Hi, I think that the "name" attribute of the "@JoinColumn" denotes the column name in your "User" table. The "referencedColumn" should be the name of the primary key column in your child table. So, to achieve your sql snippet, your relationship should be: @OneToOne | @JoinColumn(name="mycar_id", | referencedColumnName="car_id") | public Car getMyCar() ... But normally the @OneToOne annotation should work without any @JoinColumn annotations. The server will choose defaults for the column names. So, start with the easiest solution and remove the @JoinColumn annotation ;-). Hope this helps Wolfgang View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4217900#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...