org.apache.hadoop.hive.ql.optimizer.ConvertJoinMapJoin Maven / Gradle / Ivy
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* 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
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* 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,
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*/
package org.apache.hadoop.hive.ql.optimizer;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.Stack;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hive.conf.HiveConf;
import org.apache.hadoop.hive.ql.exec.AppMasterEventOperator;
import org.apache.hadoop.hive.ql.exec.CommonMergeJoinOperator;
import org.apache.hadoop.hive.ql.exec.DummyStoreOperator;
import org.apache.hadoop.hive.ql.exec.FileSinkOperator;
import org.apache.hadoop.hive.ql.exec.GroupByOperator;
import org.apache.hadoop.hive.ql.exec.JoinOperator;
import org.apache.hadoop.hive.ql.exec.MapJoinOperator;
import org.apache.hadoop.hive.ql.exec.MuxOperator;
import org.apache.hadoop.hive.ql.exec.Operator;
import org.apache.hadoop.hive.ql.exec.OperatorFactory;
import org.apache.hadoop.hive.ql.exec.ReduceSinkOperator;
import org.apache.hadoop.hive.ql.exec.TezDummyStoreOperator;
import org.apache.hadoop.hive.ql.lib.Node;
import org.apache.hadoop.hive.ql.lib.NodeProcessor;
import org.apache.hadoop.hive.ql.lib.NodeProcessorCtx;
import org.apache.hadoop.hive.ql.parse.OptimizeTezProcContext;
import org.apache.hadoop.hive.ql.parse.ParseContext;
import org.apache.hadoop.hive.ql.parse.SemanticException;
import org.apache.hadoop.hive.ql.plan.DynamicPruningEventDesc;
import org.apache.hadoop.hive.ql.plan.CommonMergeJoinDesc;
import org.apache.hadoop.hive.ql.plan.ExprNodeColumnDesc;
import org.apache.hadoop.hive.ql.plan.ExprNodeDesc;
import org.apache.hadoop.hive.ql.plan.JoinCondDesc;
import org.apache.hadoop.hive.ql.plan.JoinDesc;
import org.apache.hadoop.hive.ql.plan.MapJoinDesc;
import org.apache.hadoop.hive.ql.plan.OpTraits;
import org.apache.hadoop.hive.ql.plan.OperatorDesc;
import org.apache.hadoop.hive.ql.plan.Statistics;
import org.apache.hadoop.util.ReflectionUtils;
/**
* ConvertJoinMapJoin is an optimization that replaces a common join
* (aka shuffle join) with a map join (aka broadcast or fragment replicate
* join when possible. Map joins have restrictions on which joins can be
* converted (e.g.: full outer joins cannot be handled as map joins) as well
* as memory restrictions (one side of the join has to fit into memory).
*/
public class ConvertJoinMapJoin implements NodeProcessor {
static final private Log LOG = LogFactory.getLog(ConvertJoinMapJoin.class.getName());
@SuppressWarnings("unchecked")
@Override
/*
* (non-Javadoc) we should ideally not modify the tree we traverse. However,
* since we need to walk the tree at any time when we modify the operator, we
* might as well do it here.
*/
public Object
process(Node nd, Stack stack, NodeProcessorCtx procCtx, Object... nodeOutputs)
throws SemanticException {
OptimizeTezProcContext context = (OptimizeTezProcContext) procCtx;
JoinOperator joinOp = (JoinOperator) nd;
TezBucketJoinProcCtx tezBucketJoinProcCtx = new TezBucketJoinProcCtx(context.conf);
if (!context.conf.getBoolVar(HiveConf.ConfVars.HIVECONVERTJOIN)) {
// we are just converting to a common merge join operator. The shuffle
// join in map-reduce case.
