kazuyukitanimura commented on a change in pull request #33930:
URL: https://github.com/apache/spark/pull/33930#discussion_r704639466
##########
File path:
sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/expressions.scala
##########
@@ -441,6 +456,24 @@ object BooleanSimplification extends Rule[LogicalPlan]
with PredicateHelper {
case Not(IsNull(e)) => IsNotNull(e)
case Not(IsNotNull(e)) => IsNull(e)
+
+ // Using Not(null) == null rules
+ case IsNull(Not(e)) => IsNull(e)
+ case IsNotNull(Not(e)) => IsNotNull(e)
+
+ // Using (Not(a) === b) == (a === Not(b)), (Not(a) <=> b) == (a <=>
Not(b)) rules
+ case EqualTo(Not(a), b) if canSimplifyNot(b) => EqualTo(a, Not(b))
Review comment:
For example of the `EqualTo(Not(a), b)` where `b = Not(c)`, it will
become `EqualTo(a, Not(b))` => `EqualTo(a, Not(Not(c)))` => `EqualTo(a, c)`
In addition, `if canSimplifyNot(b)` checks if the optimization can converge
that avoids the situation two conditions are returning to each other.
I plan to add those explanations to the comment.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
