/*
* Licensed 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 com.facebook.presto.tpch;
import com.facebook.presto.spi.Index;
import com.facebook.presto.spi.RecordSet;
import com.google.common.base.Function;
import static com.facebook.presto.tpch.TpchIndexedData.IndexedTable;
import static com.google.common.base.Preconditions.checkNotNull;
public class TpchIndex
implements Index
{
private final Function<RecordSet, RecordSet> keyFormatter;
private final Function<RecordSet, RecordSet> outputFormatter;
private final IndexedTable indexedTable;
public TpchIndex(Function<RecordSet, RecordSet> keyFormatter, Function<RecordSet, RecordSet> outputFormatter, IndexedTable indexedTable)
{
this.keyFormatter = checkNotNull(keyFormatter, "keyFormatter is null");
this.outputFormatter = checkNotNull(outputFormatter, "outputFormatter is null");
this.indexedTable = checkNotNull(indexedTable, "indexedTable is null");
}
@Override
public RecordSet lookup(RecordSet rawInputRecordSet)
{
// convert the input record set from the column ordering in the query to
// match the column ordering of the index
RecordSet inputRecordSet = keyFormatter.apply(rawInputRecordSet);
// lookup the values in the index
RecordSet rawOutputRecordSet = indexedTable.lookupKeys(inputRecordSet);
// convert the output record set of the index into the column ordering
// expect by the query
return outputFormatter.apply(rawOutputRecordSet);
}
}