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https://issues.apache.org/jira/browse/HIVE-13233?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15186751#comment-15186751
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Jesus Camacho Rodriguez commented on HIVE-13233:
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[~ashutoshc], thanks for checking.
1) <= and < are also taken into account (line 747 in StatsRulesProcFactory,
thus _else_ block in {{evaluateComparator}} refers to them).
2) Checking nested expressions is already taken care of by
{{evaluateChildExpr}}. In fact, we call {{evaluateComparator}} only when we
have found an expression a _CMP_ b, where _CMP_ is >=, >, <=, or <. Previously,
we were just returning 1/3 of the rows for these cases.
> Use min and max values to estimate better stats for comparison operators
> ------------------------------------------------------------------------
>
> Key: HIVE-13233
> URL: https://issues.apache.org/jira/browse/HIVE-13233
> Project: Hive
> Issue Type: Bug
> Components: Statistics
> Affects Versions: 2.1.0
> Reporter: Jesus Camacho Rodriguez
> Assignee: Jesus Camacho Rodriguez
> Attachments: HIVE-13233.patch
>
>
> We should benefit from the min/max values for each column to calculate more
> precisely the number of rows produced by expressions with comparison operators
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