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https://issues.apache.org/jira/browse/PHOENIX-1456?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14213720#comment-14213720
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Eli Levine commented on PHOENIX-1456:
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Thanks for reporting, Maryann. Are 4.1 and 4.2 affected?

> Incorrect query results caused by reusing buffers in SpoolingResultIterator
> ---------------------------------------------------------------------------
>
>                 Key: PHOENIX-1456
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-1456
>             Project: Phoenix
>          Issue Type: Bug
>    Affects Versions: 3.0.0, 4.0.0, 5.0.0
>            Reporter: Maryann Xue
>   Original Estimate: 120h
>  Remaining Estimate: 120h
>
> The SpoolingResultIterator#OnDiskResultIterator switches between two 
> pre-allocated buffers as reading buffers for the tuple result, based on the 
> assumption that the outer ResultIterator consumes the returned tuple in a 
> streaming fashion and will never look back/forward outside 2-tuple span.
> However, some usages fail this assumption:
> 1. OrderedResultIterator: It adds all tuples into its MappedByteBufferQueue 
> on initialization, which is maintained by a priority queue before threshold 
> is reached and spooling to files. 
> This is not revealed in most test cases because, most importantly, 
> OrderedResultIterator is not commonly used on clientside (only 
> ClientProcessingPlan does)
> 2. Child/parent hash-join optimization, which uses a list of PK values to 
> create an InListExpression.
> It might be easy to walk around the second usage here though, but may need 
> more consideration on the first one.
> I am thinking to take away SpoolingResultIterator at all if there is an outer 
> ResultIterator being OrderedResultIterator.



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