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Posted to commits@hive.apache.org by ha...@apache.org on 2015/11/11 20:32:43 UTC
hive git commit: HIVE-12186 : Upgrade Hive to Calcite 1.5 (Jesus
Camacho Rodriguez via Ashutosh Chauhan)
Repository: hive
Updated Branches:
refs/heads/master 1d5da097a -> da4b1b077
HIVE-12186 : Upgrade Hive to Calcite 1.5 (Jesus Camacho Rodriguez via Ashutosh Chauhan)
Signed-off-by: Ashutosh Chauhan <ha...@apache.org>
Project: http://git-wip-us.apache.org/repos/asf/hive/repo
Commit: http://git-wip-us.apache.org/repos/asf/hive/commit/da4b1b07
Tree: http://git-wip-us.apache.org/repos/asf/hive/tree/da4b1b07
Diff: http://git-wip-us.apache.org/repos/asf/hive/diff/da4b1b07
Branch: refs/heads/master
Commit: da4b1b07764718210377814edf06d5960d074f79
Parents: 1d5da09
Author: Jesus Camacho Rodriguez <jc...@apache.org>
Authored: Wed Nov 11 11:31:22 2015 -0800
Committer: Ashutosh Chauhan <ha...@apache.org>
Committed: Wed Nov 11 11:31:22 2015 -0800
----------------------------------------------------------------------
pom.xml | 2 +-
.../calcite/reloperators/HiveTableScan.java | 6 +-
.../calcite/rules/HiveRelFieldTrimmer.java | 143 ++-----------------
.../calcite/translator/ASTConverter.java | 34 ++---
.../calcite/translator/HiveOpConverter.java | 7 +-
.../translator/PlanModifierForASTConv.java | 3 +-
.../hadoop/hive/ql/parse/CalcitePlanner.java | 8 +-
.../bucketizedhiveinputformat.q.out | 2 +
.../spark/bucketizedhiveinputformat.q.out | 2 +
9 files changed, 38 insertions(+), 169 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/hive/blob/da4b1b07/pom.xml
----------------------------------------------------------------------
diff --git a/pom.xml b/pom.xml
index 282d077..99aeff7 100644
--- a/pom.xml
+++ b/pom.xml
@@ -105,7 +105,7 @@
<antlr.version>3.4</antlr.version>
<avro.version>1.7.7</avro.version>
<bonecp.version>0.8.0.RELEASE</bonecp.version>
- <calcite.version>1.4.0-incubating</calcite.version>
+ <calcite.version>1.5.0</calcite.version>
<datanucleus-api-jdo.version>3.2.6</datanucleus-api-jdo.version>
<datanucleus-core.version>3.2.10</datanucleus-core.version>
<datanucleus-rdbms.version>3.2.9</datanucleus-rdbms.version>
http://git-wip-us.apache.org/repos/asf/hive/blob/da4b1b07/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/reloperators/HiveTableScan.java
----------------------------------------------------------------------
diff --git a/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/reloperators/HiveTableScan.java b/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/reloperators/HiveTableScan.java
index 1831d69..446dc73 100644
--- a/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/reloperators/HiveTableScan.java
+++ b/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/reloperators/HiveTableScan.java
@@ -29,13 +29,13 @@ import org.apache.calcite.plan.RelOptPlanner;
import org.apache.calcite.plan.RelTraitSet;
import org.apache.calcite.rel.RelNode;
import org.apache.calcite.rel.RelWriter;
-import org.apache.calcite.rel.core.RelFactories;
import org.apache.calcite.rel.core.TableScan;
import org.apache.calcite.rel.metadata.RelMetadataQuery;
import org.apache.calcite.rel.type.RelDataType;
import org.apache.calcite.rel.type.RelDataTypeField;
import org.apache.calcite.rex.RexBuilder;
import org.apache.calcite.rex.RexNode;
+import org.apache.calcite.tools.RelBuilder;
import org.apache.calcite.util.ImmutableBitSet;
import org.apache.hadoop.hive.ql.optimizer.calcite.HiveCalciteUtil;
import org.apache.hadoop.hive.ql.optimizer.calcite.RelOptHiveTable;
@@ -152,7 +152,7 @@ public class HiveTableScan extends TableScan implements HiveRelNode {
@Override
