Vlasta Ramik ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) *created* an issue Hibernate ORM ( https://hibernate.atlassian.net/browse/HHH?atlOrigin=eyJpIjoiMDY2MmVlOTlj... ) / Bug ( https://hibernate.atlassian.net/browse/HHH-16387?atlOrigin=eyJpIjoiMDY2Mm... ) HHH-16387 ( https://hibernate.atlassian.net/browse/HHH-16387?atlOrigin=eyJpIjoiMDY2Mm... ) Entity in key not returned when querying ( https://hibernate.atlassian.net/browse/HHH-16387?atlOrigin=eyJpIjoiMDY2Mm... ) Issue Type: Bug Affects Versions: 6.2.0.CR4 Assignee: Unassigned Created: 28/Mar/2023 07:20 AM Priority: Major Reporter: Vlasta Ramik ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) in Hibernate 5 we had an entity with composite pripary key, @IdClass annotation was used there. After upgrade to H6 (6.2.0.CR4) we face an issue where part of primary key is not returned when querying. It then causes following issue: org.hibernate.HibernateException: identifier of an instance of SomeEntity was altered from SomeEntity.Key [user=null, identityProvider=idp] to SomeEntity.Key [user=1, identityProvider=idp] I've created a reproducer: https://github.com/hibernate/hibernate-test-case-templates/compare/main..... ( https://github.com/hibernate/hibernate-test-case-templates/compare/main..... ) ( https://hibernate.atlassian.net/browse/HHH-16387#add-comment?atlOrigin=ey... ) Add Comment ( https://hibernate.atlassian.net/browse/HHH-16387#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#100219- sha1:6a6077b )