[SPARK-11596][SQL] In TreeNode's argString, if a TreeNode is not a child of the current TreeNode, we should only return the simpleString.

yhuai · marmbrus · commit 1b3db967e05a · 2015-12-01T17:19:09.000-08:00
In TreeNode's argString, if a TreeNode is not a child of the current TreeNode, we will only return the simpleString. I tested the [following case provided by Cristian](https://issues.apache.org/jira/browse/SPARK-11596?focusedCommentId=15019241&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-15019241). ``` val c = (1 to 20).foldLeft[Option[DataFrame]] (None) { (curr, idx) => println(s"PROCESSING >>>>>>>>>>> $idx") val df = sqlContext.sparkContext.parallelize((0 to 10).zipWithIndex).toDF("A", "B") val union = curr.map(_.unionAll(df)).getOrElse(df) union.cache() Some(union) } c.get.explain(true) ``` Without the change, `c.get.explain(true)` took 100s. With the change, `c.get.explain(true)` took 26ms. https://issues.apache.org/jira/browse/SPARK-11596 Author: Yin Huai <yhuai@databricks.com> Closes apache#10079 from yhuai/SPARK-11596. (cherry picked from commit e96a70d) Signed-off-by: Michael Armbrust <michael@databricks.com>
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/trees/TreeNode.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/trees/TreeNode.scala
@@ -380,7 +380,7 @@ abstract class TreeNode[BaseType <: TreeNode[BaseType]] extends Product {
   /** Returns a string representing the arguments to this node, minus any children */
   def argString: String = productIterator.flatMap {
     case tn: TreeNode[_] if containsChild(tn) => Nil
-    case tn: TreeNode[_] if tn.toString contains "\n" => s"(${tn.simpleString})" :: Nil
+    case tn: TreeNode[_] => s"(${tn.simpleString})" :: Nil
     case seq: Seq[BaseType] if seq.toSet.subsetOf(children.toSet) => Nil
     case seq: Seq[_] => seq.mkString("[", ",", "]") :: Nil
     case set: Set[_] => set.mkString("{", ",", "}") :: Nil
