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

Posted to issues@kylin.apache.org by "Zhong Yanghong (JIRA)" <ji...@apache.org> on 2017/12/01 09:40:00 UTC

[jira] [Commented] (KYLIN-2867) split large fuzzy Key set

    [ https://issues.apache.org/jira/browse/KYLIN-2867?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16274170#comment-16274170 ] 

Zhong Yanghong commented on KYLIN-2867:
---------------------------------------

Need to add a trigger

> split large fuzzy Key set
> -------------------------
>
>                 Key: KYLIN-2867
>                 URL: https://issues.apache.org/jira/browse/KYLIN-2867
>             Project: Kylin
>          Issue Type: Improvement
>          Components: Query Engine
>            Reporter: Zhong Yanghong
>            Assignee: Zhong Yanghong
>
> Too many fuzzy keys in one scan may downgrade the performance. Currently if the number of fuzzy keys exceeds a threshold, like 200, the scan will not use fuzzy key. However, this may also downgrade the performance. 
> There are many cases in eBay that the total number of fuzzy keys is around 1000. To deal with these cases, it's better to split the large fuzzy key set, like 5*200. Then for each subset, assign a scan. This strategy will increase the number of scan to reduce the number of fuzzy keys in each scan to improve the total performance.



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)