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ASF GitHub Bot commented on FLINK-5159: --------------------------------------- Github user fhueske commented on a diff in the pull request: https://github.com/apache/flink/pull/2811#discussion_r89883549 --- Diff: flink-libraries/flink-table/src/main/scala/org/apache/flink/api/table/plan/nodes/dataset/DataSetSingleRowJoin.scala --- @@ -0,0 +1,229 @@ +/* + * 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.flink.api.table.plan.nodes.dataset + +import org.apache.calcite.plan._ +import org.apache.calcite.rel.`type`.{RelDataType, RelDataTypeField} +import org.apache.calcite.rel.metadata.RelMetadataQuery +import org.apache.calcite.rel.{BiRel, RelNode, RelWriter} +import org.apache.calcite.rex.RexNode +import org.apache.calcite.util.mapping.IntPair +import org.apache.flink.api.common.functions.{FlatJoinFunction, FlatMapFunction} +import org.apache.flink.api.common.typeinfo.TypeInformation +import org.apache.flink.api.java.DataSet +import org.apache.flink.api.table.codegen.CodeGenerator +import org.apache.flink.api.table.runtime.{MapJoinLeftRunner, MapJoinRightRunner} +import org.apache.flink.api.table.typeutils.TypeConverter.determineReturnType +import org.apache.flink.api.table.{BatchTableEnvironment, TableConfig, TableException} + +import scala.collection.JavaConversions._ +import scala.collection.JavaConverters._ + +/** + * Flink RelNode that executes a Join where one of inputs is a single row. + */ +class DataSetSingleRowJoin( + cluster: RelOptCluster, + traitSet: RelTraitSet, + leftNode: RelNode, + rightNode: RelNode, + leftIsSingle: Boolean, + rowRelDataType: RelDataType, + joinCondition: RexNode, + joinRowType: RelDataType, + keyPairs: List[IntPair], + ruleDescription: String) + extends BiRel(cluster, traitSet, leftNode, rightNode) + with DataSetRel { + + override def deriveRowType() = rowRelDataType + + override def copy(traitSet: RelTraitSet, inputs: java.util.List[RelNode]): RelNode = { + new DataSetSingleRowJoin( + cluster, + traitSet, + inputs.get(0), + inputs.get(1), + leftIsSingle, + getRowType, + joinCondition, + joinRowType, + keyPairs, + ruleDescription) + } + + override def toString: String = { + s"$joinTypeToString(where: ($joinConditionToString), join: ($joinSelectionToString))" + } + + override def explainTerms(pw: RelWriter): RelWriter = { + super.explainTerms(pw) + .item("where", joinConditionToString) + .item("join", joinSelectionToString) + .item("joinType", joinTypeToString) + } + + override def computeSelfCost (planner: RelOptPlanner, metadata: RelMetadataQuery): RelOptCost = { + val children = this.getInputs + children.foldLeft(planner.getCostFactory.makeZeroCost()) { (cost, child) => + if (leftIsSingle && child.equals(right) || + !leftIsSingle && child.equals(left)) { + val rowCnt = metadata.getRowCount(child) + val rowSize = this.estimateRowSize(child.getRowType) + cost.plus(planner.getCostFactory.makeCost(rowCnt, rowCnt, rowCnt * rowSize)) + } else { + cost + } + } + } + + override def translateToPlan( + tableEnv: BatchTableEnvironment, + expectedType: Option[TypeInformation[Any]]): DataSet[Any] = { + + if (isConditionTypesCompatible(left.getRowType.getFieldList, --- End diff -- This check can be removed. > Improve perfomance of inner joins with a single row input > --------------------------------------------------------- > > Key: FLINK-5159 > URL: https://issues.apache.org/jira/browse/FLINK-5159 > Project: Flink > Issue Type: Improvement > Components: Table API & SQL > Reporter: Alexander Shoshin > Assignee: Alexander Shoshin > Priority: Minor > > All inner joins (including a cross join) can be implemented as a > {{MapFunction}} if one of their inputs is a single row. This row can be > passed to a {{MapFunction}} as a {{BroadcastSet}}. > This approach is going to be more lightweight than the other current > strategies. -- This message was sent by Atlassian JIRA (v6.3.4#6332)