/*
* 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.operator;
import com.facebook.presto.Session;
import com.facebook.presto.spi.Page;
import com.facebook.presto.spi.PageBuilder;
import com.facebook.presto.spi.type.Type;
import com.facebook.presto.sql.gen.JoinCompiler;
import java.util.List;
import java.util.Optional;
import static com.facebook.presto.SystemSessionProperties.isDictionaryAggregationEnabled;
import static com.facebook.presto.spi.type.BigintType.BIGINT;
public interface GroupByHash
{
static GroupByHash createGroupByHash(
Session session,
List<? extends Type> hashTypes,
int[] hashChannels,
Optional<Integer> inputHashChannel,
int expectedSize,
JoinCompiler joinCompiler)
{
return createGroupByHash(hashTypes, hashChannels, inputHashChannel, expectedSize, isDictionaryAggregationEnabled(session), joinCompiler);
}
static GroupByHash createGroupByHash(
List<? extends Type> hashTypes,
int[] hashChannels,
Optional<Integer> inputHashChannel,
int expectedSize,
boolean processDictionary,
JoinCompiler joinCompiler)
{
if (hashTypes.size() == 1 && hashTypes.get(0).equals(BIGINT) && hashChannels.length == 1) {
return new BigintGroupByHash(hashChannels[0], inputHashChannel.isPresent(), expectedSize);
}
return new MultiChannelGroupByHash(hashTypes, hashChannels, inputHashChannel, expectedSize, processDictionary, joinCompiler);
}
long getEstimatedSize();
long getHashCollisions();
double getExpectedHashCollisions();
List<Type> getTypes();
int getGroupCount();
void appendValuesTo(int groupId, PageBuilder pageBuilder, int outputChannelOffset);
void addPage(Page page);
GroupByIdBlock getGroupIds(Page page);
boolean contains(int position, Page page, int[] hashChannels);
int putIfAbsent(int position, Page page);
long getRawHash(int groupyId);
}