drill-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Deneche A. Hakim (JIRA)" <j...@apache.org>
Subject [jira] [Created] (DRILL-3397) over(partition by A order by A) should be optimized to over(partition by A)
Date Fri, 26 Jun 2015 17:27:04 GMT
Deneche A. Hakim created DRILL-3397:
---------------------------------------

             Summary: over(partition by A order by A) should be optimized to over(partition
by A)
                 Key: DRILL-3397
                 URL: https://issues.apache.org/jira/browse/DRILL-3397
             Project: Apache Drill
          Issue Type: Improvement
          Components: Query Planning & Optimization
            Reporter: Deneche A. Hakim
            Assignee: Jinfeng Ni
             Fix For: 1.2.0


although the following queries return the same results, they have different plans: 
{noformat}
EXPLAIN PLAN FOR SELECT SUM(salary) OVER(PARTITION BY position_id) FROM cp.`employee.json`;

00-00    Screen
00-01      Project(EXPR$0=[CASE(>($2, 0), $3, null)])
00-02        Window(window#0=[window(partition {1} order by [] range between UNBOUNDED PRECEDING
and UNBOUNDED FOLLOWING aggs [COUNT($0), $SUM0($0)])])
00-03          SelectionVectorRemover
00-04            Sort(sort0=[$1], dir0=[ASC])
00-05              Project(salary=[$1], position_id=[$0])
00-06                Scan(groupscan=[EasyGroupScan [selectionRoot=/employee.json, numFiles=1,
columns=[`salary`, `position_id`], files=[classpath:/employee.json]]])
{noformat}

{noformat}
EXPLAIN PLAN FOR SELECT SUM(salary) OVER(PARTITION BY position_id ORDER BY position_id) FROM
cp.`employee.json`;

00-00    Screen
00-01      Project(EXPR$0=[CASE(>($2, 0), $3, null)])
00-02        Window(window#0=[window(partition {1} order by [1] range between UNBOUNDED PRECEDING
and CURRENT ROW aggs [COUNT($0), $SUM0($0)])])
00-03          SelectionVectorRemover
00-04            Sort(sort0=[$1], sort1=[$1], dir0=[ASC], dir1=[ASC])
00-05              Project(salary=[$1], position_id=[$0])
00-06                Scan(groupscan=[EasyGroupScan [selectionRoot=/employee.json, numFiles=1,
columns=[`salary`, `position_id`], files=[classpath:/employee.json]]])
{noformat}

Drill should detect such cases and remove the order-by from the plan.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message