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* regarding copyright ownership. Some portions may be licensed
* to Red Hat, Inc. under one or more contributor license agreements.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
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package org.teiid.query.optimizer.relational.rules;
import org.teiid.api.exception.query.ExpressionEvaluationException;
import org.teiid.api.exception.query.QueryPlannerException;
import org.teiid.common.buffer.BlockedException;
import org.teiid.core.TeiidComponentException;
import org.teiid.query.analysis.AnalysisRecord;
import org.teiid.query.eval.Evaluator;
import org.teiid.query.metadata.QueryMetadataInterface;
import org.teiid.query.optimizer.capabilities.CapabilitiesFinder;
import org.teiid.query.optimizer.relational.OptimizerRule;
import org.teiid.query.optimizer.relational.RuleStack;
import org.teiid.query.optimizer.relational.plantree.NodeConstants;
import org.teiid.query.optimizer.relational.plantree.NodeEditor;
import org.teiid.query.optimizer.relational.plantree.PlanNode;
import org.teiid.query.sql.lang.Criteria;
import org.teiid.query.sql.visitor.EvaluatableVisitor;
import org.teiid.query.util.CommandContext;
/**
* Removes phantom and TRUE or FALSE criteria
*/
public final class RuleCleanCriteria implements OptimizerRule {
/**
* @see OptimizerRule#execute(PlanNode, QueryMetadataInterface, RuleStack)
*/
public PlanNode execute(PlanNode plan, QueryMetadataInterface metadata, CapabilitiesFinder capFinder, RuleStack rules, AnalysisRecord analysisRecord, CommandContext context)
throws QueryPlannerException, TeiidComponentException {
boolean pushRaiseNull = false;
for (PlanNode critNode : NodeEditor.findAllNodes(plan, NodeConstants.Types.SELECT)) {
if (critNode.hasBooleanProperty(NodeConstants.Info.IS_PHANTOM)) {
NodeEditor.removeChildNode(critNode.getParent(), critNode);
continue;
}
//TODO: remove dependent set criteria that has not been meaningfully pushed from its parent join
if (critNode.hasBooleanProperty(NodeConstants.Info.IS_HAVING) || critNode.getGroups().size() != 0) {
continue;
}
Criteria crit = (Criteria)critNode.getProperty(NodeConstants.Info.SELECT_CRITERIA);
//if not evaluatable, just move on to the next criteria
if (!EvaluatableVisitor.isFullyEvaluatable(crit, true)) {
continue;
}
//if evaluatable
try {
boolean eval = Evaluator.evaluate(crit);
if(eval) {
NodeEditor.removeChildNode(critNode.getParent(), critNode);
} else {
FrameUtil.replaceWithNullNode(critNode);
pushRaiseNull = true;
}
//none of the following exceptions should ever occur
} catch(BlockedException e) {
throw new TeiidComponentException(e);
} catch (ExpressionEvaluationException e) {
throw new TeiidComponentException(e);
}
}
if (pushRaiseNull) {
rules.push(RuleConstants.RAISE_NULL);
}
return plan;
}
public String toString() {
return "CleanCriteria"; //$NON-NLS-1$
}
}