io.crate.planner.consumer.SimpleSelect.java Source code

Introduction

Here is the source code for io.crate.planner.consumer.SimpleSelect.java

Source

/*
 * Licensed to Crate under one or more contributor license agreements.
 * See the NOTICE file distributed with this work for additional
 * information regarding copyright ownership.  Crate licenses this file
 * to you 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.
 *
 * However, if you have executed another commercial license agreement
 * with Crate these terms will supersede the license and you may use the
 * software solely pursuant to the terms of the relevant commercial
 * agreement.
 */

package io.crate.planner.consumer;

import com.google.common.collect.ImmutableList;
import io.crate.operation.Paging;
import io.crate.operation.projectors.TopN;
import io.crate.planner.node.dql.MergePhase;
import io.crate.planner.node.dql.RoutedCollectPhase;

import javax.annotation.Nullable;

public class SimpleSelect {

    public static void enablePagingIfApplicable(RoutedCollectPhase collectPhase, @Nullable MergePhase mergePhase,
            @Nullable Integer limit, int offset, String localNodeId) {
        if (mergePhase == null || limit == null || limit == TopN.NO_LIMIT || (limit + offset) < Paging.PAGE_SIZE) {
            return;
        }
        mergePhase.executionNodes(ImmutableList.of(localNodeId));

        if (collectPhase.nodePageSizeHint() != null) {
            // in the directResponse case nodePageSizeHint has probably be set to limit
            // since it is now push based we can reduce the nodePageSizeHint
            collectPhase.pageSizeHint(limit + offset);
        }
    }
}