| /* |
| * 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.hll; |
| |
| import java.util.Arrays; |
| |
| import org.apache.datasketches.hll.TgtHllType; |
| 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.ObjectInspectorUtils; |
| 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; |
| |
| /** |
| * Hive UDAF to create an HllSketch from raw data. |
| */ |
| @Description( |
| name = "dataToSketch", |
| value = "_FUNC_(expr, lgK, type) - " |
| + "Compute a sketch on data 'expr' with given parameters lgK and target type", |
| extended = "Example:\n" |
| + "> SELECT dataToSketch(val, 12) FROM src;\n" |
| + "The return value is a binary blob that can be operated on by other sketch related functions." |
| + " The lgK parameter controls the sketch size and rlative error expected from the sketch." |
| + " It is optional and must be from 4 to 21. The default is 12, which is expected to yield errors" |
| + " of roughly +-3% in the estimation of uniques with 95% confidence." |
| + " The target type parameter is optional and must be 'HLL_4', 'HLL_6' or 'HLL_8'." |
| + " The default is 'HLL_4'") |
| @SuppressWarnings("javadoc") |
| public class DataToSketchUDAF extends AbstractGenericUDAFResolver { |
| |
| /** |
| * Performs argument number and type validation. DataToSketch expects |
| * to receive between one and three arguments. |
| * <ul> |
| * <li>The first (required) is the value to add to the sketch and must be a primitive.</li> |
| * |
| * <li>The second (optional) is the lgK from 4 to 21 (default 12). |
| * This must be an integral value and must be constant.</li> |
| * |
| * <li>The third (optional) is the target HLL type and must be a string 'HLL_4', |
| * 'HLL_6' or 'HLL_8' (default 'HLL_4').</li> |
| * </ul> |
| * |
| * @see org.apache.hadoop.hive.ql.udf.generic.AbstractGenericUDAFResolver |
| * #getEvaluator(org.apache.hadoop.hive.ql.udf.generic.GenericUDAFParameterInfo) |
| * |
| * @param info Parameter info to validate |
| * @return The GenericUDAFEvaluator that should be used to calculate the function. |
| */ |
| @Override |
| public GenericUDAFEvaluator getEvaluator(final GenericUDAFParameterInfo info) throws SemanticException { |
| final ObjectInspector[] inspectors = info.getParameterObjectInspectors(); |
| |
| // Validate the correct number of parameters |
| if (inspectors.length < 1) { |
| throw new UDFArgumentException("Please specify at least 1 argument"); |
| } |
| |
| if (inspectors.length > 3) { |
| throw new UDFArgumentException("Please specify no more than 3 arguments"); |
| } |
| |
| // Validate first parameter type |
| ObjectInspectorValidator.validateCategoryPrimitive(inspectors[0], 0); |
| |
| // Validate second argument if present |
| if (inspectors.length > 1) { |
| ObjectInspectorValidator.validateIntegralParameter(inspectors[1], 1); |
| if (!ObjectInspectorUtils.isConstantObjectInspector(inspectors[1])) { |
| throw new UDFArgumentTypeException(1, "The second argument must be a constant"); |
| } |
| } |
| |
| // Validate third argument if present |
| if (inspectors.length > 2) { |
| ObjectInspectorValidator.validateGivenPrimitiveCategory(inspectors[2], 2, PrimitiveCategory.STRING); |
| if (!ObjectInspectorUtils.isConstantObjectInspector(inspectors[2])) { |
| throw new UDFArgumentTypeException(2, "The third argument must be a constant"); |
| } |
| } |
| |
| return new DataToSketchEvaluator(); |
| } |
| |
| public static class DataToSketchEvaluator extends SketchEvaluator { |
| |
| private Mode mode_; |
