wgtmac commented on code in PR #112: URL: https://github.com/apache/iceberg-cpp/pull/112#discussion_r2177408751
########## src/iceberg/table_scan.h: ########## @@ -0,0 +1,204 @@ +/* + * 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 <string> +#include <vector> + +#include "iceberg/manifest_entry.h" +#include "iceberg/type_fwd.h" + +namespace iceberg { + +class ICEBERG_EXPORT ScanTask { + public: + virtual ~ScanTask() = default; + + /// \brief The number of bytes that should be read by this scan task. + virtual int64_t size_bytes() const = 0; + + /// \brief The number of files that should be read by this scan task. + virtual int32_t files_count() const = 0; + + /// \brief The number of rows that should be read by this scan task. + virtual int64_t estimated_row_count() const = 0; +}; + +/// \brief Represents a task to scan a portion of a data file. +class ICEBERG_EXPORT FileScanTask : public ScanTask { + public: + FileScanTask(std::shared_ptr<DataFile> file, + std::vector<std::shared_ptr<DataFile>> delete_files, int64_t start, + int64_t length, std::shared_ptr<Expression> residual); + + /// \brief The data file that should be read by this scan task. + const std::shared_ptr<DataFile>& data_file() const; + + /// \brief The delete files that should be read by this scan task. + const std::vector<std::shared_ptr<DataFile>>& delete_files() const; + + /// \brief The byte offset in the data file where the scan should start. + int64_t start() const; + + /// \brief The length in bytes to scan from the start offset. + int64_t length() const; + + /// \brief The residual expression to apply after scanning the data file. + const std::shared_ptr<Expression>& residual() const; + + int64_t size_bytes() const override; + int32_t files_count() const override; + int64_t estimated_row_count() const override; + + private: + std::shared_ptr<DataFile> data_file_; ///< Data file metadata. + std::vector<std::shared_ptr<DataFile>> delete_files_; ///< Delete files metadata. + + int64_t start_; ///< Start byte offset. + int64_t length_; ///< Length in bytes to scan. + + std::shared_ptr<Expression> residual_; ///< Residual expression to apply. +}; + +/// \brief Scan context holding snapshot and scan-specific metadata. +struct TableScanContext { + std::shared_ptr<TableMetadata> table_metadata; ///< Table metadata. + std::shared_ptr<Snapshot> snapshot; ///< Snapshot to scan. + std::shared_ptr<Schema> projected_schema; ///< Projected schema. + std::shared_ptr<Expression> filter; ///< Filter expression to apply. + bool case_sensitive = false; ///< Whether the scan is case-sensitive. + std::unordered_map<std::string, std::string> + options; ///< Additional options for the scan. + std::optional<int64_t> limit; ///< Optional limit on the number of rows to scan. +}; + +/// \brief Builder class for creating TableScan instances. +class ICEBERG_EXPORT TableScanBuilder { + public: + /// \brief Constructs a TableScanBuilder for the given table. + /// \param table The table to scan. + /// \param table_metadata The metadata of the table to scan. + explicit TableScanBuilder(const Table& table, Review Comment: `Table` is just a wrapper around `TableMetadata`. I think we could either (1) expose `TableMetadata` via `Table` (and thus remove `table_metadata` from ctor), or (2) remove `table` and add `file_io` to ctor. I think passing a reference of table may cause lifetime issue. I prefer (2) here. WDYT? -- 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: issues-unsubscr...@iceberg.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For additional commands, e-mail: issues-h...@iceberg.apache.org
