| /* |
| * 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.beam.sdk.extensions.sql.impl.rel; |
| |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.List; |
| import java.util.function.Function; |
| import java.util.stream.Collectors; |
| import java.util.stream.IntStream; |
| import java.util.stream.Stream; |
| import org.apache.beam.sdk.extensions.sql.impl.planner.BeamCostModel; |
| import org.apache.beam.sdk.extensions.sql.impl.planner.BeamRelMetadataQuery; |
| import org.apache.beam.sdk.extensions.sql.impl.planner.NodeStats; |
| import org.apache.beam.sdk.extensions.sql.impl.utils.CalciteUtils; |
| import org.apache.beam.sdk.schemas.Schema; |
| import org.apache.beam.sdk.transforms.DoFn; |
| import org.apache.beam.sdk.transforms.PTransform; |
| import org.apache.beam.sdk.transforms.ParDo; |
| import org.apache.beam.sdk.values.PCollection; |
| import org.apache.beam.sdk.values.PCollectionList; |
| import org.apache.beam.sdk.values.Row; |
| import org.apache.beam.vendor.calcite.v1_28_0.org.apache.calcite.plan.RelOptCluster; |
| import org.apache.beam.vendor.calcite.v1_28_0.org.apache.calcite.plan.RelOptPlanner; |
| import org.apache.beam.vendor.calcite.v1_28_0.org.apache.calcite.plan.RelTraitSet; |
| import org.apache.beam.vendor.calcite.v1_28_0.org.apache.calcite.rel.RelNode; |
| import org.apache.beam.vendor.calcite.v1_28_0.org.apache.calcite.rel.RelWriter; |
| import org.apache.beam.vendor.calcite.v1_28_0.org.apache.calcite.rel.core.Correlate; |
| import org.apache.beam.vendor.calcite.v1_28_0.org.apache.calcite.rel.core.JoinRelType; |
| import org.apache.beam.vendor.calcite.v1_28_0.org.apache.calcite.rel.core.Uncollect; |
| import org.apache.beam.vendor.calcite.v1_28_0.org.apache.calcite.rel.type.RelDataType; |
| import org.apache.beam.vendor.calcite.v1_28_0.org.apache.calcite.sql.validate.SqlValidatorUtil; |
| import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.collect.ImmutableList; |
| import org.checkerframework.checker.nullness.qual.Nullable; |
| |
| /** |
| * {@link BeamRelNode} to implement UNNEST, supporting specifically only {@link Correlate} with |
| * {@link Uncollect}. |
| */ |
| @SuppressWarnings({ |
| "nullness" // TODO(https://github.com/apache/beam/issues/20497) |
| }) |
| public class BeamUnnestRel extends Uncollect implements BeamRelNode { |
| |
| private final RelDataType unnestType; |
| private final List<Integer> unnestIndices; |
| |
| public BeamUnnestRel( |
| RelOptCluster cluster, |
| RelTraitSet traitSet, |
| RelNode input, |
| RelDataType unnestType, |
| List<Integer> unnestIndices) { |
| super(cluster, traitSet, input); |
| this.unnestType = unnestType; |
| this.unnestIndices = unnestIndices; |
| } |
| |
| @Override |
| public Uncollect copy(RelTraitSet traitSet, RelNode input) { |
| return new BeamUnnestRel(getCluster(), traitSet, input, unnestType, unnestIndices); |
| } |
| |
| @Override |
| protected RelDataType deriveRowType() { |
| return SqlValidatorUtil.deriveJoinRowType( |
| input.getRowType(), |
| unnestType, |
| JoinRelType.INNER, |
| getCluster().getTypeFactory(), |
| null, |
| ImmutableList.of()); |
| } |
| |
| @Override |
| public NodeStats estimateNodeStats(BeamRelMetadataQuery mq) { |
| // We estimate the average length of each array by a constant. |
| // We might be able to get an estimate of the length by making a MetadataHandler for this |
| // purpose, and get the estimate by reading the first couple of the rows in the source. |
| return BeamSqlRelUtils.getNodeStats(this.input, mq).multiply(2); |
| } |