Object retval = checkAndConvertSMBJoin(context, joinOp, tezBucketJoinProcCtx);
if (retval == null) {
return retval;
} else {
int pos = 0; // it doesn't matter which position we use in this case.
convertJoinSMBJoin(joinOp, context, pos, 0, false, false);
return null;
}
}
// if we have traits, and table info is present in the traits, we know the
// exact number of buckets. Else choose the largest number of estimated
// reducers from the parent operators.
int numBuckets = -1;
int estimatedBuckets = -1;
if (context.conf.getBoolVar(HiveConf.ConfVars.HIVE_CONVERT_JOIN_BUCKET_MAPJOIN_TEZ)) {
for (OperatorparentOp : joinOp.getParentOperators()) {
if (parentOp.getOpTraits().getNumBuckets() > 0) {
numBuckets = (numBuckets < parentOp.getOpTraits().getNumBuckets()) ?
parentOp.getOpTraits().getNumBuckets() : numBuckets;
}
if (parentOp instanceof ReduceSinkOperator) {
ReduceSinkOperator rs = (ReduceSinkOperator)parentOp;
estimatedBuckets = (estimatedBuckets < rs.getConf().getNumReducers()) ?
rs.getConf().getNumReducers() : estimatedBuckets;
}
}
if (numBuckets <= 0) {
numBuckets = estimatedBuckets;
if (numBuckets <= 0) {
numBuckets = 1;
}
}
} else {
numBuckets = 1;
}
LOG.info("Estimated number of buckets " + numBuckets);
int mapJoinConversionPos = getMapJoinConversionPos(joinOp, context, numBuckets);
if (mapJoinConversionPos < 0) {
Object retval = checkAndConvertSMBJoin(context, joinOp, tezBucketJoinProcCtx);
if (retval == null) {
return retval;
} else {
// only case is full outer join with SMB enabled which is not possible. Convert to regular
// join.
convertJoinSMBJoin(joinOp, context, 0, 0, false, false);
return null;
}
}
if (numBuckets > 1) {
if (context.conf.getBoolVar(HiveConf.ConfVars.HIVE_CONVERT_JOIN_BUCKET_MAPJOIN_TEZ)) {
if (convertJoinBucketMapJoin(joinOp, context, mapJoinConversionPos, tezBucketJoinProcCtx)) {
return null;
}
}
}
LOG.info("Convert to non-bucketed map join");
// check if we can convert to map join no bucket scaling.
mapJoinConversionPos = getMapJoinConversionPos(joinOp, context, 1);
if (mapJoinConversionPos < 0) {
// we are just converting to a common merge join operator. The shuffle
// join in map-reduce case.
int pos = 0; // it doesn't matter which position we use in this case.
convertJoinSMBJoin(joinOp, context, pos, 0, false, false);
return null;
}
MapJoinOperator mapJoinOp = convertJoinMapJoin(joinOp, context, mapJoinConversionPos);
// map join operator by default has no bucket cols
mapJoinOp.setOpTraits(new OpTraits(null, -1, null));
mapJoinOp.setStatistics(joinOp.getStatistics());
// propagate this change till the next RS
for (Operator childOp : mapJoinOp.getChildOperators()) {
setAllChildrenTraitsToNull(childOp);
}
return null;
}
private Object checkAndConvertSMBJoin(OptimizeTezProcContext context, JoinOperator joinOp,
TezBucketJoinProcCtx tezBucketJoinProcCtx) throws SemanticException {
// we cannot convert to bucket map join, we cannot convert to
// map join either based on the size. Check if we can convert to SMB join.
if (context.conf.getBoolVar(HiveConf.ConfVars.HIVE_AUTO_SORTMERGE_JOIN) == false) {
convertJoinSMBJoin(joinOp, context, 0, 0, false, false);
return null;
}
Class bigTableMatcherClass = null;
try {
bigTableMatcherClass =
(Class) (Class.forName(HiveConf.getVar(
context.parseContext.getConf(),
HiveConf.ConfVars.HIVE_AUTO_SORTMERGE_JOIN_BIGTABLE_SELECTOR)));
} catch (ClassNotFoundException e) {
throw new SemanticException(e.getMessage());
}
BigTableSelectorForAutoSMJ bigTableMatcher =
ReflectionUtils.newInstance(bigTableMatcherClass, null);
JoinDesc joinDesc = joinOp.getConf();
JoinCondDesc[] joinCondns = joinDesc.getConds();
Set joinCandidates = MapJoinProcessor.getBigTableCandidates(joinCondns);
if (joinCandidates.isEmpty()) {
// This is a full outer join. This can never be a map-join
// of any type. So return false.
