[jboss-user] [EJB 3.0] - NewBie @OneToOne question

[delarue]

Hi, I am currently learning EJB3 and I don't know express in EJB3 the following

SQL:
anonymous wrote : USER(
  |     user_id : int primary key
  |     mycar_id : int
  |     foreignkey(mycar_FK) (mycar_id, CAR.id)
  | )
  | 
  | CAR(car_id : int primary key)
  | 
This is a OneToOne association

@Entity
  | @Table(name="USER")
  | class User{
  |     @Id
  |     @Column(name="user_id")
  |     protected int userId;
  |     ...
  |    @OneToOne
  |    @JoinColumn(name="mycar_FK",
  |            referencedColumnName="xxx")
  |    public Car getMyCar() ...
  | }


I don't know if referencedColumnName identifies the column USER.mycar_id or the column of the target id, CAR.car_id ?

If it is mycar_id, how is done the identification of the id of CAR, CAR.car_id ?
If it is CAR.car_id, how is identified the mycar_id column ?

@Entity
  | ...
  | class Car {
  |    @Id
  |    @Column(name="car_id")
  |    protected int carId;
  | ...
  | }

I have the EJB in action book and often the foreign key and primary key have the same column name, which cause misunderstanding from my side.

Is there a sample server, which genererate the SQL code from a EJB annotation ... without testing it on a free base ?

I understood that in EJB3, the schema of a database should be created outside of the EJB3 annotation. EJB annotation should be a model expression of some sql definition. Therefore, I try to understand the EJB modeling of some SQL samples.

Thank's for help

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