0001-Fix-regression-with-statement-location-of-some-subqu.patch

From 74b484ee4b05b5ff7139bfc3ae1c194060a6dfaf Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Tue, 20 May 2025 12:53:35 +0900
Subject: [PATCH] Fix regression with statement location of some subqueries

Note the changes in the output of pg_overexplain, as the new locations
refer to the beginning of the argument passed to the function
explain_filter().

Blah.
---
 src/backend/parser/analyze.c                  | 20 +++----
 .../expected/pg_overexplain.out               |  8 +--
 .../expected/level_tracking.out               | 57 +++++++++++++++++++
 .../pg_stat_statements/sql/level_tracking.sql | 32 +++++++++++
 4 files changed, 102 insertions(+), 15 deletions(-)

diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c
index 1f4d6adda524..bc524f0754ae 100644
--- a/src/backend/parser/analyze.c
+++ b/src/backend/parser/analyze.c
@@ -260,13 +260,6 @@ setQueryLocationAndLength(ParseState *pstate, Query *qry, Node *parseTree)
 {
 	ParseLoc	stmt_len = 0;
 
-	/*
-	 * If there is no information about the top RawStmt's length, leave it at
-	 * 0 to use the whole string.
-	 */
-	if (pstate->p_stmt_len == 0)
-		return;
-
 	switch (nodeTag(parseTree))
 	{
 		case T_InsertStmt:
@@ -308,16 +301,21 @@ setQueryLocationAndLength(ParseState *pstate, Query *qry, Node *parseTree)
 		/* Statement's length is known, use it */
 		qry->stmt_len = stmt_len;
 	}
-	else
+	else if (pstate->p_stmt_len > 0)
 	{
 		/*
-		 * Compute the statement's length from the statement's location and
-		 * the RawStmt's length and location.
+		 * The top RawStmt's length is known, so calculate the statement's
+		 * length from the statement's location and the RawStmt's length and
+		 * location.
 		 */
 		qry->stmt_len = pstate->p_stmt_len - (qry->stmt_location - pstate->p_stmt_location);
 	}
 
-	/* The calculated statement length should be calculated as positive. */
+	/*
+	 * The calculated statement length should be calculated as positive.  It
+	 * may be possible that stmt_len is 0, in which case the full remaining
+	 * string is used.
+	 */
 	Assert(qry->stmt_len >= 0);
 }
 
diff --git a/contrib/pg_overexplain/expected/pg_overexplain.out b/contrib/pg_overexplain/expected/pg_overexplain.out
index 44120c388af5..cb5c396c5192 100644
--- a/contrib/pg_overexplain/expected/pg_overexplain.out
+++ b/contrib/pg_overexplain/expected/pg_overexplain.out
@@ -119,7 +119,7 @@ $$);
    Subplans Needing Rewind: none
    Relation OIDs: NNN...
    Executor Parameter Types: none
-   Parse Location: 0 to end
+   Parse Location: 41 to end
  RTI 1 (relation, inherited, in-from-clause):
    Eref: vegetables (id, name, genus)
    Relation: vegetables
@@ -240,7 +240,7 @@ $$);
        <Subplans-Needing-Rewind>none</Subplans-Needing-Rewind>      +
        <Relation-OIDs>NNN...</Relation-OIDs>                        +
        <Executor-Parameter-Types>none</Executor-Parameter-Types>    +
-       <Parse-Location>0 to end</Parse-Location>                    +
+       <Parse-Location>53 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: 0 to end
+   Parse Location: 28 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: 0 to end
+   Parse Location: 28 to end
 (15 rows)
 
 -- Create an index, and then attempt to force a nested loop with inner index
diff --git a/contrib/pg_stat_statements/expected/level_tracking.out b/contrib/pg_stat_statements/expected/level_tracking.out
index 03bea14d5da0..ee6dea3a9cd3 100644
--- a/contrib/pg_stat_statements/expected/level_tracking.out
+++ b/contrib/pg_stat_statements/expected/level_tracking.out
@@ -1319,6 +1319,63 @@ SELECT toplevel, calls, query FROM pg_stat_statements
  t        |     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (4 rows)
 