return false;
}
int mapJoinConversionPos =
bigTableMatcher.getBigTablePosition(context.parseContext, joinOp, joinCandidates);
if (mapJoinConversionPos < 0) {
// contains aliases from sub-query
// we are just converting to a common merge join operator. The shuffle
// join in map-reduce case.
int pos = 0; // it doesn't matter which position we use in this case.
convertJoinSMBJoin(joinOp, context, pos, 0, false, false);
return null;
}
if (checkConvertJoinSMBJoin(joinOp, context, mapJoinConversionPos, tezBucketJoinProcCtx)) {
convertJoinSMBJoin(joinOp, context, mapJoinConversionPos,
tezBucketJoinProcCtx.getNumBuckets(), tezBucketJoinProcCtx.isSubQuery(), true);
} else {
// we are just converting to a common merge join operator. The shuffle
// join in map-reduce case.
int pos = 0; // it doesn't matter which position we use in this case.
convertJoinSMBJoin(joinOp, context, pos, 0, false, false);
}
return null;
}
// replaces the join operator with a new CommonJoinOperator, removes the
// parent reduce sinks
private void convertJoinSMBJoin(JoinOperator joinOp, OptimizeTezProcContext context,
int mapJoinConversionPos, int numBuckets, boolean isSubQuery, boolean adjustParentsChildren)
throws SemanticException {
ParseContext parseContext = context.parseContext;
MapJoinDesc mapJoinDesc = null;
if (adjustParentsChildren) {
mapJoinDesc = MapJoinProcessor.getMapJoinDesc(context.conf, parseContext.getOpParseCtx(),
joinOp, parseContext.getJoinContext().get(joinOp), mapJoinConversionPos, true);
} else {
JoinDesc joinDesc = joinOp.getConf();
// retain the original join desc in the map join.
mapJoinDesc =
new MapJoinDesc(null, null, joinDesc.getExprs(), null, null,
joinDesc.getOutputColumnNames(), mapJoinConversionPos, joinDesc.getConds(),
joinDesc.getFilters(), joinDesc.getNoOuterJoin(), null);
mapJoinDesc.setNullSafes(joinDesc.getNullSafes());
mapJoinDesc.setFilterMap(joinDesc.getFilterMap());
mapJoinDesc.resetOrder();
}
@SuppressWarnings("unchecked")
CommonMergeJoinOperator mergeJoinOp =
(CommonMergeJoinOperator) OperatorFactory.get(new CommonMergeJoinDesc(numBuckets,
isSubQuery, mapJoinConversionPos, mapJoinDesc), joinOp.getSchema());
OpTraits opTraits =
new OpTraits(joinOp.getOpTraits().getBucketColNames(), numBuckets, joinOp.getOpTraits()
.getSortCols());
mergeJoinOp.setOpTraits(opTraits);
mergeJoinOp.setStatistics(joinOp.getStatistics());
for (Operator parentOp : joinOp.getParentOperators()) {
int pos = parentOp.getChildOperators().indexOf(joinOp);
parentOp.getChildOperators().remove(pos);
parentOp.getChildOperators().add(pos, mergeJoinOp);
}
for (Operator childOp : joinOp.getChildOperators()) {
int pos = childOp.getParentOperators().indexOf(joinOp);
childOp.getParentOperators().remove(pos);
childOp.getParentOperators().add(pos, mergeJoinOp);
}
List> childOperators = mergeJoinOp.getChildOperators();
if (childOperators == null) {
childOperators = new ArrayList>();
mergeJoinOp.setChildOperators(childOperators);
}
List> parentOperators = mergeJoinOp.getParentOperators();
if (parentOperators == null) {
parentOperators = new ArrayList>();
mergeJoinOp.setParentOperators(parentOperators);
}
childOperators.clear();
parentOperators.clear();
childOperators.addAll(joinOp.getChildOperators());
parentOperators.addAll(joinOp.getParentOperators());
mergeJoinOp.getConf().setGenJoinKeys(false);
