javax.persistence
Annotation Type UniqueConstraint

@Target(value={})
@Retention(value=RUNTIME)
public @interface UniqueConstraint

Is used to specify that a unique constraint is to be included in the generated DDL for a primary or secondary table.

    Example:
    @Entity
    @Table(
        name="EMPLOYEE", 
        uniqueConstraints=
            @UniqueConstraint(columnNames={"EMP_ID", "EMP_NAME"})
    )
    public class Employee { ... }
 

Since:

Java Persistence 1.0

Required Element Summary

java.lang.String[]

columnNames (Required) An array of the column names that make up the constraint.

Optional Element Summary

java.lang.String

name (Optional) Constraint name.

Element Detail

columnNames

public abstract java.lang.String[] columnNames

(Required) An array of the column names that make up the constraint.

name

public abstract java.lang.String name

(Optional) Constraint name. A provider-chosen name will be chosen if a name is not specified.

Since:

Java Persistence 2.0

Default:

""