/**
* Copyright (c) 2013, Institute of Information Systems (Sven Groppe and contributors of LUPOSDATE), University of Luebeck
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
* following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice, this list of conditions and the following
* disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
* following disclaimer in the documentation and/or other materials provided with the distribution.
* - Neither the name of the University of Luebeck nor the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package lupos.optimizations.physical.joinorder.costbasedoptimizer;
import lupos.engine.operators.index.BasicIndexScan;
import lupos.engine.operators.index.Root;
import lupos.optimizations.physical.joinorder.costbasedoptimizer.operatorgraphgenerator.QueryClientOperatorGraphGenerator;
/**
* This class is the cost-based optimizer for the QueryClient query evaluator.
*/
public class QueryClientCostBasedOptimizer extends CostBasedOptimizer {
/**
* Constructor
*/
public QueryClientCostBasedOptimizer() {
super(new QueryClientOperatorGraphGenerator());
}
/**
* Static method to call the cost-based optimizer for the QueryClient query evaluator
* @param indexScan the IndexScan operator with at least two triple patterns to join....
* @return the root operator under which the subgraph with the reordered joins are inserted
*/
public static Root rearrangeJoinOrder(final BasicIndexScan indexScan){
final Root newRoot = indexScan.getRoot().newInstance(indexScan.getRoot().dataset);
final QueryClientCostBasedOptimizer optimizer = new QueryClientCostBasedOptimizer();
optimizer.rearrangeJoinOrder(newRoot, indexScan);
return newRoot;
}
}