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       <h1>Format-specific scan options</h1>
       <small class="dont-index">Source: <a href="https://github.com/apache/arrow/blob/main/r/R/dataset-format.R" class="external-link"><code>R/dataset-format.R</code></a></small>
       <div class="d-none name"><code>FragmentScanOptions.Rd</code></div>
     </div>

     <div class="ref-description section level2">
     <p>A <code>FragmentScanOptions</code> holds options specific to a <code>FileFormat</code> and a scan
 operation.</p>
     </div>


     <div class="section level2">
     <h2 id="factory">Factory<a class="anchor" aria-label="anchor" href="#factory"></a></h2>


 <p><code>FragmentScanOptions$create()</code> takes the following arguments:</p><ul><li><p><code>format</code>: A string identifier of the file format. Currently supported values:</p><ul><li><p>"parquet"</p></li>
 <li><p>"csv"/"text", aliases for the same format.</p></li>
 </ul></li>
 <li><p><code>...</code>: Additional format-specific options</p>
 <p><code>format = "parquet"</code>:</p><ul><li><p><code>use_buffered_stream</code>: 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.</p></li>
 <li><p><code>buffer_size</code>: Size of buffered stream, if enabled. Default is 8KB.</p></li>
 <li><p><code>pre_buffer</code>: Pre-buffer the raw Parquet data. This can improve performance
 on high-latency filesystems. Disabled by default.</p></li>
 <li><p><code>thrift_string_size_limit</code>: 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.</p></li>
 <li><p><code>thrift_container_size_limit</code>: Maximum size of thrift containers.  May need to be
 increased in order to read files with especially large
 headers. Default value 1000000.
 <code>format = "text"</code>: see <a href="CsvReadOptions.html">CsvConvertOptions</a>. Note that options can only be
 specified with the Arrow C++ library naming. Also, "block_size" from
 <a href="CsvReadOptions.html">CsvReadOptions</a> may be given.</p></li>
 </ul></li>
 </ul><p>It returns the appropriate subclass of <code>FragmentScanOptions</code>
 (e.g. <code>CsvFragmentScanOptions</code>).</p>
     </div>

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	<h1>Format-specific scan options</h1>
	<small class="dont-index">Source: <a href="https://github.com/apache/arrow/blob/main/r/R/dataset-format.R" class="external-link"><code>R/dataset-format.R</code></a></small>
	<div class="d-none name"><code>FragmentScanOptions.Rd</code></div>
	</div>

	<div class="ref-description section level2">
	<p>A <code>FragmentScanOptions</code> holds options specific to a <code>FileFormat</code> and a scan
	operation.</p>
	</div>


	<div class="section level2">
	<h2 id="factory">Factory<a class="anchor" aria-label="anchor" href="#factory"></a></h2>


	<p><code>FragmentScanOptions$create()</code> takes the following arguments:</p><ul><li><p><code>format</code>: A string identifier of the file format. Currently supported values:</p><ul><li><p>"parquet"</p></li>
	<li><p>"csv"/"text", aliases for the same format.</p></li>
	</ul></li>
	<li><p><code>...</code>: Additional format-specific options</p>
	<p><code>format = "parquet"</code>:</p><ul><li><p><code>use_buffered_stream</code>: 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.</p></li>
	<li><p><code>buffer_size</code>: Size of buffered stream, if enabled. Default is 8KB.</p></li>
	<li><p><code>pre_buffer</code>: Pre-buffer the raw Parquet data. This can improve performance
	on high-latency filesystems. Disabled by default.</p></li>
	<li><p><code>thrift_string_size_limit</code>: 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.</p></li>
	<li><p><code>thrift_container_size_limit</code>: Maximum size of thrift containers. May need to be
	increased in order to read files with especially large
	headers. Default value 1000000.
	<code>format = "text"</code>: see <a href="CsvReadOptions.html">CsvConvertOptions</a>. Note that options can only be
	specified with the Arrow C++ library naming. Also, "block_size" from
	<a href="CsvReadOptions.html">CsvReadOptions</a> may be given.</p></li>
	</ul></li>
	</ul><p>It returns the appropriate subclass of <code>FragmentScanOptions</code>
	(e.g. <code>CsvFragmentScanOptions</code>).</p>
	</div>

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