/* This file is part of VoltDB.
* Copyright (C) 2008-2010 VoltDB L.L.C.
*
* VoltDB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* VoltDB 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with VoltDB. If not, see <http://www.gnu.org/licenses/>.
*/
package org.voltdb.plannodes;
import java.util.ArrayList;
import org.json.JSONException;
import org.json.JSONObject;
import org.json.JSONStringer;
import org.voltdb.catalog.Cluster;
import org.voltdb.catalog.Database;
import org.voltdb.compiler.DatabaseEstimates;
import org.voltdb.compiler.ScalarValueHints;
import org.voltdb.expressions.AbstractExpression;
import org.voltdb.planner.PlanColumn;
import org.voltdb.planner.PlanStatistics;
import org.voltdb.planner.PlannerContext;
import org.voltdb.types.PlanNodeType;
/**
*
*/
public class ProjectionPlanNode extends AbstractPlanNode {
/**
* @param id
*/
public ProjectionPlanNode(PlannerContext context, Integer id) {
super(context, id);
}
@Override
public PlanNodeType getPlanNodeType() {
return PlanNodeType.PROJECTION;
}
@Override
public void validate() throws Exception {
super.validate();
// Validate Expression Trees
for (int ctr = 0; ctr < m_outputColumns.size(); ctr++) {
PlanColumn column = m_context.get(m_outputColumns.get(ctr));
AbstractExpression exp = column.getExpression();
if (exp == null) {
throw new Exception("ERROR: The Output Column Expression at position '" + ctr + "' is NULL");
}
exp.validate();
}
}
public void appendOutputColumn(PlanColumn column)
{
m_outputColumns.add(column.guid());
}
@SuppressWarnings("unchecked")
@Override
protected ArrayList<Integer> createOutputColumns(Database db, ArrayList<Integer> input) {
return (ArrayList<Integer>)m_outputColumns.clone();
}
@Override
public boolean computeEstimatesRecursively(PlanStatistics stats,
Cluster cluster, Database db, DatabaseEstimates estimates, ScalarValueHints[] paramHints) {
// TODO Auto-generated method stub
return super.computeEstimatesRecursively(stats, cluster, db, estimates, paramHints);
}
@Override
public void toJSONString(JSONStringer stringer) throws JSONException {
super.toJSONString(stringer);
}
@Override
protected void loadFromJSONObject(JSONObject obj, Database db) throws JSONException {
// Nothing to do???
}
}