Given:

• Entity with a @OneToOne with a reverse @OneToOne mapping that uses @MapsId
• Fetch graph that does not include the @OneToOne association
• An entity instance persisted where the @OneToOne is not set.

When querying the entity with the fetch graph Hibernate creates a proxy for the association. When the proxy is accessed, the association does not evaluate to null as expected but a EntityNotFoundException is thrown.

Find reproducer attached.

one-to-one-loading-issue.zip

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