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https://issues.apache.org/jira/browse/HIVE-21174?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16989213#comment-16989213
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Pablo Junge commented on HIVE-21174:
------------------------------------

Wiki updated from 

Current documentation shows:
----------------------------
Standard error allowed for NDV estimates, expressed in percentage. This 
provides a tradeoff between accuracy and compute cost. A lower value for the 
error indicates higher accuracy and a higher compute cost. (NDV means number of 
distinct values.)

 

To 

----------------

The standard error allowed for NDV estimates, expressed in percentage. This 
provides a tradeoff between accuracy and compute cost. A lower value for the 
error indicates higher accuracy and a higher compute cost. (NDV means the 
number of distinct values.). It only affects the FM-Sketch (not the HLL 
algorithm which is the default), where it computes the number of necessary 
bitvectors to achieve the accuracy.

 

> hive.stats.ndv.error parameter documentation issue
> --------------------------------------------------
>
>                 Key: HIVE-21174
>                 URL: https://issues.apache.org/jira/browse/HIVE-21174
>             Project: Hive
>          Issue Type: Improvement
>          Components: Documentation
>    Affects Versions: 2.0.0, 2.0.1, 2.0.2, 2.1.0, 2.1.1, 2.1.2, 2.2.0, 2.3.0, 
> 3.0.0, 2.4.0, 2.2.1, 2.3.1, 2.3.2, 2.3.3, 3.1.0, 3.0.1, 3.10, 3.2.0, 3.1.1, 
> 2.3.4, 3.1.2
>            Reporter: Pablo Junge
>            Assignee: Pablo Junge
>            Priority: Major
>             Fix For: 2.0.0, 2.0.1, 2.0.2, 2.1.0, 2.1.1, 2.1.2, 2.2.0, 2.3.0, 
> 3.0.0, 2.4.0, 2.2.1, 2.3.1, 2.3.2, 2.3.3, 3.1.0, 3.0.1, 3.10, 3.2.0, 3.1.1, 
> 2.3.4
>
>
> Hive documentation for hive.stats.ndv.error does not specify that 
> hive.stats.ndv.error will only affect FM Sketch and not HLL.
>  
> https://cwiki.apache.org/confluence/display/Hive/Configuration+Properties



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