com.yahoo.sketches.hive.tuple.UnionArrayOfDoublesSketchUDAF Maven / Gradle / Ivy
/*
* Copyright 2016, Yahoo! Inc.
* Licensed under the terms of the Apache License 2.0. See LICENSE file at the project root for terms.
*/
package com.yahoo.sketches.hive.tuple;
import static com.yahoo.sketches.Util.DEFAULT_NOMINAL_ENTRIES;
import java.util.Arrays;
import org.apache.hadoop.hive.ql.exec.Description;
import org.apache.hadoop.hive.ql.exec.UDFArgumentException;
import org.apache.hadoop.hive.ql.exec.UDFArgumentTypeException;
import org.apache.hadoop.hive.ql.metadata.HiveException;
import org.apache.hadoop.hive.ql.parse.SemanticException;
import org.apache.hadoop.hive.ql.udf.generic.AbstractGenericUDAFResolver;
import org.apache.hadoop.hive.ql.udf.generic.GenericUDAFEvaluator;
import org.apache.hadoop.hive.ql.udf.generic.GenericUDAFParameterInfo;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspectorFactory;
import org.apache.hadoop.hive.serde2.objectinspector.PrimitiveObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.PrimitiveObjectInspector.PrimitiveCategory;
import org.apache.hadoop.hive.serde2.objectinspector.StructObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorFactory;
import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorUtils;
import com.yahoo.memory.Memory;
import com.yahoo.sketches.tuple.ArrayOfDoublesSketches;
@Description(
name = "UnionArrayOfDoublesSketch",
value = "_FUNC_(sketch, nominal number of entries, number of values)",
extended = "Returns an ArrayOfDoublesSketch as a binary blob that can be operated on by other"
+ " ArrayOfDoublesSketch related functions. "
+ "The nominal number of entries is optional, must be a power of 2,"
+ " does not have to match the input sketches, and controls the relative error expected"
+ " from the sketch. A number of 16384 can be expected to yield errors of roughly +-1.5% in"
+ " the estimation of uniques. The default number is defined in the sketches-core library,"
+ " and at the time of this writing was 4096 (about 3% error)."
+ " The number of values is optional and must match all input sketches (defaults to 1)")
public class UnionArrayOfDoublesSketchUDAF extends AbstractGenericUDAFResolver {
@Override
public GenericUDAFEvaluator getEvaluator(final GenericUDAFParameterInfo info) throws SemanticException {
final ObjectInspector[] inspectors = info.getParameterObjectInspectors();
if (inspectors.length < 1) {
throw new UDFArgumentException("Expected at least 1 argument");
}
if (inspectors.length > 3) {
throw new UDFArgumentTypeException(inspectors.length - 1, "Expected no more than 3 arguments");
}
ObjectInspectorValidator.validateGivenPrimitiveCategory(inspectors[0], 0, PrimitiveCategory.BINARY);
// nominal number of entries
if (inspectors.length > 1) {
ObjectInspectorValidator.validateIntegralParameter(inspectors[1], 1);
}
// number of double values per key
if (inspectors.length > 2) {
ObjectInspectorValidator.validateIntegralParameter(inspectors[2], 2);
}
return new UnionArrayOfDoublesSketchEvaluator();
}
public static class UnionArrayOfDoublesSketchEvaluator extends ArrayOfDoublesSketchEvaluator {
private static final int DEFAULT_NUM_VALUES = 1;
private PrimitiveObjectInspector sketchInspector_;
private PrimitiveObjectInspector numValuesInspector_;
@Override
public ObjectInspector init(final Mode mode, final ObjectInspector[] inspectors) throws HiveException {
super.init(mode, inspectors);
if (mode == Mode.PARTIAL1 || mode == Mode.COMPLETE) {
// input is original data
sketchInspector_ = (PrimitiveObjectInspector) inspectors[0];
if (inspectors.length > 1) {
nominalNumEntriesInspector_ = (PrimitiveObjectInspector) inspectors[1];
}
if (inspectors.length > 2) {
numValuesInspector_ = (PrimitiveObjectInspector) inspectors[2];
}
} else {
// input for PARTIAL2 and FINAL is the output from PARTIAL1
intermediateInspector_ = (StructObjectInspector) inspectors[0];
}
if (mode == Mode.PARTIAL1 || mode == Mode.PARTIAL2) {
// intermediate results need to include the the nominal number of entries and number of values
return ObjectInspectorFactory.getStandardStructObjectInspector(
Arrays.asList(NOMINAL_NUM_ENTRIES_FIELD, NUM_VALUES_FIELD, SKETCH_FIELD),
Arrays.asList(
PrimitiveObjectInspectorFactory.getPrimitiveWritableObjectInspector(PrimitiveCategory.INT),
PrimitiveObjectInspectorFactory.getPrimitiveWritableObjectInspector(PrimitiveCategory.INT),
PrimitiveObjectInspectorFactory.getPrimitiveWritableObjectInspector(PrimitiveCategory.BINARY)
)
);
}
// final results include just the sketch
return PrimitiveObjectInspectorFactory.getPrimitiveWritableObjectInspector(PrimitiveCategory.BINARY);
}
@Override
public void iterate(final @SuppressWarnings("deprecation") AggregationBuffer buf, final Object[] data)
throws HiveException {
if (data[0] == null) { return; }
final ArrayOfDoublesUnionState state = (ArrayOfDoublesUnionState) buf;
if (!state.isInitialized()) {
initializeState(state, data);
}
final byte[] serializedSketch = (byte[]) sketchInspector_.getPrimitiveJavaObject(data[0]);
if (serializedSketch == null) { return; }
state.update(ArrayOfDoublesSketches.wrapSketch(Memory.wrap(serializedSketch)));
}
private void initializeState(final ArrayOfDoublesUnionState state, final Object[] data) {
int nominalNumEntries = DEFAULT_NOMINAL_ENTRIES;
if (nominalNumEntriesInspector_ != null) {
nominalNumEntries = PrimitiveObjectInspectorUtils.getInt(data[1], nominalNumEntriesInspector_);
}
int numValues = DEFAULT_NUM_VALUES;
if (numValuesInspector_ != null) {
numValues = PrimitiveObjectInspectorUtils.getInt(data[2], numValuesInspector_);
}
state.init(nominalNumEntries, numValues);
}
@SuppressWarnings("deprecation")
@Override
public AggregationBuffer getNewAggregationBuffer() throws HiveException {
return new ArrayOfDoublesUnionState();
}
}
}