| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF 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. |
| */ |
| package org.apache.pinot.core.operator; |
| |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.Map; |
| import javax.annotation.Nullable; |
| import org.apache.pinot.core.common.DataBlockCache; |
| import org.apache.pinot.core.common.DataFetcher; |
| import org.apache.pinot.core.common.Operator; |
| import org.apache.pinot.core.operator.blocks.DocIdSetBlock; |
| import org.apache.pinot.core.operator.blocks.ProjectionBlock; |
| import org.apache.pinot.segment.spi.datasource.DataSource; |
| import org.apache.pinot.spi.trace.Tracing; |
| |
| |
| public class ProjectionOperator extends BaseOperator<ProjectionBlock> { |
| |
| private static final String EXPLAIN_NAME = "PROJECT"; |
| |
| private final Map<String, DataSource> _dataSourceMap; |
| private final BaseOperator<DocIdSetBlock> _docIdSetOperator; |
| private final DataBlockCache _dataBlockCache; |
| |
| public ProjectionOperator(Map<String, DataSource> dataSourceMap, |
| @Nullable BaseOperator<DocIdSetBlock> docIdSetOperator) { |
| _dataSourceMap = dataSourceMap; |
| _docIdSetOperator = docIdSetOperator; |
| _dataBlockCache = new DataBlockCache(new DataFetcher(dataSourceMap)); |
| } |
| |
| /** |
| * Returns the map from column to data source. |
| * |
| * @return Map from column to data source |
| */ |
| public Map<String, DataSource> getDataSourceMap() { |
| return _dataSourceMap; |
| } |
| |
| @Override |
| protected ProjectionBlock getNextBlock() { |
| // NOTE: Should not be called when _docIdSetOperator is null. |
| assert _docIdSetOperator != null; |
| DocIdSetBlock docIdSetBlock = _docIdSetOperator.nextBlock(); |
| if (docIdSetBlock == null) { |
| return null; |
| } else { |
| Tracing.activeRecording().setNumChildren(_dataSourceMap.size()); |
| _dataBlockCache.initNewBlock(docIdSetBlock.getDocIdSet(), docIdSetBlock.getSearchableLength()); |
| return new ProjectionBlock(_dataSourceMap, _dataBlockCache); |
| } |
| } |
| |
| |
| @Override |
| public List<Operator> getChildOperators() { |
| return Collections.singletonList(_docIdSetOperator); |
| } |
| |
| @Override |
| public String toExplainString() { |
| StringBuilder stringBuilder = new StringBuilder(EXPLAIN_NAME).append('('); |
| // SQL statements such as SELECT 'literal' FROM myTable don't have any projection columns. |
| if (!_dataSourceMap.keySet().isEmpty()) { |
| int count = 0; |
| for (String col : _dataSourceMap.keySet()) { |
| if (count == _dataSourceMap.keySet().size() - 1) { |
| stringBuilder.append(col); |
| } else { |
| stringBuilder.append(col).append(", "); |
| } |
| count++; |
| } |
| } |
| return stringBuilder.append(')').toString(); |
| } |
| |
| @Override |
| public ExecutionStatistics getExecutionStatistics() { |
| return _docIdSetOperator != null ? _docIdSetOperator.getExecutionStatistics() : new ExecutionStatistics(0, 0, 0, 0); |
| } |
| } |