From 187aeb26df54daea4f38eb9a8605ee09985b55ae Mon Sep 17 00:00:00 2001
From: Andrei Zubkov <zubkov@moonset.ru>
Date: Wed, 22 Mar 2023 10:09:58 +0300
Subject: [PATCH 1/2] pg_stat_statements tests: Add NOT NULL checking of
 pg_stat_statements_reset

This is preliminary patch. It adds NOT NULL checking for the result of
pg_stat_statements_reset() function. It is needed for upcoming patch
"Track statement entry timestamp" that will change the result type of
this function to the timestamp of a reset performed.

Reviewed by: Julien Rouhaud, Hayato Kuroda, Yuki Seino, Chengxi Sun,
Anton Melnikov, Darren Rush, Michael Paquier, Sergei Kornilov

Discussion: https://www.postgresql.org/message-id/flat/72e80e7b160a6eb189df9ef6f068cce3765d37f8.camel%40moonset.ru
---
 .../pg_stat_statements/expected/cursors.out   |  28 ++--
 contrib/pg_stat_statements/expected/dml.out   |  20 +--
 .../expected/level_tracking.out               |  80 +++++-----
 .../pg_stat_statements/expected/planning.out  |  18 +--
 .../pg_stat_statements/expected/select.out    |  44 ++---
 .../expected/user_activity.out                | 120 +++++++-------
 .../pg_stat_statements/expected/utility.out   | 150 +++++++++---------
 contrib/pg_stat_statements/expected/wal.out   |  10 +-
 contrib/pg_stat_statements/sql/cursors.sql    |   6 +-
 contrib/pg_stat_statements/sql/dml.sql        |   4 +-
 .../pg_stat_statements/sql/level_tracking.sql |  12 +-
 contrib/pg_stat_statements/sql/planning.sql   |   4 +-
 contrib/pg_stat_statements/sql/select.sql     |  10 +-
 .../pg_stat_statements/sql/user_activity.sql  |  15 +-
 contrib/pg_stat_statements/sql/utility.sql    |  28 ++--
 contrib/pg_stat_statements/sql/wal.sql        |   2 +-
 16 files changed, 278 insertions(+), 273 deletions(-)

diff --git a/contrib/pg_stat_statements/expected/cursors.out b/contrib/pg_stat_statements/expected/cursors.out
index 46375ea9051..0fc4b2c098d 100644
--- a/contrib/pg_stat_statements/expected/cursors.out
+++ b/contrib/pg_stat_statements/expected/cursors.out
@@ -3,10 +3,10 @@
 --
 -- These tests require track_utility to be enabled.
 SET pg_stat_statements.track_utility = TRUE;
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- DECLARE
@@ -20,13 +20,13 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
 -------+------+-------------------------------------------------------
      2 |    0 | CLOSE cursor_stats_1
      2 |    0 | DECLARE cursor_stats_1 CURSOR WITH HOLD FOR SELECT $1
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (3 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- FETCH
@@ -59,12 +59,12 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      1 |    0 | DECLARE cursor_stats_2 CURSOR WITH HOLD FOR SELECT $1
      1 |    1 | FETCH 1 IN cursor_stats_1
      1 |    1 | FETCH 1 IN cursor_stats_2
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (9 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
diff --git a/contrib/pg_stat_statements/expected/dml.out b/contrib/pg_stat_statements/expected/dml.out
index 7b9c8f979ee..4c723a038b9 100644
--- a/contrib/pg_stat_statements/expected/dml.out
+++ b/contrib/pg_stat_statements/expected/dml.out
@@ -81,16 +81,16 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      1 |   12 | SELECT * FROM pgss_dml_tab ORDER BY a
      2 |    4 | SELECT * FROM pgss_dml_tab WHERE a > $1 ORDER BY a
      1 |    8 | SELECT * FROM pgss_dml_tab WHERE a IN ($1, $2, $3, $4, $5)
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
      1 |    0 | SET pg_stat_statements.track_utility = FALSE
      6 |    6 | UPDATE pgss_dml_tab SET b = $1 WHERE a = $2
      1 |    3 | UPDATE pgss_dml_tab SET b = $1 WHERE a > $2
 (10 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- MERGE
@@ -136,12 +136,12 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
        |      |  WHEN NOT MATCHED THEN INSERT (a, b) VALUES ($1, $2)
      1 |    0 | MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a)               +
        |      |  WHEN NOT MATCHED THEN INSERT (b, a) VALUES ($1, $2)
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (10 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
diff --git a/contrib/pg_stat_statements/expected/level_tracking.out b/contrib/pg_stat_statements/expected/level_tracking.out
index d924c87b41e..bad20e7f176 100644
--- a/contrib/pg_stat_statements/expected/level_tracking.out
+++ b/contrib/pg_stat_statements/expected/level_tracking.out
@@ -2,10 +2,10 @@
 -- Statement level tracking
 --
 SET pg_stat_statements.track_utility = TRUE;
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- DO block - top-level tracking.
@@ -29,10 +29,10 @@ SELECT toplevel, calls, query FROM pg_stat_statements
           |       | $$ LANGUAGE plpgsql
 (2 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- DO block - all-level tracking.
@@ -49,31 +49,31 @@ BEGIN
 END; $$;
 SELECT toplevel, calls, query FROM pg_stat_statements
   ORDER BY query COLLATE "C", toplevel;
- toplevel | calls |                query                 
-----------+-------+--------------------------------------
+ toplevel | calls |                       query                        
+----------+-------+----------------------------------------------------
  f        |     1 | DELETE FROM stats_track_tab
  t        |     1 | DELETE FROM stats_track_tab
- t        |     1 | DO $$                               +
-          |       | BEGIN                               +
-          |       |   DELETE FROM stats_track_tab;      +
+ t        |     1 | DO $$                                             +
+          |       | BEGIN                                             +
+          |       |   DELETE FROM stats_track_tab;                    +
           |       | END; $$
- t        |     1 | DO LANGUAGE plpgsql $$              +
-          |       | BEGIN                               +
-          |       |   -- this is a SELECT               +
-          |       |   PERFORM 'hello world'::TEXT;      +
+ t        |     1 | DO LANGUAGE plpgsql $$                            +
+          |       | BEGIN                                             +
+          |       |   -- this is a SELECT                             +
+          |       |   PERFORM 'hello world'::TEXT;                    +
           |       | END; $$
  f        |     1 | SELECT $1::TEXT
- t        |     1 | SELECT pg_stat_statements_reset()
+ t        |     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
  t        |     1 | SET pg_stat_statements.track = 'all'
 (7 rows)
 
