javax.persistence

Annotation Type UniqueConstraint

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

Specifies 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

Required Elements

Modifier and Type	Required Element and Description
String[]	columnNames (Required) An array of the column names that make up the constraint.

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
String	name (Optional) Constraint name.

Element Detail

columnNames

public abstract String[] columnNames

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

name

public abstract String name

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

Since:

Java Persistence 2.0

Default:

""