[
https://issues.apache.org/jira/browse/DRILL-883?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Jacques Nadeau resolved DRILL-883.
----------------------------------
Resolution: Fixed
> Wrong result when projecting certain columns if subquery and outer query have
> the same table
> ---------------------------------------------------------------------------------------------
>
> Key: DRILL-883
> URL: https://issues.apache.org/jira/browse/DRILL-883
> Project: Apache Drill
> Issue Type: Bug
> Reporter: Aman Sinha
> Assignee: Jacques Nadeau
>
> In the following query, projecting n_regionkey in the outer query produces
> wrong results. The outer query and subquery both reference nation table,
> although they should be separate instances. Note that the Scan of nation in
> the outer query is project the wrong column (n_nationkey instead of
> n_regionkey). That's causing the wrong results. One other observation:
> disabling the push project into scan rule gives correct results.
> 1 row selected (0.344 seconds)
> 0: jdbc:drill:zk=local> explain plan for select n1.n_regionkey from nation
> n1, (select n_nationkey from nation) as n2 where n1.n_nationkey =
> n2.n_nationkey;
> +------------+------------+
> | text | json |
> +------------+------------+
> | 00-00 Screen
> 00-01 UnionExchange
> 01-01 Project(n_regionkey=[$2])
> 01-02 HashJoin(condition=[=($1, $3)], joinType=[inner])
> 01-04 HashToRandomExchange(dist0=[[$1]])
> 02-01 Scan(groupscan=[ParquetGroupScan
> [entries=[ReadEntryWithPath [path=file:/Users/asinha/data/tpchmulti/nation]],
> selectionRoot=/Users/asinha/data/tpchmulti/nation, columns=[SchemaPath
> [`n_nationkey`]]]])
> 01-03 Project(n_nationkey0=[$0])
> 01-05 HashToRandomExchange(dist0=[[$0]])
> 03-01 Project(n_nationkey=[$1])
> 03-02 Scan(groupscan=[ParquetGroupScan
> [entries=[ReadEntryWithPath [path=file:/Users/asinha/data/tpchmulti/nation]],
> selectionRoot=/Users/asinha/data/tpchmulti/nation, columns=[SchemaPath
> [`n_nationkey`]]]])
> 0: jdbc:drill:zk=local> select n1.n_regionkey from nation n1, (select
> n_nationkey from nation) as n2 where n1.n_nationkey = n2.n_nationkey;
> +-------------+
> | n_regionkey |
> +-------------+
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> | null |
> +-------------+
> 25 rows selected (0.538 seconds)
--
This message was sent by Atlassian JIRA
(v6.2#6252)