| |
| @Override |
| public BeamCostModel beamComputeSelfCost(RelOptPlanner planner, BeamRelMetadataQuery mq) { |
| NodeStats estimates = BeamSqlRelUtils.getNodeStats(this, mq); |
| return BeamCostModel.FACTORY.makeCost(estimates.getRowCount(), estimates.getRate()); |
| } |
| |
| @Override |
| public RelWriter explainTerms(RelWriter pw) { |
| return super.explainTerms(pw).item("unnestIndices", unnestIndices); |
| } |
| |
| @Override |
| public PTransform<PCollectionList<Row>, PCollection<Row>> buildPTransform() { |
| return new Transform(); |
| } |
| |
| private class Transform extends PTransform<PCollectionList<Row>, PCollection<Row>> { |
| @Override |
| public PCollection<Row> expand(PCollectionList<Row> pinput) { |
| // The set of rows where we run the correlated unnest for each row |
| PCollection<Row> outer = pinput.get(0); |
| |
| Schema joinedSchema = CalciteUtils.toSchema(getRowType()); |
| |
| return outer |
| .apply(ParDo.of(new UnnestFn(joinedSchema, unnestIndices))) |
| .setRowSchema(joinedSchema); |
| } |
| } |
| |
| private static class UnnestFn extends DoFn<Row, Row> { |
| |
| private final Schema outputSchema; |
| private final List<Integer> unnestIndices; |
| |
| private UnnestFn(Schema outputSchema, List<Integer> unnestIndices) { |
| this.outputSchema = outputSchema; |
| this.unnestIndices = unnestIndices; |
| } |
| /** |
| * This is recursive call to get all the values of the nested rows. The recursion is bounded by |
| * the amount of nesting with in the data. This mirrors the unnest behavior of calcite towards |
| * schema. * |
| */ |
| private List<Object> getNestedRowBaseValues(Row nestedRow) { |
| return IntStream.range(0, nestedRow.getFieldCount()) |
| .mapToObj( |
| (i) -> { |
| List<Object> values = new ArrayList<>(); |
| Schema.FieldType fieldType = nestedRow.getSchema().getField(i).getType(); |
| if (fieldType.getTypeName().equals(Schema.TypeName.ROW)) { |
| @Nullable Row row = nestedRow.getBaseValue(i, Row.class); |
| if (row == null) { |
| return Stream.builder().build(); |
| } |
| List<Object> rowValues = getNestedRowBaseValues(row); |
| if (null != rowValues) { |
| values.addAll(rowValues); |
| } |
| } else { |
| values.add(nestedRow.getBaseValue(i)); |
| } |
| return values.stream(); |
| }) |
| .flatMap(Function.identity()) |
| .collect(Collectors.toList()); |
| } |
| |
| @ProcessElement |
| public void process(@Element Row row, OutputReceiver<Row> out) { |
| Row rowWithArrayField = row; |
| Schema schemaWithArrayField = outputSchema; |
| for (int i = unnestIndices.size() - 1; i > 0; i--) { |
| rowWithArrayField = rowWithArrayField.getRow(unnestIndices.get(i)); |
| schemaWithArrayField = |
| schemaWithArrayField.getField(unnestIndices.get(i)).getType().getRowSchema(); |
| } |
| @Nullable Collection<Object> rawValues = rowWithArrayField.getArray(unnestIndices.get(0)); |
| |
| if (rawValues == null) { |
| return; |
| } |
| Schema.TypeName typeName = |
| schemaWithArrayField |
| .getField(unnestIndices.get(0)) |
| .getType() |
| .getCollectionElementType() |
| .getTypeName(); |
| |
| for (Object uncollectedValue : rawValues) { |
| if (typeName.equals(Schema.TypeName.ROW)) { |
| Row nestedRow = (Row) uncollectedValue; |
| out.output( |
| Row.withSchema(outputSchema) |
| .addValues(row.getBaseValues()) |
| .addValues(getNestedRowBaseValues(nestedRow)) |
| .build()); |
| } else { |
| out.output( |
| Row.withSchema(outputSchema) |
| .addValues(row.getBaseValues()) |
| .addValue(uncollectedValue) |
| .build()); |
| } |
| } |
| } |
| } |
| } |
