docs/topics/impala_hbase_caching.xml

<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
<concept id="hbase_caching">

  <title>HBASE_CACHING Query Option</title>
  <titlealts audience="PDF"><navtitle>HBASE_CACHING</navtitle></titlealts>
  <prolog>
    <metadata>
      <data name="Category" value="Impala"/>
      <data name="Category" value="HBase"/>
      <data name="Category" value="Impala Query Options"/>
      <data name="Category" value="Developers"/>
      <data name="Category" value="Data Analysts"/>
    </metadata>
  </prolog>

  <conbody>

    <p>
      <indexterm audience="hidden">HBASE_CACHING query option</indexterm>
      Setting this option is equivalent to calling the
        <codeph>setCaching</codeph> method of the class <xref
        href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/Scan.html"
        scope="external" format="html"
        >org.apache.hadoop.hbase.client.Scan</xref>, in an HBase Java
      application. Helps to control the memory pressure on the HBase
      RegionServer, in conjunction with the <codeph>HBASE_CACHE_BLOCKS</codeph>
      query option. </p>

    <p>
      <b>Type:</b> <codeph>BOOLEAN</codeph>
    </p>

    <p>
      <b>Default:</b> 0
    </p>

    <p conref="../shared/impala_common.xml#common/related_info"/>
    <p>
      <xref href="impala_hbase.xml#impala_hbase"/>,
      <xref href="impala_hbase_cache_blocks.xml#hbase_cache_blocks"/>
    </p>

  </conbody>
</concept>