[jira] [Assigned] (SPARK-34514) Push down limit for LEFT SEMI and LEFT ANTI join
[ https://issues.apache.org/jira/browse/SPARK-34514?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Yuming Wang reassigned SPARK-34514: --- Assignee: Cheng Su (was: Apache Spark) > Push down limit for LEFT SEMI and LEFT ANTI join > > > Key: SPARK-34514 > URL: https://issues.apache.org/jira/browse/SPARK-34514 > Project: Spark > Issue Type: Improvement > Components: SQL >Affects Versions: 3.1.0 >Reporter: Cheng Su >Assignee: Cheng Su >Priority: Trivial > Fix For: 3.2.0 > > > I found out during code review of > [https://github.com/apache/spark/pull/31567|https://github.com/apache/spark/pull/31567,]( > [https://github.com/apache/spark/pull/31567#discussion_r577379572] ), where > we can push down limit to the left side of LEFT SEMI and LEFT ANTI join, if > the join condition is empty. > Why it's safe to push down limit: > The semantics of LEFT SEMI join without condition: > (1). if right side is non-empty, output all rows from left side. > (2). if right side is empty, output nothing. > > The semantics of LEFT ANTI join without condition: > (1). if right side is non-empty, output nothing. > (2). if right side is empty, output all rows from left side. > > With the semantics of output all rows from left side or nothing (all or > nothing), it's safe to push down limit to left side. > NOTE: LEFT SEMI / LEFT ANTI join with non-empty condition is not safe for > limit push down, because output can be a portion of left side rows. > > Physical operator for LEFT SEMI / LEFT ANTI join without condition - > [https://github.com/apache/spark/blob/master/sql/core/src/main/scala/org/apache/spark/sql/execution/joins/BroadcastNestedLoopJoinExec.scala#L200-L204] > . -- This message was sent by Atlassian Jira (v8.20.1#820001) - To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org
[jira] [Assigned] (SPARK-34514) Push down limit for LEFT SEMI and LEFT ANTI join
[ https://issues.apache.org/jira/browse/SPARK-34514?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Apache Spark reassigned SPARK-34514: Assignee: Apache Spark > Push down limit for LEFT SEMI and LEFT ANTI join > > > Key: SPARK-34514 > URL: https://issues.apache.org/jira/browse/SPARK-34514 > Project: Spark > Issue Type: Improvement > Components: SQL >Affects Versions: 3.1.0 >Reporter: Cheng Su >Assignee: Apache Spark >Priority: Trivial > > I found out during code review of > [https://github.com/apache/spark/pull/31567|https://github.com/apache/spark/pull/31567,]( > [https://github.com/apache/spark/pull/31567#discussion_r577379572] ), where > we can push down limit to the left side of LEFT SEMI and LEFT ANTI join, if > the join condition is empty. > Why it's safe to push down limit: > The semantics of LEFT SEMI join without condition: > (1). if right side is non-empty, output all rows from left side. > (2). if right side is empty, output nothing. > > The semantics of LEFT ANTI join without condition: > (1). if right side is non-empty, output nothing. > (2). if right side is empty, output all rows from left side. > > With the semantics of output all rows from left side or nothing (all or > nothing), it's safe to push down limit to left side. > NOTE: LEFT SEMI / LEFT ANTI join with non-empty condition is not safe for > limit push down, because output can be a portion of left side rows. > > Physical operator for LEFT SEMI / LEFT ANTI join without condition - > [https://github.com/apache/spark/blob/master/sql/core/src/main/scala/org/apache/spark/sql/execution/joins/BroadcastNestedLoopJoinExec.scala#L200-L204] > . -- This message was sent by Atlassian Jira (v8.3.4#803005) - To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org
[jira] [Assigned] (SPARK-34514) Push down limit for LEFT SEMI and LEFT ANTI join
[ https://issues.apache.org/jira/browse/SPARK-34514?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Apache Spark reassigned SPARK-34514: Assignee: Apache Spark > Push down limit for LEFT SEMI and LEFT ANTI join > > > Key: SPARK-34514 > URL: https://issues.apache.org/jira/browse/SPARK-34514 > Project: Spark > Issue Type: Improvement > Components: SQL >Affects Versions: 3.1.0 >Reporter: Cheng Su >Assignee: Apache Spark >Priority: Trivial > > I found out during code review of > [https://github.com/apache/spark/pull/31567|https://github.com/apache/spark/pull/31567,]( > [https://github.com/apache/spark/pull/31567#discussion_r577379572] ), where > we can push down limit to the left side of LEFT SEMI and LEFT ANTI join, if > the join condition is empty. > Why it's safe to push down limit: > The semantics of LEFT SEMI join without condition: > (1). if right side is non-empty, output all rows from left side. > (2). if right side is empty, output nothing. > > The semantics of LEFT ANTI join without condition: > (1). if right side is non-empty, output nothing. > (2). if right side is empty, output all rows from left side. > > With the semantics of output all rows from left side or nothing (all or > nothing), it's safe to push down limit to left side. > NOTE: LEFT SEMI / LEFT ANTI join with non-empty condition is not safe for > limit push down, because output can be a portion of left side rows. > > Physical operator for LEFT SEMI / LEFT ANTI join without condition - > [https://github.com/apache/spark/blob/master/sql/core/src/main/scala/org/apache/spark/sql/execution/joins/BroadcastNestedLoopJoinExec.scala#L200-L204] > . -- This message was sent by Atlassian Jira (v8.3.4#803005) - To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org
[jira] [Assigned] (SPARK-34514) Push down limit for LEFT SEMI and LEFT ANTI join
[ https://issues.apache.org/jira/browse/SPARK-34514?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Apache Spark reassigned SPARK-34514: Assignee: (was: Apache Spark) > Push down limit for LEFT SEMI and LEFT ANTI join > > > Key: SPARK-34514 > URL: https://issues.apache.org/jira/browse/SPARK-34514 > Project: Spark > Issue Type: Improvement > Components: SQL >Affects Versions: 3.1.0 >Reporter: Cheng Su >Priority: Trivial > > I found out during code review of > [https://github.com/apache/spark/pull/31567|https://github.com/apache/spark/pull/31567,]( > [https://github.com/apache/spark/pull/31567#discussion_r577379572] ), where > we can push down limit to the left side of LEFT SEMI and LEFT ANTI join, if > the join condition is empty. > Why it's safe to push down limit: > The semantics of LEFT SEMI join without condition: > (1). if right side is non-empty, output all rows from left side. > (2). if right side is empty, output nothing. > > The semantics of LEFT ANTI join without condition: > (1). if right side is non-empty, output nothing. > (2). if right side is empty, output all rows from left side. > > With the semantics of output all rows from left side or nothing (all or > nothing), it's safe to push down limit to left side. > NOTE: LEFT SEMI / LEFT ANTI join with non-empty condition is not safe for > limit push down, because output can be a portion of left side rows. > > Physical operator for LEFT SEMI / LEFT ANTI join without condition - > [https://github.com/apache/spark/blob/master/sql/core/src/main/scala/org/apache/spark/sql/execution/joins/BroadcastNestedLoopJoinExec.scala#L200-L204] > . -- This message was sent by Atlassian Jira (v8.3.4#803005) - To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org
