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@Target(value={TYPE,METHOD,FIELD}) @Retention(value=RUNTIME) public @interface PrimaryKeyJoinColumn
This annotation specifies a primary key column that is used as a foreign key to join to another table.
It is used to join the primary table of an entity subclass
in the JOINED
mapping strategy
to the primary table of its superclass; it is used within a
SecondaryTable
annotation to join a secondary table
to a primary table; and it may be used in a OneToOne
mapping in which the primary key of the referencing entity
is used as a foreign key to the referenced entity.
If no PrimaryKeyJoinColumn
annotation is
specified for a subclass in the JOINED
mapping strategy, the foreign key columns are assumed
to have the same names as the primary key columns of the
primary table of the superclass
Example: Customer and ValuedCustomer subclass @Entity @Table(name="CUST") @Inheritance(strategy=JOINED) @DiscriminatorValue("CUST") public class Customer { ... } @Entity @Table(name="VCUST") @DiscriminatorValue("VCUST") @PrimaryKeyJoinColumn(name="CUST_ID") public class ValuedCustomer extends Customer { ... }
Optional Element Summary | |
---|---|
String |
columnDefinition
(Optional) The SQL fragment that is used when generating the DDL for the column. |
String |
name
The name of the primary key column of the current table. |
String |
referencedColumnName
(Optional) The name of the primary key column of the table being joined to. |
public abstract String name
Defaults to the same name as the primary key column
of the primary table of the superclass (JOINED
mapping strategy); the same
name as the primary key column of the primary table
(SecondaryTable
mapping); or the same name as the
primary key column for the table for the referencing entity
(OneToOne
mapping)
public abstract String referencedColumnName
Defaults to the same name as the primary key column
of the primary table of the superclass (JOINED
mapping strategy); the same
name as the primary key column of the primary table
(SecondaryTable
mapping); or the same name as the
primary key column for the table for the referencing entity
(OneToOne
mapping)
public abstract String columnDefinition
OneToOne
primary key association.
Defaults to the generated SQL to create a column of the inferred type.
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Copyright 2006 Sun Microsystems, Inc. All rights reserved.