Github user twalthr commented on a diff in the pull request: https://github.com/apache/flink/pull/5327#discussion_r182660019 --- Diff: flink-libraries/flink-table/src/main/scala/org/apache/flink/table/runtime/join/NonWindowOuterJoin.scala --- @@ -0,0 +1,303 @@ +/* + * 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.table.runtime.join + +import org.apache.flink.api.common.state._ +import org.apache.flink.api.common.typeinfo.TypeInformation +import org.apache.flink.api.java.tuple.{Tuple2 => JTuple2} +import org.apache.flink.configuration.Configuration +import org.apache.flink.streaming.api.functions.co.CoProcessFunction +import org.apache.flink.table.api.{StreamQueryConfig, Types} +import org.apache.flink.table.runtime.types.CRow +import org.apache.flink.types.Row +import org.apache.flink.util.Collector + +/** + * Connect data for left stream and right stream. Base class for stream non-window outer Join. + * + * @param leftType the input type of left stream + * @param rightType the input type of right stream + * @param resultType the output type of join + * @param genJoinFuncName the function code of other non-equi condition + * @param genJoinFuncCode the function name of other non-equi condition + * @param isLeftJoin the type of join, whether it is the type of left join + * @param queryConfig the configuration for the query to generate + */ +abstract class NonWindowOuterJoin( + leftType: TypeInformation[Row], + rightType: TypeInformation[Row], + resultType: TypeInformation[CRow], + genJoinFuncName: String, + genJoinFuncCode: String, + isLeftJoin: Boolean, + queryConfig: StreamQueryConfig) + extends NonWindowJoin( + leftType, + rightType, + resultType, + genJoinFuncName, + genJoinFuncCode, + queryConfig) { + + // result row, all fields from right will be null. Used for output when there is no matched rows. + protected var leftResultRow: Row = _ + // result row, all fields from left will be null. Used for output when there is no matched rows. + protected var rightResultRow: Row = _ + // how many matched rows from the right table for each left row. Index 0 is used for left + // stream, index 1 is used for right stream. + protected var joinCntState: Array[MapState[Row, Long]] = _ + + override def open(parameters: Configuration): Unit = { + super.open(parameters) + + leftResultRow = new Row(resultType.getArity) + rightResultRow = new Row(resultType.getArity) + + joinCntState = new Array[MapState[Row, Long]](2) + val leftJoinCntStateDescriptor = new MapStateDescriptor[Row, Long]( + "leftJoinCnt", leftType, Types.LONG.asInstanceOf[TypeInformation[Long]]) + joinCntState(0) = getRuntimeContext.getMapState(leftJoinCntStateDescriptor) + val rightJoinCntStateDescriptor = new MapStateDescriptor[Row, Long]( + "rightJoinCnt", rightType, Types.LONG.asInstanceOf[TypeInformation[Long]]) + joinCntState(1) = getRuntimeContext.getMapState(rightJoinCntStateDescriptor) + + LOG.debug(s"Instantiating NonWindowOuterJoin") + } + + /** + * Join current row with other side rows. Preserve current row if there are no matched rows + * from other side. + */ + def preservedJoin( + inputRow: Row, + inputRowFromLeft: Boolean, + otherSideState: MapState[Row, JTuple2[Long, Long]], + curProcessTime: Long): Long = { + + val otherSideIterator = otherSideState.iterator() + while (otherSideIterator.hasNext) { + val otherSideEntry = otherSideIterator.next() + val otherSideRow = otherSideEntry.getKey + val otherSideCntAndExpiredTime = otherSideEntry.getValue + // join + cRowWrapper.setTimes(otherSideCntAndExpiredTime.f0) + callJoinFunction(inputRow, inputRowFromLeft, otherSideRow, cRowWrapper) + // clear expired data. Note: clear after join to keep closer to the original semantics + if (stateCleaningEnabled && curProcessTime >= otherSideCntAndExpiredTime.f1) { + otherSideIterator.remove() + } + } + val joinCnt = cRowWrapper.getEmitCnt + // The result is NULL from the other side, if there is no match. + if (joinCnt == 0) { + cRowWrapper.setTimes(1) + collectAppendNull(inputRow, inputRowFromLeft, cRowWrapper) + } + joinCnt + } + + /** + * Join current row with other side rows. Retract previous output row if matched condition + * changed, i.e, matched condition is changed from matched to unmatched or vice versa. + */ + def retractJoin( --- End diff -- Move this method to `NonWindowLeftRightJoin`?
---