backport

Author: gatorsmile

python/pyspark/sql/dataframe.py

@@ -191,6 +191,23 @@ def createGlobalTempView(self, name):
         """
         self._jdf.createGlobalTempView(name)
 
+    @since(2.2)
+    def createOrReplaceGlobalTempView(self, name):
+        """Creates or replaces a global temporary view using the given name.
+
+        The lifetime of this temporary view is tied to this Spark application.
+
+        >>> df.createOrReplaceGlobalTempView("people")
+        >>> df2 = df.filter(df.age > 3)
+        >>> df2.createOrReplaceGlobalTempView("people")
+        >>> df3 = spark.sql("select * from global_temp.people")
+        >>> sorted(df3.collect()) == sorted(df2.collect())
+        True
+        >>> spark.catalog.dropGlobalTempView("people")
+
+        """
+        self._jdf.createOrReplaceGlobalTempView(name)
+
     @property
     @since(1.4)
     def write(self):

sql/core/src/main/scala/org/apache/spark/sql/Dataset.scala

@@ -2657,6 +2657,22 @@ class Dataset[T] private[sql](
     createTempViewCommand(viewName, replace = false, global = true)
   }
 
+  /**
+   * Creates or replaces a global temporary view using the given name. The lifetime of this
+   * temporary view is tied to this Spark application.
+   *
+   * Global temporary view is cross-session. Its lifetime is the lifetime of the Spark application,
+   * i.e. it will be automatically dropped when the application terminates. It's tied to a system
+   * preserved database `_global_temp`, and we must use the qualified name to refer a global temp
+   * view, e.g. `SELECT * FROM _global_temp.view1`.
+   *
+   * @group basic
+   * @since 2.2.0
+   */
+  def createOrReplaceGlobalTempView(viewName: String): Unit = withPlan {
+    createTempViewCommand(viewName, replace = true, global = true)
+  }
+
   private def createTempViewCommand(
       viewName: String,
       replace: Boolean,

sql/core/src/test/scala/org/apache/spark/sql/execution/GlobalTempViewSuite.scala

@@ -35,39 +35,47 @@ class GlobalTempViewSuite extends QueryTest with SharedSQLContext {
   private var globalTempDB: String = _
 
   test("basic semantic") {
-    sql("CREATE GLOBAL TEMP VIEW src AS SELECT 1, 'a'")
+    try {
+      sql("CREATE GLOBAL TEMP VIEW src AS SELECT 1, 'a'")
+
+      // If there is no database in table name, we should try local temp view first, if not found,
+      // try table/view in current database, which is "default" in this case. So we expect
+      // NoSuchTableException here.
+      intercept[NoSuchTableException](spark.table("src"))
 
-    // If there is no database in table name, we should try local temp view first, if not found,
-    // try table/view in current database, which is "default" in this case. So we expect
-    // NoSuchTableException here.
-    intercept[NoSuchTableException](spark.table("src"))
+      // Use qualified name to refer to the global temp view explicitly.
+      checkAnswer(spark.table(s"$globalTempDB.src"), Row(1, "a"))
 
-    // Use qualified name to refer to the global temp view explicitly.
-    checkAnswer(spark.table(s"$globalTempDB.src"), Row(1, "a"))
+      // Table name without database will never refer to a global temp view.
+      intercept[NoSuchTableException](sql("DROP VIEW src"))
 
-    // Table name without database will never refer to a global temp view.
-    intercept[NoSuchTableException](sql("DROP VIEW src"))
+      sql(s"DROP VIEW $globalTempDB.src")
+      // The global temp view should be dropped successfully.
+      intercept[NoSuchTableException](spark.table(s"$globalTempDB.src"))
 
-    sql(s"DROP VIEW $globalTempDB.src")
-    // The global temp view should be dropped successfully.
-    intercept[NoSuchTableException](spark.table(s"$globalTempDB.src"))
+      // We can also use Dataset API to create global temp view
+      Seq(1 -> "a").toDF("i", "j").createGlobalTempView("src")
+      checkAnswer(spark.table(s"$globalTempDB.src"), Row(1, "a"))
 
-    // We can also use Dataset API to create global temp view
-    Seq(1 -> "a").toDF("i", "j").createGlobalTempView("src")
-    checkAnswer(spark.table(s"$globalTempDB.src"), Row(1, "a"))
+      // Use qualified name to rename a global temp view.
+      sql(s"ALTER VIEW $globalTempDB.src RENAME TO src2")
+      intercept[NoSuchTableException](spark.table(s"$globalTempDB.src"))
+      checkAnswer(spark.table(s"$globalTempDB.src2"), Row(1, "a"))
 
-    // Use qualified name to rename a global temp view.
-    sql(s"ALTER VIEW $globalTempDB.src RENAME TO src2")
-    intercept[NoSuchTableException](spark.table(s"$globalTempDB.src"))
-    checkAnswer(spark.table(s"$globalTempDB.src2"), Row(1, "a"))
+      // Use qualified name to alter a global temp view.
+      sql(s"ALTER VIEW $globalTempDB.src2 AS SELECT 2, 'b'")
+      checkAnswer(spark.table(s"$globalTempDB.src2"), Row(2, "b"))
 
-    // Use qualified name to alter a global temp view.
-    sql(s"ALTER VIEW $globalTempDB.src2 AS SELECT 2, 'b'")
-    checkAnswer(spark.table(s"$globalTempDB.src2"), Row(2, "b"))
+      // We can also use Catalog API to drop global temp view
+      spark.catalog.dropGlobalTempView("src2")
+      intercept[NoSuchTableException](spark.table(s"$globalTempDB.src2"))
 
-    // We can also use Catalog API to drop global temp view
-    spark.catalog.dropGlobalTempView("src2")
-    intercept[NoSuchTableException](spark.table(s"$globalTempDB.src2"))
+      // We can also use Dataset API to replace global temp view
+      Seq(2 -> "b").toDF("i", "j").createOrReplaceGlobalTempView("src")
+      checkAnswer(spark.table(s"$globalTempDB.src"), Row(2, "b"))
+    } finally {
+      spark.catalog.dropGlobalTempView("src")
+    }
   }
 
   test("global temp view is shared among all sessions") {
@@ -106,7 +114,7 @@ class GlobalTempViewSuite extends QueryTest with SharedSQLContext {
   test("CREATE TABLE LIKE should work for global temp view") {
     try {
       sql("CREATE GLOBAL TEMP VIEW src AS SELECT 1 AS a, '2' AS b")
-      sql(s"CREATE TABLE cloned LIKE ${globalTempDB}.src")
+      sql(s"CREATE TABLE cloned LIKE $globalTempDB.src")
       val tableMeta = spark.sessionState.catalog.getTableMetadata(TableIdentifier("cloned"))
       assert(tableMeta.schema == new StructType().add("a", "int", false).add("b", "string", false))
     } finally {