Revert support for improved tracking of nested queries

This commit reverts the two following commits:
- 499edb09741b, track more precisely query locations for nested
statements.
- 06450c7b8c70, a follow-up fix of 499edb09741b with query locations.
The test introduced in this commit is not reverted.  This is proving
useful to track a problem that only pgaudit was able to detect.

These prove to have issues with the tracking of SELECT statements, when
these use multiple parenthesis which is something supported by the
grammar.  Incorrect location and lengths are causing pg_stat_statements
to become confused, failing its job in query normalization with
potential out-of-bound writes because the location and the length may
not match with what can be handled.  A lot of the query patterns
discussed when this issue was reported have no test coverage in the main
regression test suite, or the recovery test 027_stream_regress.pl would
have caught the problems as pg_stat_statements is loaded by the node
running the regression tests.  A first step would be to improve the test
coverage to stress more the query normalization logic.

A different portion of this work was done in 45e0ba30fc40, with the
addition of tests for nested queries.  These can be left in the tree.
They are useful to track the way inner queries are currently tracked by
PGSS with non-top-level entries, and will be useful when reconsidering
in the future the work reverted here.

Reported-by: Alexander Kozhemyakin <a.kozhemyakin@postgrespro.ru>
Discussion: https://postgr.es/m/18947-cdd2668beffe02bf@postgresql.org

6 files changed, 108 insertions, 104 deletions

diff --git a/contrib/pg_overexplain/expected/pg_overexplain.out b/contrib/pg_overexplain/expected/pg_overexplain.out
index cb5c396c519..6de02323d7c 100644
--- a/contrib/pg_overexplain/expected/pg_overexplain.out
+++ b/contrib/pg_overexplain/expected/pg_overexplain.out
@@ -37,7 +37,7 @@ EXPLAIN (DEBUG) SELECT 1;
    Subplans Needing Rewind: none
    Relation OIDs: none
    Executor Parameter Types: none
-   Parse Location: 16 for 8 bytes
+   Parse Location: 0 to end
 (11 rows)
 
 EXPLAIN (RANGE_TABLE) SELECT 1;
@@ -119,7 +119,7 @@ $$);
    Subplans Needing Rewind: none
    Relation OIDs: NNN...
    Executor Parameter Types: none
-   Parse Location: 41 to end
+   Parse Location: 0 to end
  RTI 1 (relation, inherited, in-from-clause):
    Eref: vegetables (id, name, genus)
    Relation: vegetables
@@ -240,7 +240,7 @@ $$);
        <Subplans-Needing-Rewind>none</Subplans-Needing-Rewind>      +
        <Relation-OIDs>NNN...</Relation-OIDs>                        +
        <Executor-Parameter-Types>none</Executor-Parameter-Types>    +
-       <Parse-Location>53 to end</Parse-Location>                   +
+       <Parse-Location>0 to end</Parse-Location>                    +
      </PlannedStmt>                                                 +
      <Range-Table>                                                  +
        <Range-Table-Entry>                                          +
@@ -344,7 +344,7 @@ $$);
    Subplans Needing Rewind: none
    Relation OIDs: NNN...
    Executor Parameter Types: none
-   Parse Location: 28 to end
+   Parse Location: 0 to end
 (37 rows)
 
 SET debug_parallel_query = false;
@@ -372,7 +372,7 @@ $$);
    Subplans Needing Rewind: none
    Relation OIDs: NNN...
    Executor Parameter Types: 0
-   Parse Location: 28 to end
+   Parse Location: 0 to end
 (15 rows)
 
 -- Create an index, and then attempt to force a nested loop with inner index
@@ -436,7 +436,7 @@ $$);
    Subplans Needing Rewind: none
    Relation OIDs: NNN...
    Executor Parameter Types: 23
-   Parse Location: 75 for 62 bytes
+   Parse Location: 0 to end
 (47 rows)
 
 RESET enable_hashjoin;
diff --git a/contrib/pg_stat_statements/expected/level_tracking.out b/contrib/pg_stat_statements/expected/level_tracking.out
index 75e785e1719..8213fcd2e61 100644
--- a/contrib/pg_stat_statements/expected/level_tracking.out
+++ b/contrib/pg_stat_statements/expected/level_tracking.out
@@ -206,37 +206,37 @@ EXPLAIN (COSTS OFF) SELECT 1 UNION SELECT 2;
 