public RelNode project(ImmutableBitSet fieldsUsed, Set<RelDataTypeField> extraFields,
- RelFactories.ProjectFactory projectFactory) {
+ RelBuilder relBuilder) {
// 1. If the schema is the same then bail out
final int fieldCount = getRowType().getFieldCount();
@@ -183,7 +183,7 @@ public class HiveTableScan extends TableScan implements HiveRelNode {
fieldNames));
// 5. Add Proj on top of TS
- return projectFactory.createProject(newHT, exprList, new ArrayList<String>(fieldNames));
+ return relBuilder.push(newHT).project(exprList, new ArrayList<String>(fieldNames)).build();
}
public List<Integer> getNeededColIndxsFrmReloptHT() {
http://git-wip-us.apache.org/repos/asf/hive/blob/da4b1b07/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/HiveRelFieldTrimmer.java
----------------------------------------------------------------------
diff --git a/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/HiveRelFieldTrimmer.java b/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/HiveRelFieldTrimmer.java
index a12fa2a..b543fbb 100644
--- a/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/HiveRelFieldTrimmer.java
+++ b/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/HiveRelFieldTrimmer.java
@@ -23,10 +23,9 @@ import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;
+import org.apache.calcite.plan.RelOptCluster;
import org.apache.calcite.plan.RelOptUtil;
import org.apache.calcite.rel.RelNode;
-import org.apache.calcite.rel.core.Aggregate;
-import org.apache.calcite.rel.core.AggregateCall;
import org.apache.calcite.rel.core.RelFactories;
import org.apache.calcite.rel.type.RelDataType;
import org.apache.calcite.rel.type.RelDataTypeField;
@@ -35,22 +34,23 @@ import org.apache.calcite.rex.RexPermuteInputsShuttle;
import org.apache.calcite.rex.RexVisitor;
import org.apache.calcite.sql.validate.SqlValidator;
import org.apache.calcite.sql2rel.RelFieldTrimmer;
+import org.apache.calcite.tools.RelBuilder;
import org.apache.calcite.util.ImmutableBitSet;
import org.apache.calcite.util.mapping.IntPair;
import org.apache.calcite.util.mapping.Mapping;
import org.apache.calcite.util.mapping.MappingType;
import org.apache.calcite.util.mapping.Mappings;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hive.ql.optimizer.calcite.reloperators.HiveMultiJoin;
-import com.google.common.base.Function;
-import com.google.common.collect.ImmutableList;
-import com.google.common.collect.Iterables;
-
public class HiveRelFieldTrimmer extends RelFieldTrimmer {
- private final RelFactories.AggregateFactory aggregateFactory;
+ protected static final Log LOG = LogFactory.getLog(HiveRelFieldTrimmer.class);
+
public HiveRelFieldTrimmer(SqlValidator validator,
+ RelOptCluster cluster,
RelFactories.ProjectFactory projectFactory,
RelFactories.FilterFactory filterFactory,
RelFactories.JoinFactory joinFactory,
@@ -58,9 +58,10 @@ public class HiveRelFieldTrimmer extends RelFieldTrimmer {
RelFactories.SortFactory sortFactory,
RelFactories.AggregateFactory aggregateFactory,
RelFactories.SetOpFactory setOpFactory) {
- super(validator, projectFactory, filterFactory, joinFactory,
- semiJoinFactory, sortFactory, aggregateFactory, setOpFactory);
- this.aggregateFactory = aggregateFactory;
+ super(validator,
+ RelBuilder.proto(projectFactory, filterFactory, joinFactory,
+ semiJoinFactory, sortFactory, aggregateFactory, setOpFactory)
+ .create(cluster, null));
}
/**
@@ -155,127 +156,5 @@ public class HiveRelFieldTrimmer extends RelFieldTrimmer {
return new TrimResult(newJoin, mapping);
}
- /**
- * Variant of {@link #trimFields(RelNode, ImmutableBitSet, Set)} for
- * {@link org.apache.calcite.rel.logical.LogicalAggregate}.
