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/*
* Copyright (c) 2011, 2019 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0 which is available at
* http://www.eclipse.org/legal/epl-2.0,
* or the Eclipse Distribution License v. 1.0 which is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
*/
// Contributors:
// Linda DeMichiel - 2.1
package javax.persistence;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;
/**
* Used in schema generation to specify creation of an index.
*
* Note that it is not necessary to specify an index for a primary key,
* as the primary key index will be created automatically.
*
*
* The syntax of the columnList element is a
* column_list, as follows:
*
*
* column::= index_column [,index_column]*
* index_column::= column_name [ASC | DESC]
*
*
* If ASC or DESC is not specified,
* ASC (ascending order) is assumed.
*
* @see Table
* @see SecondaryTable
* @see CollectionTable
* @see JoinTable
* @see TableGenerator
*
* @since 2.1
*
*/
@Target({})
@Retention(RUNTIME)
public @interface Index {
/**
* (Optional) The name of the index; defaults to a provider-generated name.
*/
String name() default "";
/**
* (Required) The names of the columns to be included in the index,
* in order.
*/
String columnList();
/**
* (Optional) Whether the index is unique.
*/
boolean unique() default false;
}