EJB entities, views and multiple id fields

I have two tables that I want to wrap in a view:

CREATE VIEW myview AS
SELECT 1 as type, key, some_col FROM table1
UNION ALL
SELECT 2 as type, key, some_col FROM table2;

Then, I want to define an EJB entity to wrap the view:

@Entity
@Table (name="myview")
public class MyEntity {

    @Id 
    @Column(name="type")
    private Integer type;

    @Id 
    @Column(name="key")
    private Integer key;

    @Column(name="some_col")
    private String someCol;
}

Note that the EJB is identified by type + key (that form a unique identifier). Is this approach correct?