 -- PL/pgSQL function - top-level tracking.
 SET pg_stat_statements.track = 'top';
 SET pg_stat_statements.track_utility = FALSE;
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 CREATE FUNCTION PLUS_TWO(i INTEGER) RETURNS INTEGER AS $$
@@ -111,19 +111,19 @@ SELECT PLUS_ONE(10);
 (1 row)
 
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
- calls | rows |               query               
--------+------+-----------------------------------
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
      2 |    2 | SELECT PLUS_ONE($1)
      2 |    2 | SELECT PLUS_TWO($1)
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (3 rows)
 
 -- PL/pgSQL function - all-level tracking.
 SET pg_stat_statements.track = 'all';
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- we drop and recreate the functions to avoid any caching funnies
@@ -165,13 +165,13 @@ SELECT PLUS_ONE(1);
 (1 row)
 
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
- calls | rows |               query               
--------+------+-----------------------------------
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
      2 |    2 | SELECT (i + $2 + $3)::INTEGER
      2 |    2 | SELECT (i + $2)::INTEGER LIMIT $3
      2 |    2 | SELECT PLUS_ONE($1)
      2 |    2 | SELECT PLUS_TWO($1)
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (5 rows)
 
 DROP FUNCTION PLUS_ONE(INTEGER);
@@ -179,10 +179,10 @@ DROP FUNCTION PLUS_ONE(INTEGER);
 -- pg_stat_statements.track = none
 --
 SET pg_stat_statements.track = 'none';
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 SELECT 1 AS "one";
@@ -202,9 +202,9 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
 -------+------+-------
 (0 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
diff --git a/contrib/pg_stat_statements/expected/planning.out b/contrib/pg_stat_statements/expected/planning.out
index c3561dd7da3..9effd11fdc8 100644
--- a/contrib/pg_stat_statements/expected/planning.out
+++ b/contrib/pg_stat_statements/expected/planning.out
@@ -3,10 +3,10 @@
 --
 -- These tests require track_planning to be enabled.
 SET pg_stat_statements.track_planning = TRUE;
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 --
@@ -64,7 +64,7 @@ SELECT plans, calls, rows, query FROM pg_stat_statements
      0 |     1 |    0 | ALTER TABLE stats_plan_test ADD COLUMN x int
      0 |     1 |    0 | CREATE TABLE stats_plan_test ()
      3 |     3 |    3 | SELECT $1
-     0 |     1 |    1 | SELECT pg_stat_statements_reset()
+     0 |     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
      1 |     0 |    0 | SELECT plans, calls, rows, query FROM pg_stat_statements+
        |       |      |   WHERE query NOT LIKE $1 ORDER BY query COLLATE "C"
 (5 rows)
@@ -80,9 +80,9 @@ SELECT plans >= 2 AND plans <= calls AS plans_ok, calls, rows, query FROM pg_sta
 