if (adjustParentsChildren) {
mergeJoinOp.getConf().setGenJoinKeys(true);
List> newParentOpList =
new ArrayList>();
for (Operator parentOp : mergeJoinOp.getParentOperators()) {
for (Operator grandParentOp : parentOp.getParentOperators()) {
grandParentOp.getChildOperators().remove(parentOp);
grandParentOp.getChildOperators().add(mergeJoinOp);
newParentOpList.add(grandParentOp);
}
}
mergeJoinOp.getParentOperators().clear();
mergeJoinOp.getParentOperators().addAll(newParentOpList);
List> parentOps =
new ArrayList>(mergeJoinOp.getParentOperators());
for (Operator parentOp : parentOps) {
int parentIndex = mergeJoinOp.getParentOperators().indexOf(parentOp);
if (parentIndex == mapJoinConversionPos) {
continue;
}
// insert the dummy store operator here
DummyStoreOperator dummyStoreOp = new TezDummyStoreOperator();
dummyStoreOp.setParentOperators(new ArrayList>());
dummyStoreOp.setChildOperators(new ArrayList>());
dummyStoreOp.getChildOperators().add(mergeJoinOp);
int index = parentOp.getChildOperators().indexOf(mergeJoinOp);
parentOp.getChildOperators().remove(index);
parentOp.getChildOperators().add(index, dummyStoreOp);
dummyStoreOp.getParentOperators().add(parentOp);
mergeJoinOp.getParentOperators().remove(parentIndex);
mergeJoinOp.getParentOperators().add(parentIndex, dummyStoreOp);
}
}
mergeJoinOp.cloneOriginalParentsList(mergeJoinOp.getParentOperators());
}
private void setAllChildrenTraitsToNull(Operator currentOp) {
if (currentOp instanceof ReduceSinkOperator) {
return;
}
currentOp.setOpTraits(new OpTraits(null, -1, null));
for (Operator childOp : currentOp.getChildOperators()) {
if ((childOp instanceof ReduceSinkOperator) || (childOp instanceof GroupByOperator)) {
break;
}
setAllChildrenTraitsToNull(childOp);
}
}
private boolean convertJoinBucketMapJoin(JoinOperator joinOp, OptimizeTezProcContext context,
int bigTablePosition, TezBucketJoinProcCtx tezBucketJoinProcCtx) throws SemanticException {
if (!checkConvertJoinBucketMapJoin(joinOp, context, bigTablePosition, tezBucketJoinProcCtx)) {
LOG.info("Check conversion to bucket map join failed.");
return false;
}
MapJoinOperator mapJoinOp = convertJoinMapJoin(joinOp, context, bigTablePosition);
MapJoinDesc joinDesc = mapJoinOp.getConf();
joinDesc.setBucketMapJoin(true);
// we can set the traits for this join operator
OpTraits opTraits = new OpTraits(joinOp.getOpTraits().getBucketColNames(),
tezBucketJoinProcCtx.getNumBuckets(), null);
mapJoinOp.setOpTraits(opTraits);
mapJoinOp.setStatistics(joinOp.getStatistics());
setNumberOfBucketsOnChildren(mapJoinOp);
// Once the conversion is done, we can set the partitioner to bucket cols on the small table
Map bigTableBucketNumMapping = new HashMap();
bigTableBucketNumMapping.put(joinDesc.getBigTableAlias(), tezBucketJoinProcCtx.getNumBuckets());
joinDesc.setBigTableBucketNumMapping(bigTableBucketNumMapping);
LOG.info("Setting legacy map join to " + (!tezBucketJoinProcCtx.isSubQuery()));
joinDesc.setCustomBucketMapJoin(!tezBucketJoinProcCtx.isSubQuery());
return true;
}
/*
* This method tries to convert a join to an SMB. This is done based on
* traits. If the sorted by columns are the same as the join columns then, we
* can convert the join to an SMB. Otherwise retain the bucket map join as it
* is still more efficient than a regular join.
