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https://issues.apache.org/jira/browse/HIVE-26671?focusedWorklogId=820783&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-820783
]
ASF GitHub Bot logged work on HIVE-26671:
-----------------------------------------
Author: ASF GitHub Bot
Created on: 27/Oct/22 01:36
Start Date: 27/Oct/22 01:36
Worklog Time Spent: 10m
Work Description: scarlin-cloudera opened a new pull request, #3706:
URL: https://github.com/apache/hive/pull/3706
Grabbed the following query from the Impala test suite. It is a query run
off of tpcds tables, but it's not really super special. You will need a lot of
data to reproduce this, though.
select
l_orderkey,
min(l_shipdate) as flt,
count(distinct l_partkey) as cnl
from lineitem
group by l_orderkey order by l_orderkey limit 2;
The issue is with the Top N Key operator optimizer. The Top N Key operator
is the first operator after the Table Scan. The sort key is on both the
l_orderkey and l_partkey columns, but this means that the second sort key might
not be forwarded.
The fix was that we need to pick the correct Top N Key operator when pushing
down conflicting Top N Key operators.
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q tests were fixed in the process so no new q tests were added.
Issue Time Tracking
-------------------
Worklog Id: (was: 820783)
Remaining Estimate: 0h
Time Spent: 10m
> Incorrect results for group by/order by/limit query with 2 aggregates
> ---------------------------------------------------------------------
>
> Key: HIVE-26671
> URL: https://issues.apache.org/jira/browse/HIVE-26671
> Project: Hive
> Issue Type: Bug
> Components: Operators
> Reporter: Steve Carlin
> Assignee: Steve Carlin
> Priority: Major
> Time Spent: 10m
> Remaining Estimate: 0h
>
> Grabbed this query from the Impala test suite. It is a query run off of
> tpcds tables, but it's not really super special. You will need a lot of data
> to reproduce this, though.
> select
> l_orderkey,
> min(l_shipdate) as flt,
> count(distinct l_partkey) as cnl
> from lineitem
> group by l_orderkey order by l_orderkey limit 2;
> The issue is with the Top N Key operator optimizer. The Top N Key operator is
> the first operator after the Table Scan. The sort key is on both the
> l_orderkey and l_partkey columns, but this means that the second sort key
> might not be forwarded.
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