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https://issues.apache.org/jira/browse/IMPALA-8205?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16769691#comment-16769691
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Piotr Findeisen commented on IMPALA-8205:
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[~tarmstrong] what about simply calculating these values?
I think Impala would not have a problem with calculating them without too much
of an overhead.
Even if Impala does not use these stats, this would make Impala users more
happy that they are calculating stats with Impala.
([~wuchang1989] would it be a viable workaround to calculate stats with Hive
for tables containing boolean columns?)
> Illegal statistics for numFalse and numTrue
> -------------------------------------------
>
> Key: IMPALA-8205
> URL: https://issues.apache.org/jira/browse/IMPALA-8205
> Project: IMPALA
> Issue Type: Bug
> Reporter: wuchang
> Priority: Major
> Labels: impala, numFalse, numTrue, statistics
>
> When impala compute statistics, it set *numFalse = -1* and *numTrue = 1* when
> the statistic is missing;
> *-1* for *numFalse* will corrupt some query engine like Presto and there
> already exists some PR report and hotfix it :
> [presto-11859|https://github.com/prestodb/presto/pull/11859]
> *1* for *numTrue* is also unreasonable because we are not sure whether it
> indicates the real numTrue statistics or a missing statistics;
> Also, previously , the *nullCount* also use -1 to indicate its absence which
> also caused problem for Presto. Presto has to add a hotfix for
> it([presto-11549|https://github.com/prestodb/presto/pull/11549]) . But it is
> a fortunate that impala has fixed this bug;
> It is necessary to set to null when these statistics are absent instead of -1
> and 1.
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