*/
private boolean checkConvertJoinSMBJoin(JoinOperator joinOp, OptimizeTezProcContext context,
int bigTablePosition, TezBucketJoinProcCtx tezBucketJoinProcCtx) throws SemanticException {
ReduceSinkOperator bigTableRS =
(ReduceSinkOperator) joinOp.getParentOperators().get(bigTablePosition);
int numBuckets = bigTableRS.getParentOperators().get(0).getOpTraits()
.getNumBuckets();
// the sort and bucket cols have to match on both sides for this
// transformation of the join operation
for (Operator parentOp : joinOp.getParentOperators()) {
if (!(parentOp instanceof ReduceSinkOperator)) {
// could be mux/demux operators. Currently not supported
LOG.info("Found correlation optimizer operators. Cannot convert to SMB at this time.");
return false;
}
ReduceSinkOperator rsOp = (ReduceSinkOperator) parentOp;
if (checkColEquality(rsOp.getParentOperators().get(0).getOpTraits().getSortCols(), rsOp
.getOpTraits().getSortCols(), rsOp.getColumnExprMap(), tezBucketJoinProcCtx) == false) {
LOG.info("We cannot convert to SMB because the sort column names do not match.");
return false;
}
if (checkColEquality(rsOp.getParentOperators().get(0).getOpTraits().getBucketColNames(), rsOp
.getOpTraits().getBucketColNames(), rsOp.getColumnExprMap(), tezBucketJoinProcCtx)
== false) {
LOG.info("We cannot convert to SMB because bucket column names do not match.");
return false;
}
}
boolean isSubQuery = false;
if (numBuckets < 0) {
isSubQuery = true;
numBuckets = bigTableRS.getConf().getNumReducers();
}
tezBucketJoinProcCtx.setNumBuckets(numBuckets);
tezBucketJoinProcCtx.setIsSubQuery(isSubQuery);
LOG.info("We can convert the join to an SMB join.");
return true;
}
private void setNumberOfBucketsOnChildren(Operator currentOp) {
int numBuckets = currentOp.getOpTraits().getNumBuckets();
for (Operatorop : currentOp.getChildOperators()) {
if (!(op instanceof ReduceSinkOperator) && !(op instanceof GroupByOperator)) {
op.getOpTraits().setNumBuckets(numBuckets);
setNumberOfBucketsOnChildren(op);
}
}
}
/*
* If the parent reduce sink of the big table side has the same emit key cols
* as its parent, we can create a bucket map join eliminating the reduce sink.
*/
private boolean checkConvertJoinBucketMapJoin(JoinOperator joinOp,
OptimizeTezProcContext context, int bigTablePosition,
TezBucketJoinProcCtx tezBucketJoinProcCtx)
throws SemanticException {
// bail on mux-operator because mux operator masks the emit keys of the
// constituent reduce sinks
if (!(joinOp.getParentOperators().get(0) instanceof ReduceSinkOperator)) {
LOG.info("Operator is " + joinOp.getParentOperators().get(0).getName() +
". Cannot convert to bucket map join");
return false;
}
ReduceSinkOperator rs = (ReduceSinkOperator) joinOp.getParentOperators().get(bigTablePosition);
List> parentColNames = rs.getOpTraits().getBucketColNames();
Operator parentOfParent = rs.getParentOperators().get(0);
List> grandParentColNames = parentOfParent.getOpTraits().getBucketColNames();
int numBuckets = parentOfParent.getOpTraits().getNumBuckets();
// all keys matched.
