[jira] [Assigned] (SPARK-19350) Cardinality estimation of Limit and Sample
[ https://issues.apache.org/jira/browse/SPARK-19350?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Xiao Li reassigned SPARK-19350: --- Assignee: Zhenhua Wang > Cardinality estimation of Limit and Sample > -- > > Key: SPARK-19350 > URL: https://issues.apache.org/jira/browse/SPARK-19350 > Project: Spark > Issue Type: Sub-task > Components: SQL >Reporter: Zhenhua Wang >Assignee: Zhenhua Wang > Fix For: 2.2.0 > > > Currently, LocalLimit/GlobalLimit/Sample propagates the same row count and > column stats from its child, which is incorrect. > We can get the correct rowCount in Statistics for Limit/Sample whether cbo is > enabled or not. And column stats should not be propagated because we don't > know the distribution of columns after Limit or Sample. -- This message was sent by Atlassian JIRA (v6.3.15#6346) - To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org
[jira] [Assigned] (SPARK-19350) Cardinality estimation of Limit and Sample
[ https://issues.apache.org/jira/browse/SPARK-19350?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Apache Spark reassigned SPARK-19350: Assignee: Apache Spark > Cardinality estimation of Limit and Sample > -- > > Key: SPARK-19350 > URL: https://issues.apache.org/jira/browse/SPARK-19350 > Project: Spark > Issue Type: Sub-task > Components: SQL >Reporter: Zhenhua Wang >Assignee: Apache Spark > > Currently, LocalLimit/GlobalLimit/Sample propagates the same row count and > column stats from its child, which is incorrect. > We can get the correct rowCount in Statistics for Limit/Sample whether cbo is > enabled or not. And column stats should not be propagated because we don't > know the distribution of columns after Limit or Sample. -- 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
[jira] [Assigned] (SPARK-19350) Cardinality estimation of Limit and Sample
[ https://issues.apache.org/jira/browse/SPARK-19350?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Apache Spark reassigned SPARK-19350: Assignee: (was: Apache Spark) > Cardinality estimation of Limit and Sample > -- > > Key: SPARK-19350 > URL: https://issues.apache.org/jira/browse/SPARK-19350 > Project: Spark > Issue Type: Sub-task > Components: SQL >Reporter: Zhenhua Wang > > Currently, LocalLimit/GlobalLimit/Sample propagates the same row count and > column stats from its child, which is incorrect. > We can get the correct rowCount in Statistics for Limit/Sample whether cbo is > enabled or not. And column stats should not be propagated because we don't > know the distribution of columns after Limit or Sample. -- 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
