Hi Rick, thank you for the fast responses!
Yes I successfully tried the solution IBM proposed. But why do I have to add this property just for OneToOne relationships in order to make them work properly? For all other relationships this is not necessary. I really would like to understand this difference. Are there any side effects for the persistence mappings by adding the openjpa.jdbc.SchemaFactory property to the PU? I'm suspicious of adding properties to get things to work which in my opinion should work without further configuration. I wonder if creating both sides of a OneToOne relationship and persisting them by saving the parent entity is a special case. -- View this message in context: http://openjpa.208410.n2.nabble.com/Constraint-violation-using-OneToOne-relationship-tp6978223p6978516.html Sent from the OpenJPA Users mailing list archive at Nabble.com.