 -- Cleanup
 DROP TABLE stats_plan_test;
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
diff --git a/contrib/pg_stat_statements/expected/select.out b/contrib/pg_stat_statements/expected/select.out
index 972539b2c51..dd6c756f67d 100644
--- a/contrib/pg_stat_statements/expected/select.out
+++ b/contrib/pg_stat_statements/expected/select.out
@@ -4,10 +4,10 @@
 CREATE EXTENSION pg_stat_statements;
 SET pg_stat_statements.track_utility = FALSE;
 SET pg_stat_statements.track_planning = TRUE;
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 --
@@ -138,7 +138,7 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      1 |    2 | SELECT $1 AS i UNION SELECT $2 ORDER BY i
      1 |    1 | SELECT $1 || $2
      0 |    0 | SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C"
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
      1 |    2 | WITH t(f) AS (                                                              +
        |      |   VALUES ($1), ($2)                                                         +
        |      | )                                                                           +
@@ -146,10 +146,10 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      1 |    1 | select $1::jsonb ? $2
 (12 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 --
@@ -157,10 +157,10 @@ SELECT pg_stat_statements_reset();
 --
 CREATE TABLE pgss_a (id integer PRIMARY KEY);
 CREATE TABLE pgss_b (id integer PRIMARY KEY, a_id integer REFERENCES pgss_a);
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- control query
@@ -236,17 +236,17 @@ SELECT calls, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      1 | SELECT * FROM pgss_a JOIN pgss_b ON pgss_b.a_id = pgss_a.id FOR UPDATE OF pgss_b, pgss_a
      1 | SELECT * FROM pgss_a JOIN pgss_b ON pgss_b.a_id = pgss_a.id FOR UPDATE SKIP LOCKED
      0 | SELECT calls, query FROM pg_stat_statements ORDER BY query COLLATE "C"
-     1 | SELECT pg_stat_statements_reset()
+     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (12 rows)
 
 DROP TABLE pgss_a, pgss_b CASCADE;
 --
 -- access to pg_stat_statements_info view
 --
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 SELECT dealloc FROM pg_stat_statements_info;
@@ -406,9 +406,9 @@ SELECT COUNT(*) FROM pg_stat_statements WHERE query LIKE '%SELECT GROUPING%';
      2
 (1 row)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
diff --git a/contrib/pg_stat_statements/expected/user_activity.out b/contrib/pg_stat_statements/expected/user_activity.out
index f3c6b6ab326..38faf18c7c5 100644
--- a/contrib/pg_stat_statements/expected/user_activity.out
+++ b/contrib/pg_stat_statements/expected/user_activity.out
@@ -2,10 +2,10 @@
 -- Track user activity and reset them
 --
 SET pg_stat_statements.track_utility = TRUE;
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 CREATE ROLE regress_stats_user1;
@@ -39,27 +39,27 @@ SELECT 1+1 AS "TWO";
 
 RESET ROLE;
 SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
-               query               | calls | rows 
------------------------------------+-------+------
- CREATE ROLE regress_stats_user1   |     1 |    0
- CREATE ROLE regress_stats_user2   |     1 |    0
- RESET ROLE                        |     2 |    0
- SELECT $1 AS "ONE"                |     1 |    1
- SELECT $1 AS "ONE"                |     1 |    1
- SELECT $1+$2 AS "TWO"             |     1 |    1
- SELECT $1+$2 AS "TWO"             |     1 |    1
- SELECT pg_stat_statements_reset() |     1 |    1
- SET ROLE regress_stats_user1      |     1 |    0
- SET ROLE regress_stats_user2      |     1 |    0
+                       query                        | calls | rows 
+----------------------------------------------------+-------+------
+ CREATE ROLE regress_stats_user1                    |     1 |    0
+ CREATE ROLE regress_stats_user2                    |     1 |    0
+ RESET ROLE                                         |     2 |    0
+ SELECT $1 AS "ONE"                                 |     1 |    1
+ SELECT $1 AS "ONE"                                 |     1 |    1
+ SELECT $1+$2 AS "TWO"                              |     1 |    1
+ SELECT $1+$2 AS "TWO"                              |     1 |    1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t |     1 |    1
+ SET ROLE regress_stats_user1                       |     1 |    0
+ SET ROLE regress_stats_user2                       |     1 |    0
 (10 rows)
 
 --
 -- Don't reset anything if any of the parameter is NULL
 --
-SELECT pg_stat_statements_reset(NULL);
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset(NULL) IS NOT NULL AS t;
+ t 
+---
+ f
 (1 row)
 
 SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
@@ -72,8 +72,8 @@ SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
  SELECT $1 AS "ONE"                                                           |     1 |    1
  SELECT $1+$2 AS "TWO"                                                        |     1 |    1
  SELECT $1+$2 AS "TWO"                                                        |     1 |    1
- SELECT pg_stat_statements_reset($1)                                          |     1 |    1
- SELECT pg_stat_statements_reset()                                            |     1 |    1
+ SELECT pg_stat_statements_reset($1) IS NOT NULL AS t                         |     1 |    1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                           |     1 |    1
  SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C" |     1 |   10
  SET ROLE regress_stats_user1                                                 |     1 |    0
  SET ROLE regress_stats_user2                                                 |     1 |    0
@@ -87,10 +87,11 @@ SELECT pg_stat_statements_reset(
 	(SELECT r.oid FROM pg_roles AS r WHERE r.rolname = 'regress_stats_user2'),
 	(SELECT d.oid FROM pg_database As d where datname = current_database()),
 	(SELECT s.queryid FROM pg_stat_statements AS s
-				WHERE s.query = 'SELECT $1+$2 AS "TWO"' LIMIT 1));
- pg_stat_statements_reset 
---------------------------
- 
+				WHERE s.query = 'SELECT $1+$2 AS "TWO"' LIMIT 1))
+	IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
@@ -106,9 +107,10 @@ SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
          (SELECT r.oid FROM pg_roles AS r WHERE r.rolname = $1),                 +|       | 
          (SELECT d.oid FROM pg_database As d where datname = current_database()),+|       | 
          (SELECT s.queryid FROM pg_stat_statements AS s                          +|       | 
-                                 WHERE s.query = $2 LIMIT $3))                    |       | 
- SELECT pg_stat_statements_reset($1)                                              |     1 |    1
- SELECT pg_stat_statements_reset()                                                |     1 |    1
+                                 WHERE s.query = $2 LIMIT $3))                   +|       | 
+         IS NOT NULL AS t                                                         |       | 
+ SELECT pg_stat_statements_reset($1) IS NOT NULL AS t                             |     1 |    1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                               |     1 |    1
  SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C"     |     2 |   22
  SET ROLE regress_stats_user1                                                     |     1 |    0
  SET ROLE regress_stats_user2                                                     |     1 |    0
@@ -117,12 +119,12 @@ SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
 --
 -- remove query ('SELECT $1 AS "ONE"') executed by two users
 --
-SELECT pg_stat_statements_reset(0,0,s.queryid)
+SELECT pg_stat_statements_reset(0,0,s.queryid) IS NOT NULL AS t
 	FROM pg_stat_statements AS s WHERE s.query = 'SELECT $1 AS "ONE"';
- pg_stat_statements_reset 
---------------------------
- 
- 
+ t 
+---
+ t
+ t
 (2 rows)
 
 SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
@@ -136,11 +138,12 @@ SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
          (SELECT r.oid FROM pg_roles AS r WHERE r.rolname = $1),                 +|       | 
          (SELECT d.oid FROM pg_database As d where datname = current_database()),+|       | 
          (SELECT s.queryid FROM pg_stat_statements AS s                          +|       | 
-                                 WHERE s.query = $2 LIMIT $3))                    |       | 
- SELECT pg_stat_statements_reset($1)                                              |     1 |    1
- SELECT pg_stat_statements_reset($1,$2,s.queryid)                                +|     1 |    2
+                                 WHERE s.query = $2 LIMIT $3))                   +|       | 
+         IS NOT NULL AS t                                                         |       | 
+ SELECT pg_stat_statements_reset($1) IS NOT NULL AS t                             |     1 |    1
+ SELECT pg_stat_statements_reset($1,$2,s.queryid) IS NOT NULL AS t               +|     1 |    2
          FROM pg_stat_statements AS s WHERE s.query = $3                          |       | 
- SELECT pg_stat_statements_reset()                                                |     1 |    1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                               |     1 |    1
  SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C"     |     3 |   34
  SET ROLE regress_stats_user1                                                     |     1 |    0
  SET ROLE regress_stats_user2                                                     |     1 |    0
@@ -149,11 +152,11 @@ SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
 --
 -- remove query of a user (regress_stats_user1)
 --
-SELECT pg_stat_statements_reset(r.oid)
+SELECT pg_stat_statements_reset(r.oid) IS NOT NULL AS t
 		FROM pg_roles AS r WHERE r.rolname = 'regress_stats_user1';
- pg_stat_statements_reset 
---------------------------
- 
+ t 
+---
+ t
 (1 row)
 
 SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
@@ -166,12 +169,13 @@ SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
          (SELECT r.oid FROM pg_roles AS r WHERE r.rolname = $1),                 +|       | 
          (SELECT d.oid FROM pg_database As d where datname = current_database()),+|       | 
          (SELECT s.queryid FROM pg_stat_statements AS s                          +|       | 
-                                 WHERE s.query = $2 LIMIT $3))                    |       | 
- SELECT pg_stat_statements_reset($1)                                              |     1 |    1
- SELECT pg_stat_statements_reset($1,$2,s.queryid)                                +|     1 |    2
+                                 WHERE s.query = $2 LIMIT $3))                   +|       | 
+         IS NOT NULL AS t                                                         |       | 
+ SELECT pg_stat_statements_reset($1) IS NOT NULL AS t                             |     1 |    1
+ SELECT pg_stat_statements_reset($1,$2,s.queryid) IS NOT NULL AS t               +|     1 |    2
          FROM pg_stat_statements AS s WHERE s.query = $3                          |       | 
- SELECT pg_stat_statements_reset()                                                |     1 |    1
- SELECT pg_stat_statements_reset(r.oid)                                          +|     1 |    1
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t                               |     1 |    1
+ SELECT pg_stat_statements_reset(r.oid) IS NOT NULL AS t                         +|     1 |    1
                  FROM pg_roles AS r WHERE r.rolname = $1                          |       | 
  SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C"     |     4 |   45
  SET ROLE regress_stats_user2                                                     |     1 |    0
@@ -180,16 +184,16 @@ SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
 --
 -- reset all
 --
-SELECT pg_stat_statements_reset(0,0,0);
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset(0,0,0) IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
-                 query                  | calls | rows 
-----------------------------------------+-------+------
- SELECT pg_stat_statements_reset(0,0,0) |     1 |    1
+                          query                          | calls | rows 
+---------------------------------------------------------+-------+------
+ SELECT pg_stat_statements_reset(0,0,0) IS NOT NULL AS t |     1 |    1
 (1 row)
 
