You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues-all@impala.apache.org by "Tim Armstrong (JIRA)" <ji...@apache.org> on 2019/04/25 00:18:00 UTC
[jira] [Resolved] (IMPALA-7843) MT_DOP should be configurable per
subquery
[ https://issues.apache.org/jira/browse/IMPALA-7843?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Tim Armstrong resolved IMPALA-7843.
-----------------------------------
Resolution: Won't Do
I don't think this is viable to implement.
> MT_DOP should be configurable per subquery
> ------------------------------------------
>
> Key: IMPALA-7843
> URL: https://issues.apache.org/jira/browse/IMPALA-7843
> Project: IMPALA
> Issue Type: Improvement
> Reporter: Jon Apgar
> Priority: Major
>
> MT_DOP > 0 will cause queries with JOIN statements to fail, however the *subqueries* within the main query _might_ otherwise have been able to run successfully with MT_DOP > 0.
> A use-case for subqueries may be to limit the size of complex joins or eliminate redundant aggregation in the outer query, By allowing MT_DOP > 0 on subqueries you could significantly speed up the entire query.
> MT_DOP is not the only session variable which may be effectively configured per subquery. Perhaps there should be a way of specifying applicable variables within the select statement of a query.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-all-unsubscribe@impala.apache.org
For additional commands, e-mail: issues-all-help@impala.apache.org