docs/topics/impala_having.xml

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

  <title>HAVING Clause</title>
  <prolog>
    <metadata>
      <data name="Category" value="Impala"/>
      <data name="Category" value="SQL"/>
      <data name="Category" value="Querying"/>
      <data name="Category" value="Aggregate Functions"/>
      <data name="Category" value="Developers"/>
      <data name="Category" value="Data Analysts"/>
    </metadata>
  </prolog>

  <conbody>

    <p>
      Performs a filter operation on a <codeph>SELECT</codeph> query, by examining the results of aggregation
      functions rather than testing each individual table row. Therefore, it is always used in conjunction with a
      function such as <codeph><xref href="impala_count.xml#count">COUNT()</xref></codeph>,
      <codeph><xref href="impala_sum.xml#sum">SUM()</xref></codeph>,
      <codeph><xref href="impala_avg.xml#avg">AVG()</xref></codeph>,
      <codeph><xref href="impala_min.xml#min">MIN()</xref></codeph>, or
      <codeph><xref href="impala_max.xml#max">MAX()</xref></codeph>, and typically with the
      <codeph><xref href="impala_group_by.xml#group_by">GROUP BY</xref></codeph> clause also.
    </p>

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

    <p rev="2.0.0">
      The filter expression in the <codeph>HAVING</codeph> clause cannot include a scalar subquery.
    </p>

    <p conref="../shared/impala_common.xml#common/related_info"/>
    <p>
      <xref href="impala_select.xml#select"/>,
      <xref href="impala_group_by.xml#group_by"/>,
      <xref href="impala_aggregate_functions.xml#aggregate_functions"/>
    </p>

  </conbody>
</concept>