+-- DO block --- multiple inner queries with separators
+SET pg_stat_statements.track = 'all';
+SET pg_stat_statements.track_utility = TRUE;
+CREATE TABLE pgss_do_util_tab_1 (a int);
+CREATE TABLE pgss_do_util_tab_2 (a int);
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+DO $$
+DECLARE BEGIN
+  EXECUTE 'CREATE TABLE pgss_do_table (weird_name INT); DROP TABLE pgss_do_table';
+  EXECUTE 'SELECT a FROM pgss_do_util_tab_1; SELECT a FROM pgss_do_util_tab_2';
+END $$;
+DO $$
+DECLARE BEGIN
+END $$;
+SELECT toplevel, calls, rows, query FROM pg_stat_statements
+  WHERE toplevel IS FALSE
+  ORDER BY query COLLATE "C";
+ toplevel | calls | rows |                    query                    
+----------+-------+------+---------------------------------------------
+ f        |     1 |    0 | CREATE TABLE pgss_do_table (weird_name INT)
+ f        |     1 |    0 | DROP TABLE pgss_do_table
+ f        |     1 |    0 | SELECT a FROM pgss_do_util_tab_1
+ f        |     1 |    0 | SELECT a FROM pgss_do_util_tab_2
+(4 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Note the extra semicolon at the end of the query.
+DO $$
+DECLARE BEGIN
+  EXECUTE 'CREATE TABLE pgss_do_table (weird_name INT); DROP TABLE pgss_do_table;';
+  EXECUTE 'SELECT a FROM pgss_do_util_tab_1; SELECT a FROM pgss_do_util_tab_2;';
+END $$;
+DO $$
+DECLARE BEGIN
+END $$;
+SELECT toplevel, calls, rows, query FROM pg_stat_statements
+  WHERE toplevel IS FALSE
+  ORDER BY query COLLATE "C";
+ toplevel | calls | rows |                    query                    
+----------+-------+------+---------------------------------------------
+ f        |     1 |    0 | CREATE TABLE pgss_do_table (weird_name INT)
+ f        |     1 |    0 | DROP TABLE pgss_do_table
+ f        |     1 |    0 | SELECT a FROM pgss_do_util_tab_1
+ f        |     1 |    0 | SELECT a FROM pgss_do_util_tab_2
+(4 rows)
+
+DROP TABLE pgss_do_util_tab_1, pgss_do_util_tab_2;
 -- PL/pgSQL function - top-level tracking.
 SET pg_stat_statements.track = 'top';
 SET pg_stat_statements.track_utility = FALSE;
diff --git a/contrib/pg_stat_statements/sql/level_tracking.sql b/contrib/pg_stat_statements/sql/level_tracking.sql
index 6b81230f1869..553059816915 100644
--- a/contrib/pg_stat_statements/sql/level_tracking.sql
+++ b/contrib/pg_stat_statements/sql/level_tracking.sql
@@ -334,6 +334,38 @@ END; $$;
 SELECT toplevel, calls, query FROM pg_stat_statements
   ORDER BY query COLLATE "C", toplevel;
 
+-- DO block --- multiple inner queries with separators
+SET pg_stat_statements.track = 'all';
+SET pg_stat_statements.track_utility = TRUE;
+CREATE TABLE pgss_do_util_tab_1 (a int);
+CREATE TABLE pgss_do_util_tab_2 (a int);
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+DO $$
+DECLARE BEGIN
+  EXECUTE 'CREATE TABLE pgss_do_table (weird_name INT); DROP TABLE pgss_do_table';
+  EXECUTE 'SELECT a FROM pgss_do_util_tab_1; SELECT a FROM pgss_do_util_tab_2';
+END $$;
+DO $$
+DECLARE BEGIN
+END $$;
+SELECT toplevel, calls, rows, query FROM pg_stat_statements
+  WHERE toplevel IS FALSE
+  ORDER BY query COLLATE "C";
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+-- Note the extra semicolon at the end of the query.
+DO $$
+DECLARE BEGIN
+  EXECUTE 'CREATE TABLE pgss_do_table (weird_name INT); DROP TABLE pgss_do_table;';
+  EXECUTE 'SELECT a FROM pgss_do_util_tab_1; SELECT a FROM pgss_do_util_tab_2;';
+END $$;
+DO $$
+DECLARE BEGIN
+END $$;
+SELECT toplevel, calls, rows, query FROM pg_stat_statements
+  WHERE toplevel IS FALSE
+  ORDER BY query COLLATE "C";
+DROP TABLE pgss_do_util_tab_1, pgss_do_util_tab_2;
+
 -- PL/pgSQL function - top-level tracking.
 SET pg_stat_statements.track = 'top';
 SET pg_stat_statements.track_utility = FALSE;
-- 
2.49.0