A FragmentScanOptions holds options specific to a FileFormat and a scan
operation.
Factory
FragmentScanOptions$create() takes the following arguments:
- format: A string identifier of the file format. Currently supported values:- "parquet" 
- "csv"/"text", aliases for the same format. 
 
- ...: Additional format-specific options- format = "parquet":- use_buffered_stream: Read files through buffered input streams rather than loading entire row groups at once. This may be enabled to reduce memory overhead. Disabled by default.
- buffer_size: Size of buffered stream, if enabled. Default is 8KB.
- pre_buffer: Pre-buffer the raw Parquet data. This can improve performance on high-latency filesystems. Disabled by default.
- thrift_string_size_limit: Maximum string size allocated for decoding thrift strings. May need to be increased in order to read files with especially large headers. Default value 100000000.
- thrift_container_size_limit: Maximum size of thrift containers. May need to be increased in order to read files with especially large headers. Default value 1000000.- format = "text": see CsvConvertOptions. Note that options can only be specified with the Arrow C++ library naming. Also, "block_size" from CsvReadOptions may be given.
 
It returns the appropriate subclass of FragmentScanOptions
(e.g. CsvFragmentScanOptions).