Artem K. ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) *commented* on HHH-11605 ( https://hibernate.atlassian.net/browse/HHH-11605?atlOrigin=eyJpIjoiNzY3Y2... ) Re: OneToMany - extend CollectionKey with PK of the "One" side. ( https://hibernate.atlassian.net/browse/HHH-11605?atlOrigin=eyJpIjoiNzY3Y2... ) I ran into the same issue while mapping a legacy database whose structure I cannot change with Hibernate 5.4. Before stumbling upon this issue, I debugged the code and arrived at the same conclusion as Matthew Jacobs. If mapping is non-insertable and non-updatable, there does not seem to be a reason to throw an error. Would be great if this can be considered for change in the next releases. ( https://hibernate.atlassian.net/browse/HHH-11605#add-comment?atlOrigin=ey... ) Add Comment ( https://hibernate.atlassian.net/browse/HHH-11605#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#100127- sha1:97b7618 )