 SELECT toplevel, calls, query FROM pg_stat_statements
   ORDER BY query COLLATE "C";
- toplevel | calls |                               query                                
-----------+-------+--------------------------------------------------------------------
- f        |     1 | DELETE FROM stats_track_tab
+ toplevel | calls |                                query                                
+----------+-------+---------------------------------------------------------------------
  t        |     1 | EXPLAIN (COSTS OFF) (SELECT $1, $2)
+ f        |     1 | EXPLAIN (COSTS OFF) (SELECT $1, $2);
  t        |     1 | EXPLAIN (COSTS OFF) (TABLE test_table)
+ f        |     1 | EXPLAIN (COSTS OFF) (TABLE test_table);
  t        |     1 | EXPLAIN (COSTS OFF) (VALUES ($1, $2))
+ f        |     1 | EXPLAIN (COSTS OFF) (VALUES ($1, $2));
  t        |     1 | EXPLAIN (COSTS OFF) DELETE FROM stats_track_tab
+ f        |     1 | EXPLAIN (COSTS OFF) DELETE FROM stats_track_tab;
  t        |     1 | EXPLAIN (COSTS OFF) INSERT INTO stats_track_tab VALUES (($1))
- t        |     1 | EXPLAIN (COSTS OFF) MERGE INTO stats_track_tab                    +
-          |       |   USING (SELECT id FROM generate_series($1, $2) id) ON x = id     +
-          |       |   WHEN MATCHED THEN UPDATE SET x = id                             +
+ f        |     1 | EXPLAIN (COSTS OFF) INSERT INTO stats_track_tab VALUES (($1));
+ t        |     1 | EXPLAIN (COSTS OFF) MERGE INTO stats_track_tab                     +
+          |       |   USING (SELECT id FROM generate_series($1, $2) id) ON x = id      +
+          |       |   WHEN MATCHED THEN UPDATE SET x = id                              +
           |       |   WHEN NOT MATCHED THEN INSERT (x) VALUES (id)
+ f        |     1 | EXPLAIN (COSTS OFF) MERGE INTO stats_track_tab                     +
+          |       |   USING (SELECT id FROM generate_series($1, $2) id) ON x = id      +
+          |       |   WHEN MATCHED THEN UPDATE SET x = id                              +
+          |       |   WHEN NOT MATCHED THEN INSERT (x) VALUES (id);
  t        |     1 | EXPLAIN (COSTS OFF) SELECT $1
  t        |     1 | EXPLAIN (COSTS OFF) SELECT $1 UNION SELECT $2
+ f        |     1 | EXPLAIN (COSTS OFF) SELECT $1 UNION SELECT $2;
+ f        |     1 | EXPLAIN (COSTS OFF) SELECT $1;
  t        |     1 | EXPLAIN (COSTS OFF) TABLE stats_track_tab
+ f        |     1 | EXPLAIN (COSTS OFF) TABLE stats_track_tab;
  t        |     1 | EXPLAIN (COSTS OFF) UPDATE stats_track_tab SET x = $1 WHERE x = $2
+ f        |     1 | EXPLAIN (COSTS OFF) UPDATE stats_track_tab SET x = $1 WHERE x = $2;
  t        |     1 | EXPLAIN (COSTS OFF) VALUES ($1)
- f        |     1 | INSERT INTO stats_track_tab VALUES (($1))
- f        |     1 | MERGE INTO stats_track_tab                                        +
-          |       |   USING (SELECT id FROM generate_series($1, $2) id) ON x = id     +
-          |       |   WHEN MATCHED THEN UPDATE SET x = id                             +
-          |       |   WHEN NOT MATCHED THEN INSERT (x) VALUES (id)
- f        |     1 | SELECT $1
- f        |     1 | SELECT $1 UNION SELECT $2
- f        |     1 | SELECT $1, $2
+ f        |     1 | EXPLAIN (COSTS OFF) VALUES ($1);
  t        |     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
- f        |     1 | TABLE stats_track_tab
- f        |     1 | TABLE test_table
- f        |     1 | UPDATE stats_track_tab SET x = $1 WHERE x = $2
- f        |     1 | VALUES ($1)
- f        |     1 | VALUES ($1, $2)
 (23 rows)
 
