kazuyukitanimura commented on a change in pull request #33930: URL: https://github.com/apache/spark/pull/33930#discussion_r706584087
########## File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/expressions.scala ########## @@ -441,6 +456,25 @@ object BooleanSimplification extends Rule[LogicalPlan] with PredicateHelper { case Not(IsNull(e)) => IsNotNull(e) case Not(IsNotNull(e)) => IsNull(e) + + // Move `Not` from one side of `EqualTo`/`EqualNullSafe` to the other side if it's beneficial. + // E.g. `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. + case EqualTo(Not(a), b) if canSimplifyNot(b) => EqualTo(a, Not(b)) Review comment: We can but the extra checks are a bit redundant because all `Not` optimizations are listed above this line of the case match. Do you feel we must need the extra checks? @dbtsai It is actually does not matter `a` or `b` gets simplified because `canSimplifyNot()` promises it will be simpler than current form. -- 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: reviews-unsubscr...@spark.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org