[GitHub] [spark] cloud-fan commented on a change in pull request #35220: [SPARK-37922][SQL] Improve `SimplifyCasts` to remove useless cast

[GitBox <gi...@apache.org>]

cloud-fan commented on a change in pull request #35220:
URL: https://github.com/apache/spark/pull/35220#discussion_r785694477



##########
File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/expressions.scala
##########
@@ -1037,6 +1037,9 @@ object SimplifyCasts extends Rule[LogicalPlan] {
   def apply(plan: LogicalPlan): LogicalPlan = plan.transformAllExpressionsWithPruning(
     _.containsPattern(CAST), ruleId) {
     case Cast(e, dataType, _, _) if e.dataType == dataType => e
+    case c1 @ Cast(Cast(e, d2: DecimalType, _, _), d1: DecimalType, _, _)
+        if d1.isWiderThan(d2) && d2.isWiderThan(e.dataType) =>

Review comment:
       can we generalize it? I think the general idea is we can combine to "upcast" into one.




-- 
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-unsubscribe@spark.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org



---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscribe@spark.apache.org
For additional commands, e-mail: reviews-help@spark.apache.org