 -- EXPLAIN - top-level tracking.
@@ -405,20 +405,20 @@ EXPLAIN (COSTS OFF) SELECT 1, 2 UNION SELECT 3, 4\; EXPLAIN (COSTS OFF) (SELECT
 
 SELECT toplevel, calls, query FROM pg_stat_statements
   ORDER BY query COLLATE "C";
- toplevel | calls |                              query                              
-----------+-------+-----------------------------------------------------------------
- f        |     1 | (SELECT $1, $2, $3) UNION SELECT $4, $5, $6
+ toplevel | calls |                                                        query                                                        
+----------+-------+---------------------------------------------------------------------------------------------------------------------
  t        |     1 | EXPLAIN (COSTS OFF) (SELECT $1, $2, $3)
  t        |     1 | EXPLAIN (COSTS OFF) (SELECT $1, $2, $3) UNION SELECT $4, $5, $6
+ f        |     1 | EXPLAIN (COSTS OFF) (SELECT $1, $2, $3); EXPLAIN (COSTS OFF) (SELECT 1, 2, 3, 4);
  t        |     1 | EXPLAIN (COSTS OFF) (SELECT $1, $2, $3, $4)
+ f        |     1 | EXPLAIN (COSTS OFF) (SELECT 1, 2, 3); EXPLAIN (COSTS OFF) (SELECT $1, $2, $3, $4);
  t        |     1 | EXPLAIN (COSTS OFF) SELECT $1
  t        |     1 | EXPLAIN (COSTS OFF) SELECT $1, $2
  t        |     1 | EXPLAIN (COSTS OFF) SELECT $1, $2 UNION SELECT $3, $4
- f        |     1 | SELECT $1
- f        |     1 | SELECT $1, $2
- f        |     1 | SELECT $1, $2 UNION SELECT $3, $4
- f        |     1 | SELECT $1, $2, $3
- f        |     1 | SELECT $1, $2, $3, $4
+ f        |     1 | EXPLAIN (COSTS OFF) SELECT $1, $2 UNION SELECT $3, $4; EXPLAIN (COSTS OFF) (SELECT 1, 2, 3) UNION SELECT 3, 4, 5;
+ f        |     1 | EXPLAIN (COSTS OFF) SELECT $1; EXPLAIN (COSTS OFF) SELECT 1, 2;
+ f        |     1 | EXPLAIN (COSTS OFF) SELECT 1, 2 UNION SELECT 3, 4; EXPLAIN (COSTS OFF) (SELECT $1, $2, $3) UNION SELECT $4, $5, $6;
+ f        |     1 | EXPLAIN (COSTS OFF) SELECT 1; EXPLAIN (COSTS OFF) SELECT $1, $2;
  t        |     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (13 rows)
 
@@ -494,29 +494,29 @@ EXPLAIN (COSTS OFF) INSERT INTO stats_track_tab VALUES ((1))\; EXPLAIN (COSTS OF
 
