Markus Haarländer ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=63ef997... ) *updated* an issue Hibernate ORM ( https://hibernate.atlassian.net/browse/HHH?atlOrigin=eyJpIjoiM2EzMWI4MmZm... ) / Bug ( https://hibernate.atlassian.net/browse/HHH-16197?atlOrigin=eyJpIjoiM2EzMW... ) HHH-16197 ( https://hibernate.atlassian.net/browse/HHH-16197?atlOrigin=eyJpIjoiM2EzMW... ) Circular references of the same entity result in different Java objects when caching is enabled and using a query ( https://hibernate.atlassian.net/browse/HHH-16197?atlOrigin=eyJpIjoiM2EzMW... ) Change By: Markus Haarländer ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=63ef997... ) We switched from Hibernate 5 to 6 and observed a strange behaviour: hibernate 6.1.7 hibernate-jcache 6.1.7 ehcache 3.10.8 Model with a circular reference: Child(id=c1) -> Parent (id=p1) -> Child(id=c1) When using an EntityManager to find the Child with id=c1, everything is fine. Child result = entityManager.find(Child.class, "c1"); The returned result is the same object as the one in result.getParent().getChild(). However, when using a simple query like: Child result = entityManager.createQuery("SELECT child from Child child WHERE child.objectId = 'c1'", Child.class).getSingleResult(); The returned Child object “result” is a different Java Object than the one in result.getParent().getChild() This leads to huge problems. Please find a testcase here: [https://github.com/haarli/hibernate-orm-6|https://github.com/haarli/hiber...] (However, in this test case environment it is not even possible to execute the Query, although it's correct. An AssertionError occurs, so there might be an additional bug which checks the exact problem we have here : The child objects differ.) If you set "hibernate.cache.use_second_level_cache" to false, everything works fine Thank you for any help. ( https://hibernate.atlassian.net/browse/HHH-16197#add-comment?atlOrigin=ey... ) Add Comment ( https://hibernate.atlassian.net/browse/HHH-16197#add-comment?atlOrigin=ey... ) Get Jira notifications on your phone! Download the Jira Cloud app for Android ( https://play.google.com/store/apps/details?id=com.atlassian.android.jira.... ) or iOS ( https://itunes.apple.com/app/apple-store/id1006972087?pt=696495&ct=Em... ) This message was sent by Atlassian Jira (v1001.0.0-SNAPSHOT#100217- sha1:d96fecc )