Reflect normalization of query strings for utilities in pg_stat_statements

Applying normalization changes how the following query strings are
reflected in pg_stat_statements, by showing Const nodes with a
dollar-signed parameter as this is how such queries are structured
internally once parsed:
- DECLARE
- EXPLAIN
- CREATE MATERIALIZED VIEW
- CREATE TABLE AS

More normalization could be done in the future depending on the parts
where query jumbling is applied (like A_Const nodes?), the changes being
reflected in the regression tests in majority created in de2aca2.  This
just allows the basics to work for utility queries using Const nodes.

Reviewed-by: Bertrand Drouvot
Discussion: https://postgr.es/m/Y+MRdEq9W9XVa2AB@paquier.xyz

contrib/pg_stat_statements/expected/cursors.out

@@ -17,9 +17,9 @@ 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";
  calls | rows |                         query                         
--------+------+------------------------------------------------------
+-------+------+-------------------------------------------------------
      2 |    0 | CLOSE cursor_stats_1
-     2 |    0 | DECLARE cursor_stats_1 CURSOR WITH HOLD FOR SELECT 1
+     2 |    0 | DECLARE cursor_stats_1 CURSOR WITH HOLD FOR SELECT $1
      1 |    1 | SELECT pg_stat_statements_reset()
 (3 rows)
 
@@ -50,13 +50,13 @@ CLOSE cursor_stats_2;
 COMMIT;
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
  calls | rows |                         query                         
--------+------+------------------------------------------------------
+-------+------+-------------------------------------------------------
      1 |    0 | BEGIN
      1 |    0 | CLOSE cursor_stats_1
      1 |    0 | CLOSE cursor_stats_2
      1 |    0 | COMMIT
-     1 |    0 | DECLARE cursor_stats_1 CURSOR WITH HOLD FOR SELECT 2
-     1 |    0 | DECLARE cursor_stats_2 CURSOR WITH HOLD FOR SELECT 3
+     1 |    0 | DECLARE cursor_stats_1 CURSOR WITH HOLD FOR SELECT $1
+     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()

contrib/pg_stat_statements/expected/utility.out

@@ -227,9 +227,9 @@ EXPLAIN (costs off) SELECT a FROM generate_series(1,10) AS tab(a) WHERE a = 7;
 
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
  calls | rows |                                      query                                      
--------+------+-------------------------------------------------------------------------------
-     2 |    0 | EXPLAIN (costs off) SELECT 1
-     2 |    0 | EXPLAIN (costs off) SELECT a FROM generate_series(1,10) AS tab(a) WHERE a = 3
+-------+------+---------------------------------------------------------------------------------
+     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()
 (3 rows)
 
@@ -327,11 +327,11 @@ CREATE TABLE ctas_stats_2 AS
 DROP TABLE ctas_stats_2;
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
  calls | rows |                               query                                
--------+------+-----------------------------------------------------------------
-     2 |    2 | CREATE TABLE ctas_stats_1 AS SELECT 1 AS a
+-------+------+--------------------------------------------------------------------
+     2 |    2 | CREATE TABLE ctas_stats_1 AS SELECT $1 AS a
      2 |    4 | CREATE TABLE ctas_stats_2 AS                                      +
-       |      |   SELECT a AS col1, 2::int AS col2                             +
-       |      |     FROM generate_series(1, 10) AS tab(a) WHERE a < 5 AND a > 2
+       |      |   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 TABLE ctas_stats_1
      2 |    0 | DROP TABLE ctas_stats_2
      1 |    1 | SELECT pg_stat_statements_reset()
@@ -355,10 +355,10 @@ CREATE MATERIALIZED VIEW matview_stats_1 AS
 DROP MATERIALIZED VIEW matview_stats_1;
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
  calls | rows |                               query                                
--------+------+-----------------------------------------------------------------
+-------+------+--------------------------------------------------------------------
      2 |    2 | CREATE MATERIALIZED VIEW matview_stats_1 AS                       +
-       |      |   SELECT a AS col1, 2::int AS col2                             +
-       |      |     FROM generate_series(1, 10) AS tab(a) WHERE a < 5 AND a > 2
+       |      |   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()
 (3 rows)
@@ -509,18 +509,18 @@ FETCH FORWARD ALL pgss_cursor;
 COMMIT;
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
  calls | rows |                                  query                                  
--------+------+----------------------------------------------------------------------------
+-------+------+-------------------------------------------------------------------------
      1 |    0 | BEGIN
      1 |    0 | COMMIT
      1 |    3 | COPY pgss_ctas (a, b) FROM STDIN
      1 |   13 | CREATE MATERIALIZED VIEW pgss_matv AS SELECT * FROM pgss_ctas
-     1 |   10 | CREATE TABLE pgss_ctas AS SELECT a, 'ctas' b FROM generate_series(1, 10) a
+     1 |   10 | CREATE TABLE pgss_ctas AS SELECT a, $1 b FROM generate_series($2, $3) a
      1 |    0 | DECLARE pgss_cursor CURSOR FOR SELECT * FROM pgss_matv
      1 |    5 | FETCH FORWARD 5 pgss_cursor
      1 |    7 | FETCH FORWARD ALL pgss_cursor
      1 |    1 | FETCH NEXT pgss_cursor
      1 |   13 | REFRESH MATERIALIZED VIEW pgss_matv
-     1 |   10 | SELECT generate_series(1, 10) c INTO pgss_select_into
+     1 |   10 | SELECT generate_series($1, $2) c INTO pgss_select_into
      1 |    1 | SELECT pg_stat_statements_reset()
 (12 rows)
 

contrib/pg_stat_statements/pg_stat_statements.c

@@ -836,9 +836,11 @@ pgss_post_parse_analyze(ParseState *pstate, Query *query, JumbleState *jstate)
 	if (query->utilityStmt)
 	{
 		if (pgss_track_utility && !PGSS_HANDLED_UTILITY(query->utilityStmt))
+		{
 			query->queryId = UINT64CONST(0);
 			return;
 		}
+	}
 
 	/*
 	 * If query jumbling were able to identify any ignorable constants, we