richardc-db commented on code in PR #50849:
URL: https://github.com/apache/spark/pull/50849#discussion_r2098816399
##########
sql/core/src/main/scala/org/apache/spark/sql/execution/ExistingRDD.scala:
##########
@@ -319,3 +319,46 @@ case class RDDScanExec(
override def getStream: Option[SparkDataStream] = stream
}
+
+/**
+ * A physical plan node for `OneRowRelation` for scans with no 'FROM' clause.
+ *
+ * We do not extend `RDDScanExec` in order to avoid complexity due to
`TreeNode.makeCopy` and
+ * `TreeNode`'s general use of reflection.
+ */
+case class OneRowRelationExec() extends LeafExecNode
+ with InputRDDCodegen {
+
+ override val nodeName: String = s"Scan OneRowRelation"
+
+ override val output: Seq[Attribute] = Nil
+
+ private val emptyRow: InternalRow = InternalRow.empty
+
+ private val rdd = session.sparkContext.parallelize(Seq(emptyRow), 1)
+
+ override lazy val metrics = Map(
+ "numOutputRows" -> SQLMetrics.createMetric(sparkContext, "number of output
rows"))
Review Comment:
hmm, I guess we might not _need_ it, but again I would prefer to keep it as
is to avoid breaking anyone that might rely on it. I also think that it might
be relevant for Spark UI to show the number of rows between operators
--
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
