[SPARK-5002][SQL] Using ascending by default when not specify order in order by

spark sql does not support ```SELECT a, b FROM testData2 ORDER BY a desc, b```.

Author: wangfei <wangfei1@huawei.com>

Closes #3838 from scwf/orderby and squashes the following commits:

114b64a [wangfei] remove nouse methods
48145d3 [wangfei] fix order, using asc by default

1 files changed, 7 insertions, 0 deletions

diff --git a/sql/core/src/test/scala/org/apache/spark/sql/SQLQuerySuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/SQLQuerySuite.scala
index ddf4776ecf..add4e218a2 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/SQLQuerySuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/SQLQuerySuite.scala
@@ -987,6 +987,13 @@ class SQLQuerySuite extends QueryTest with BeforeAndAfterAll {
     )
   }
 
+  test("oder by asc by default when not specify ascending and descending") {
+    checkAnswer(
+      sql("SELECT a, b FROM testData2 ORDER BY a desc, b"),
+      Seq((3, 1), (3, 2), (2, 1), (2,2), (1, 1), (1, 2))
+    )
+  }
+
   test("Supporting relational operator '<=>' in Spark SQL") {
     val nullCheckData1 = TestData(1,"1") :: TestData(2,null) :: Nil
     val rdd1 = sparkContext.parallelize((0 to 1).map(i => nullCheckData1(i)))