maropu commented on a change in pull request #27231: [SPARK-28478][SQL] Remove redundant null checks URL: https://github.com/apache/spark/pull/27231#discussion_r376925624
########## File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/expressions.scala ########## @@ -434,6 +434,27 @@ object SimplifyConditionals extends Rule[LogicalPlan] with PredicateHelper { case _ => false } + /** + * Condition for redundant null check based on intolerant expressions. + * @param ifNullExpr expression that takes place if checkedExpr is null + * @param ifNotNullExpr expression that takes place if checkedExpr is not null + * @param checkedExpr expression that is checked for null value + */ + private def isRedundantNullCheck( + ifNullExpr: Expression, + ifNotNullExpr: Expression, + checkedExpr: Expression): Boolean = { + val isNullIntolerant = ifNotNullExpr.find { x => + !x.isInstanceOf[NullIntolerant] && x.find(e => e.semanticEquals(checkedExpr)).nonEmpty Review comment: Hmmm, that still looks complicated.. If we cannot avoid the complexity for the stronger condition, as another option, I think we can cover the simple case (`FiterExec.isNullIntolerant(ifNotNullExpr)`) only in this pr. If necessary, we might be able to optimize the condition in future work. I think keeping the code simple is more important. WDYT? ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org