 --
@@ -197,9 +201,9 @@ SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
 --
 DROP ROLE regress_stats_user1;
 DROP ROLE regress_stats_user2;
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
diff --git a/contrib/pg_stat_statements/expected/utility.out b/contrib/pg_stat_statements/expected/utility.out
index 0047aba5d1a..ccb0edd26cc 100644
--- a/contrib/pg_stat_statements/expected/utility.out
+++ b/contrib/pg_stat_statements/expected/utility.out
@@ -3,10 +3,10 @@
 --
 -- These tests require track_utility to be enabled.
 SET pg_stat_statements.track_utility = TRUE;
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- Tables, indexes, triggers
@@ -33,13 +33,13 @@ NOTICE:  table "tab_stats" does not exist, skipping
      1 |    0 | CREATE TEMP TABLE tab_stats (a int, b char(20))
      3 |    0 | DROP TABLE IF EXISTS tab_stats
      1 |    0 | DROP TABLE tab_stats
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (8 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- Partitions
@@ -142,13 +142,13 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      1 |    0 | DROP TABLE trigger_tab_stats
      1 |    0 | DROP TYPE stats_type
      1 |    0 | DROP VIEW view_stats
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (39 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- Transaction statements
@@ -188,13 +188,13 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      1 |    0 | BEGIN TRANSACTION NOT DEFERRABLE, READ ONLY, READ WRITE, DEFERRABLE
      1 |    0 | BEGIN TRANSACTION READ ONLY, READ WRITE, DEFERRABLE, NOT DEFERRABLE
      7 |    0 | COMMIT WORK
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (8 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- EXPLAIN statements
@@ -230,7 +230,7 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
 -------+------+---------------------------------------------------------------------------------
      2 |    0 | EXPLAIN (costs off) SELECT $1
      2 |    0 | EXPLAIN (costs off) SELECT a FROM generate_series($1,$2) AS tab(a) WHERE a = $3
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (3 rows)
 
 -- CALL
@@ -246,10 +246,10 @@ DECLARE
 BEGIN
   SELECT (i + j)::int INTO r;
 END; $$ LANGUAGE plpgsql;
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 CALL sum_one(3);
@@ -257,21 +257,21 @@ CALL sum_one(199);
 CALL sum_two(1,1);
 CALL sum_two(1,2);
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
- calls | rows |               query               
--------+------+-----------------------------------
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
      1 |    0 | CALL sum_one(199)
      1 |    0 | CALL sum_one(3)
      1 |    0 | CALL sum_two(1,1)
      1 |    0 | CALL sum_two(1,2)
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (5 rows)
 
 -- COPY
 CREATE TABLE copy_stats (a int, b int);
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- Some queries with A_Const nodes.
@@ -301,14 +301,14 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      1 |    1 | COPY (SELECT 2) TO STDOUT
      1 |    2 | COPY (UPDATE copy_stats SET b = b + 1 RETURNING *) TO STDOUT
      1 |    2 | COPY (UPDATE copy_stats SET b = b + 2 RETURNING *) TO STDOUT
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (8 rows)
 
 DROP TABLE copy_stats;
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- CREATE TABLE AS
@@ -334,13 +334,13 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
        |      |     FROM generate_series($2, $3) AS tab(a) WHERE a < $4 AND a > $5
      2 |    0 | DROP TABLE ctas_stats_1
      2 |    0 | DROP TABLE ctas_stats_2
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (5 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- CREATE MATERIALIZED VIEW
@@ -360,13 +360,13 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
        |      |   SELECT a AS col1, $1::int AS col2                               +
        |      |     FROM generate_series($2, $3) AS tab(a) WHERE a < $4 AND a > $5
      2 |    0 | DROP MATERIALIZED VIEW matview_stats_1
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (3 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- CREATE VIEW
@@ -388,13 +388,13 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
        |      |   SELECT a AS col1, 4::int AS col2                             +
        |      |     FROM generate_series(1, 5) AS tab(a) WHERE a < 4 AND a > 3
      2 |    0 | DROP VIEW view_stats_1
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (4 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- Domains
@@ -409,13 +409,13 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      1 |    0 | ALTER DOMAIN domain_stats SET DEFAULT '3'
      1 |    0 | CREATE DOMAIN domain_stats AS int CHECK (VALUE > 0)
      1 |    0 | DROP DOMAIN domain_stats
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (5 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- SET statements.
@@ -441,14 +441,14 @@ SET LOCAL SESSION AUTHORIZATION DEFAULT;
 RESET SESSION AUTHORIZATION;
 COMMIT;
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
- calls | rows |                      query                      
--------+------+-------------------------------------------------
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
      2 |    0 | BEGIN
      2 |    0 | COMMIT
      2 |    0 | RESET SESSION AUTHORIZATION
      1 |    0 | RESET enable_seqscan
      1 |    0 | RESET work_mem
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
      1 |    0 | SET LOCAL SESSION AUTHORIZATION DEFAULT
      1 |    0 | SET SESSION SESSION AUTHORIZATION DEFAULT
      1 |    0 | SET TRANSACTION ISOLATION LEVEL READ COMMITTED
@@ -460,10 +460,10 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      1 |    0 | SET work_mem = '2MB'
 (15 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 --
@@ -521,16 +521,16 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      1 |    1 | FETCH NEXT pgss_cursor
      1 |   13 | REFRESH MATERIALIZED VIEW pgss_matv
      1 |   10 | SELECT generate_series($1, $2) c INTO pgss_select_into
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (12 rows)
 
