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sunchao · sunchao · commit 12cd5981265d · 2021-01-19T10:20:15.000-08:00
diff --git a/sql/core/src/main/scala/org/apache/spark/sql/internal/CatalogImpl.scala b/sql/core/src/main/scala/org/apache/spark/sql/internal/CatalogImpl.scala
@@ -418,6 +418,11 @@ class CatalogImpl(sparkSession: SparkSession) extends Catalog {
 
   private def uncacheView(viewDef: LogicalPlan): Unit = {
     try {
+      // If view text is defined, it means we are not storing analyzed logical plan for the view
+      // and instead its behavior follows that of a permanent view (see SPARK-33142 for more
+      // details). Therefore, when uncaching the view we should also do in a cascade fashion, the
+      // same way as how a permanent view is handled. This also avoids a potential issue where a
+      // dependent view becomes invalid because of the above while its data is still cached.
       val viewText = viewDef match {
         case v: View => v.desc.viewText
         case _ => None
