[jira] [Closed] (PHOENIX-4618) Optimize out order-by on sort-merge-join when possible

["Chinmay Kulkarni (Jira)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/PHOENIX-4618?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Chinmay Kulkarni closed PHOENIX-4618.
-------------------------------------

Bulk closing Jiras for the 4.15.0 release.

> Optimize out order-by on sort-merge-join when possible
> ------------------------------------------------------
>
>                 Key: PHOENIX-4618
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-4618
>             Project: Phoenix
>          Issue Type: Improvement
>            Reporter: Wei Xue
>            Assignee: Wei Xue
>            Priority: Major
>             Fix For: 4.15.0, 5.1.0
>
>
> To do this, \{{OrderPreservingTracker}} relies solely on primary keys for inferring alignment between order-by expressions and the input sortedness. To implement this improvement, we need to have extra information of sortedness which supports equivalent sorted expressions. For example,
> {code}SELECT * FROM T1 JOIN T2 ON T1.a = T2.a and T1.b = T2.b{code}
> The result of the sort-merge-join is sorted on (T1.a, T1.b) and (T2.a, T2.b) at the same time.
> Thus, both 1)
> {code}SELECT * FROM T1 JOIN T2 ON T1.a = T2.a and T1.b = T2.b ORDER BY T1.a, T1.b{code}
> and 2)
> {code}SELECT * FROM T1 JOIN T2 ON T1.a = T2.a and T1.b = T2.b ORDER BY T2.a, T2.b{code}
> should avoid doing an extra order-by after the sort-merge-join operation.



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