ObjectDB ObjectDB

JoinColumn.unique - JPA annotation element

Annotation Element
javax.persistence.JoinColumn
boolean unique

(Optional) Whether the property is a unique key. This is a shortcut for the UniqueConstraint annotation at the table level and is useful for when the unique key constraint is only a single field. It is not necessary to explicitly specify this for a join column that corresponds to a primary key that is part of a foreign key.
Default value:
false
Since:
JPA 1.0