/**
* 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.translator;
import java.util.ArrayList;
import java.util.List;
import org.apache.calcite.rel.RelNode;
import org.apache.calcite.rel.core.Project;
import org.apache.calcite.rex.RexNode;
import org.apache.calcite.util.Pair;
import org.apache.hadoop.hive.metastore.api.FieldSchema;
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.reloperators.HiveProject;
public class PlanModifierForReturnPath {
public static RelNode convertOpTree(RelNode rel, List<FieldSchema> resultSchema, boolean isCTAS)
throws CalciteSemanticException {
if (isCTAS) {
rel = introduceProjectIfNeeded(rel, resultSchema);
}
RelNode newTopNode = rel;
Pair<RelNode, RelNode> topSelparentPair = HiveCalciteUtil.getTopLevelSelect(newTopNode);
PlanModifierUtil.fixTopOBSchema(newTopNode, topSelparentPair, resultSchema, false);
return newTopNode;
}
private static RelNode introduceProjectIfNeeded(RelNode optimizedOptiqPlan,
List<FieldSchema> resultSchema) throws CalciteSemanticException {
List<String> fieldNames = new ArrayList<>();
for (FieldSchema fieldSchema : resultSchema) {
fieldNames.add(fieldSchema.getName());
}
RelNode newRoot = null;
List<RexNode> projectList = null;
if (!(optimizedOptiqPlan instanceof Project)) {
projectList = HiveCalciteUtil.getProjsFromBelowAsInputRef(optimizedOptiqPlan);
newRoot = HiveProject.create(optimizedOptiqPlan, projectList, fieldNames);
} else {
HiveProject project = (HiveProject) optimizedOptiqPlan;
newRoot = HiveProject.create(project.getInput(0), project.getChildExps(), fieldNames);
}
return newRoot;
}
}