 SELECT toplevel, calls, query FROM pg_stat_statements
   ORDER BY query COLLATE "C";
- toplevel | calls |                               query                                
-----------+-------+--------------------------------------------------------------------
- f        |     1 | DELETE FROM stats_track_tab
- f        |     1 | DELETE FROM stats_track_tab WHERE x = $1
+ toplevel | calls |                                                              query                                                               
+----------+-------+----------------------------------------------------------------------------------------------------------------------------------
  t        |     1 | EXPLAIN (COSTS OFF) (TABLE test_table)
  t        |     1 | EXPLAIN (COSTS OFF) (VALUES ($1, $2))
  t        |     1 | EXPLAIN (COSTS OFF) DELETE FROM stats_track_tab
  t        |     1 | EXPLAIN (COSTS OFF) DELETE FROM stats_track_tab WHERE x = $1
+ f        |     1 | EXPLAIN (COSTS OFF) DELETE FROM stats_track_tab; EXPLAIN (COSTS OFF) DELETE FROM stats_track_tab WHERE x = $1;
+ f        |     1 | EXPLAIN (COSTS OFF) DELETE FROM stats_track_tab; EXPLAIN (COSTS OFF) DELETE FROM stats_track_tab WHERE x = 1;
  t        |     1 | EXPLAIN (COSTS OFF) INSERT INTO stats_track_tab VALUES ($1), ($2)
  t        |     1 | EXPLAIN (COSTS OFF) INSERT INTO stats_track_tab VALUES (($1))
+ f        |     1 | EXPLAIN (COSTS OFF) INSERT INTO stats_track_tab VALUES (($1)); EXPLAIN (COSTS OFF) INSERT INTO stats_track_tab VALUES (1), (2);
+ f        |     1 | EXPLAIN (COSTS OFF) INSERT INTO stats_track_tab VALUES ((1)); EXPLAIN (COSTS OFF) INSERT INTO stats_track_tab VALUES ($1), ($2);
  t        |     1 | EXPLAIN (COSTS OFF) TABLE stats_track_tab
+ f        |     1 | EXPLAIN (COSTS OFF) TABLE stats_track_tab; EXPLAIN (COSTS OFF) (TABLE test_table);
+ f        |     1 | EXPLAIN (COSTS OFF) TABLE stats_track_tab; EXPLAIN (COSTS OFF) (TABLE test_table);
  t        |     1 | EXPLAIN (COSTS OFF) UPDATE stats_track_tab SET x = $1
  t        |     1 | EXPLAIN (COSTS OFF) UPDATE stats_track_tab SET x = $1 WHERE x = $2
+ f        |     1 | EXPLAIN (COSTS OFF) UPDATE stats_track_tab SET x = $1 WHERE x = $2; EXPLAIN (COSTS OFF) UPDATE stats_track_tab SET x = 1;
+ f        |     1 | EXPLAIN (COSTS OFF) UPDATE stats_track_tab SET x = 1 WHERE x = 1; EXPLAIN (COSTS OFF) UPDATE stats_track_tab SET x = $1;
  t        |     1 | EXPLAIN (COSTS OFF) VALUES ($1)
- f        |     1 | INSERT INTO stats_track_tab VALUES ($1), ($2)
- f        |     1 | INSERT INTO stats_track_tab VALUES (($1))
+ f        |     1 | EXPLAIN (COSTS OFF) VALUES ($1); EXPLAIN (COSTS OFF) (VALUES (1, 2));
+ f        |     1 | EXPLAIN (COSTS OFF) VALUES (1); EXPLAIN (COSTS OFF) (VALUES ($1, $2));
  t        |     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
- f        |     1 | TABLE stats_track_tab
- f        |     1 | TABLE test_table
- f        |     1 | UPDATE stats_track_tab SET x = $1
- f        |     1 | UPDATE stats_track_tab SET x = $1 WHERE x = $2
- f        |     1 | VALUES ($1)
- f        |     1 | VALUES ($1, $2)
 (21 rows)
 
 SELECT pg_stat_statements_reset() IS NOT NULL AS t;
@@ -547,18 +547,21 @@ EXPLAIN (COSTS OFF) MERGE INTO stats_track_tab
 
