JPA Annotations - How to retrieve a single value from a different table than the current object?

Question

How do you map a single value from a column in another table to the current object?

Example:

class Foo {
    @Id
    @Column(name=\"FOO_ID\")
    private         


        

Answer 1

Use a secondary table. This allows you to map for an entity, on a one-to-one basis, another table and define column mappings that use it.

Example:

@Entity
@Table(name = "foo")
@SecondaryTable(name = "other_table", pkJoinColumns=@PrimaryKeyJoinColumn(name="id", referencedColumnName="FOO_ID"))
public class Foo {
    @Id
    @Column(name="FOO_ID")
    private String fooId;

    @Column(name="FOO_A")
    private String fooA;

    @Column(table="OtherTable", name="barCode")
    private String barCode;
}