 DROP MATERIALIZED VIEW pgss_matv;
 DROP TABLE pgss_ctas;
 DROP TABLE pgss_select_into;
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
 -- SET statements.
@@ -543,20 +543,20 @@ SET enable_seqscan = off;
 SET enable_seqscan = on;
 RESET enable_seqscan;
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
- calls | rows |               query               
--------+------+-----------------------------------
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
      1 |    0 | RESET enable_seqscan
      1 |    0 | RESET work_mem
-     1 |    1 | SELECT pg_stat_statements_reset()
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
      1 |    0 | SET enable_seqscan = off
      1 |    0 | SET enable_seqscan = on
      2 |    0 | SET work_mem = '1MB'
      1 |    0 | SET work_mem = '2MB'
 (7 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
diff --git a/contrib/pg_stat_statements/expected/wal.out b/contrib/pg_stat_statements/expected/wal.out
index 9896ba25363..34a2bf5b033 100644
--- a/contrib/pg_stat_statements/expected/wal.out
+++ b/contrib/pg_stat_statements/expected/wal.out
@@ -17,14 +17,14 @@ FROM pg_stat_statements ORDER BY query COLLATE "C";
 --------------------------------------------------------------+-------+------+---------------------+-----------------------+---------------------
  DELETE FROM pgss_wal_tab WHERE a > $1                        |     1 |    1 | t                   | t                     | t
  INSERT INTO pgss_wal_tab VALUES(generate_series($1, $2), $3) |     1 |   10 | t                   | t                     | t
- SELECT pg_stat_statements_reset()                            |     1 |    1 | f                   | f                     | f
+ SELECT pg_stat_statements_reset() IS NOT NULL AS t           |     1 |    1 | f                   | f                     | f
  SET pg_stat_statements.track_utility = FALSE                 |     1 |    0 | f                   | f                     | t
  UPDATE pgss_wal_tab SET b = $1 WHERE a > $2                  |     1 |    3 | t                   | t                     | t
 (5 rows)
 
-SELECT pg_stat_statements_reset();
- pg_stat_statements_reset 
---------------------------
- 
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
 (1 row)
 
diff --git a/contrib/pg_stat_statements/sql/cursors.sql b/contrib/pg_stat_statements/sql/cursors.sql
index cef6dc9e1b8..61738ac470e 100644
--- a/contrib/pg_stat_statements/sql/cursors.sql
+++ b/contrib/pg_stat_statements/sql/cursors.sql
@@ -4,7 +4,7 @@
 
 -- These tests require track_utility to be enabled.
 SET pg_stat_statements.track_utility = TRUE;
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- DECLARE
 -- SELECT is normalized.
@@ -14,7 +14,7 @@ DECLARE cursor_stats_1 CURSOR WITH HOLD FOR SELECT 2;
 CLOSE cursor_stats_1;
 
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- FETCH
 BEGIN;
@@ -27,4 +27,4 @@ CLOSE cursor_stats_2;
 COMMIT;
 
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
diff --git a/contrib/pg_stat_statements/sql/dml.sql b/contrib/pg_stat_statements/sql/dml.sql
index af2f9fcf73b..49d1b3a2701 100644
--- a/contrib/pg_stat_statements/sql/dml.sql
+++ b/contrib/pg_stat_statements/sql/dml.sql
@@ -46,7 +46,7 @@ SELECT * FROM pgss_dml_tab ORDER BY a;
 SELECT * FROM pgss_dml_tab WHERE a IN (1, 2, 3, 4, 5);
 
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- MERGE
 MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a AND st.a >= 4)
@@ -73,4 +73,4 @@ MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a AND st.a
 DROP TABLE pgss_dml_tab;
 
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
diff --git a/contrib/pg_stat_statements/sql/level_tracking.sql b/contrib/pg_stat_statements/sql/level_tracking.sql
index 0c20b8ce69b..f039110601a 100644
--- a/contrib/pg_stat_statements/sql/level_tracking.sql
+++ b/contrib/pg_stat_statements/sql/level_tracking.sql
@@ -3,7 +3,7 @@
 --
 
 SET pg_stat_statements.track_utility = TRUE;
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- DO block - top-level tracking.
 CREATE TABLE stats_track_tab (x int);
@@ -16,7 +16,7 @@ END;
 $$ LANGUAGE plpgsql;
 SELECT toplevel, calls, query FROM pg_stat_statements
   WHERE query LIKE '%DELETE%' ORDER BY query COLLATE "C", toplevel;
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- DO block - all-level tracking.
 SET pg_stat_statements.track = 'all';
@@ -36,7 +36,7 @@ SELECT toplevel, calls, query FROM pg_stat_statements
 -- PL/pgSQL function - top-level tracking.
 SET pg_stat_statements.track = 'top';
 SET pg_stat_statements.track_utility = FALSE;
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 CREATE FUNCTION PLUS_TWO(i INTEGER) RETURNS INTEGER AS $$
 DECLARE
   r INTEGER;
@@ -59,7 +59,7 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
 
