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https://issues.apache.org/jira/browse/TRAFODION-2259?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Prashanth Vasudev closed TRAFODION-2259.
----------------------------------------
    Resolution: Fixed

> Sort TopN operator
> ------------------
>
>                 Key: TRAFODION-2259
>                 URL: https://issues.apache.org/jira/browse/TRAFODION-2259
>             Project: Apache Trafodion
>          Issue Type: Improvement
>          Components: sql-exe
>    Affects Versions: 2.1-incubating
>            Reporter: Prashanth Vasudev
>            Assignee: Prashanth Vasudev
>
> Sort operator consumes all records before producing sorted records. For 
> certain use cases where only Top N records are required, today sort consumes 
> all records into memory and overflows( spills ) to disk. This impacts 
> performance. 
> if topN is pushed down to sort, only required memory can be allocated and 
> sort would only hold topN records in memory. Once all the records are read, 
> sorted records in topN is returned. 



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