 SELECT toplevel, calls, query FROM pg_stat_statements
   ORDER BY query COLLATE "C";
- toplevel | calls |                             query                             
-----------+-------+---------------------------------------------------------------
- t        |     1 | EXPLAIN (COSTS OFF) MERGE INTO stats_track_tab               +
-          |       |   USING (SELECT id FROM generate_series($1, $2) id) ON x = id+
-          |       |   WHEN MATCHED THEN UPDATE SET x = id                        +
+ toplevel | calls |                                             query                                              
+----------+-------+------------------------------------------------------------------------------------------------
+ t        |     1 | EXPLAIN (COSTS OFF) MERGE INTO stats_track_tab                                                +
+          |       |   USING (SELECT id FROM generate_series($1, $2) id) ON x = id                                 +
+          |       |   WHEN MATCHED THEN UPDATE SET x = id                                                         +
           |       |   WHEN NOT MATCHED THEN INSERT (x) VALUES (id)
+ f        |     1 | EXPLAIN (COSTS OFF) MERGE INTO stats_track_tab                                                +
+          |       |   USING (SELECT id FROM generate_series($1, $2) id) ON x = id                                 +
+          |       |   WHEN MATCHED THEN UPDATE SET x = id                                                         +
+          |       |   WHEN NOT MATCHED THEN INSERT (x) VALUES (id); EXPLAIN (COSTS OFF) SELECT 1, 2, 3, 4, 5;
+ f        |     1 | EXPLAIN (COSTS OFF) MERGE INTO stats_track_tab                                                +
+          |       |   USING (SELECT id FROM generate_series(1, 10) id) ON x = id                                  +
+          |       |   WHEN MATCHED THEN UPDATE SET x = id                                                         +
+          |       |   WHEN NOT MATCHED THEN INSERT (x) VALUES (id); EXPLAIN (COSTS OFF) SELECT $1, $2, $3, $4, $5;
  t        |     1 | EXPLAIN (COSTS OFF) SELECT $1, $2, $3, $4, $5
- f        |     1 | MERGE INTO stats_track_tab                                   +
-          |       |   USING (SELECT id FROM generate_series($1, $2) id) ON x = id+
-          |       |   WHEN MATCHED THEN UPDATE SET x = id                        +
-          |       |   WHEN NOT MATCHED THEN INSERT (x) VALUES (id)
- f        |     1 | SELECT $1, $2, $3, $4, $5
  t        |     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (5 rows)
 
@@ -786,29 +789,29 @@ EXPLAIN (COSTS OFF) WITH a AS (select 4) SELECT 1 UNION SELECT 2;
 
 SELECT toplevel, calls, query FROM pg_stat_statements
   ORDER BY query COLLATE "C";
- toplevel | calls |                                          query                                           
-----------+-------+------------------------------------------------------------------------------------------
+ toplevel | calls |                                           query                                           
+----------+-------+-------------------------------------------------------------------------------------------
  t        |     1 | EXPLAIN (COSTS OFF) (WITH a AS (SELECT $1) (SELECT $2, $3))
+ f        |     1 | EXPLAIN (COSTS OFF) (WITH a AS (SELECT $1) (SELECT $2, $3));
  t        |     1 | EXPLAIN (COSTS OFF) WITH a AS (SELECT $1) DELETE FROM stats_track_tab
+ f        |     1 | EXPLAIN (COSTS OFF) WITH a AS (SELECT $1) DELETE FROM stats_track_tab;
  t        |     1 | EXPLAIN (COSTS OFF) WITH a AS (SELECT $1) INSERT INTO stats_track_tab VALUES (($2))
- t        |     1 | EXPLAIN (COSTS OFF) WITH a AS (SELECT $1) MERGE INTO stats_track_tab                    +
-          |       |   USING (SELECT id FROM generate_series($2, $3) id) ON x = id                           +
-          |       |   WHEN MATCHED THEN UPDATE SET x = id                                                   +
+ f        |     1 | EXPLAIN (COSTS OFF) WITH a AS (SELECT $1) INSERT INTO stats_track_tab VALUES (($2));
+ t        |     1 | EXPLAIN (COSTS OFF) WITH a AS (SELECT $1) MERGE INTO stats_track_tab                     +
+          |       |   USING (SELECT id FROM generate_series($2, $3) id) ON x = id                            +
+          |       |   WHEN MATCHED THEN UPDATE SET x = id                                                    +
           |       |   WHEN NOT MATCHED THEN INSERT (x) VALUES (id)
+ f        |     1 | EXPLAIN (COSTS OFF) WITH a AS (SELECT $1) MERGE INTO stats_track_tab                     +
+          |       |   USING (SELECT id FROM generate_series($2, $3) id) ON x = id                            +
+          |       |   WHEN MATCHED THEN UPDATE SET x = id                                                    +
+          |       |   WHEN NOT MATCHED THEN INSERT (x) VALUES (id);
  t        |     1 | EXPLAIN (COSTS OFF) WITH a AS (SELECT $1) SELECT $2
+ f        |     1 | EXPLAIN (COSTS OFF) WITH a AS (SELECT $1) SELECT $2;
  t        |     1 | EXPLAIN (COSTS OFF) WITH a AS (SELECT $1) UPDATE stats_track_tab SET x = $2 WHERE x = $3
+ f        |     1 | EXPLAIN (COSTS OFF) WITH a AS (SELECT $1) UPDATE stats_track_tab SET x = $2 WHERE x = $3;
  t        |     1 | EXPLAIN (COSTS OFF) WITH a AS (select $1) SELECT $2 UNION SELECT $3
+ f        |     1 | EXPLAIN (COSTS OFF) WITH a AS (select $1) SELECT $2 UNION SELECT $3;
  t        |     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
- f        |     1 | WITH a AS (SELECT $1) (SELECT $2, $3)
- f        |     1 | WITH a AS (SELECT $1) DELETE FROM stats_track_tab
- f        |     1 | WITH a AS (SELECT $1) INSERT INTO stats_track_tab VALUES (($2))
- f        |     1 | WITH a AS (SELECT $1) MERGE INTO stats_track_tab                                        +
-          |       |   USING (SELECT id FROM generate_series($2, $3) id) ON x = id                           +
-          |       |   WHEN MATCHED THEN UPDATE SET x = id                                                   +
-          |       |   WHEN NOT MATCHED THEN INSERT (x) VALUES (id)
- f        |     1 | WITH a AS (SELECT $1) SELECT $2
- f        |     1 | WITH a AS (SELECT $1) UPDATE stats_track_tab SET x = $2 WHERE x = $3
- f        |     1 | WITH a AS (select $1) SELECT $2 UNION SELECT $3
 (15 rows)
 
