You are viewing a plain text version of this content. The canonical link for it is here.

Posted to issues@flink.apache.org by "Hequn Cheng (JIRA)" <ji...@apache.org> on 2018/05/23 16:22:00 UTC

[jira] [Commented] (FLINK-9422) Dedicated operator for UNION on streaming tables with time attributes

    [ https://issues.apache.org/jira/browse/FLINK-9422?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16487575#comment-16487575 ] 

Hequn Cheng commented on FLINK-9422:
------------------------------------

Hi [~fhueske]  [~RuidongLi] , I am not sure if we need to add a dedicated {{UNION}} operator since we can solve it by [FLNIK-8566|https://issues.apache.org/jira/browse/FLINK-8566] and [FLINK-8594|https://issues.apache.org/jira/browse/FLINK-8594], right?

> Dedicated operator for UNION on streaming tables with time attributes
> ---------------------------------------------------------------------
>
>                 Key: FLINK-9422
>                 URL: https://issues.apache.org/jira/browse/FLINK-9422
>             Project: Flink
>          Issue Type: Improvement
>          Components: Table API &amp; SQL
>            Reporter: Fabian Hueske
>            Assignee: Ruidong Li
>            Priority: Minor
>
> We can implement a dedicated operator for a {{UNION}} operator on tables with time attributes. Currently, {{UNION}} is translated into a {{UNION ALL}} and a subsequent {{GROUP BY}} on all attributes without aggregation functions. The state of the grouping operator is only clean up using state retention timers. 
> The dedicated operator would leverage the monotonicity property of the time attribute and watermarks to automatically clean up its state.



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)