[
https://issues.apache.org/jira/browse/FLINK-19896?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Jingsong Lee updated FLINK-19896:
---------------------------------
Priority: Major (was: Minor)
> Improve first-n-row fetching in the rank operator
> -------------------------------------------------
>
> Key: FLINK-19896
> URL: https://issues.apache.org/jira/browse/FLINK-19896
> Project: Flink
> Issue Type: Improvement
> Components: Table SQL / Runtime
> Reporter: Jun Zhang
> Assignee: Jun Zhang
> Priority: Major
> Labels: auto-deprioritized-major, pull-request-available
> Attachments: flink-19896.patch
>
>
> Currently Deduplicate operator only supports first-row deduplication (ordered
> by proc-time). In scenario of first-n-rows deduplication, the planner has to
> resort to Rank operator. However, Rank operator is less efficient than
> Deduplicate due to larger state and more state access.
> This issue proposes to extend DeduplicateKeepFirstRowFunction to support
> first-n-rows deduplication. And the original first-row deduplication would be
> a special case of first-n-rows deduplication.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
