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Apache Spark commented on SPARK-16208: -------------------------------------- User 'dongjoon-hyun' has created a pull request for this issue: https://github.com/apache/spark/pull/13905 > Add `CollapseEmptyPlan` optimizer > --------------------------------- > > Key: SPARK-16208 > URL: https://issues.apache.org/jira/browse/SPARK-16208 > Project: Spark > Issue Type: Improvement > Components: SQL > Reporter: Dongjoon Hyun > Priority: Minor > > This issue adds a new logical optimizer, `CollapseEmptyPlan`, to collapse a > logical plain consisting of only empty LocalRelations. > **Before** > {code} > scala> sql("select a from (select explode(array(1,2,3)) a) where 1=0 group by > a having count(*)>1 order by a").explain > == Physical Plan == > *Sort [a#15 ASC], true, 0 > +- Exchange rangepartitioning(a#15 ASC, 200) > +- *Project [a#15] > +- *Filter (count(1)#17L > 1) > +- *HashAggregate(keys=[a#15], functions=[count(1)]) > +- Exchange hashpartitioning(a#15, 200) > +- *HashAggregate(keys=[a#15], functions=[partial_count(1)]) > +- Generate explode([1,2,3]), false, false, [a#15] > +- LocalTableScan <empty> > {code} > **After** > {code} > scala> sql("select a from (select explode(array(1,2,3)) a) where 1=0 group by > a having count(*)>1 order by a").explain > == Physical Plan == > LocalTableScan <empty>, [a#15] > {code} -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org