diff --git a/src/test/regress/expected/window.out b/src/test/regress/expected/window.out
index 0621bc089c3bd1525b31b7a77476de85d1656cb5..b6ebaadc811e578053ce56d158bea659edcc4c49 100644
--- a/src/test/regress/expected/window.out
+++ b/src/test/regress/expected/window.out
@@ -377,34 +377,34 @@ SELECT last_value(four) OVER (ORDER BY ten), ten, four FROM tenk1 WHERE unique2
 (10 rows)
 
 set search_path=singleseg, public;
-SELECT last_value(ten) OVER (PARTITION BY four), ten, four FROM
+SELECT last_value(ten) OVER (PARTITION BY four ORDER BY ten), ten, four FROM
 	(SELECT * FROM tenk1 WHERE unique2 < 10 ORDER BY four, ten)s
 	ORDER BY four, ten;
  last_value | ten | four 
 ------------+-----+------
           0 |   0 |    0
           0 |   0 |    0
-          0 |   4 |    0
+          4 |   4 |    0
           1 |   1 |    1
           1 |   1 |    1
-          1 |   7 |    1
-          1 |   9 |    1
+          7 |   7 |    1
+          9 |   9 |    1
           0 |   0 |    2
-          3 |   1 |    3
+          1 |   1 |    3
           3 |   3 |    3
 (10 rows)
 
-SELECT nth_value(ten, four + 1) OVER (PARTITION BY four), ten, four
+SELECT nth_value(ten, four + 1) OVER (PARTITION BY four ORDER BY ten), ten, four
 	FROM (SELECT * FROM tenk1 WHERE unique2 < 10 ORDER BY four, ten)s order by four,ten;
  nth_value | ten | four 
 -----------+-----+------
          0 |   0 |    0
          0 |   0 |    0
          0 |   4 |    0
-         7 |   1 |    1
-         7 |   1 |    1
-         7 |   7 |    1
-         7 |   9 |    1
+         1 |   1 |    1
+         1 |   1 |    1
+         1 |   7 |    1
+         1 |   9 |    1
            |   0 |    2
            |   1 |    3
            |   3 |    3
diff --git a/src/test/regress/sql/window.sql b/src/test/regress/sql/window.sql
index 7972aed24755d6e49d9b0f7d2358c4691300026f..487720bdbfb6540610ce47af4d9bb852031c2875 100644
--- a/src/test/regress/sql/window.sql
+++ b/src/test/regress/sql/window.sql
@@ -1,7 +1,3 @@
--- start_ignore
--- GPDB_84_MERGE_FIXME
-set optimizer to off;
--- end_ignore
 --
 -- WINDOW FUNCTIONS
 --
@@ -80,11 +76,11 @@ SELECT first_value(ten) OVER (PARTITION BY four ORDER BY ten), ten, four FROM te
 SELECT last_value(four) OVER (ORDER BY ten), ten, four FROM tenk1 WHERE unique2 < 10; 
 
 set search_path=singleseg, public;
-SELECT last_value(ten) OVER (PARTITION BY four), ten, four FROM
+SELECT last_value(ten) OVER (PARTITION BY four ORDER BY ten), ten, four FROM
 	(SELECT * FROM tenk1 WHERE unique2 < 10 ORDER BY four, ten)s
 	ORDER BY four, ten;
 
-SELECT nth_value(ten, four + 1) OVER (PARTITION BY four), ten, four
+SELECT nth_value(ten, four + 1) OVER (PARTITION BY four ORDER BY ten), ten, four
 	FROM (SELECT * FROM tenk1 WHERE unique2 < 10 ORDER BY four, ten)s order by four,ten;
 
 reset search_path;