com.linkedin.pinot.core.query.pruner.ColumnValueSegmentPruner.java Source code

Java tutorial

Introduction

Here is the source code for com.linkedin.pinot.core.query.pruner.ColumnValueSegmentPruner.java

Source

/**
 * Copyright (C) 2014-2016 LinkedIn Corp. (pinot-core@linkedin.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.
 */
package com.linkedin.pinot.core.query.pruner;

import com.linkedin.pinot.common.data.FieldSpec;
import com.linkedin.pinot.common.request.BrokerRequest;
import com.linkedin.pinot.common.request.FilterOperator;
import com.linkedin.pinot.common.utils.request.FilterQueryTree;
import com.linkedin.pinot.common.utils.request.RequestUtils;
import com.linkedin.pinot.core.common.predicate.RangePredicate;
import com.linkedin.pinot.core.indexsegment.IndexSegment;
import com.linkedin.pinot.core.segment.index.ColumnMetadata;
import com.linkedin.pinot.core.segment.index.SegmentMetadataImpl;
import java.util.List;
import java.util.Map;
import javax.annotation.Nonnull;
import org.apache.commons.configuration.Configuration;

/**
 * An implementation of SegmentPruner.
 * <p>Pruner will prune segment based on the column value inside the filter.
 */
public class ColumnValueSegmentPruner extends AbstractSegmentPruner {

    @Override
    public void init(Configuration config) {
    }

    @Override
    public boolean prune(@Nonnull IndexSegment segment, @Nonnull BrokerRequest brokerRequest) {
        FilterQueryTree filterQueryTree = RequestUtils.generateFilterQueryTree(brokerRequest);
        if (filterQueryTree == null) {
            return false;
        }
        // For realtime segment, this map can be null.
        Map<String, ColumnMetadata> columnMetadataMap = ((SegmentMetadataImpl) segment.getSegmentMetadata())
                .getColumnMetadataMap();
        return (columnMetadataMap != null) && pruneSegment(filterQueryTree, columnMetadataMap);
    }

    @Override
    public String toString() {
        return "ColumnValueSegmentPruner";
    }

    /**
     * Helper method to determine if a segment can be pruned based on the column min/max value in segment metadata and
     * the predicates on time column. The algorithm is as follows:
     *
     * <ul>
     *   <li> For leaf node: Returns true if there is a predicate on the column and apply the predicate would result in
     *   filtering out all docs of the segment, false otherwise. </li>
     *   <li> For non-leaf AND node: True if any of its children returned true, false otherwise. </li>
     *   <li> For non-leaf OR node: True if all its children returned true, false otherwise. </li>
     * </ul>
     *
     * @param filterQueryTree Filter tree for the query.
     * @param columnMetadataMap Map from column name to column metadata.
     * @return True if segment can be pruned out, false otherwise.
     */
    @SuppressWarnings("unchecked")
    @Override
    public boolean pruneSegment(@Nonnull FilterQueryTree filterQueryTree,
            @Nonnull Map<String, ColumnMetadata> columnMetadataMap) {
        FilterOperator filterOperator = filterQueryTree.getOperator();
        List<FilterQueryTree> children = filterQueryTree.getChildren();

        if (children == null || children.isEmpty()) {
            // Leaf Node

            // Skip operator other than EQUALITY and RANGE
            if ((filterOperator != FilterOperator.EQUALITY) && (filterOperator != FilterOperator.RANGE)) {
                return false;
            }

            ColumnMetadata columnMetadata = columnMetadataMap.get(filterQueryTree.getColumn());
            if (columnMetadata == null) {
                // Should not reach here after DataSchemaSegmentPruner
                return true;
            }

            Comparable minValue = columnMetadata.getMinValue();
            Comparable maxValue = columnMetadata.getMaxValue();

            if (filterOperator == FilterOperator.EQUALITY) {
                // EQUALITY

                // Doesn't have min/max value set in metadata
                if ((minValue == null) || (maxValue == null)) {
                    return false;
                }

                // Check if the value is in the min/max range
                FieldSpec.DataType dataType = columnMetadata.getDataType();
                Comparable value = getValue(filterQueryTree.getValue().get(0), dataType);
                return (value.compareTo(minValue) < 0) || (value.compareTo(maxValue) > 0);
            } else {
                // RANGE

                // Get lower/upper boundary value
                FieldSpec.DataType dataType = columnMetadata.getDataType();
                RangePredicate rangePredicate = new RangePredicate(null, filterQueryTree.getValue());
                String lowerBoundary = rangePredicate.getLowerBoundary();
                boolean includeLowerBoundary = rangePredicate.includeLowerBoundary();
                Comparable lowerBoundaryValue = null;
                if (!lowerBoundary.equals(RangePredicate.UNBOUNDED)) {
                    lowerBoundaryValue = getValue(lowerBoundary, dataType);
                }
                String upperBoundary = rangePredicate.getUpperBoundary();
                boolean includeUpperBoundary = rangePredicate.includeUpperBoundary();
                Comparable upperBoundaryValue = null;
                if (!upperBoundary.equals(RangePredicate.UNBOUNDED)) {
                    upperBoundaryValue = getValue(upperBoundary, dataType);
                }

                // Check if the range is valid
                if ((lowerBoundaryValue != null) && (upperBoundaryValue != null)) {
                    if (includeLowerBoundary && includeUpperBoundary) {
                        if (lowerBoundaryValue.compareTo(upperBoundaryValue) > 0) {
                            return true;
                        }
                    } else {
                        if (lowerBoundaryValue.compareTo(upperBoundaryValue) >= 0) {
                            return true;
                        }
                    }
                }

                // Doesn't have min/max value set in metadata
                if ((minValue == null) || (maxValue == null)) {
                    return false;
                }

                if (lowerBoundaryValue != null) {
                    if (includeLowerBoundary) {
                        if (lowerBoundaryValue.compareTo(maxValue) > 0) {
                            return true;
                        }
                    } else {
                        if (lowerBoundaryValue.compareTo(maxValue) >= 0) {
                            return true;
                        }
                    }
                }
                if (upperBoundaryValue != null) {
                    if (includeUpperBoundary) {
                        if (upperBoundaryValue.compareTo(minValue) < 0) {
                            return true;
                        }
                    } else {
                        if (upperBoundaryValue.compareTo(minValue) <= 0) {
                            return true;
                        }
                    }
                }
                return false;
            }
        } else {
            // Parent node
            return pruneNonLeaf(filterQueryTree, columnMetadataMap);
        }
    }
}