- */
- @Override
- public TrimResult trimFields(
- Aggregate aggregate,
- ImmutableBitSet fieldsUsed,
- Set<RelDataTypeField> extraFields) {
- // Fields:
- //
- // | sys fields | group fields | indicator fields | agg functions |
- //
- // Two kinds of trimming:
- //
- // 1. If agg rel has system fields but none of these are used, create an
- // agg rel with no system fields.
- //
- // 2. If aggregate functions are not used, remove them.
- //
- // But group and indicator fields stay, even if they are not used.
-
- final RelDataType rowType = aggregate.getRowType();
-
- // Compute which input fields are used.
- // 1. group fields are always used
- final ImmutableBitSet.Builder inputFieldsUsed =
- ImmutableBitSet.builder(aggregate.getGroupSet());
- // 2. agg functions
- for (AggregateCall aggCall : aggregate.getAggCallList()) {
- for (int i : aggCall.getArgList()) {
- inputFieldsUsed.set(i);
- }
- if (aggCall.filterArg >= 0) {
- inputFieldsUsed.set(aggCall.filterArg);
- }
- }
-
- // Create input with trimmed columns.
- final RelNode input = aggregate.getInput();
- final Set<RelDataTypeField> inputExtraFields = Collections.emptySet();
- final TrimResult trimResult =
- trimChild(aggregate, input, inputFieldsUsed.build(), inputExtraFields);
- final RelNode newInput = trimResult.left;
- final Mapping inputMapping = trimResult.right;
-
- // We have to return group keys and (if present) indicators.
- // So, pretend that the consumer asked for them.
- final int groupCount = aggregate.getGroupSet().cardinality();
- final int indicatorCount = aggregate.getIndicatorCount();
- fieldsUsed =
- fieldsUsed.union(ImmutableBitSet.range(groupCount + indicatorCount));
-
- // If the input is unchanged, and we need to project all columns,
- // there's nothing to do.
- if (input == newInput
- && fieldsUsed.equals(ImmutableBitSet.range(rowType.getFieldCount()))) {
- return new TrimResult(
- aggregate,
- Mappings.createIdentity(rowType.getFieldCount()));
- }
-
- // Which agg calls are used by our consumer?
- int j = groupCount + indicatorCount;
- int usedAggCallCount = 0;
- for (int i = 0; i < aggregate.getAggCallList().size(); i++) {
- if (fieldsUsed.get(j++)) {
- ++usedAggCallCount;
- }
- }
-
- // Offset due to the number of system fields having changed.
- Mapping mapping =
- Mappings.create(
- MappingType.INVERSE_SURJECTION,
- rowType.getFieldCount(),
- groupCount + indicatorCount + usedAggCallCount);
-
- final ImmutableBitSet newGroupSet =
- Mappings.apply(inputMapping, aggregate.getGroupSet());
-
- final ImmutableList<ImmutableBitSet> newGroupSets =
- ImmutableList.copyOf(
- Iterables.transform(aggregate.getGroupSets(),
- new Function<ImmutableBitSet, ImmutableBitSet>() {
- @Override
- public ImmutableBitSet apply(ImmutableBitSet input) {
- return Mappings.apply(inputMapping, input);
- }
- }));
-
- // Populate mapping of where to find the fields. System, group key and
- // indicator fields first.
- for (j = 0; j < groupCount + indicatorCount; j++) {
- mapping.set(j, j);
- }
-
- // Now create new agg calls, and populate mapping for them.