 -- EXPLAIN with CTEs - top-level tracking
@@ -918,13 +921,14 @@ EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF)
 
 SELECT toplevel, calls, query FROM pg_stat_statements
   ORDER BY query COLLATE "C";
- toplevel | calls |                                    query                                     
-----------+-------+------------------------------------------------------------------------------
- t        |     1 | EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF)          +
+ toplevel | calls |                                     query                                     
+----------+-------+-------------------------------------------------------------------------------
+ t        |     1 | EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF)           +
           |       |   DECLARE foocur CURSOR FOR SELECT * FROM stats_track_tab
+ f        |     1 | EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF)           +
+          |       |   DECLARE foocur CURSOR FOR SELECT * FROM stats_track_tab;
  t        |     1 | EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF) SELECT $1
- f        |     1 | SELECT $1
- f        |     1 | SELECT * FROM stats_track_tab
+ f        |     1 | EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF) SELECT $1;
  t        |     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (5 rows)
 
@@ -1047,10 +1051,10 @@ SELECT toplevel, calls, query FROM pg_stat_statements
  toplevel | calls |                              query                              
 ----------+-------+-----------------------------------------------------------------
  t        |     1 | CREATE TEMPORARY TABLE pgss_ctas_1 AS SELECT $1
+ f        |     1 | CREATE TEMPORARY TABLE pgss_ctas_1 AS SELECT $1;
  t        |     1 | CREATE TEMPORARY TABLE pgss_ctas_2 AS EXECUTE test_prepare_pgss
- f        |     1 | SELECT $1
+ f        |     1 | PREPARE test_prepare_pgss AS select generate_series($1, $2)
  t        |     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
- f        |     1 | select generate_series($1, $2)
 (5 rows)
 
 -- CREATE TABLE AS, top-level tracking.
@@ -1088,10 +1092,10 @@ EXPLAIN (COSTS OFF) CREATE TEMPORARY TABLE pgss_explain_ctas AS SELECT 1;
 
 SELECT toplevel, calls, query FROM pg_stat_statements
   ORDER BY query COLLATE "C";
- toplevel | calls |                                   query                                   
-----------+-------+---------------------------------------------------------------------------
+ toplevel | calls |                                   query                                    
+----------+-------+----------------------------------------------------------------------------
  t        |     1 | EXPLAIN (COSTS OFF) CREATE TEMPORARY TABLE pgss_explain_ctas AS SELECT $1
- f        |     1 | SELECT $1
+ f        |     1 | EXPLAIN (COSTS OFF) CREATE TEMPORARY TABLE pgss_explain_ctas AS SELECT $1;
  t        |     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (3 rows)
 
