github-actions[bot] commented on code in PR #63143: URL: https://github.com/apache/doris/pull/63143#discussion_r3253184322
########## be/src/exprs/aggregate/aggregate_function_datasketches_hll_union_agg.h: ########## @@ -0,0 +1,177 @@ +// 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 <stddef.h> + +#include <DataSketches/hll.hpp> +#include <boost/iterator/iterator_facade.hpp> +#include <memory> +#include <type_traits> +#include <vector> + +#include "common/compiler_util.h" // IWYU pragma: keep +#include "core/assert_cast.h" +#include "core/column/column.h" +#include "core/column/column_vector.h" +#include "core/data_type/data_type_number.h" +#include "core/data_type/define_primitive_type.h" +#include "core/field.h" +#include "core/string_ref.h" +#include "core/types.h" +#include "core/uint128.h" +#include "exec/common/hash_table/hash.h" +#include "exec/common/hash_table/phmap_fwd_decl.h" +#include "exprs/aggregate/aggregate_function.h" +#include "util/var_int.h" +template <typename T> +struct HashCRC32; +namespace doris { +class Arena; +class BufferReadable; +class BufferWritable; +template <PrimitiveType T> +class ColumnDecimal; +/// datasketches_hll_union_agg +template <PrimitiveType T> +struct AggregateFunctionHllSketchData { + /** We set the default LgK to 12, + * as this value is used as a performance baseline in the relevant documentation. + * (https://datasketches.apache.org/docs/HLL/HllPerformance.html) + */ + static const uint8_t DEFAULT_LOG_K = 12; + std::unique_ptr<datasketches::hll_union> hll_union_data; + static String get_name() { return "datasketches_hll_union_agg"; } + void merge(const datasketches::hll_sketch& sketch_data) { + if (hll_union_data == nullptr) { + hll_union_data = + std::make_unique<datasketches::hll_union>(sketch_data.get_lg_config_k()); + } + try { + hll_union_data->update(sketch_data); + } catch (...) { + throw Exception(ErrorCode::INTERNAL_ERROR, + "Internal error happened when update HLL sketch."); + } + } + void reset() { + if (hll_union_data != nullptr) { + hll_union_data->reset(); + } + hll_union_data = nullptr; + } + void write_sketch(BufferWritable& buf, const datasketches::hll_sketch& sk) const { + auto serialized_bytes = sk.serialize_compact(); + StringRef d(serialized_bytes.data(), serialized_bytes.size()); + buf.write_binary(d); + } + void write(BufferWritable& buf) const { + if (hll_union_data == nullptr) { + /** Using DEFAULT_LOG_K(12) here is surely sufficient, + * because in this case the union that actually needs to be serialized should contain no data. + */ + datasketches::hll_union u(DEFAULT_LOG_K); + write_sketch(buf, u.get_result()); + return; + } + try { + auto cache = hll_union_data->get_result(); + write_sketch(buf, cache); + } catch (...) { + throw Exception(ErrorCode::INTERNAL_ERROR, + "Internal error happened when serialize HLL sketch."); + } + } + void read(BufferReadable& buf) { + StringRef d; + buf.read_binary(d); + try { + auto cache = datasketches::hll_sketch::deserialize(d.data, d.size); + merge(cache); + } catch (...) { + throw Exception(ErrorCode::CORRUPTION, "HLL sketch data corrupted when read."); + } + } + int64_t get_result() const { + if (hll_union_data != nullptr) { + try { + return static_cast<int64_t>(hll_union_data->get_estimate()); + } catch (...) { + throw Exception(ErrorCode::INTERNAL_ERROR, + "Internal error happened when get HLL sketch estimate."); + } + } + return 0; + } +}; +namespace detail { +/** The structure for the delegation work to add one element to the `datasketches_hll_union_agg` aggregate functions. + * Used for partial specialization to add strings. + */ +template <PrimitiveType T, typename Data> +struct OneAdder { + static void ALWAYS_INLINE add(Data& data, const IColumn& column, size_t row_num) { + if constexpr (is_string_type(T) || is_varbinary(T)) { + StringRef value = column.get_data_at(row_num); + if (value.empty()) { + return; + } + try { + datasketches::hll_sketch sketch_data = + datasketches::hll_sketch::deserialize(value.begin(), value.size); + data.merge(sketch_data); + } catch (...) { + throw Exception(ErrorCode::CORRUPTION, "HLL sketch data corrupted when add."); + } + } + } +}; +} // namespace detail +/// Calculates the number of different values approximately using hll sketch. +template <PrimitiveType T, typename Data> +class AggregateFunctionDataSketchesHllUnionAgg final + : public IAggregateFunctionDataHelper<Data, + AggregateFunctionDataSketchesHllUnionAgg<T, Data>>, + VarargsExpression, + NotNullableAggregateFunction { +public: + AggregateFunctionDataSketchesHllUnionAgg(const DataTypes& argument_types_) + : IAggregateFunctionDataHelper<Data, AggregateFunctionDataSketchesHllUnionAgg<T, Data>>( + argument_types_) {} + String get_name() const override { return Data::get_name(); } + DataTypePtr get_return_type() const override { return std::make_shared<DataTypeInt64>(); } + void reset(AggregateDataPtr __restrict place) const override { this->data(place).reset(); } + void add(AggregateDataPtr __restrict place, const IColumn** columns, ssize_t row_num, + Arena&) const override { + detail::OneAdder<T, Data>::add(this->data(place), *columns[0], row_num); + } + void merge(AggregateDataPtr __restrict place, ConstAggregateDataPtr rhs, + Arena&) const override { + this->data(place).merge(this->data(rhs).hll_union_data->get_result(datasketches::HLL_8)); Review Comment: This merge path assumes the rhs state has already seen a non-empty sketch, but `add()` leaves `hll_union_data` null for NULL inputs (via the default nullable handling) and for empty strings (line 130). A grouped/partial aggregate state can therefore exist for a key whose rows are all NULL/empty, and merging that state dereferences `rhs.hll_union_data` here. Please handle the empty rhs state the same way `serialize()`/`insert_result_into()` do, e.g. skip merging when rhs has no union data or merge an explicit empty sketch, and add a test that merges an empty state. ########## fe/fe-core/src/main/java/org/apache/doris/catalog/ColumnToThrift.java: ########## @@ -112,6 +112,8 @@ public static TAggregationType toThrift(AggregateType aggregateType) { return TAggregationType.NONE; case HLL_UNION: return TAggregationType.HLL_UNION; + case DATASKETCHES_HLL_UNION_AGG: + return TAggregationType.DATASKETCHES_HLL_UNION; Review Comment: This exposes `DATASKETCHES_HLL_UNION_AGG` as a table aggregation type, but the BE tablet schema/storage side is not updated to understand `DATASKETCHES_HLL_UNION`. `tablet_meta.cpp` converts this enum to the string `DATASKETCHES_HLL_UNION`, and `TabletColumn::get_aggregation_type_by_string()` currently treats any non-empty unknown string as `OLAP_FIELD_AGGREGATION_GENERIC`, which creates an `AggStateField` rather than a string/datasketches union aggregation field. A table or rollup using this aggregate type will therefore be created with the wrong BE aggregation implementation. Please either complete the BE storage aggregation support and add an aggregate-key/pre-agg regression test, or do not expose this as an `AggregateType`/pre-agg mode yet. -- 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: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
