eldenmoon commented on code in PR #66204: URL: https://github.com/apache/doris/pull/66204#discussion_r3718514894
########## be/src/storage/segment/variant/v2/variant_path_builder.h: ########## @@ -0,0 +1,122 @@ +// 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 <cstddef> +#include <cstdint> +#include <memory> +#include <span> + +#include "common/status.h" +#include "core/column/column.h" +#include "core/column/column_string.h" +#include "core/custom_allocator.h" +#include "core/data_type/data_type.h" +#include "core/value/variant/variant_value.h" +#include "util/json/path_in_data.h" + +namespace doris::segment_v2 { + +struct VariantPathColumn { + PathInData path; + DataTypePtr type; + ColumnPtr column; + uint32_t non_null_rows = 0; +}; + +// An incrementally promotable builder for one flattened Variant path. Present leaves are stored +// compactly beside their ordered logical row ids; missing rows are materialized only for paths +// selected as physical subcolumns. The builder owns every byte after append returns. +class VariantPathBuilder final { +public: + explicit VariantPathBuilder(PathInData path, size_t prefix_rows = 0); + ~VariantPathBuilder(); + + VariantPathBuilder(VariantPathBuilder&&) noexcept; + VariantPathBuilder& operator=(VariantPathBuilder&&) noexcept; + VariantPathBuilder(const VariantPathBuilder&) = delete; + VariantPathBuilder& operator=(const VariantPathBuilder&) = delete; + + Status append(VariantRef value, size_t row); + Status complete_rows(size_t rows); + Status convert_to(const DataTypePtr& storage_type); + + const PathInData& path() const; + const DataTypePtr& type() const; + std::span<const uint32_t> rowids() const; + uint32_t non_null_rows() const; +#ifdef BE_TEST + size_t rows() const; + size_t promotion_count() const; + bool is_null_at(size_t row) const; +#endif + size_t byte_size() const; + + Status materialize(ColumnPtr* result) const; + Status write_sparse_cell(size_t value_index, ColumnString::Chars* chars) const; + +private: + struct Impl; + std::unique_ptr<Impl> _impl; +}; + +struct VariantPathSelectionCandidate { + const VariantPathBuilder* builder = nullptr; + bool is_typed_path = false; +}; + +struct VariantPathSelection { + DorisVector<size_t> materialized; + DorisVector<size_t> sparse; +}; + +// Typed paths are fixed unless typed_paths_to_sparse is enabled. Dynamic paths are ordered by the +// authoritative non-null-count/depth/path rule before the materialization budget is applied. +VariantPathSelection select_variant_paths(std::span<const VariantPathSelectionCandidate> candidates, + size_t max_dynamic_materialized_paths, + bool typed_paths_to_sparse); + +// Compiles metadata dictionary ids and parent+field transitions once. Callers resolve row data +// through stable numeric ids; only the first occurrence of a unique metadata/path pair constructs +// or hashes a path string. +class VariantMetadataPathPlan final { Review Comment: 这个不必要引入， 直接用简单的Cache -- 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]
