/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.hadoop.hive.ql.exec.vector.expressions.aggregates;
import org.apache.hadoop.hive.ql.exec.Description;
import org.apache.hadoop.hive.ql.exec.vector.VectorAggregationBufferRow;
import org.apache.hadoop.hive.ql.exec.vector.VectorizedRowBatch;
import org.apache.hadoop.hive.ql.exec.vector.expressions.VectorExpression;
import org.apache.hadoop.hive.ql.metadata.HiveException;
import org.apache.hadoop.hive.ql.plan.AggregationDesc;
import org.apache.hadoop.hive.ql.util.JavaDataModel;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorFactory;
import org.apache.hadoop.io.LongWritable;
/**
* VectorUDAFCountStar. Vectorized implementation for COUNT(*) aggregates.
*/
@Description(name = "count", value = "_FUNC_(expr) - Returns count(*) (vectorized)")
public class VectorUDAFCountStar extends VectorAggregateExpression {
private static final long serialVersionUID = 1L;
/**
* class for storing the current aggregate value.
*/
static class Aggregation implements AggregationBuffer {
private static final long serialVersionUID = 1L;
transient private long value;
transient private boolean isNull;
@Override
public int getVariableSize() {
throw new UnsupportedOperationException();
}
@Override
public void reset() {
isNull = true;
value = 0L;
}
}
transient private final LongWritable result;
public VectorUDAFCountStar(VectorExpression inputExpression) {
this();
}
public VectorUDAFCountStar() {
super();
result = new LongWritable(0);
}
private Aggregation getCurrentAggregationBuffer(
VectorAggregationBufferRow[] aggregationBufferSets,
int aggregateIndex,
int row) {
VectorAggregationBufferRow mySet = aggregationBufferSets[row];
Aggregation myagg = (Aggregation) mySet.getAggregationBuffer(aggregateIndex);
return myagg;
}
@Override
public void aggregateInputSelection(
VectorAggregationBufferRow[] aggregationBufferSets,
int aggregateIndex,
VectorizedRowBatch batch) throws HiveException {
int batchSize = batch.size;
if (batchSize == 0) {
return;
}
// count(*) cares not about NULLs nor selection
for (int i=0; i < batchSize; ++i) {
Aggregation myAgg = getCurrentAggregationBuffer(
aggregationBufferSets, aggregateIndex, i);
myAgg.isNull = false;
++myAgg.value;
}
}
@Override
public void aggregateInput(AggregationBuffer agg, VectorizedRowBatch batch)
throws HiveException {
int batchSize = batch.size;
if (batchSize == 0) {
return;
}
Aggregation myagg = (Aggregation)agg;
myagg.isNull = false;
myagg.value += batchSize;
}
@Override
public AggregationBuffer getNewAggregationBuffer() throws HiveException {
return new Aggregation();
}
@Override
public void reset(AggregationBuffer agg) throws HiveException {
Aggregation myAgg = (Aggregation) agg;
myAgg.reset();
}
@Override
public Object evaluateOutput(AggregationBuffer agg) throws HiveException {
Aggregation myagg = (Aggregation) agg;
if (myagg.isNull) {
return null;
}
else {
result.set (myagg.value);
return result;
}
}
@Override
public ObjectInspector getOutputObjectInspector() {
return PrimitiveObjectInspectorFactory.writableLongObjectInspector;
}
@Override
public int getAggregationBufferFixedSize() {
JavaDataModel model = JavaDataModel.get();
return JavaDataModel.alignUp(
model.object() +
model.primitive2() +
model.primitive1(),
model.memoryAlign());
}
@Override
public void init(AggregationDesc desc) throws HiveException {
// No-op
}
}