set hive.vectorized.execution.enabled=false;
set hive.optimize.topnkey=true;

CREATE TABLE t_test_grouping_sets(
  a int,
  b int,
  c int
);

INSERT INTO t_test_grouping_sets VALUES
(NULL, NULL, NULL),
(5, 2, 3),
(10, 11, 12),
(NULL, NULL, NULL),
(NULL, NULL, NULL),
(6, 2, 1),
(7, 8, 4), (7, 8, 4), (7, 8, 4),
(5, 1, 2), (5, 1, 2), (5, 1, 2),
(NULL, NULL, NULL);

set hive.optimize.topnkey=true;
EXPLAIN
SELECT a, b FROM t_test_grouping_sets GROUP BY a,b GROUPING SETS ((a,b), (a), (b), ()) ORDER BY b NULLS FIRST, a LIMIT 7;
SELECT a, b FROM t_test_grouping_sets GROUP BY a,b GROUPING SETS ((a,b), (a), (b), ()) ORDER BY b NULLS FIRST, a LIMIT 7;

set hive.optimize.topnkey=false;
SELECT a, b FROM t_test_grouping_sets GROUP BY a,b GROUPING SETS ((a,b), (a), (b), ()) ORDER BY b NULLS FIRST, a LIMIT 7;

set hive.optimize.topnkey=true;
EXPLAIN
SELECT a, b FROM t_test_grouping_sets GROUP BY a,b GROUPING SETS ((a,b), (a), (b), ()) ORDER BY b NULLS LAST, a LIMIT 7;
SELECT a, b FROM t_test_grouping_sets GROUP BY a,b GROUPING SETS ((a,b), (a), (b), ()) ORDER BY b NULLS LAST, a LIMIT 7;

set hive.optimize.topnkey=false;
SELECT a, b FROM t_test_grouping_sets GROUP BY a,b GROUPING SETS ((a,b), (a), (b), ()) ORDER BY b NULLS LAST, a LIMIT 7;

set hive.optimize.topnkey=true;
EXPLAIN
SELECT a, b FROM t_test_grouping_sets GROUP BY a,b GROUPING SETS ((a,b), (a), (b), ()) ORDER BY a DESC, b ASC LIMIT 7;
SELECT a, b FROM t_test_grouping_sets GROUP BY a,b GROUPING SETS ((a,b), (a), (b), ()) ORDER BY a DESC, b ASC LIMIT 7;

set hive.optimize.topnkey=false;
SELECT a, b FROM t_test_grouping_sets GROUP BY a,b GROUPING SETS ((a,b), (a), (b), ()) ORDER BY a DESC, b ASC LIMIT 7;

set hive.optimize.topnkey=true;
EXPLAIN
SELECT a, b FROM t_test_grouping_sets GROUP BY a,b GROUPING SETS ((a,b), (a), (b), ()) ORDER BY a DESC NULLS FIRST, b ASC NULLS FIRST LIMIT 7;
SELECT a, b FROM t_test_grouping_sets GROUP BY a,b GROUPING SETS ((a,b), (a), (b), ()) ORDER BY a DESC NULLS FIRST, b ASC NULLS FIRST LIMIT 7;

set hive.optimize.topnkey=false;
SELECT a, b FROM t_test_grouping_sets GROUP BY a,b GROUPING SETS ((a,b), (a), (b), ()) ORDER BY a DESC NULLS FIRST, b ASC NULLS FIRST LIMIT 7;

DROP TABLE IF EXISTS t_test_grouping_sets;