docs/topics/impala_live_progress.xml

<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
<concept rev="2.3.0" id="live_progress">

  <title>LIVE_PROGRESS Query Option (<keyword keyref="impala23"/> or higher only)</title>
  <titlealts audience="PDF"><navtitle>LIVE_PROGRESS</navtitle></titlealts>
  <prolog>
    <metadata>
      <data name="Category" value="Impala"/>
      <data name="Category" value="Impala Query Options"/>
      <data name="Category" value="Querying"/>
      <data name="Category" value="Performance"/>
      <data name="Category" value="Reports"/>
      <data name="Category" value="impala-shell"/>
      <data name="Category" value="Developers"/>
      <data name="Category" value="Data Analysts"/>
    </metadata>
  </prolog>

  <conbody>

    <p> In Impala 3.4.0 and higher when you start the Impala shell in interactive mode, the
        <codeph>LIVE_PROGRESS</codeph> query option is set to <codeph>TRUE</codeph> by default. When
      you run a query, the live progress bar appears in the output of a query. The bar shows roughly
      the percentage of completed processing. When the query finishes, the live progress bar
      disappears from the console output. </p>
    <p>Starting in <keyword keyref="impala31"/>, the summary output also
      includes the queuing status consisting of whether the query was queued and
      what was the latest queuing reason.</p>
    <p><b>Type:</b>
      <codeph>Boolean</codeph></p>
    <p><b>Default:</b>
      <codeph>TRUE (0)</codeph></p>

    <p conref="../shared/impala_common.xml#common/command_line_blurb"/>
    <p> You can turn off <codeph>LIVE_PROGRESS</codeph> within the shell 
      using the <codeph>SET</codeph> command. You can also turn off
      LIVE_PROGRESS by starting the shell with the <codeph>--disable_live_progress</codeph>
      command-line option.</p>

    <p conref="../shared/impala_common.xml#common/usage_notes_blurb"/>
    <p conref="../shared/impala_common.xml#common/live_reporting_details"/>
    <p>
      For tracking the progress of an interactive query through
      all phases of processing, see <xref href="impala_live_summary.xml#live_summary"/>.
    </p>

    <p conref="../shared/impala_common.xml#common/restrictions_blurb"/>
    <p>
      Because the percentage complete figure is calculated using the number of
      issued and completed <q>scan ranges</q>, which occur while reading the table
      data, the progress bar might reach 100% before the query is entirely finished.
      For example, the query might do work to perform aggregations after all the
      table data has been read. If many of your queries fall into this category,
      consider using the <codeph>LIVE_SUMMARY</codeph> option for more granular progress
      reporting.
    </p>
    <p
      conref="../shared/impala_common.xml#common/impala_shell_progress_reports_compute_stats_caveat"/>
    <p conref="../shared/impala_common.xml#common/impala_shell_progress_reports_shell_only_caveat"/>

    <p conref="../shared/impala_common.xml#common/added_in_230"/>

    <p conref="../shared/impala_common.xml#common/example_blurb"/>
<codeblock><![CDATA[[localhost:21000] > select count(*) from customer;
+----------+
| count(*) |
+----------+
| 150000   |
+----------+
[localhost:21000] > select count(*) from customer t1 cross join customer t2;
[###################################                                   ] 50%
[######################################################################] 100%

]]>
</codeblock>

    <p conref="../shared/impala_common.xml#common/live_progress_live_summary_asciinema"/>

  </conbody>
</concept>