[NSE-384] "Select count(*)" without group by results in error: java.l…

…ang.IllegalArgumentException: not all nodes and buffers were consumed (#385)

Closes #384

arrow-data-source/standard/src/test/scala/com/intel/oap/spark/sql/execution/datasources/arrow/ArrowDataSourceTest.scala

@@ -190,7 +190,7 @@ class ArrowDataSourceTest extends QueryTest with SharedSparkSession {
     frame2.createOrReplaceTempView("ptab2")
     val sqlFrame2 = spark.sql("select * from ptab2")
 
-    verifyFrame(sqlFrame2, 3, 1)
+    verifyFrame(sqlFrame2, 3, 2)
   }
 
   test("simple SQL query on parquet file with pushed filters") {
@@ -243,6 +243,17 @@ class ArrowDataSourceTest extends QueryTest with SharedSparkSession {
     }
   }
 
+  test("count(*) without group by v2") {
+    val path = ArrowDataSourceTest.locateResourcePath(parquetFile1)
+    val frame = spark.read
+        .option(ArrowOptions.KEY_ORIGINAL_FORMAT, "parquet")
+        .arrow(path)
+    frame.createOrReplaceTempView("ptab")
+    val df = sql("SELECT COUNT(*) FROM ptab")
+    checkAnswer(df, Row(5) :: Nil)
+
+  }
+
   test("file descriptor leak") {
     val path = ArrowDataSourceTest.locateResourcePath(parquetFile1)
     val frame = spark.read

native-sql-engine/core/src/test/scala/com/intel/oap/tpc/ds/TPCDSSuite.scala

@@ -145,6 +145,13 @@ class TPCDSSuite extends QueryTest with SharedSparkSession {
     df.explain()
     df.show()
   }
+
+  test("count() without group by") {
+    val df = spark.sql("SELECT count(*) as cnt FROM " +
+        "item LIMIT 100")
+    df.explain()
+    df.show()
+  }
 }
 
 object TPCDSSuite {