if (checkColEquality(grandParentColNames, parentColNames, rs.getColumnExprMap(),
tezBucketJoinProcCtx) == false) {
LOG.info("No info available to check for bucket map join. Cannot convert");
return false;
}
/*
* this is the case when the big table is a sub-query and is probably
* already bucketed by the join column in say a group by operation
*/
boolean isSubQuery = false;
if (numBuckets < 0) {
isSubQuery = true;
numBuckets = rs.getConf().getNumReducers();
}
tezBucketJoinProcCtx.setNumBuckets(numBuckets);
tezBucketJoinProcCtx.setIsSubQuery(isSubQuery);
return true;
}
private boolean checkColEquality(List> grandParentColNames,
List> parentColNames, Map colExprMap,
TezBucketJoinProcCtx tezBucketJoinProcCtx) {
if ((grandParentColNames == null) || (parentColNames == null)) {
return false;
}
if ((parentColNames != null) && (parentColNames.isEmpty() == false)) {
for (List listBucketCols : grandParentColNames) {
// can happen if this operator does not carry forward the previous bucketing columns
// for e.g. another join operator which does not carry one of the sides' key columns
if (listBucketCols.isEmpty()) {
continue;
}
int colCount = 0;
// parent op is guaranteed to have a single list because it is a reduce sink
for (String colName : parentColNames.get(0)) {
// all columns need to be at least a subset of the parentOfParent's bucket cols
ExprNodeDesc exprNodeDesc = colExprMap.get(colName);
if (exprNodeDesc instanceof ExprNodeColumnDesc) {
if (((ExprNodeColumnDesc)exprNodeDesc).getColumn().equals(listBucketCols.get(colCount))) {
colCount++;
} else {
break;
}
}
if (colCount == parentColNames.get(0).size()) {
return true;
}
}
}
return false;
}
return false;
}
public int getMapJoinConversionPos(JoinOperator joinOp, OptimizeTezProcContext context,
int buckets) throws SemanticException {
/*
* HIVE-9038: Join tests fail in tez when we have more than 1 join on the same key and there is
* an outer join down the join tree that requires filterTag. We disable this conversion to map
* join here now. We need to emulate the behavior of HashTableSinkOperator as in MR or create a
* new operation to be able to support this. This seems like a corner case enough to special
* case this for now.
*/
if (joinOp.getConf().getConds().length > 1) {
boolean hasOuter = false;
for (JoinCondDesc joinCondDesc : joinOp.getConf().getConds()) {
switch (joinCondDesc.getType()) {
case JoinDesc.INNER_JOIN:
case JoinDesc.LEFT_SEMI_JOIN:
case JoinDesc.UNIQUE_JOIN:
hasOuter = false;
break;
case JoinDesc.FULL_OUTER_JOIN:
case JoinDesc.LEFT_OUTER_JOIN:
case JoinDesc.RIGHT_OUTER_JOIN:
hasOuter = true;
break;
default:
throw new SemanticException("Unknown join type " + joinCondDesc.getType());
}
}
if (hasOuter) {
return -1;
}
}
Set bigTableCandidateSet =
MapJoinProcessor.getBigTableCandidates(joinOp.getConf().getConds());
long maxSize = context.conf.getLongVar(
HiveConf.ConfVars.HIVECONVERTJOINNOCONDITIONALTASKTHRESHOLD);
int bigTablePosition = -1;
Statistics bigInputStat = null;
long totalSize = 0;
int pos = 0;
// bigTableFound means we've encountered a table that's bigger than the
// max. This table is either the the big table or we cannot convert.
boolean bigTableFound = false;
for (Operator parentOp : joinOp.getParentOperators()) {
Statistics currInputStat = parentOp.getStatistics();
if (currInputStat == null) {
LOG.warn("Couldn't get statistics from: "+parentOp);
return -1;
}
long inputSize = currInputStat.getDataSize();
if ((bigInputStat == null) ||
((bigInputStat != null) &&
(inputSize > bigInputStat.getDataSize()))) {
if (bigTableFound) {
// cannot convert to map join; we've already chosen a big table
// on size and there's another one that's bigger.
