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From "Zhenhua Wang (JIRA)" <j...@apache.org>
Subject [jira] [Updated] (SPARK-21322) support histogram in filter cardinality estimation
Date Mon, 11 Sep 2017 12:16:03 GMT

     [ https://issues.apache.org/jira/browse/SPARK-21322?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Zhenhua Wang updated SPARK-21322:
---------------------------------
    Issue Type: Sub-task  (was: Improvement)
        Parent: SPARK-21975

> support histogram in filter cardinality estimation
> --------------------------------------------------
>
>                 Key: SPARK-21322
>                 URL: https://issues.apache.org/jira/browse/SPARK-21322
>             Project: Spark
>          Issue Type: Sub-task
>          Components: SQL
>    Affects Versions: 2.1.0
>            Reporter: Ron Hu
>
> Histogram is effective in dealing with skewed distribution.  After we generate histogram
information for column statistics, we need to adjust filter estimation based on histogram
data structure.



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