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apache · Mar 10, 2016 · 4dd3e66 · 4dd3e66
1 parent f8fd37f
commit 4dd3e66
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/Optimizer.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/Optimizer.scala
@@ -381,6 +381,7 @@ object ColumnPruning extends Rule[LogicalPlan] {
     // Can't prune the columns on LeafNode
     case p @ Project(_, l: LeafNode) => p
 
+    // Prune windowExpressions and child of Window
     case p @ Project(_, w: Window) if (w.outputSet -- p.references).nonEmpty =>
       val newWindowExprs = w.windowExpressions.filter(p.references.contains)
       val newGrandChild = prunedChild(w.child, w.references ++ p.references)