superdiaodiao commented on code in PR #39546: URL: https://github.com/apache/doris/pull/39546#discussion_r1734319148
########## be/src/vec/aggregate_functions/aggregate_function_linear_histogram.h: ########## @@ -0,0 +1,241 @@ +// 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. + +#pragma once + +#include <rapidjson/document.h> +#include <rapidjson/prettywriter.h> +#include <rapidjson/stringbuffer.h> + +#include <map> + +#include "vec/aggregate_functions/aggregate_function.h" +#include "vec/aggregate_functions/aggregate_function_simple_factory.h" +#include "vec/core/types.h" +#include "vec/data_types/data_type_decimal.h" +#include "vec/io/io_helper.h" + +// TODO: optimize count=0 +// TODO: support datetime +// TODO: support foreach + +namespace doris::vectorized { + +template <typename T> +struct AggregateFunctionLinearHistogramData { + // bucket key limits + const static int32_t MIN_BUCKET_KEY = std::numeric_limits<int32_t>::min(); + const static int32_t MAX_BUCKET_KEY = std::numeric_limits<int32_t>::max(); + +private: + // influxdb use double + double interval = 0; + double offset; + double lower; // not used yet + double upper; // not used yet + std::map<int32_t, size_t> buckets; + +public: + // reset + void reset() { + offset = 0; + interval = 0; + buckets.clear(); + } + + void set_parameters(double input_interval, double input_offset) { + interval = input_interval; + offset = input_offset; + } + + // add + void add(const T& value, UInt32 scale) { + double val = 0; + if constexpr (IsDecimalNumber<T>) { + using NativeType = typename T::NativeType; + val = static_cast<double>(value.value) / decimal_scale_multiplier<NativeType>(scale); + } else { + val = static_cast<double>(value); + } + double key = std::floor((val - offset) / interval); + if (key <= MIN_BUCKET_KEY || key >= MAX_BUCKET_KEY) { + throw doris::Exception(ErrorCode::INVALID_ARGUMENT, "{} exceeds the bucket range limit", + value); + } + buckets[static_cast<int32_t>(key)]++; + } + + // merge + void merge(const AggregateFunctionLinearHistogramData& rhs) { + if (rhs.interval == 0) { + return; + } + + interval = rhs.interval; + offset = rhs.offset; + + for (const auto& [key, count] : rhs.buckets) { + buckets[key] += count; + } + } + + // write + void write(BufferWritable& buf) const { + write_binary(offset, buf); + write_binary(interval, buf); + write_binary(lower, buf); + write_binary(upper, buf); + write_binary(buckets.size(), buf); + for (const auto& [key, count] : buckets) { + write_binary(key, buf); + write_binary(count, buf); + } + } + + // read + void read(BufferReadable& buf) { + read_binary(offset, buf); + read_binary(interval, buf); + read_binary(lower, buf); + read_binary(upper, buf); + size_t size; + read_binary(size, buf); + for (size_t i = 0; i < size; i++) { + int32_t key; + size_t count; + read_binary(key, buf); + read_binary(count, buf); + buckets[key] = count; + } + } + + // insert_result_into + void insert_result_into(IColumn& to) const { + rapidjson::Document doc; + doc.SetObject(); + rapidjson::Document::AllocatorType& allocator = doc.GetAllocator(); + + unsigned num_buckets = + buckets.empty() ? 0 : buckets.rbegin()->first - buckets.begin()->first + 1; + doc.AddMember("num_buckets", num_buckets, allocator); + + rapidjson::Value bucket_arr(rapidjson::kArrayType); + bucket_arr.Reserve(num_buckets, allocator); + + int32_t idx = buckets.begin()->first; + double left = buckets.begin()->first * interval + offset; + size_t count = 0; + size_t acc_count = 0; + + for (const auto& [key, count_] : buckets) { + for (; idx <= key; ++idx) { + rapidjson::Value bucket_json(rapidjson::kObjectType); + bucket_json.AddMember("lower", left, allocator); + left += interval; + bucket_json.AddMember("upper", left, allocator); + count = (idx == key) ? count_ : 0; + bucket_json.AddMember("count", count, allocator); + acc_count += count; + bucket_json.AddMember("acc_count", acc_count, allocator); + + bucket_arr.PushBack(bucket_json, allocator); + } + } + + doc.AddMember("buckets", bucket_arr, allocator); + + rapidjson::StringBuffer buffer; + rapidjson::Writer<rapidjson::StringBuffer> writer(buffer); + doc.Accept(writer); + + auto& column = assert_cast<ColumnString&>(to); + column.insert_data(buffer.GetString(), buffer.GetSize()); + } +}; + +template <typename T, typename Data, bool has_offset> +class AggregateFunctionLinearHistogram final + : public IAggregateFunctionDataHelper< + Data, AggregateFunctionLinearHistogram<T, Data, has_offset>> { +public: + using ColVecType = ColumnVectorOrDecimal<T>; + + AggregateFunctionLinearHistogram(const DataTypes& argument_types_) + : IAggregateFunctionDataHelper<Data, + AggregateFunctionLinearHistogram<T, Data, has_offset>>( + argument_types_), + scale(get_decimal_scale(*argument_types_[0])) {} + + std::string get_name() const override { return "linear_histogram"; } + + DataTypePtr get_return_type() const override { return std::make_shared<DataTypeString>(); } + + void add(AggregateDataPtr __restrict place, const IColumn** columns, ssize_t row_num, + Arena* arena) const override { + double interval = + assert_cast<const ColumnFloat64&, TypeCheckOnRelease::DISABLE>(*columns[1]) + .get_data()[row_num]; + if (interval <= 0) { + throw doris::Exception(ErrorCode::INVALID_ARGUMENT, "Invalid interval {}, row_num {}", + interval, row_num); Review Comment: Add more info for `interval` would be better, i.e., it should be larger than 0. On the other hand, just asking, why not make this situation return null rather than throw exception? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: commits-unsubscr...@doris.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@doris.apache.org For additional commands, e-mail: commits-h...@doris.apache.org
