/**
* 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.calcite.rules;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import org.apache.calcite.plan.RelOptRule;
import org.apache.calcite.plan.RelOptRuleCall;
import org.apache.calcite.plan.hep.HepRelVertex;
import org.apache.calcite.rel.RelDistribution;
import org.apache.calcite.rel.RelFieldCollation;
import org.apache.calcite.rel.RelNode;
import org.apache.calcite.rel.core.Exchange;
import org.apache.calcite.rel.core.Join;
import org.apache.calcite.rex.RexNode;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.hadoop.hive.ql.optimizer.calcite.CalciteSemanticException;
import org.apache.hadoop.hive.ql.optimizer.calcite.HiveCalciteUtil;
import org.apache.hadoop.hive.ql.optimizer.calcite.HiveCalciteUtil.JoinLeafPredicateInfo;
import org.apache.hadoop.hive.ql.optimizer.calcite.HiveCalciteUtil.JoinPredicateInfo;
import org.apache.hadoop.hive.ql.optimizer.calcite.HiveRelCollation;
import org.apache.hadoop.hive.ql.optimizer.calcite.HiveRelDistribution;
import org.apache.hadoop.hive.ql.optimizer.calcite.reloperators.HiveJoin;
import org.apache.hadoop.hive.ql.optimizer.calcite.reloperators.HiveMultiJoin;
import org.apache.hadoop.hive.ql.optimizer.calcite.reloperators.HiveSortExchange;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Sets;
/** Not an optimization rule.
* Rule to aid in translation from Calcite tree -> Hive tree.
* Transforms :
* Left Right Left Right
* \ / -> \ /
* Join HashExchange HashExchange
* \ /
* Join
*/
public class HiveInsertExchange4JoinRule extends RelOptRule {
protected static transient final Logger LOG = LoggerFactory
.getLogger(HiveInsertExchange4JoinRule.class);
/** Rule that creates Exchange operators under a MultiJoin operator. */
public static final HiveInsertExchange4JoinRule EXCHANGE_BELOW_MULTIJOIN =
new HiveInsertExchange4JoinRule(HiveMultiJoin.class);
/** Rule that creates Exchange operators under a Join operator. */
public static final HiveInsertExchange4JoinRule EXCHANGE_BELOW_JOIN =
new HiveInsertExchange4JoinRule(Join.class);
public HiveInsertExchange4JoinRule(Class<? extends RelNode> clazz) {
// match multijoin or join
super(RelOptRule.operand(clazz, any()));
}
@Override
public void onMatch(RelOptRuleCall call) {
JoinPredicateInfo joinPredInfo;
if (call.rel(0) instanceof HiveMultiJoin) {
HiveMultiJoin multiJoin = call.rel(0);
joinPredInfo = multiJoin.getJoinPredicateInfo();
} else if (call.rel(0) instanceof HiveJoin) {
HiveJoin hiveJoin = call.rel(0);
joinPredInfo = hiveJoin.getJoinPredicateInfo();
} else if (call.rel(0) instanceof Join) {
Join join = call.rel(0);
try {
joinPredInfo = HiveCalciteUtil.JoinPredicateInfo.constructJoinPredicateInfo(join);
} catch (CalciteSemanticException e) {
throw new RuntimeException(e);
}
} else {
return;
}
for (RelNode child : call.rel(0).getInputs()) {
if (((HepRelVertex)child).getCurrentRel() instanceof Exchange) {
return;
}
}
// Get key columns from inputs. Those are the columns on which we will distribute on.
// It is also the columns we will sort on.
List<RelNode> newInputs = new ArrayList<RelNode>();
for (int i=0; i<call.rel(0).getInputs().size(); i++) {
List<Integer> joinKeyPositions = new ArrayList<Integer>();
ImmutableList.Builder<RexNode> joinExprsBuilder = new ImmutableList.Builder<RexNode>();
Set<String> keySet = Sets.newHashSet();
ImmutableList.Builder<RelFieldCollation> collationListBuilder =
new ImmutableList.Builder<RelFieldCollation>();
for (int j = 0; j < joinPredInfo.getEquiJoinPredicateElements().size(); j++) {
JoinLeafPredicateInfo joinLeafPredInfo = joinPredInfo.
getEquiJoinPredicateElements().get(j);
for (RexNode joinExprNode : joinLeafPredInfo.getJoinExprs(i)) {
if (keySet.add(joinExprNode.toString())) {
joinExprsBuilder.add(joinExprNode);
}
}
for (int pos : joinLeafPredInfo.getProjsJoinKeysInChildSchema(i)) {
if (!joinKeyPositions.contains(pos)) {
joinKeyPositions.add(pos);
collationListBuilder.add(new RelFieldCollation(pos));
}
}
}
HiveSortExchange exchange = HiveSortExchange.create(call.rel(0).getInput(i),
new HiveRelDistribution(RelDistribution.Type.HASH_DISTRIBUTED, joinKeyPositions),
new HiveRelCollation(collationListBuilder.build()),
joinExprsBuilder.build());
newInputs.add(exchange);
}
RelNode newOp;
if (call.rel(0) instanceof HiveMultiJoin) {
HiveMultiJoin multiJoin = call.rel(0);
newOp = multiJoin.copy(multiJoin.getTraitSet(), newInputs);
} else if (call.rel(0) instanceof Join) {
Join join = call.rel(0);
newOp = join.copy(join.getTraitSet(), join.getCondition(),
newInputs.get(0), newInputs.get(1), join.getJoinType(),
join.isSemiJoinDone());
} else {
return;
}
call.getPlanner().onCopy(call.rel(0), newOp);
call.transformTo(newOp);
}
}