- final List<AggregateCall> newAggCallList = new ArrayList<>();
- j = groupCount + indicatorCount;
- for (AggregateCall aggCall : aggregate.getAggCallList()) {
- if (fieldsUsed.get(j)) {
- AggregateCall newAggCall =
- aggCall.copy(Mappings.apply2(inputMapping, aggCall.getArgList()),
- Mappings.apply(inputMapping, aggCall.filterArg));
- if (newAggCall.equals(aggCall)) {
- newAggCall = aggCall; // immutable -> canonize to save space
- }
- mapping.set(j, groupCount + indicatorCount + newAggCallList.size());
- newAggCallList.add(newAggCall);
- }
- ++j;
- }
-
- RelNode newAggregate = aggregateFactory.createAggregate(newInput,
- aggregate.indicator, newGroupSet, newGroupSets, newAggCallList);
-
- assert newAggregate.getClass() == aggregate.getClass();
-
- return new TrimResult(newAggregate, mapping);
- }
-
}
http://git-wip-us.apache.org/repos/asf/hive/blob/da4b1b07/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/ASTConverter.java
----------------------------------------------------------------------
diff --git a/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/ASTConverter.java b/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/ASTConverter.java
index e4ac154..d026e58 100644
--- a/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/ASTConverter.java
+++ b/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/ASTConverter.java
@@ -77,8 +77,7 @@ public class ASTConverter {
private Aggregate groupBy;
private Filter having;
private Project select;
- private Sort order;
- private Sort limit;
+ private Sort orderLimit;
private Schema schema;
@@ -203,27 +202,14 @@ public class ASTConverter {
* parent hence we need to go top down; but OB at each block really belong
* to its src/from. Hence the need to pass in sort for each block from
* its parent.
+ * 8. Limit
*/
- convertOBToASTNode((HiveSortLimit) order);
-
- // 8. Limit
- convertLimitToASTNode((HiveSortLimit) limit);
+ convertOrderLimitToASTNode((HiveSortLimit) orderLimit);
return hiveAST.getAST();
}
- private void convertLimitToASTNode(HiveSortLimit limit) {
- if (limit != null) {
- HiveSortLimit hiveLimit = limit;
- RexNode limitExpr = hiveLimit.getFetchExpr();
- if (limitExpr != null) {
- Object val = ((RexLiteral) limitExpr).getValue2();
- hiveAST.limit = ASTBuilder.limit(val);
- }
- }
- }
-
- private void convertOBToASTNode(HiveSortLimit order) {
+ private void convertOrderLimitToASTNode(HiveSortLimit order) {
if (order != null) {
HiveSortLimit hiveSortLimit = order;
if (!hiveSortLimit.getCollation().getFieldCollations().isEmpty()) {
@@ -264,6 +250,12 @@ public class ASTConverter {
}
hiveAST.order = orderAst;
}
+
+ RexNode limitExpr = hiveSortLimit.getFetchExpr();
+ if (limitExpr != null) {
+ Object val = ((RexLiteral) limitExpr).getValue2();
+ hiveAST.limit = ASTBuilder.limit(val);
+ }
}
}
@@ -366,11 +358,7 @@ public class ASTConverter {
if (ASTConverter.this.select != null) {
ASTConverter.this.from = node;
} else {
- Sort hiveSortRel = (Sort) node;
- if (hiveSortRel.getCollation().getFieldCollations().isEmpty())
- ASTConverter.this.limit = hiveSortRel;
- else
- ASTConverter.this.order = hiveSortRel;
+ ASTConverter.this.orderLimit = (Sort) node;
}
}
/*
http://git-wip-us.apache.org/repos/asf/hive/blob/da4b1b07/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/HiveOpConverter.java