@@ -1136,14 +1140,14 @@ CLOSE foocur;
 COMMIT;
 SELECT toplevel, calls, query FROM pg_stat_statements
   ORDER BY query COLLATE "C";
- toplevel | calls |                          query                          
-----------+-------+---------------------------------------------------------
+ toplevel | calls |                          query                           
+----------+-------+----------------------------------------------------------
  t        |     1 | BEGIN
  t        |     1 | CLOSE foocur
  t        |     1 | COMMIT
  t        |     1 | DECLARE FOOCUR CURSOR FOR SELECT * from stats_track_tab
+ f        |     1 | DECLARE FOOCUR CURSOR FOR SELECT * from stats_track_tab;
  t        |     1 | FETCH FORWARD 1 FROM foocur
- f        |     1 | SELECT * from stats_track_tab
  t        |     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (7 rows)
 
@@ -1203,25 +1207,25 @@ COPY (DELETE FROM stats_track_tab WHERE x = 2 RETURNING x) TO stdout;
 2
 SELECT toplevel, calls, query FROM pg_stat_statements
   ORDER BY query COLLATE "C";
- toplevel | calls |                                   query                                   
-----------+-------+---------------------------------------------------------------------------
+ toplevel | calls |                                    query                                    
+----------+-------+-----------------------------------------------------------------------------
+ f        |     1 | COPY (DELETE FROM stats_track_tab WHERE x = $1 RETURNING x) TO stdout
  t        |     1 | COPY (DELETE FROM stats_track_tab WHERE x = 2 RETURNING x) TO stdout
+ f        |     1 | COPY (INSERT INTO stats_track_tab (x) VALUES ($1) RETURNING x) TO stdout
  t        |     1 | COPY (INSERT INTO stats_track_tab (x) VALUES (1) RETURNING x) TO stdout
- t        |     1 | COPY (MERGE INTO stats_track_tab USING (SELECT 1 id) ON x = id           +
-          |       |   WHEN MATCHED THEN UPDATE SET x = id                                    +
+ f        |     1 | COPY (MERGE INTO stats_track_tab USING (SELECT $1 id) ON x = id            +
+          |       |   WHEN MATCHED THEN UPDATE SET x = id                                      +
           |       |   WHEN NOT MATCHED THEN INSERT (x) VALUES (id) RETURNING x) TO stdout
+ t        |     1 | COPY (MERGE INTO stats_track_tab USING (SELECT 1 id) ON x = id             +
+          |       |   WHEN MATCHED THEN UPDATE SET x = id                                      +
+          |       |   WHEN NOT MATCHED THEN INSERT (x) VALUES (id) RETURNING x) TO stdout
+ f        |     1 | COPY (SELECT $1 UNION SELECT $2) TO stdout
+ f        |     1 | COPY (SELECT $1) TO stdout
  t        |     1 | COPY (SELECT 1 UNION SELECT 2) TO stdout
  t        |     1 | COPY (SELECT 1) TO stdout
+ f        |     1 | COPY (UPDATE stats_track_tab SET x = $1 WHERE x = $2 RETURNING x) TO stdout
  t        |     1 | COPY (UPDATE stats_track_tab SET x = 2 WHERE x = 1 RETURNING x) TO stdout
- f        |     1 | DELETE FROM stats_track_tab WHERE x = $1 RETURNING x
- f        |     1 | INSERT INTO stats_track_tab (x) VALUES ($1) RETURNING x
- f        |     1 | MERGE INTO stats_track_tab USING (SELECT $1 id) ON x = id                +
-          |       |   WHEN MATCHED THEN UPDATE SET x = id                                    +
-          |       |   WHEN NOT MATCHED THEN INSERT (x) VALUES (id) RETURNING x
- f        |     1 | SELECT $1
- f        |     1 | SELECT $1 UNION SELECT $2
  t        |     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
- f        |     1 | UPDATE stats_track_tab SET x = $1 WHERE x = $2 RETURNING x
 (13 rows)
 
 -- COPY - top-level tracking.
diff --git a/contrib/pg_stat_statements/expected/planning.out b/contrib/pg_stat_statements/expected/planning.out
index 3ee1928cbe9..9effd11fdc8 100644
--- a/contrib/pg_stat_statements/expected/planning.out
+++ b/contrib/pg_stat_statements/expected/planning.out
@@ -58,7 +58,7 @@ SELECT 42;
 (1 row)
 
