@Target(value={})
@Retention(value=RUNTIME)
public @interface ForeignKey
The ConstraintMode
value is used to specify whether foreign
key constraints should be generated.
The syntax used in the foreignKeyDefinition
element
should follow the SQL syntax used by the target database for foreign
key constraints. For example, this may be similar the following:
FOREIGN KEY ( <COLUMN expression> {, <COLUMN expression>}... ) REFERENCES <TABLE identifier> [ (<COLUMN expression> {, <COLUMN expression>}... ) ] [ ON UPDATE <referential action> ] [ ON DELETE <referential action> ]When the
ConstraintMode
value is
CONSTRAINT
, but the foreignKeyDefinition
element is not specified, the provider will generate foreign key
constraints whose update and delete actions it determines most
appropriate for the join column(s) to which the foreign key
annotation is applied.JoinColumn
,
JoinColumns
,
MapKeyJoinColumn
,
MapKeyJoinColumns
,
PrimaryKeyJoinColumn
,
JoinTable
,
CollectionTable
,
SecondaryTable
,
AssociationOverride
Modifier and Type | Optional Element and Description |
---|---|
java.lang.String |
foreignKeyDefinition
(Optional) The foreign key constraint definition.
|
java.lang.String |
name
(Optional) The name of the foreign key constraint.
|
ConstraintMode |
value
(Optional) Used to specify whether a foreign key constraint should be
generated when schema generation is in effect.
|
public abstract java.lang.String name
public abstract ConstraintMode value
A value of CONSTRAINT
will cause the persistence
provider to generate a foreign key constraint. If the
foreignKeyDefinition
element is not specified, the
provider will generate a constraint whose update
and delete actions it determines most appropriate for the
join column(s) to which the foreign key annotation is applied.
A value of NO_CONSTRAINT
will result in no
constraint being generated.
A value of PROVIDER_DEFAULT
will result in the
provider's default behavior (which may or may not result
in the generation of a constraint for the given join column(s).