![]() ![]() Omitting fields and allows for new row groups to be created automatically This type-safe approach also ensures that rows are written without Standard C++ output operators, similar to reading with the StreamReaderĬlass. The StreamWriter allows for Parquet files to be written using Build ()) std :: shared_ptr rb_reader ARROW_RETURN_NOT_OK ( arrow_reader -> GetRecordBatchReader ( & rb_reader )) for ( arrow :: Result > maybe_batch : * rb_reader ) // Write file footer and close ARROW_RETURN_NOT_OK ( writer -> Close ()) StreamWriter # ![]() properties ( arrow_reader_props ) std :: unique_ptr arrow_reader ARROW_ASSIGN_OR_RAISE ( arrow_reader, reader_builder. OpenFile ( path_to_file, /*memory_map=*/ false, reader_properties )) reader_builder. set_batch_size ( 128 * 1024 ) // default 64 * 1024 parquet :: arrow :: FileReaderBuilder reader_builder ARROW_RETURN_NOT_OK ( reader_builder. enable_buffered_stream () // Configure Arrow-specific Parquet reader settings auto arrow_reader_props = parquet :: ArrowReaderProperties () arrow_reader_props. ![]() set_buffer_size ( 4096 * 4 ) reader_properties. #include "arrow/io/api.h" // #include "arrow/parquet/arrow/reader.h" arrow :: MemoryPool * pool = arrow :: default_memory_pool () // Configure general Parquet reader settings auto reader_properties = parquet :: ReaderProperties ( pool ) reader_properties. To construct, it requires a ::arrow::io::RandomAccessFile instance To read Parquet data into Arrow structures, use arrow::FileReader. Please note that the performance of the StreamReader will notīe as good due to the type checking and the fact that column valuesĪre processed one at a time. It is of course also useful whenĭata must be streamed as files are read and written incrementally. Is offered for ease of use and type-safety. Stream approach to read fields column by column and row by row. The StreamReader class allows for data to be read using a C++ input The arrow::FileReader class reads data into Arrow Tables and Record The ParquetĬ++ implementation is part of the Apache Arrow project and benefitsįrom tight integration with the Arrow C++ classes and facilities. Is a space-efficient columnar storage format for complex data. ![]()
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