[
https://issues.apache.org/jira/browse/IMPALA-13587?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Steve Carlin reassigned IMPALA-13587:
-------------------------------------
Assignee: Steve Carlin
> Calcite planner: outer join not aggregating nulls properly
> ----------------------------------------------------------
>
> Key: IMPALA-13587
> URL: https://issues.apache.org/jira/browse/IMPALA-13587
> Project: IMPALA
> Issue Type: Sub-task
> Reporter: Steve Carlin
> Assignee: Steve Carlin
> Priority: Major
>
> The following query is producing incorrect results:
> select t2.int_col y from alltypessmall t1 left outer join alltypestiny t2 on
> t1.int_col = t2.int_col group by 1
> ... due to nulls not being aggregated properly on multiple nodes. This is
> because the value equivalency graph is being set for the join conjunct on an
> outer join. When a hash join partition node is being used, there is an
> optimization that skips the aggregation step that combines groups across
> nodes if, based on the value transfer graph, it deduces that all data for the
> partition column is being sent to the same node.
> The bug here is that even though an outer join is using an equi-conjunct, the
> left and right side are different when data is not found on the outer join
> side, where it becomse null.
> The fix is to avoid registering the equi-conjunct if the values are not
> always equal.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
