[GitHub] cloud-fan commented on a change in pull request #23566: [SPARK-26637][SQL] Makes GetArrayItem nullability more precise

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

cloud-fan commented on a change in pull request #23566: [SPARK-26637][SQL] Makes GetArrayItem nullability more precise
URL: https://github.com/apache/spark/pull/23566#discussion_r249366878
 
 

 ##########
 File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/complexTypeExtractors.scala
 ##########
 @@ -233,7 +233,20 @@ case class GetArrayItem(child: Expression, ordinal: Expression)
   override def right: Expression = ordinal
 
   /** `Null` is returned for invalid ordinals. */
-  override def nullable: Boolean = true
+  override def nullable: Boolean = if (ordinal.foldable && !ordinal.nullable) {
+    val intOrdinal = ordinal.eval().asInstanceOf[Number].intValue()
+    child match {
+      case CreateArray(ar) if intOrdinal < ar.length =>
+        ar(intOrdinal).nullable
+      case GetArrayStructFields(CreateArray(ar), _, _, _, containsNull)
+          if intOrdinal < ar.length =>
+        containsNull
 
 Review comment:
   should this be `ar(intOrdinal).nullable`?

----------------------------------------------------------------
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:
users@infra.apache.org


With regards,
Apache Git Services

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