org.hibernate.loader.MultipleBagFetchException: cannot simultaneously fetch multiple bags code example
Example: multibag fetch exception
List<Post> posts = entityManager.createQuery("""
select distinct p
from Post p
left join fetch p.comments
where p.id between :minId and :maxId""", Post.class)
.setParameter("minId", 1L)
.setParameter("maxId", 50L)
.setHint(QueryHints.PASS_DISTINCT_THROUGH, false)
.getResultList();
posts = entityManager.createQuery("""
select distinct p
from Post p
left join fetch p.tags t
where p in :posts""", Post.class)
.setParameter("posts", posts)
.setHint(QueryHints.PASS_DISTINCT_THROUGH, false)
.getResultList();
assertEquals(POST_COUNT, posts.size());
for(Post post : posts) {
assertEquals(POST_COMMENT_COUNT, post.getComments().size());
assertEquals(TAG_COUNT, post.getTags().size());
}