com.orientechnologies.orient.core.sql.operator.OIndexReuseType Maven / Gradle / Ivy

/*
  *
  *  *  Copyright 2014 Orient Technologies LTD (info(at)orientechnologies.com)
  *  *
  *  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  *  you may not use this file except in compliance with the License.
  *  *  You may obtain a copy of the License at
  *  *
  *  *       http://www.apache.org/licenses/LICENSE-2.0
  *  *
  *  *  Unless required by applicable law or agreed to in writing, software
  *  *  distributed under the License is distributed on an "AS IS" BASIS,
  *  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  *  See the License for the specific language governing permissions and
  *  *  limitations under the License.
  *  *
  *  * For more information: http://www.orientechnologies.com
  *
  */
package com.orientechnologies.orient.core.sql.operator;

/**
 * Represents hint how index can be used to calculate result of operator execution.
 *
 * @author Andrey Lomakin
 *
 * @see  OQueryOperator#getIndexReuseType(Object, Object)
 */
public enum OIndexReuseType {
	/**
	 * Results of this operator can be calculated as intersection of
	 * results for left and right operators.
	 */
	INDEX_INTERSECTION,

	/**
	 * Results of this operator can be calculated as union of
	 * results for left and right operators.
	 */
	INDEX_UNION,

	/**
	 * Index cna be used to calculate result of given operator.
	 */
	NO_INDEX,

	/**
	 * Result of execution of this operator can be replaced by call to one of
	 * {@link com.orientechnologies.orient.core.index.OIndex} methods.
	 */
	INDEX_METHOD,
    /**
     * Result of execution of this operator can be replaced by call to one of
     * {@link com.orientechnologies.orient.core.index.OIndex} methods depending on user implementation.
     */
    INDEX_OPERATOR
}