[ https://issues.apache.org/jira/browse/SPARK-21979?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Apache Spark reassigned SPARK-21979: ------------------------------------ Assignee: Apache Spark > Improve QueryPlanConstraints framework > -------------------------------------- > > Key: SPARK-21979 > URL: https://issues.apache.org/jira/browse/SPARK-21979 > Project: Spark > Issue Type: Bug > Components: SQL > Affects Versions: 2.2.0 > Reporter: Gengliang Wang > Assignee: Apache Spark > Priority: Critical > > Improve QueryPlanConstraints framework, make it robust and simple. > In apache/spark#15319, constraints for expressions like a = f(b, c) is > resolved. > However, for expressions like > a = f(b, c) && c = g(a, b) > The current QueryPlanConstraints framework will produce non-converging > constraints. > Essentially, the problem is caused by having both the name and child of > aliases in the same constraint set. We infer constraints, and push down > constraints as predicates in filters, later on these predicates are > propagated as constraints, etc.. > Simply using the alias names only can resolve these problems. The size of > constraints is reduced without losing any information. We can always get > these inferred constraints on child of aliases when pushing down filters. > Also, the EqualNullSafe between name and child in propagating alias is > meaningless > allConstraints += EqualNullSafe(e, a.toAttribute) > It just produce redundant constraints. -- This message was sent by Atlassian JIRA (v6.4.14#64029) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org