wgtmac commented on code in PR #112: URL: https://github.com/apache/iceberg-cpp/pull/112#discussion_r2110719450
########## src/iceberg/table_scan.h: ########## @@ -0,0 +1,117 @@ +/* + * 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/expression/expression.h" +#include "iceberg/file_io.h" Review Comment: ```suggestion ``` It seems that we don't need them? ########## src/iceberg/table_scan.h: ########## @@ -0,0 +1,117 @@ +/* + * 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/expression/expression.h" +#include "iceberg/file_io.h" +#include "iceberg/manifest_entry.h" +#include "iceberg/type_fwd.h" + +namespace iceberg { + +/// \brief Builder class for creating TableScan instances. +class ICEBERG_EXPORT TableScanBuilder { + public: + /// \brief Constructs a TableScanBuilder for the given table. + /// \param table Reference to the table to scan. + explicit TableScanBuilder(const Table& table); + + /// \brief Sets the snapshot ID to scan. + /// \param snapshot_id The ID of the snapshot. + /// \return Reference to the builder. + TableScanBuilder& WithSnapshotId(int64_t snapshot_id); + + /// \brief Selects columns to include in the scan. + /// \param column_names A list of column names. + /// \return Reference to the builder. + TableScanBuilder& WithColumnNames(const std::vector<std::string>& column_names); + + /// \brief Applies a filter expression to the scan. + /// \param filter Filter expression to use. + /// \return Reference to the builder. + TableScanBuilder& WithFilter(const std::shared_ptr<Expression>& filter); + + /// \brief Builds and returns a TableScan instance. + /// \return A Result containing the TableScan or an error. + Result<std::unique_ptr<TableScan>> Build(); + + private: + const Table& table_; + std::vector<std::string> column_names_; + std::optional<int64_t> snapshot_id_; + std::shared_ptr<Expression> filter_; +}; + +/// \brief Represents a configured scan operation on a table. +class ICEBERG_EXPORT TableScan { + public: + /// \brief Scan context holding snapshot and scan-specific metadata. + struct ScanContext { + std::shared_ptr<Snapshot> snapshot_; ///< Snapshot to scan. + std::shared_ptr<Schema> schema_; ///< Projected schema. + std::vector<int32_t> field_ids_; ///< Field IDs of selected columns. + std::shared_ptr<Expression> filter_; ///< Filter expression to apply. + }; + + /// \brief Constructs a TableScan with the given context and file I/O. + /// \param context Scan context including snapshot, schema, and filter. + /// \param file_io File I/O instance for reading manifests and data files. + TableScan(std::unique_ptr<ScanContext> context, std::shared_ptr<FileIO> file_io); + + /// \brief Plans the scan tasks by resolving manifests and data files. + /// + /// Returns a list of file scan tasks if successful. + /// \return A Result containing scan tasks or an error. + Result<std::vector<std::shared_ptr<FileScanTask>>> PlanFiles() const; + + private: + /// \brief Creates a reader for the manifest list. + /// \param file_path Path to the manifest list file. + /// \return A Result containing the reader or an error. + Result<std::unique_ptr<ManifestListReader>> CreateManifestListReader( + const std::string& file_path) const; + + /// \brief Creates a reader for a manifest file. + /// \param file_path Path to the manifest file. + /// \return A Result containing the reader or an error. + Result<std::unique_ptr<ManifestReader>> CreateManifestReader( + const std::string& file_path) const; + + std::unique_ptr<ScanContext> context_; + std::shared_ptr<FileIO> file_io_; +}; + +/// \brief Represents a task to scan a portion of a data file. +struct ICEBERG_EXPORT FileScanTask { + std::string file_path; ///< Path to the data file. + uint64_t start; ///< Start byte offset. + uint64_t length; ///< Length in bytes to scan. + std::optional<uint64_t> record_count; ///< Optional number of records. + DataFile::Content file_content; ///< Type of file content. + FileFormatType file_format; ///< Format of the data file. + std::shared_ptr<Schema> schema; ///< Projected schema. + std::vector<int32_t> field_ids; ///< Field IDs to project. Review Comment: Why do we need this? Isn't it included in the `schema` above? ########## src/iceberg/table_scan.h: ########## @@ -0,0 +1,117 @@ +/* + * 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/expression/expression.h" +#include "iceberg/file_io.h" +#include "iceberg/manifest_entry.h" +#include "iceberg/type_fwd.h" + +namespace iceberg { + +/// \brief Builder class for creating TableScan instances. +class ICEBERG_EXPORT TableScanBuilder { + public: + /// \brief Constructs a TableScanBuilder for the given table. + /// \param table Reference to the table to scan. + explicit TableScanBuilder(const Table& table); + + /// \brief Sets the snapshot ID to scan. + /// \param snapshot_id The ID of the snapshot. + /// \return Reference to the builder. + TableScanBuilder& WithSnapshotId(int64_t snapshot_id); + + /// \brief Selects columns to include in the scan. + /// \param column_names A list of column names. + /// \return Reference to the