagFetchException go away, … Read more

Hibernate throws MultipleBagFetchException – cannot simultaneously fetch multiple bags

I think a newer version of hibernate (supporting JPA 2.0) should handle this. But otherwise you can work it around by annotating the collection fields with: @LazyCollection(LazyCollectionOption.FALSE) Remember to remove the fetchType attribute from the @*ToMany annotation. But note that in most cases a Set<Child> is more appropriate than List<Child>, so unless you really need … Read more