| /* |
| * 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.druid.sql.calcite.rel; |
| |
| import com.fasterxml.jackson.core.JsonProcessingException; |
| import org.apache.calcite.plan.RelOptCluster; |
| import org.apache.calcite.plan.RelOptCost; |
| import org.apache.calcite.plan.RelOptPlanner; |
| import org.apache.calcite.plan.RelOptRule; |
| import org.apache.calcite.plan.RelTraitSet; |
| import org.apache.calcite.rel.RelNode; |
| import org.apache.calcite.rel.RelWriter; |
| import org.apache.calcite.rel.core.Union; |
| import org.apache.calcite.rel.metadata.RelMetadataQuery; |
| import org.apache.calcite.rel.type.RelDataType; |
| import org.apache.druid.java.util.common.StringUtils; |
| import org.apache.druid.java.util.common.guava.Sequence; |
| import org.apache.druid.query.DataSource; |
| import org.apache.druid.query.TableDataSource; |
| import org.apache.druid.query.UnionDataSource; |
| import org.apache.druid.segment.column.RowSignature; |
| import org.apache.druid.sql.calcite.table.RowSignatures; |
| |
| import java.util.ArrayList; |
| import java.util.HashSet; |
| import java.util.List; |
| import java.util.Set; |
| import java.util.stream.Collectors; |
| |
| /** |
| * Represents a query on top of a {@link UnionDataSource}. This is used to represent a "UNION ALL" of regular table |
| * datasources. |
| * |
| * See {@link DruidUnionRel} for a version that can union any set of queries together (not just regular tables), |
| * but also must be the outermost rel of a query plan. In the future we expect that {@link UnionDataSource} will gain |
| * the ability to union query datasources together, and then this class could replace {@link DruidUnionRel}. |
| */ |
| public class DruidUnionDataSourceRel extends DruidRel<DruidUnionDataSourceRel> |
| { |
| private static final TableDataSource DUMMY_DATA_SOURCE = new TableDataSource("__union__"); |
| |
| private final Union unionRel; |
| private final List<String> unionColumnNames; |
| private final PartialDruidQuery partialQuery; |
| |
| private DruidUnionDataSourceRel( |
| final RelOptCluster cluster, |
| final RelTraitSet traitSet, |
| final Union unionRel, |
| final List<String> unionColumnNames, |
| final PartialDruidQuery partialQuery, |
| final QueryMaker queryMaker |
| ) |
| { |
| super(cluster, traitSet, queryMaker); |
| this.unionRel = unionRel; |
| this.unionColumnNames = unionColumnNames; |
| this.partialQuery = partialQuery; |
| } |
| |
| public static DruidUnionDataSourceRel create( |
| final Union unionRel, |
| final List<String> unionColumnNames, |
| final QueryMaker queryMaker |
| ) |
| { |
| return new DruidUnionDataSourceRel( |
| unionRel.getCluster(), |
| unionRel.getTraitSet(), |
| unionRel, |
| unionColumnNames, |
| PartialDruidQuery.create(unionRel), |
| queryMaker |
| ); |
| } |
| |
| public List<String> getUnionColumnNames() |
| { |
| return unionColumnNames; |
| } |
| |
| @Override |
| public PartialDruidQuery getPartialDruidQuery() |
| { |
| return partialQuery; |
| } |
| |
| @Override |
| public DruidUnionDataSourceRel withPartialQuery(final PartialDruidQuery newQueryBuilder) |
| { |
| return new DruidUnionDataSourceRel( |
| getCluster(), |
| getTraitSet().plusAll(newQueryBuilder.getRelTraits()), |
| unionRel, |
| unionColumnNames, |
| newQueryBuilder, |
| getQueryMaker() |
| ); |
| } |
| |
| @Override |
| public Sequence<Object[]> runQuery() |
| { |
| // runQuery doesn't need to finalize aggregations, because the fact that runQuery is happening suggests this |
| // is the outermost query and it will actually get run as a native query. Druid's native query layer will |
| // finalize aggregations for the outermost query even if we don't explicitly ask it to. |
| |
| return getQueryMaker().runQuery(toDruidQuery(false)); |
| } |
| |
| @Override |
| public DruidQuery toDruidQuery(final boolean finalizeAggregations) |
| { |
| final List<TableDataSource> dataSources = new ArrayList<>(); |