 -- PL/pgSQL function - all-level tracking.
 SET pg_stat_statements.track = 'all';
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- we drop and recreate the functions to avoid any caching funnies
 DROP FUNCTION PLUS_ONE(INTEGER);
@@ -91,10 +91,10 @@ DROP FUNCTION PLUS_ONE(INTEGER);
 -- pg_stat_statements.track = none
 --
 SET pg_stat_statements.track = 'none';
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 SELECT 1 AS "one";
 SELECT 1 + 1 AS "two";
 
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
diff --git a/contrib/pg_stat_statements/sql/planning.sql b/contrib/pg_stat_statements/sql/planning.sql
index a59b9363c4b..46f5d9b951c 100644
--- a/contrib/pg_stat_statements/sql/planning.sql
+++ b/contrib/pg_stat_statements/sql/planning.sql
@@ -4,7 +4,7 @@
 
 -- These tests require track_planning to be enabled.
 SET pg_stat_statements.track_planning = TRUE;
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 --
 -- [re]plan counting
@@ -28,4 +28,4 @@ SELECT plans >= 2 AND plans <= calls AS plans_ok, calls, rows, query FROM pg_sta
 
 -- Cleanup
 DROP TABLE stats_plan_test;
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
diff --git a/contrib/pg_stat_statements/sql/select.sql b/contrib/pg_stat_statements/sql/select.sql
index eef7b0bbf58..eb45cb81ad2 100644
--- a/contrib/pg_stat_statements/sql/select.sql
+++ b/contrib/pg_stat_statements/sql/select.sql
@@ -5,7 +5,7 @@
 CREATE EXTENSION pg_stat_statements;
 SET pg_stat_statements.track_utility = FALSE;
 SET pg_stat_statements.track_planning = TRUE;
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 --
 -- simple and compound statements
@@ -56,7 +56,7 @@ EXECUTE pgss_test(1);
 DEALLOCATE pgss_test;
 
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 --
 -- queries with locking clauses
@@ -64,7 +64,7 @@ SELECT pg_stat_statements_reset();
 CREATE TABLE pgss_a (id integer PRIMARY KEY);
 CREATE TABLE pgss_b (id integer PRIMARY KEY, a_id integer REFERENCES pgss_a);
 
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- control query
 SELECT * FROM pgss_a JOIN pgss_b ON pgss_b.a_id = pgss_a.id;
@@ -92,7 +92,7 @@ DROP TABLE pgss_a, pgss_b CASCADE;
 --
 -- access to pg_stat_statements_info view
 --
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 SELECT dealloc FROM pg_stat_statements_info;
 
 -- FROM [ONLY]
@@ -146,4 +146,4 @@ SELECT (
 ) FROM (VALUES(6,7)) v3(e,f) GROUP BY ROLLUP(e,f);
 
 SELECT COUNT(*) FROM pg_stat_statements WHERE query LIKE '%SELECT GROUPING%';
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
diff --git a/contrib/pg_stat_statements/sql/user_activity.sql b/contrib/pg_stat_statements/sql/user_activity.sql
index 4b95edda890..07a5f36fc12 100644
--- a/contrib/pg_stat_statements/sql/user_activity.sql
+++ b/contrib/pg_stat_statements/sql/user_activity.sql
@@ -3,7 +3,7 @@
 --
 
 SET pg_stat_statements.track_utility = TRUE;
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 CREATE ROLE regress_stats_user1;
 CREATE ROLE regress_stats_user2;
 
@@ -24,7 +24,7 @@ SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
 --
 -- Don't reset anything if any of the parameter is NULL
 --
-SELECT pg_stat_statements_reset(NULL);
+SELECT pg_stat_statements_reset(NULL) IS NOT NULL AS t;
 SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
 
 --
@@ -35,27 +35,28 @@ SELECT pg_stat_statements_reset(
 	(SELECT r.oid FROM pg_roles AS r WHERE r.rolname = 'regress_stats_user2'),
 	(SELECT d.oid FROM pg_database As d where datname = current_database()),
 	(SELECT s.queryid FROM pg_stat_statements AS s
-				WHERE s.query = 'SELECT $1+$2 AS "TWO"' LIMIT 1));
+				WHERE s.query = 'SELECT $1+$2 AS "TWO"' LIMIT 1))
+	IS NOT NULL AS t;
 SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
 
 --
 -- remove query ('SELECT $1 AS "ONE"') executed by two users
 --
-SELECT pg_stat_statements_reset(0,0,s.queryid)
+SELECT pg_stat_statements_reset(0,0,s.queryid) IS NOT NULL AS t
 	FROM pg_stat_statements AS s WHERE s.query = 'SELECT $1 AS "ONE"';
 SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
 
 --
 -- remove query of a user (regress_stats_user1)
 --
-SELECT pg_stat_statements_reset(r.oid)
+SELECT pg_stat_statements_reset(r.oid) IS NOT NULL AS t
 		FROM pg_roles AS r WHERE r.rolname = 'regress_stats_user1';
 SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
 