 SELECT plans, calls, rows, query FROM pg_stat_statements
-  WHERE query NOT LIKE 'SELECT COUNT%' ORDER BY query COLLATE "C";
+  WHERE query NOT LIKE 'PREPARE%' ORDER BY query COLLATE "C";
  plans | calls | rows |                          query                           
 -------+-------+------+----------------------------------------------------------
      0 |     1 |    0 | ALTER TABLE stats_plan_test ADD COLUMN x int
@@ -72,10 +72,10 @@ SELECT plans, calls, rows, query FROM pg_stat_statements
 -- for the prepared statement we expect at least one replan, but cache
 -- invalidations could force more
 SELECT plans >= 2 AND plans <= calls AS plans_ok, calls, rows, query FROM pg_stat_statements
-  WHERE query LIKE 'SELECT COUNT%' ORDER BY query COLLATE "C";
- plans_ok | calls | rows |                query                 
-----------+-------+------+--------------------------------------
- t        |     4 |    4 | SELECT COUNT(*) FROM stats_plan_test
+  WHERE query LIKE 'PREPARE%' ORDER BY query COLLATE "C";
+ plans_ok | calls | rows |                         query                         
+----------+-------+------+-------------------------------------------------------
+ t        |     4 |    4 | PREPARE prep1 AS SELECT COUNT(*) FROM stats_plan_test
 (1 row)
 
 -- Cleanup
diff --git a/contrib/pg_stat_statements/expected/select.out b/contrib/pg_stat_statements/expected/select.out
index 038ae110364..e87835085f5 100644
--- a/contrib/pg_stat_statements/expected/select.out
+++ b/contrib/pg_stat_statements/expected/select.out
@@ -208,6 +208,7 @@ DEALLOCATE pgss_test;
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
  calls | rows |                                    query                                     
 -------+------+------------------------------------------------------------------------------
+     1 |    1 | PREPARE pgss_test (int) AS SELECT $1, $2 LIMIT $3
      4 |    4 | SELECT $1                                                                   +
        |      |   -- but this one will appear                                               +
        |      |   AS "text"
@@ -221,7 +222,6 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      2 |    2 | SELECT $1 AS "int" ORDER BY 1
      1 |    2 | SELECT $1 AS i UNION SELECT $2 ORDER BY i
      1 |    1 | SELECT $1 || $2
-     1 |    1 | SELECT $1, $2 LIMIT $3
      2 |    2 | SELECT DISTINCT $1 AS "int"
      0 |    0 | SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C"
      1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
diff --git a/contrib/pg_stat_statements/expected/utility.out b/contrib/pg_stat_statements/expected/utility.out
index aa4f0f7e628..060d4416dd7 100644
--- a/contrib/pg_stat_statements/expected/utility.out
+++ b/contrib/pg_stat_statements/expected/utility.out
@@ -540,7 +540,7 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
 -------+------+----------------------------------------------------
      2 |    0 | DEALLOCATE $1
      2 |    0 | DEALLOCATE ALL
-     2 |    2 | SELECT $1 AS a
+     2 |    2 | PREPARE stat_select AS SELECT $1 AS a
      1 |    1 | SELECT $1 as a
      1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (5 rows)
diff --git a/contrib/pg_stat_statements/sql/planning.sql b/contrib/pg_stat_statements/sql/planning.sql
index 9cfe206b3b0..46f5d9b951c 100644
--- a/contrib/pg_stat_statements/sql/planning.sql
+++ b/contrib/pg_stat_statements/sql/planning.sql
@@ -20,11 +20,11 @@ SELECT 42;
 SELECT 42;
 SELECT 42;
 SELECT plans, calls, rows, query FROM pg_stat_statements
-  WHERE query NOT LIKE 'SELECT COUNT%' ORDER BY query COLLATE "C";
+  WHERE query NOT LIKE 'PREPARE%' ORDER BY query COLLATE "C";
 -- for the prepared statement we expect at least one replan, but cache
 -- invalidations could force more
 SELECT plans >= 2 AND plans <= calls AS plans_ok, calls, rows, query FROM pg_stat_statements
-  WHERE query LIKE 'SELECT COUNT%' ORDER BY query COLLATE "C";
+  WHERE query LIKE 'PREPARE%' ORDER BY query COLLATE "C";
 
 -- Cleanup
 DROP TABLE stats_plan_test;