/**
* Copyright (C) 2009-2013 FoundationDB, LLC
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package com.foundationdb.sql.optimizer.plan;
import com.foundationdb.server.types.TInstance;
import com.foundationdb.sql.types.DataTypeDescriptor;
import com.foundationdb.sql.parser.ValueNode;
/** An expression evaluated by a subquery: first column of first row
* or <code>NULL</code>.
*/
public class SubqueryValueExpression extends SubqueryExpression
{
public SubqueryValueExpression(Subquery subquery,
DataTypeDescriptor sqlType, ValueNode sqlSource,
TInstance type) {
super(subquery, sqlType, sqlSource, type);
}
@Override
public boolean equals(Object obj) {
if (!(obj instanceof SubqueryValueExpression)) return false;
SubqueryValueExpression other = (SubqueryValueExpression)obj;
// Currently this is ==; don't match whole subquery.
return getSubquery().equals(other.getSubquery());
}
@Override
public int hashCode() {
return getSubquery().hashCode();
}
}