return -1;
}
if (inputSize/buckets > maxSize) {
if (!bigTableCandidateSet.contains(pos)) {
// can't use the current table as the big table, but it's too
// big for the map side.
return -1;
}
bigTableFound = true;
}
if (bigInputStat != null) {
// we're replacing the current big table with a new one. Need
// to count the current one as a map table then.
totalSize += bigInputStat.getDataSize();
}
if (totalSize/buckets > maxSize) {
// sum of small tables size in this join exceeds configured limit
// hence cannot convert.
return -1;
}
if (bigTableCandidateSet.contains(pos)) {
bigTablePosition = pos;
bigInputStat = currInputStat;
}
} else {
totalSize += currInputStat.getDataSize();
if (totalSize/buckets > maxSize) {
// cannot hold all map tables in memory. Cannot convert.
return -1;
}
}
pos++;
}
return bigTablePosition;
}
/*
* Once we have decided on the map join, the tree would transform from
*
* | |
* Join MapJoin
* / \ / \
* RS RS ---> RS TS (big table)
* / \ /
* TS TS TS (small table)
*
* for tez.
*/
public MapJoinOperator convertJoinMapJoin(JoinOperator joinOp, OptimizeTezProcContext context,
int bigTablePosition) throws SemanticException {
// bail on mux operator because currently the mux operator masks the emit keys
// of the constituent reduce sinks.
for (Operator parentOp : joinOp.getParentOperators()) {
if (parentOp instanceof MuxOperator) {
return null;
}
}
//can safely convert the join to a map join.
ParseContext parseContext = context.parseContext;
MapJoinOperator mapJoinOp =
MapJoinProcessor.convertJoinOpMapJoinOp(context.conf, parseContext.getOpParseCtx(), joinOp,
parseContext.getJoinContext().get(joinOp), bigTablePosition, true);
Operator parentBigTableOp =
mapJoinOp.getParentOperators().get(bigTablePosition);
if (parentBigTableOp instanceof ReduceSinkOperator) {
for (Operator p : parentBigTableOp.getParentOperators()) {
// we might have generated a dynamic partition operator chain. Since
// we're removing the reduce sink we need do remove that too.
Set> dynamicPartitionOperators = new HashSet>();
for (Operator c : p.getChildOperators()) {
if (hasDynamicPartitionBroadcast(c)) {
dynamicPartitionOperators.add(c);
}
}
for (Operator c : dynamicPartitionOperators) {
p.removeChild(c);
}
}
mapJoinOp.getParentOperators().remove(bigTablePosition);
if (!(mapJoinOp.getParentOperators().contains(parentBigTableOp.getParentOperators().get(0)))) {
mapJoinOp.getParentOperators().add(bigTablePosition,
parentBigTableOp.getParentOperators().get(0));
}
parentBigTableOp.getParentOperators().get(0).removeChild(parentBigTableOp);
for (Operator op : mapJoinOp.getParentOperators()) {
if (!(op.getChildOperators().contains(mapJoinOp))) {
op.getChildOperators().add(mapJoinOp);
}
op.getChildOperators().remove(joinOp);
}
}
return mapJoinOp;
}
private boolean hasDynamicPartitionBroadcast(Operator parent) {
boolean hasDynamicPartitionPruning = false;
for (Operator op: parent.getChildOperators()) {
while (op != null) {
if (op instanceof AppMasterEventOperator && op.getConf() instanceof DynamicPruningEventDesc) {
// found dynamic partition pruning operator
hasDynamicPartitionPruning = true;
break;
}
if (op instanceof ReduceSinkOperator || op instanceof FileSinkOperator) {
// crossing reduce sink or file sink means the pruning isn't for this parent.
break;
}
if (op.getChildOperators().size() != 1) {
// dynamic partition pruning pipeline doesn't have multiple children
break;
}
op = op.getChildOperators().get(0);
}
}
return hasDynamicPartitionPruning;
}
}
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