[ https://issues.apache.org/jira/browse/SPARK-23375?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Marco Gaido updated SPARK-23375: -------------------------------- Description: As pointed out in SPARK-23368, as of now there is no rule to remove the Sort operator on an already sorted plan, ie. if we have a query like: {code} SELECT b FROM ( SELECT a, b FROM table1 ORDER BY a ) t ORDER BY a {code} The sort is actually executed twice, even though it is not needed. was: As pointed out in SPARK-23368, as of now there is no rule to remove the Sort operator on an already sorted plan, ie. if we have a query like: {{code}} SELECT b FROM ( SELECT a, b FROM table1 ORDER BY a ) t ORDER BY a {{code}} The sort is actually executed twice, even though it is not needed. > Optimizer should remove unneeded Sort > ------------------------------------- > > Key: SPARK-23375 > URL: https://issues.apache.org/jira/browse/SPARK-23375 > Project: Spark > Issue Type: Improvement > Components: SQL > Affects Versions: 2.3.0 > Reporter: Marco Gaido > Priority: Minor > > As pointed out in SPARK-23368, as of now there is no rule to remove the Sort > operator on an already sorted plan, ie. if we have a query like: > {code} > SELECT b > FROM ( > SELECT a, b > FROM table1 > ORDER BY a > ) t > ORDER BY a > {code} > The sort is actually executed twice, even though it is not needed. -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org