[ 
https://issues.apache.org/jira/browse/FLINK-12173?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17884050#comment-17884050
 ] 

Jim Hughes commented on FLINK-12173:
------------------------------------

I think we should address https://issues.apache.org/jira/browse/FLINK-34702 as 
we work on this ticket.

Separately, I'd suggest that we solve this ticket with a logical optimization 
rule which map the above pattern to a LogicalRank instead of Deduplicate 
directly.

> Optimize "SELECT DISTINCT" into Deduplicate with keep first row
> ---------------------------------------------------------------
>
>                 Key: FLINK-12173
>                 URL: https://issues.apache.org/jira/browse/FLINK-12173
>             Project: Flink
>          Issue Type: New Feature
>          Components: Table SQL / Planner
>            Reporter: Jark Wu
>            Priority: Major
>              Labels: auto-deprioritized-major, auto-deprioritized-minor
>
> The following distinct query can be optimized into deduplicate on keys "a, b, 
> c, d" and keep the first row.
> {code:sql}
> SELECT DISTINCT a, b, c, d;
> {code}
> We can optimize this query into Deduplicate to get a better performance than 
> GroupAggregate.



--
This message was sent by Atlassian Jira
(v8.20.10#820010)

Reply via email to