| |
| @SuppressWarnings("deprecation") |
| @Override |
| public AggregationBuffer getNewAggregationBuffer() throws HiveException { |
| // Different State is used for the iterate phase and the merge phase. |
| // A user reported that in some version of Hive this was apparently called before init, |
| // so the mode_ was null. A solution was implemented to have UnionState, which can work |
| // in both cases, but SketchState is more space-efficient. |
| // HLL sketch is about compactness, so let's use SketchState if possible. |
| if (mode_ == Mode.PARTIAL1 || mode_ == Mode.COMPLETE) { // iterate() will be used |
| return new SketchState(); |
| } |
| return new UnionState(); |
| } |
| |
| /* |
| * (non-Javadoc) |
| * |
| * @see |
| * org.apache.hadoop.hive.ql.udf.generic.GenericUDAFEvaluator#init(org.apache |
| * .hadoop.hive.ql.udf.generic.GenericUDAFEvaluator.Mode, |
| * org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector[]) |
| */ |
| @Override |
| public ObjectInspector init(final Mode mode, final ObjectInspector[] parameters) throws HiveException { |
| super.init(mode, parameters); |
| mode_ = mode; |
| if (mode == Mode.PARTIAL1 || mode == Mode.COMPLETE) { |
| // input is original data |
| inputInspector_ = (PrimitiveObjectInspector) parameters[0]; |
| if (parameters.length > 1) { |
| lgKInspector_ = (PrimitiveObjectInspector) parameters[1]; |
| } |
| if (parameters.length > 2) { |
| hllTypeInspector_ = (PrimitiveObjectInspector) parameters[2]; |
| } |
| } else { |
| // input for PARTIAL2 and FINAL is the output from PARTIAL1 |
| intermediateInspector_ = (StructObjectInspector) parameters[0]; |
| } |
| |
| if (mode == Mode.PARTIAL1 || mode == Mode.PARTIAL2) { |
| // intermediate results need to include the lgK and the target HLL type |
| return ObjectInspectorFactory.getStandardStructObjectInspector( |
| Arrays.asList(LG_K_FIELD, HLL_TYPE_FIELD, SKETCH_FIELD), |
| Arrays.asList( |
| PrimitiveObjectInspectorFactory.getPrimitiveWritableObjectInspector(PrimitiveCategory.INT), |
| PrimitiveObjectInspectorFactory.getPrimitiveWritableObjectInspector(PrimitiveCategory.STRING), |
| PrimitiveObjectInspectorFactory.getPrimitiveWritableObjectInspector(PrimitiveCategory.BINARY) |
| ) |
| ); |
| } |
| // final results include just the sketch |
| return PrimitiveObjectInspectorFactory.getPrimitiveWritableObjectInspector(PrimitiveCategory.BINARY); |
| } |
| |
| /* |
| * (non-Javadoc) |
| * |
| * @see |
| * org.apache.hadoop.hive.ql.udf.generic.GenericUDAFEvaluator#iterate(org |
| * .apache |
| * .hadoop.hive.ql.udf.generic.GenericUDAFEvaluator.AggregationBuffer, |
| * java.lang.Object[]) |
| */ |
| @Override |
| public void iterate(final @SuppressWarnings("deprecation") AggregationBuffer agg, |
| final Object[] parameters) throws HiveException { |
| if (parameters[0] == null) { return; } |
| final State state = (State) agg; |
| if (!state.isInitialized()) { |
| initializeState(state, parameters); |
| } |
| state.update(parameters[0], inputInspector_); |
| } |
| |
| private void initializeState(final State state, final Object[] parameters) { |
| int lgK = DEFAULT_LG_K; |
| if (lgKInspector_ != null) { |
| lgK = PrimitiveObjectInspectorUtils.getInt(parameters[1], lgKInspector_); |
| } |
| TgtHllType type = DEFAULT_HLL_TYPE; |
| if (hllTypeInspector_ != null) { |
| type = TgtHllType.valueOf(PrimitiveObjectInspectorUtils.getString(parameters[2], hllTypeInspector_)); |
| } |
| state.init(lgK, type); |
| } |
| |
| } |
| |
| } |