builder. + TableScanBuilder& WithColumnNames(const std::vector<std::string>& column_names); + + /// \brief Applies a filter expression to the scan. + /// \param filter Filter expression to use. + /// \return Reference to the builder. + TableScanBuilder& WithFilter(const std::shared_ptr<Expression>& filter); + + /// \brief Builds and returns a TableScan instance. + /// \return A Result containing the TableScan or an error. + Result<std::unique_ptr<TableScan>> Build(); + + private: + const Table& table_; + std::vector<std::string> column_names_; + std::optional<int64_t> snapshot_id_; + std::shared_ptr<Expression> filter_; +}; + +/// \brief Represents a configured scan operation on a table. +class ICEBERG_EXPORT TableScan { + public: + /// \brief Scan context holding snapshot and scan-specific metadata. + struct ScanContext { + std::shared_ptr<Snapshot> snapshot_; ///< Snapshot to scan. + std::shared_ptr<Schema> schema_; ///< Projected schema. + std::vector<int32_t> field_ids_; ///< Field IDs of selected columns. + std::shared_ptr<Expression> filter_; ///< Filter expression to apply. + }; + + /// \brief Constructs a TableScan with the given context and file I/O. + /// \param context Scan context including snapshot, schema, and filter. + /// \param file_io File I/O instance for reading manifests and data files. + TableScan(std::unique_ptr<ScanContext> context, std::shared_ptr<FileIO> file_io); + + /// \brief Plans the scan tasks by resolving manifests and data files. + /// + /// Returns a list of file scan tasks if successful. + /// \return A Result containing scan tasks or an error. + Result<std::vector<std::shared_ptr<FileScanTask>>> PlanFiles() const; + + private: + /// \brief Creates a reader for the manifest list. + /// \param file_path Path to the manifest list file. + /// \return A Result containing the reader or an error. + Result<std::unique_ptr<ManifestListReader>> CreateManifestListReader( + const std::string& file_path) const; + + /// \brief Creates a reader for a manifest file. + /// \param file_path Path to the manifest file. + /// \return A Result containing the reader or an error. + Result<std::unique_ptr<ManifestReader>> CreateManifestReader( + const std::string& file_path) const; + + std::unique_ptr<ScanContext> context_; + std::shared_ptr<FileIO> file_io_; +}; + +/// \brief Represents a task to scan a portion of a data file. +struct ICEBERG_EXPORT FileScanTask { Review Comment: Before defining `FileScanTask`, should we abstract it a little bit? I haven't looked at other implementations yet. From the java impl, there's a hierarchy of `ScanTask` and `FileScanTask` is a combination of `ContentScanTask` and `PartitionScanTask`. I'm not sure if we want to take the complexity to support the java `SplittableScanTask`, `MergableScanTask`, and `ScanTaskGroup`. We can revisit these later. ########## src/iceberg/type_fwd.h: ########## @@ -91,6 +91,10 @@ class LocationProvider; class SortField; class SortOrder; class Table; +class TableScan; Review Comment: What about putting all scan related structures into a separate section for better readability? ########## src/iceberg/table_scan.h: ########## @@ -0,0 +1,117 @@ +/* + * 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/expression/expression.h" +#include "iceberg/file_io.h" +#include "iceberg/manifest_entry.h" Review Comment: If the only reason to include `manifest_entry.h` is to use `enum DataFile::Content`, what about refactoring it into `enum DataFileContent` and moving it to `type_fwd.h`? ########## src/iceberg/table_scan.h: ########## @@ -0,0 +1,117 @@ +/* + * 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/expression/expression.h" +#include "iceberg/file_io.h" +#include "iceberg/manifest_entry.h" +#include "iceberg/type_fwd.h" + +namespace iceberg { + +/// \brief Builder class for creating TableScan instances. +class ICEBERG_EXPORT TableScanBuilder { Review Comment: Do we need an abstraction for common parts of other scan builders? We may need more scan types for incremental, append-only, changelog, etc. If there's not much to abstract, I'm fine to keep it as is for now and refactor them later. ########## src/iceberg/table_scan.h: ########## @@ -0,0 +1,117 @@ +/* + * 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/expression/expression.h" +#include "iceberg/file_io.h" +#include "iceberg/manifest_entry.h" +#include "iceberg/type_fwd.h" + +namespace iceberg { + +/// \brief Builder class for creating TableScan instances. +class ICEBERG_EXPORT TableScanBuilder { + public: + /// \brief Constructs a TableScanBuilder for the given table. + /// \param table Reference to the table to scan. + explicit TableScanBuilder(const Table& table); + + /// \brief Sets the snapshot ID to scan. + /// \param snapshot_id The ID of the snapshot. + /// \return Reference to the builder. + TableScanBuilder& WithSnapshotId(int64_t snapshot_id); + + /// \brief Selects columns to include in the scan. Review Comment: Add a comment to explain what will happen if we don't set any column name? -- 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
