ngsg commented on code in PR #4115: URL: https://github.com/apache/hive/pull/4115#discussion_r1317144719
########## ql/src/java/org/apache/hadoop/hive/ql/optimizer/FiltertagAppenderProc.java: ########## @@ -0,0 +1,231 @@ +/* + * 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.hadoop.hive.ql.optimizer; + +import java.util.ArrayList; +import java.util.HashMap; +import java.util.List; +import java.util.Map; +import java.util.Stack; + +import org.apache.hadoop.hive.ql.exec.ColumnInfo; +import org.apache.hadoop.hive.ql.exec.MapJoinOperator; +import org.apache.hadoop.hive.ql.exec.ReduceSinkOperator; +import org.apache.hadoop.hive.ql.exec.Utilities; +import org.apache.hadoop.hive.ql.lib.Node; +import org.apache.hadoop.hive.ql.lib.NodeProcessorCtx; +import org.apache.hadoop.hive.ql.lib.SemanticNodeProcessor; +import org.apache.hadoop.hive.ql.parse.SemanticException; +import org.apache.hadoop.hive.ql.plan.ExprNodeConstantDesc; +import org.apache.hadoop.hive.ql.plan.ExprNodeDesc; +import org.apache.hadoop.hive.ql.plan.ExprNodeDescUtils; +import org.apache.hadoop.hive.ql.plan.ExprNodeGenericFuncDesc; +import org.apache.hadoop.hive.ql.plan.MapJoinDesc; +import org.apache.hadoop.hive.ql.plan.PlanUtils; +import org.apache.hadoop.hive.ql.plan.ReduceSinkDesc; +import org.apache.hadoop.hive.ql.plan.TableDesc; +import org.apache.hadoop.hive.ql.udf.UDFToShort; +import org.apache.hadoop.hive.ql.udf.generic.GenericUDFBridge; +import org.apache.hadoop.hive.ql.udf.generic.GenericUDFOPMultiply; +import org.apache.hadoop.hive.ql.udf.generic.GenericUDFOPNot; +import org.apache.hadoop.hive.ql.udf.generic.GenericUDFOPPlus; +import org.apache.hadoop.hive.serde.serdeConstants; +import org.apache.hadoop.hive.serde2.typeinfo.TypeInfo; +import org.apache.hadoop.hive.serde2.typeinfo.TypeInfoFactory; + +/** + * Append a filterTag computation column to ReduceSinkOperators whose child is MapJoinOperator. + * The added column expresses JoinUtil#isFiltered in the form of ExprNode. + * The added column should be located at the end of row as CommonJoinOperator expects it. + * + * This processor only affects small tables of MapJoin that run on Tez engine. + * For big table, MapJoinOperator#process() calls CommonJoinOperator#getFilteredValue(), which adds filterTag. + * For MapReduce engine, HashTableSinkOperator adds filterTag to every row. + */ +public class FiltertagAppenderProc implements SemanticNodeProcessor { + + private final TypeInfo shortType = TypeInfoFactory.getPrimitiveTypeInfo(serdeConstants.SMALLINT_TYPE_NAME); + + @Override + public Object process(Node nd, Stack<Node> stack, NodeProcessorCtx procCtx, Object... nodeOutputs) + throws SemanticException { + MapJoinOperator mapJoinOp = (MapJoinOperator) nd; + MapJoinDesc mapJoinDesc = mapJoinOp.getConf(); + + if (mapJoinDesc.getFilterMap() == null) { + return null; + } + + int[][] filterMap = mapJoinDesc.getFilterMap(); + + // 1. Extend ReduceSinkoperator if it's output is filtered by MapJoinOperator. + for (byte pos = 0; pos < filterMap.length; pos++) { + if (pos == mapJoinDesc.getPosBigTable() || filterMap[pos] == null) { + continue; + } + + ExprNodeDesc filterTagExpr = + generateFilterTagExpression(filterMap[pos], mapJoinDesc.getFilters().get(pos)); + + // Note that the parent RS for the given pos is retrieved in different way in MapJoinProcessor. + // TODO: MapJoinProcessor.convertMapJoin() fixes the order of parent operators. + // Does other callers also fix the order as well as MapJoinProcessor.convertMapJoin()? + ReduceSinkOperator parent = (ReduceSinkOperator) mapJoinOp.getParentOperators().get(pos); + ReduceSinkDesc pRsConf = parent.getConf(); + + // MapJoinProcessor.getMapJoinDesc() replaces filter expressions with backtracked one if + // adjustParentsChildren is true. + // As of now, ConvertJoinMapJoin.convertJoinDynamicPartitionedHashJoin() is the only functions that + // calls this method with adjustParentsChildren = false. Therefore, we backtrack filter expressions + // only if MapJoinDesc.isDynamicPartitionHashJoin is true, which is also the unique property of + // ConvertJoinMapJoin.convertJoinDynamicPartitionedHashJoin(). + ExprNodeDesc mapSideFilterTagExpr; + if (mapJoinDesc.isDynamicPartitionHashJoin()) { + mapSideFilterTagExpr = ExprNodeDescUtils.backtrack(filterTagExpr, mapJoinOp, parent); + } else { + mapSideFilterTagExpr = filterTagExpr; + } + String filterColumnName = "_filterTag"; + + pRsConf.getValueCols().add(mapSideFilterTagExpr); + pRsConf.getOutputValueColumnNames().add(filterColumnName); + pRsConf.getColumnExprMap() + .put(Utilities.ReduceField.VALUE + "." + filterColumnName, mapSideFilterTagExpr); + + ColumnInfo filterTagColumnInfo = + new ColumnInfo(Utilities.ReduceField.VALUE + "." + filterColumnName, shortType, "", false); + parent.getSchema().getSignature().add(filterTagColumnInfo); + + TableDesc newTableDesc = + PlanUtils.getReduceValueTableDesc( + PlanUtils.getFieldSchemasFromColumnList(pRsConf.getValueCols(), "_col")); + pRsConf.setValueSerializeInfo(newTableDesc); + } + + // 2. Update MapJoinOperator's valueFilteredTableDescs. + // Unlike HashTableSinkOperator used in MR engine, Tez engine directly passes rows from RS to MapJoin. + // Therefore, RS's writer and MapJoin's reader should have the same TableDesc. We create valueTableDesc + // here again because it can be different from RS's valueSerializeInfo due to ColumnPruner. + List<TableDesc> newMapJoinValueFilteredTableDescs = new ArrayList<>(); + for (byte pos = 0; pos < mapJoinOp.getParentOperators().size(); pos++) { + TableDesc tableDesc; + + if (pos == mapJoinDesc.getPosBigTable() || filterMap[pos] == null) { + // We did not change corresponding parent operator. Use the original tableDesc. + tableDesc = mapJoinDesc.getValueFilteredTblDescs().get(pos); + } else { + // Create a new TableDesc based on corresponding parent RSOperator. + ReduceSinkOperator parent = (ReduceSinkOperator) mapJoinOp.getParentOperators().get(pos); + ReduceSinkDesc pRsConf = parent.getConf(); + + tableDesc = + PlanUtils.getMapJoinValueTableDesc( + PlanUtils.getFieldSchemasFromColumnList(pRsConf.getValueCols(), "mapjoinvalue")); + } + + newMapJoinValueFilteredTableDescs.add(tableDesc); + } + mapJoinDesc.setValueFilteredTblDescs(newMapJoinValueFilteredTableDescs); + + return null; + } + + /** + * Generate an ExprNodeDesc that expresses the following method: + * JoinUtil#isFiltered(Object, List<ExprNodeEvaluator>, List<ObjectInspector>, int[]). + */ + private ExprNodeDesc generateFilterTagExpression(int[] filterMap, List<ExprNodeDesc> filterExprs) { + ExprNodeDesc filterTagExpr = new ExprNodeConstantDesc(shortType, (short) 0); + Map<Byte, ExprNodeDesc> filterExprMap = getFilterExprMap(filterMap, filterExprs); + + for (Map.Entry<Byte, ExprNodeDesc> entry: filterExprMap.entrySet()) { + ExprNodeDesc filterTagMaskExpr = generateFilterTagMask(entry.getKey(), entry.getValue()); + + if (filterTagExpr instanceof ExprNodeConstantDesc) { + filterTagExpr = filterTagMaskExpr; + } else { + List<ExprNodeDesc> plusArgs = new ArrayList<>(2); + plusArgs.add(filterTagMaskExpr); + plusArgs.add(filterTagExpr); + filterTagExpr = new ExprNodeGenericFuncDesc(shortType, new GenericUDFOPPlus(), plusArgs); + } + } + + return filterTagExpr; + } + + /** + * Group filterExprs by tag and merge each of them into a single boolean ExprNodeDesc using AND operator. + * filterInfo is repetition of tag and the length of corresponding filter expressions. + * For example, filterInfo = {0, 2, 1, 3} means that the first 2 elements in filterExprs belong to tag 0, + * and the remaining 3 elements belong to tag 1. + */ + private Map<Byte, ExprNodeDesc> getFilterExprMap(int[] filterInfo, List<ExprNodeDesc> filterExprs) { + Map<Byte, ExprNodeDesc> filterExprMap = new HashMap<>(); + + int exprListOffset = 0; + for (int idx = 0; idx < filterInfo.length; idx = idx + 2) { + byte tag = (byte) filterInfo[idx]; + int length = filterInfo[idx + 1]; + + int nextExprOffset = exprListOffset + length; + List<ExprNodeDesc> andArgs = filterExprs.subList(exprListOffset, nextExprOffset); + exprListOffset = nextExprOffset; + + if (andArgs.size() == 1) { + filterExprMap.put(tag, andArgs.get(0)); + } else if (andArgs.size() > 1) { + filterExprMap.put(tag, ExprNodeDescUtils.and(andArgs)); + } + } + + return filterExprMap; + } + + /** + * Generate an ExprNodeDesc that expresses thw following code: Review Comment: Thanks for catching that, I fixed it. -- This is an automated message from the Apache Git Service. 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