----------------------------------------------------------------------
diff --git a/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/HiveOpConverter.java b/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/HiveOpConverter.java
index f0f8aa8..130ee89 100644
--- a/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/HiveOpConverter.java
+++ b/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/HiveOpConverter.java
@@ -487,7 +487,7 @@ public class HiveOpConverter {
if (this.semanticAnalyzer != null && semanticAnalyzer.getQB() != null
&& semanticAnalyzer.getQB().getParseInfo() != null)
this.semanticAnalyzer.getQB().getParseInfo().setOuterQueryLimit(limit);
- ArrayList<ColumnInfo> cinfoLst = createColInfos(inputOp);
+ ArrayList<ColumnInfo> cinfoLst = createColInfos(resultOp);
resultOp = OperatorFactory.getAndMakeChild(limitDesc,
new RowSchema(cinfoLst), resultOp);
@@ -1059,10 +1059,6 @@ public class HiveOpConverter {
}
private static JoinType extractJoinType(HiveJoin join) {
- // UNIQUE
- if (join.isDistinct()) {
- return JoinType.UNIQUE;
- }
// SEMIJOIN
if (join.isLeftSemiJoin()) {
return JoinType.LEFTSEMI;
@@ -1080,6 +1076,7 @@ public class HiveOpConverter {
resultJoinType = JoinType.RIGHTOUTER;
break;
default:
+ // TODO: UNIQUE JOIN
resultJoinType = JoinType.INNER;
break;
}
http://git-wip-us.apache.org/repos/asf/hive/blob/da4b1b07/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/PlanModifierForASTConv.java
----------------------------------------------------------------------
diff --git a/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/PlanModifierForASTConv.java b/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/PlanModifierForASTConv.java
index e820496..29e08f8 100644
--- a/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/PlanModifierForASTConv.java
+++ b/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/translator/PlanModifierForASTConv.java
@@ -312,7 +312,8 @@ public class PlanModifierForASTConv {
boolean validChild = true;
RelNode child = sortNode.getInput();
- if (!(HiveCalciteUtil.limitRelNode(sortNode) && HiveCalciteUtil.orderRelNode(child))
+ if (!(HiveCalciteUtil.limitRelNode(sortNode) && HiveCalciteUtil.orderRelNode(child)
+ && HiveCalciteUtil.limitRelNode(child))
&& !(child instanceof Project)) {
validChild = false;
}
http://git-wip-us.apache.org/repos/asf/hive/blob/da4b1b07/ql/src/java/org/apache/hadoop/hive/ql/parse/CalcitePlanner.java
----------------------------------------------------------------------
diff --git a/ql/src/java/org/apache/hadoop/hive/ql/parse/CalcitePlanner.java b/ql/src/java/org/apache/hadoop/hive/ql/parse/CalcitePlanner.java
index e13356c..de67b54 100644
--- a/ql/src/java/org/apache/hadoop/hive/ql/parse/CalcitePlanner.java
+++ b/ql/src/java/org/apache/hadoop/hive/ql/parse/CalcitePlanner.java
@@ -58,8 +58,6 @@ import org.apache.calcite.rel.core.AggregateCall;
import org.apache.calcite.rel.core.Filter;
import org.apache.calcite.rel.core.Join;
import org.apache.calcite.rel.core.JoinRelType;
-import org.apache.calcite.rel.core.Project;
-import org.apache.calcite.rel.core.Sort;
import org.apache.calcite.rel.metadata.CachingRelMetadataProvider;
import org.apache.calcite.rel.metadata.ChainedRelMetadataProvider;
import org.apache.calcite.rel.metadata.RelMetadataProvider;
@@ -902,7 +900,8 @@ public class CalcitePlanner extends SemanticAnalyzer {
