[jira] [Resolved] (IMPALA-4961) Allow Union node passthrough in more advanced cases

["Tim Armstrong (Jira)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/IMPALA-4961?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Tim Armstrong resolved IMPALA-4961.
-----------------------------------
    Resolution: Later

Unclear that many workloads would benefit from it.

> Allow Union node passthrough in more advanced cases
> ---------------------------------------------------
>
>                 Key: IMPALA-4961
>                 URL: https://issues.apache.org/jira/browse/IMPALA-4961
>             Project: IMPALA
>          Issue Type: New Feature
>          Components: Backend, Frontend
>    Affects Versions: Impala 2.9.0
>            Reporter: Taras Bobrovytsky
>            Priority: Major
>              Labels: ramp-up
>
> It should be possible to pass through rows without materialization in the following cases:
> # If both union branches have joins, but the resulting tuple layout is identical.
> # If the same column is referenced in the select list multiple times, for example:
> {code}
> select id, id from alltypes union select id, id from alltypestiny
> {code}



--
This message was sent by Atlassian Jira
(v8.3.4#803005)