/* * 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.datasketches.hive.theta; import static org.apache.datasketches.Util.DEFAULT_NOMINAL_ENTRIES; import static org.apache.datasketches.Util.DEFAULT_UPDATE_SEED; import java.util.Arrays; import org.apache.datasketches.memory.Memory; 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.StandardStructObjectInspector; import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorFactory; import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorUtils; /** * Hive UDAF to compute union of theta Sketch objects */ @Description( name = "unionSketch", value = "_FUNC_(sketch, size, seed) - Compute the union of sketches of given size and seed", extended = "Example:\n" + "> SELECT UnionSketch(sketch, 16384) FROM src;\n" + "The return value is a binary blob that contains a compact sketch, which can " + "be operated on by the other sketch-related functions. The optional " + "size must be a power of 2, and controls the relative error of the expected " + "result. A size of 16384 can be expected to yeild errors of roughly +-1.5% " + "in the estimation of uniques with 95% confidence. " + "The default size is defined in the sketches-core library and at the time of this writing " + "was 4096 (about 3% error). " + "The seed is optional, and using it is not recommended unless you really know why you need it") public class UnionSketchUDAF extends AbstractGenericUDAFResolver { /** * Perform argument count check and argument type checking, returns an * appropriate evaluator to perform based on input type (which should always * be BINARY sketch). Also check sketch size and seed params if they are passed in. * * @see org.apache.hadoop.hive.ql.udf.generic.AbstractGenericUDAFResolver * #getEvaluator(org.apache.hadoop.hive.ql.udf.generic.GenericUDAFParameterInfo) * * @param info The parameter info to validate * @return The GenericUDAFEvaluator to use to compute the function. */ @Override public GenericUDAFEvaluator getEvaluator(final GenericUDAFParameterInfo info) throws SemanticException { final ObjectInspector[] parameters = info.getParameterObjectInspectors(); if (parameters.length < 1) { throw new UDFArgumentException("Please specify at least 1 argument"); } if (parameters.length > 3) { throw new UDFArgumentTypeException(parameters.length - 1, "Please specify no more than 3 arguments"); } ObjectInspectorValidator.validateGivenPrimitiveCategory(parameters[0], 0, PrimitiveCategory.BINARY); if (parameters.length > 1) { ObjectInspectorValidator.validateIntegralParameter(parameters[1], 1); } if (parameters.length > 2) { ObjectInspectorValidator.validateIntegralParameter(parameters[2], 2); } return new UnionSketchUDAFEvaluator(); } /** * Evaluator class of Generic UDAF, main logic of our UDAF. * */ public static class UnionSketchUDAFEvaluator extends UnionEvaluator { /** * Receives the passed in argument object inspectors and returns the desired * return type's object inspector to inform hive of return type of UDAF. * * @param mode * Mode (i.e. PARTIAL 1, COMPLETE...) for determining input/output * object inspector type. * @param parameters * List of object inspectors for input arguments. * @return The object inspector type indicates the UDAF return type (i.e. * returned type of terminate(...)). */ @Override public ObjectInspector init(final Mode mode, final ObjectInspector[] parameters) throws HiveException { super.init(mode, parameters); if (mode == Mode.PARTIAL1 || mode == Mode.COMPLETE) { inputObjectInspector = (PrimitiveObjectInspector) parameters[0]; if (parameters.length > 1) { nominalEntriesObjectInspector = (PrimitiveObjectInspector) parameters[1]; } if (parameters.length > 2) { seedObjectInspector = (PrimitiveObjectInspector) parameters[2]; } } else { // mode = partial2 || final intermediateObjectInspector = (StandardStructObjectInspector) parameters[0]; } if (mode == Mode.PARTIAL1 || mode == Mode.PARTIAL2) { // intermediate results need to include the nominal number of entries and the seed return ObjectInspectorFactory.getStandardStructObjectInspector( Arrays.asList(NOMINAL_ENTRIES_FIELD, SEED_FIELD, SKETCH_FIELD), Arrays.asList( PrimitiveObjectInspectorFactory.getPrimitiveWritableObjectInspector(PrimitiveCategory.INT), PrimitiveObjectInspectorFactory.getPrimitiveWritableObjectInspector(PrimitiveCategory.LONG), PrimitiveObjectInspectorFactory.getPrimitiveWritableObjectInspector(PrimitiveCategory.BINARY) ) ); } // final results include just the sketch return PrimitiveObjectInspectorFactory.getPrimitiveWritableObjectInspector(PrimitiveCategory.BINARY); } /** * Add the incoming sketch into the internal state. * * @param agg * aggregation buffer storing intermediate results. * @param parameters * sketches in the form of Object passed in to be merged. */ @Override public void iterate(final @SuppressWarnings("deprecation") AggregationBuffer agg, final Object[] parameters) throws HiveException { if (parameters[0] == null) { return; } final UnionState state = (UnionState) agg; if (!state.isInitialized()) { initializeState(state, parameters); } final byte[] serializedSketch = (byte[]) inputObjectInspector.getPrimitiveJavaObject(parameters[0]); if (serializedSketch == null) { return; } state.update(Memory.wrap(serializedSketch)); } private void initializeState(final UnionState state, final Object[] parameters) { int nominalEntries = DEFAULT_NOMINAL_ENTRIES; if (nominalEntriesObjectInspector != null) { nominalEntries = PrimitiveObjectInspectorUtils.getInt(parameters[1], nominalEntriesObjectInspector); } long seed = DEFAULT_UPDATE_SEED; if (seedObjectInspector != null) { seed = PrimitiveObjectInspectorUtils.getLong(parameters[2], seedObjectInspector); } state.init(nominalEntries, seed); } } }