cloud-fan commented on a change in pull request #31368:
URL: https://github.com/apache/spark/pull/31368#discussion_r565879134



##########
File path: 
sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/catalog/SessionCatalog.scala
##########
@@ -844,18 +844,41 @@ class SessionCatalog(
     }
   }
 
+  def getTempViewSchema(plan: LogicalPlan): StructType = {
+    plan match {
+      case viewInfo: TemporaryViewRelation => viewInfo.tableMeta.schema
+      case v => v.schema
+    }
+  }
+
   private def fromCatalogTable(metadata: CatalogTable, isTempView: Boolean): 
View = {
-    val viewText = metadata.viewText.getOrElse(sys.error("Invalid view without 
text."))
+    val viewText = metadata.viewText.getOrElse {
+      throw new IllegalStateException("Invalid view without text.")
+    }
     val viewConfigs = metadata.viewSQLConfigs
-    val viewPlan =
+    val parsedPlan =
       SQLConf.withExistingConf(View.effectiveSQLConf(viewConfigs, isTempView = 
isTempView)) {
         parser.parsePlan(viewText)
       }
-    View(
-      desc = metadata,
-      isTempView = isTempView,
-      output = metadata.schema.toAttributes,
-      child = viewPlan)
+    val viewColumnNames = metadata.viewQueryColumnNames
+    val viewPlan = if (viewColumnNames.nonEmpty) {
+      assert(viewColumnNames.length == metadata.schema.length)
+      // For view queries like `SELECT * FROM t`, the schema of the referenced 
table/view may
+      // change after the view has been created. We need to add an extra 
SELECT to pick the columns
+      // according to the recorded column names (to get the correct view 
column ordering and omit
+      // the extra columns that we don't require), add UpCast (to make sure 
the type change is
+      // safe) and Alias according to the schema in the catalog.
+      val projectList = viewColumnNames.zip(metadata.schema).map { case (col, 
field) =>
+        Alias(UpCast(UnresolvedAttribute.quoted(col), field.dataType), 
field.name)(
+          explicitMetadata = Some(field.metadata))
+      }
+      Project(projectList, parsedPlan)

Review comment:
       yea




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