 --
 -- reset all
 --
-SELECT pg_stat_statements_reset(0,0,0);
+SELECT pg_stat_statements_reset(0,0,0) IS NOT NULL AS t;
 SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
 
 --
@@ -63,4 +64,4 @@ SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
 --
 DROP ROLE regress_stats_user1;
 DROP ROLE regress_stats_user2;
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
diff --git a/contrib/pg_stat_statements/sql/utility.sql b/contrib/pg_stat_statements/sql/utility.sql
index 225d30a62a6..2d9b2684ebd 100644
--- a/contrib/pg_stat_statements/sql/utility.sql
+++ b/contrib/pg_stat_statements/sql/utility.sql
@@ -4,7 +4,7 @@
 
 -- These tests require track_utility to be enabled.
 SET pg_stat_statements.track_utility = TRUE;
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- Tables, indexes, triggers
 CREATE TEMP TABLE tab_stats (a int, b char(20));
@@ -18,7 +18,7 @@ DROP TABLE IF EXISTS tab_stats \;
 DROP TABLE IF EXISTS tab_stats \;
 Drop Table If Exists tab_stats \;
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- Partitions
 CREATE TABLE pt_stats (a int, b int) PARTITION BY range (a);
@@ -83,7 +83,7 @@ CREATE STATISTICS tab_expr_stats_1 (mcv) ON a, (2*a), (3*b) FROM tab_expr_stats;
 DROP TABLE tab_expr_stats;
 
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- Transaction statements
 BEGIN;
@@ -113,7 +113,7 @@ COMMIT;
 BEGIN TRANSACTION NOT DEFERRABLE, READ ONLY, READ WRITE, DEFERRABLE;
 COMMIT;
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- EXPLAIN statements
 -- A Query is used, normalized by the query jumbling.
@@ -137,7 +137,7 @@ DECLARE
 BEGIN
   SELECT (i + j)::int INTO r;
 END; $$ LANGUAGE plpgsql;
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 CALL sum_one(3);
 CALL sum_one(199);
 CALL sum_two(1,1);
@@ -146,7 +146,7 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
 
 -- COPY
 CREATE TABLE copy_stats (a int, b int);
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 -- Some queries with A_Const nodes.
 COPY (SELECT 1) TO STDOUT;
 COPY (SELECT 2) TO STDOUT;
@@ -158,7 +158,7 @@ COPY (DELETE FROM copy_stats WHERE a = 1 RETURNING *) TO STDOUT;
 
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
 DROP TABLE copy_stats;
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- CREATE TABLE AS
 -- SELECT queries are normalized, creating matching query IDs.
@@ -175,7 +175,7 @@ CREATE TABLE ctas_stats_2 AS
     FROM generate_series(1, 5) AS tab(a) WHERE a < 4 AND a > 1;
 DROP TABLE ctas_stats_2;
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- CREATE MATERIALIZED VIEW
 -- SELECT queries are normalized, creating matching query IDs.
@@ -188,7 +188,7 @@ CREATE MATERIALIZED VIEW matview_stats_1 AS
     FROM generate_series(1, 5) AS tab(a) WHERE a < 4 AND a > 3;
 DROP MATERIALIZED VIEW matview_stats_1;
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- CREATE VIEW
 CREATE VIEW view_stats_1 AS
@@ -200,7 +200,7 @@ CREATE VIEW view_stats_1 AS
     FROM generate_series(1, 5) AS tab(a) WHERE a < 4 AND a > 3;
 DROP VIEW view_stats_1;
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- Domains
 CREATE DOMAIN domain_stats AS int CHECK (VALUE > 0);
@@ -208,7 +208,7 @@ ALTER DOMAIN domain_stats SET DEFAULT '3';
 ALTER DOMAIN domain_stats ADD CONSTRAINT higher_than_one CHECK (VALUE > 1);
 DROP DOMAIN domain_stats;
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- SET statements.
 -- These use two different strings, still they count as one entry.
@@ -234,7 +234,7 @@ RESET SESSION AUTHORIZATION;
 COMMIT;
 
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 --
 -- Track the total number of rows retrieved or affected by the utility
@@ -263,7 +263,7 @@ DROP MATERIALIZED VIEW pgss_matv;
 DROP TABLE pgss_ctas;
 DROP TABLE pgss_select_into;
 
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
 
 -- SET statements.
 -- These use two different strings, still they count as one entry.
@@ -276,4 +276,4 @@ SET enable_seqscan = on;
 RESET enable_seqscan;
 
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
diff --git a/contrib/pg_stat_statements/sql/wal.sql b/contrib/pg_stat_statements/sql/wal.sql
index 34b21c0fa98..1dc1552a81e 100644
--- a/contrib/pg_stat_statements/sql/wal.sql
+++ b/contrib/pg_stat_statements/sql/wal.sql
@@ -17,4 +17,4 @@ wal_bytes > 0 as wal_bytes_generated,
 wal_records > 0 as wal_records_generated,
 wal_records >= rows as wal_records_ge_rows
 FROM pg_stat_statements ORDER BY query COLLATE "C";
-SELECT pg_stat_statements_reset();
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
-- 
2.30.2

