2 files changed, 22 insertions, 1 deletions
diff --git a/sql/hive/src/main/antlr3/org/apache/spark/sql/parser/IdentifiersParser.g b/sql/hive/src/main/antlr3/org/apache/spark/sql/parser/IdentifiersParser.g
index 5c3d7ef866..9f1e168374 100644
--- a/sql/hive/src/main/antlr3/org/apache/spark/sql/parser/IdentifiersParser.g
+++ b/sql/hive/src/main/antlr3/org/apache/spark/sql/parser/IdentifiersParser.g
@@ -195,7 +195,7 @@ function
     RPAREN (KW_OVER ws=window_specification)?
            -> {$star != null}? ^(TOK_FUNCTIONSTAR functionName $ws?)
            -> {$dist == null}? ^(TOK_FUNCTION functionName (selectExpression+)? $ws?)
-                            -> ^(TOK_FUNCTIONDI functionName (selectExpression+)?)
+                            -> ^(TOK_FUNCTIONDI functionName (selectExpression+)? $ws?)
     ;
 
 functionName
diff --git a/sql/hive/src/test/scala/org/apache/spark/sql/hive/execution/SQLQuerySuite.scala b/sql/hive/src/test/scala/org/apache/spark/sql/hive/execution/SQLQuerySuite.scala
index bf65325d54..593fac2c32 100644
--- a/sql/hive/src/test/scala/org/apache/spark/sql/hive/execution/SQLQuerySuite.scala
+++ b/sql/hive/src/test/scala/org/apache/spark/sql/hive/execution/SQLQuerySuite.scala
@@ -915,6 +915,27 @@ class SQLQuerySuite extends QueryTest with SQLTestUtils with TestHiveSingleton {
       ).map(i => Row(i._1, i._2, i._3, i._4)))
   }
 
+  test("window function: distinct should not be silently ignored") {
+    val data = Seq(
+      WindowData(1, "a", 5),
+      WindowData(2, "a", 6),
+      WindowData(3, "b", 7),
+      WindowData(4, "b", 8),
+      WindowData(5, "c", 9),
+      WindowData(6, "c", 10)
+    )
+    sparkContext.parallelize(data).toDF().registerTempTable("windowData")
+
+    val e = intercept[AnalysisException] {
+      sql(
+        """
+          |select month, area, product, sum(distinct product + 1) over (partition by 1 order by 2)
+          |from windowData
+        """.stripMargin)
+    }
+    assert(e.getMessage.contains("Distinct window functions are not supported"))
+  }
+
   test("window function: expressions in arguments of a window functions") {
     val data = Seq(
       WindowData(1, "a", 5),