HiveJoinToMultiJoinRule.INSTANCE, HiveProjectMergeRule.INSTANCE);
// The previous rules can pull up projections through join operators,
// thus we run the field trimmer again to push them back down
- HiveRelFieldTrimmer fieldTrimmer = new HiveRelFieldTrimmer(null, HiveProject.DEFAULT_PROJECT_FACTORY,
+ HiveRelFieldTrimmer fieldTrimmer = new HiveRelFieldTrimmer(null,
+ cluster, HiveProject.DEFAULT_PROJECT_FACTORY,
HiveFilter.DEFAULT_FILTER_FACTORY, HiveJoin.HIVE_JOIN_FACTORY,
HiveSemiJoin.HIVE_SEMIJOIN_FACTORY, HiveSortLimit.HIVE_SORT_REL_FACTORY,
HiveAggregate.HIVE_AGGR_REL_FACTORY, HiveUnion.UNION_REL_FACTORY);
@@ -983,7 +982,8 @@ public class CalcitePlanner extends SemanticAnalyzer {
new HivePartitionPruneRule(conf));
// 5. Projection Pruning
- HiveRelFieldTrimmer fieldTrimmer = new HiveRelFieldTrimmer(null, HiveProject.DEFAULT_PROJECT_FACTORY,
+ HiveRelFieldTrimmer fieldTrimmer = new HiveRelFieldTrimmer(null,
+ cluster, HiveProject.DEFAULT_PROJECT_FACTORY,
HiveFilter.DEFAULT_FILTER_FACTORY, HiveJoin.HIVE_JOIN_FACTORY,
HiveSemiJoin.HIVE_SEMIJOIN_FACTORY, HiveSortLimit.HIVE_SORT_REL_FACTORY,
HiveAggregate.HIVE_AGGR_REL_FACTORY, HiveUnion.UNION_REL_FACTORY);
http://git-wip-us.apache.org/repos/asf/hive/blob/da4b1b07/ql/src/test/results/clientpositive/bucketizedhiveinputformat.q.out
----------------------------------------------------------------------
diff --git a/ql/src/test/results/clientpositive/bucketizedhiveinputformat.q.out b/ql/src/test/results/clientpositive/bucketizedhiveinputformat.q.out
index 277b0f7..cfb95be 100644
--- a/ql/src/test/results/clientpositive/bucketizedhiveinputformat.q.out
+++ b/ql/src/test/results/clientpositive/bucketizedhiveinputformat.q.out
@@ -22,6 +22,8 @@ POSTHOOK: query: CREATE TABLE T2(name STRING) STORED AS SEQUENCEFILE
POSTHOOK: type: CREATETABLE
POSTHOOK: Output: database:default
POSTHOOK: Output: default@T2
+Warning: Shuffle Join JOIN[13][tables = [$hdt$_0, $hdt$_1, $hdt$_2]] in Stage 'Stage-2:MAPRED' is a cross product
+Warning: Shuffle Join JOIN[10][tables = [$hdt$_0, $hdt$_1]] in Stage 'Stage-1:MAPRED' is a cross product
PREHOOK: query: INSERT OVERWRITE TABLE T2 SELECT * FROM (
SELECT tmp1.name as name FROM (
SELECT name, 'MMM' AS n FROM T1) tmp1
http://git-wip-us.apache.org/repos/asf/hive/blob/da4b1b07/ql/src/test/results/clientpositive/spark/bucketizedhiveinputformat.q.out
----------------------------------------------------------------------
diff --git a/ql/src/test/results/clientpositive/spark/bucketizedhiveinputformat.q.out b/ql/src/test/results/clientpositive/spark/bucketizedhiveinputformat.q.out
index 98c5802..c8fc4d3 100644
--- a/ql/src/test/results/clientpositive/spark/bucketizedhiveinputformat.q.out
+++ b/ql/src/test/results/clientpositive/spark/bucketizedhiveinputformat.q.out
@@ -22,6 +22,8 @@ POSTHOOK: query: CREATE TABLE T2(name STRING) STORED AS SEQUENCEFILE
POSTHOOK: type: CREATETABLE
POSTHOOK: Output: database:default
POSTHOOK: Output: default@T2
+Warning: Shuffle Join JOIN[10][tables = [$hdt$_0, $hdt$_1]] in Work 'Reducer 2' is a cross product
+Warning: Shuffle Join JOIN[13][tables = [$hdt$_0, $hdt$_1, $hdt$_2]] in Work 'Reducer 3' is a cross product
PREHOOK: query: INSERT OVERWRITE TABLE T2 SELECT * FROM (
SELECT tmp1.name as name FROM (
SELECT name, 'MMM' AS n FROM T1) tmp1