| /* |
| * 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.HllSketch; |
| import org.apache.datasketches.hll.TgtHllType; |
| 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.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.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 HllSketch objects |
| */ |
| @Description( |
| name = "unionSketch", |
| value = "_FUNC_(sketch, lgK, type) - Compute the union of sketches of given size and seed", |
| extended = "Example:\n" |
| + "> SELECT UnionSketch(sketch) 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'") |
| 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 lgK and target HLL type parameters 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[] inspectors = info.getParameterObjectInspectors(); |
| |
| if (inspectors.length < 1) { |
| throw new UDFArgumentException("Please specify at least 1 argument"); |
| } |
| |
| if (inspectors.length > 3) { |
| throw new UDFArgumentTypeException(inspectors.length - 1, "Please specify no more than 3 arguments"); |
| } |
| |
| ObjectInspectorValidator.validateGivenPrimitiveCategory(inspectors[0], 0, PrimitiveCategory.BINARY); |
| |
| // 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 UnionSketchUDAFEvaluator(); |
| } |
| |
| /** |
| * Evaluator class, main logic of our UDAF. |
| * |
| */ |
| public static class UnionSketchUDAFEvaluator extends SketchEvaluator { |
| |
| @SuppressWarnings("deprecation") |
| @Override |
| public AggregationBuffer getNewAggregationBuffer() throws HiveException { |
| return new UnionState(); |
| } |
| |
| /** |
| * 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 and 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) { |
| inputInspector_ = (PrimitiveObjectInspector) parameters[0]; |
| if (parameters.length > 1) { |
| lgKInspector_ = (PrimitiveObjectInspector) parameters[1]; |
| } |
| if (parameters.length > 2) { |
| hllTypeInspector_ = (PrimitiveObjectInspector) parameters[2]; |
| } |
| } else { |
| // mode = partial2 || final |
| intermediateInspector_ = (StandardStructObjectInspector) 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); |
| } |
| |
| /** |
| * Add the incoming sketch into the internal state. |
| * |
| * @param buf |
| * 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 buf, |
| final Object[] parameters) throws HiveException { |
| if (parameters[0] == null) { return; } |
| final UnionState state = (UnionState) buf; |
| if (!state.isInitialized()) { |
| initializeState(state, parameters); |
| } |
| final byte[] serializedSketch = (byte[]) inputInspector_.getPrimitiveJavaObject(parameters[0]); |
| if (serializedSketch == null) { return; } |
| state.update(HllSketch.wrap(Memory.wrap(serializedSketch))); |
| } |
| |
| private void initializeState(final UnionState 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); |
| } |
| |
| } |
| |
| } |