| RowSignature signature = null; |
| |
| for (final RelNode relNode : unionRel.getInputs()) { |
| final DruidRel<?> druidRel = (DruidRel<?>) relNode; |
| if (!DruidRels.isScanOrMapping(druidRel, false)) { |
| throw new CannotBuildQueryException(druidRel); |
| } |
| |
| final DruidQuery query = druidRel.toDruidQuery(false); |
| final DataSource dataSource = query.getDataSource(); |
| if (!(dataSource instanceof TableDataSource)) { |
| throw new CannotBuildQueryException(druidRel); |
| } |
| |
| if (signature == null) { |
| signature = query.getOutputRowSignature(); |
| } |
| |
| if (signature.getColumnNames().equals(query.getOutputRowSignature().getColumnNames())) { |
| dataSources.add((TableDataSource) dataSource); |
| } else { |
| throw new CannotBuildQueryException(druidRel); |
| } |
| } |
| |
| if (signature == null) { |
| // No inputs. |
| throw new CannotBuildQueryException(unionRel); |
| } |
| |
| // Sanity check: the columns we think we're building off must equal the "unionColumnNames" registered at |
| // creation time. |
| if (!signature.getColumnNames().equals(unionColumnNames)) { |
| throw new CannotBuildQueryException(unionRel); |
| } |
| |
| return partialQuery.build( |
| new UnionDataSource(dataSources), |
| signature, |
| getPlannerContext(), |
| getCluster().getRexBuilder(), |
| finalizeAggregations |
| ); |
| } |
| |
| @Override |
| public DruidQuery toDruidQueryForExplaining() |
| { |
| return partialQuery.build( |
| DUMMY_DATA_SOURCE, |
| RowSignatures.fromRelDataType( |
| unionRel.getRowType().getFieldNames(), |
| unionRel.getRowType() |
| ), |
| getPlannerContext(), |
| getCluster().getRexBuilder(), |
| false |
| ); |
| } |
| |
| @Override |
| public DruidUnionDataSourceRel asDruidConvention() |
| { |
| return new DruidUnionDataSourceRel( |
| getCluster(), |
| getTraitSet().replace(DruidConvention.instance()), |
| (Union) unionRel.copy( |
| unionRel.getTraitSet(), |
| unionRel.getInputs() |
| .stream() |
| .map(input -> RelOptRule.convert(input, DruidConvention.instance())) |
| .collect(Collectors.toList()) |
| ), |
| unionColumnNames, |
| partialQuery, |
| getQueryMaker() |
| ); |
| } |
| |
| @Override |
| public List<RelNode> getInputs() |
| { |
| return unionRel.getInputs(); |
| } |
| |
| @Override |
| public void replaceInput(int ordinalInParent, RelNode p) |
| { |
| unionRel.replaceInput(ordinalInParent, p); |
| } |
| |
| @Override |
| public RelNode copy(final RelTraitSet traitSet, final List<RelNode> inputs) |
| { |
| return new DruidUnionDataSourceRel( |
| getCluster(), |
| traitSet, |
| (Union) unionRel.copy(unionRel.getTraitSet(), inputs), |
| unionColumnNames, |
| partialQuery, |
| getQueryMaker() |
| ); |
| } |
| |
| @Override |
| public Set<String> getDataSourceNames() |
| { |
| final Set<String> retVal = new HashSet<>(); |
| |
| for (final RelNode input : unionRel.getInputs()) { |
| retVal.addAll(((DruidRel<?>) input).getDataSourceNames()); |
| } |
| |
| return retVal; |
| } |
| |
| @Override |
| public RelWriter explainTerms(RelWriter pw) |
| { |
| final String queryString; |
| final DruidQuery druidQuery = toDruidQueryForExplaining(); |
| |
| try { |
| queryString = getQueryMaker().getJsonMapper().writeValueAsString(druidQuery.getQuery()); |
| } |
| catch (JsonProcessingException e) { |
| throw new RuntimeException(e); |
| } |
| |
| for (int i = 0; i < unionRel.getInputs().size(); i++) { |
| pw.input(StringUtils.format("input#%d", i), unionRel.getInputs().get(i)); |
| } |
| |
| return pw.item("query", queryString) |
| .item("signature", druidQuery.getOutputRowSignature()); |
| } |
| |
| @Override |
| protected RelDataType deriveRowType() |
| { |
| return partialQuery.getRowType(); |
| } |
| |
| @Override |
| public RelOptCost computeSelfCost(final RelOptPlanner planner, final RelMetadataQuery mq) |
| { |
| return planner.getCostFactory().makeZeroCost(); |
| } |
| } |