maropu commented on a change in pull request #18576: [SPARK-21351][SQL] Update
nullability based on children's output
URL: https://github.com/apache/spark/pull/18576#discussion_r244072098
##########
File path:
sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/Optimizer.scala
##########
@@ -153,7 +153,9 @@ abstract class Optimizer(sessionCatalog: SessionCatalog)
RewritePredicateSubquery,
ColumnPruning,
CollapseProject,
- RemoveRedundantProject)
+ RemoveRedundantProject) :+
+ Batch("UpdateAttributeReferences", Once,
+ UpdateNullabilityInAttributeReferences)
Review comment:
yea, I have the same opinion with @gatorsmile; `FixNullability` is related
to the correctness, but `UpdateNullabilityInAttributeReferences` is not (just
for optimization).
@gatorsmile I think we haven't checked actual performance benefits (e.g.,
wall time) from the rule now. I just assume that this rule could generate
better code from the code generator.
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
[email protected]
With regards,
Apache Git Services
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
