Given the following mapping:

@OneToOne
@MapsId
@PrimaryKeyJoinColumn(name = "id") //ignored!
private User user;

The column name is simply ignored.

There are two possible workarounds:

1. Remove @MapsId and add optional=false :

   @OneToOne(optional = false)
   @PrimaryKeyJoinColumn(name = "id")
   private User user;

2. Use @JoinColumn instead of @PrimaryKeyJoinColumn

   @OneToOne
   @MapsId
   @JoinColumn(name = "id")

But my reading of the JPA spec is that the first example should work.