SQLQuerySuite

Author: YanjieGao

sql/core/src/test/scala/org/apache/spark/sql/SQLQuerySuite.scala

@@ -369,6 +369,17 @@ class SQLQuerySuite extends QueryTest {
         (3, null)))
   }
 
+ test("subtract") {
+    checkAnswer(
+      sql("SELECT * FROM lowerCaseData SUBTRACT SELECT * FROM upperCaseData "),
+      (1, "a") ::
+              (2, "b") ::
+              (3, "c") ::
+              (4, "d") :: Nil)
+    checkAnswer(
+      sql("SELECT * FROM lowerCaseData SUBTRACT SELECT * FROM lowerCaseData "), Nil)
+  }
+  
   test("SET commands semantics using sql()") {
     clear()
     val testKey = "test.key.0"