postgresql/contrib/pg_stat_statements/sql/pg_stat_statements.sql
Magnus Hagander 6b4d23feef Track identical top vs nested queries independently in pg_stat_statements
Changing pg_stat_statements.track between 'all' and 'top' would control
if pg_stat_statements tracked just top level statements or also
statements inside functions, but when tracking all it would not
differentiate between the two. Being table to differentiate this is
useful both to track where the actual query is coming from, and to see
if there are differences in executions between the two.

To do this, add a boolean to the hash key indicating if the statement
was top level or not.

Experience from the pg_stat_kcache module shows that in at least some
"reasonable worloads" only <5% of the queries show up both top level and
nested. Based on this, admittedly small, dataset, this patch does not
try to de-duplicate those query *texts*, and will just store one copy
for the top level and one for the nested.

Author: Julien Rohaud
Reviewed-By: Magnus Hagander, Masahiro Ikeda
Discussion: https://postgr.es/m/20201202040516.GA43757@nol
2021-04-08 10:30:34 +02:00

389 lines
9.8 KiB
PL/PgSQL

CREATE EXTENSION pg_stat_statements;
--
-- simple and compound statements
--
SET pg_stat_statements.track_utility = FALSE;
SET pg_stat_statements.track_planning = TRUE;
SELECT pg_stat_statements_reset();
SELECT 1 AS "int";
SELECT 'hello'
-- multiline
AS "text";
SELECT 'world' AS "text";
-- transaction
BEGIN;
SELECT 1 AS "int";
SELECT 'hello' AS "text";
COMMIT;
-- compound transaction
BEGIN \;
SELECT 2.0 AS "float" \;
SELECT 'world' AS "text" \;
COMMIT;
-- compound with empty statements and spurious leading spacing
\;\; SELECT 3 + 3 \;\;\; SELECT ' ' || ' !' \;\; SELECT 1 + 4 \;;
-- non ;-terminated statements
SELECT 1 + 1 + 1 AS "add" \gset
SELECT :add + 1 + 1 AS "add" \;
SELECT :add + 1 + 1 AS "add" \gset
-- set operator
SELECT 1 AS i UNION SELECT 2 ORDER BY i;
-- ? operator
select '{"a":1, "b":2}'::jsonb ? 'b';
-- cte
WITH t(f) AS (
VALUES (1.0), (2.0)
)
SELECT f FROM t ORDER BY f;
-- prepared statement with parameter
PREPARE pgss_test (int) AS SELECT $1, 'test' LIMIT 1;
EXECUTE pgss_test(1);
DEALLOCATE pgss_test;
SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
--
-- CRUD: INSERT SELECT UPDATE DELETE on test table
--
SELECT pg_stat_statements_reset();
-- utility "create table" should not be shown
CREATE TEMP TABLE test (a int, b char(20));
INSERT INTO test VALUES(generate_series(1, 10), 'aaa');
UPDATE test SET b = 'bbb' WHERE a > 7;
DELETE FROM test WHERE a > 9;
-- explicit transaction
BEGIN;
UPDATE test SET b = '111' WHERE a = 1 ;
COMMIT;
BEGIN \;
UPDATE test SET b = '222' WHERE a = 2 \;
COMMIT ;
UPDATE test SET b = '333' WHERE a = 3 \;
UPDATE test SET b = '444' WHERE a = 4 ;
BEGIN \;
UPDATE test SET b = '555' WHERE a = 5 \;
UPDATE test SET b = '666' WHERE a = 6 \;
COMMIT ;
-- many INSERT values
INSERT INTO test (a, b) VALUES (1, 'a'), (2, 'b'), (3, 'c');
-- SELECT with constants
SELECT * FROM test WHERE a > 5 ORDER BY a ;
SELECT *
FROM test
WHERE a > 9
ORDER BY a ;
-- SELECT without constants
SELECT * FROM test ORDER BY a;
-- SELECT with IN clause
SELECT * FROM test WHERE a IN (1, 2, 3, 4, 5);
SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
--
-- INSERT, UPDATE, DELETE on test table to validate WAL generation metrics
--
SELECT pg_stat_statements_reset();
-- utility "create table" should not be shown
CREATE TABLE pgss_test (a int, b char(20));
INSERT INTO pgss_test VALUES(generate_series(1, 10), 'aaa');
UPDATE pgss_test SET b = 'bbb' WHERE a > 7;
DELETE FROM pgss_test WHERE a > 9;
-- DROP test table
SET pg_stat_statements.track_utility = TRUE;
DROP TABLE pgss_test;
SET pg_stat_statements.track_utility = FALSE;
-- Check WAL is generated for the above statements
SELECT query, calls, rows,
wal_bytes > 0 as wal_bytes_generated,
wal_records > 0 as wal_records_generated,
wal_records = rows as wal_records_as_rows
FROM pg_stat_statements ORDER BY query COLLATE "C";
--
-- pg_stat_statements.track = none
--
SET pg_stat_statements.track = 'none';
SELECT pg_stat_statements_reset();
SELECT 1 AS "one";
SELECT 1 + 1 AS "two";
SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
--
-- pg_stat_statements.track = top
--
SET pg_stat_statements.track = 'top';
SELECT pg_stat_statements_reset();
DO LANGUAGE plpgsql $$
BEGIN
-- this is a SELECT
PERFORM 'hello world'::TEXT;
END;
$$;
-- PL/pgSQL function
CREATE FUNCTION PLUS_TWO(i INTEGER) RETURNS INTEGER AS $$
DECLARE
r INTEGER;
BEGIN
SELECT (i + 1 + 1.0)::INTEGER INTO r;
RETURN r;
END; $$ LANGUAGE plpgsql;
SELECT PLUS_TWO(3);
SELECT PLUS_TWO(7);
-- SQL function --- use LIMIT to keep it from being inlined
CREATE FUNCTION PLUS_ONE(i INTEGER) RETURNS INTEGER AS
$$ SELECT (i + 1.0)::INTEGER LIMIT 1 $$ LANGUAGE SQL;
SELECT PLUS_ONE(8);
SELECT PLUS_ONE(10);
SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
--
-- pg_stat_statements.track = all
--
SET pg_stat_statements.track = 'all';
SELECT pg_stat_statements_reset();
-- we drop and recreate the functions to avoid any caching funnies
DROP FUNCTION PLUS_ONE(INTEGER);
DROP FUNCTION PLUS_TWO(INTEGER);
-- PL/pgSQL function
CREATE FUNCTION PLUS_TWO(i INTEGER) RETURNS INTEGER AS $$
DECLARE
r INTEGER;
BEGIN
SELECT (i + 1 + 1.0)::INTEGER INTO r;
RETURN r;
END; $$ LANGUAGE plpgsql;
SELECT PLUS_TWO(-1);
SELECT PLUS_TWO(2);
-- SQL function --- use LIMIT to keep it from being inlined
CREATE FUNCTION PLUS_ONE(i INTEGER) RETURNS INTEGER AS
$$ SELECT (i + 1.0)::INTEGER LIMIT 1 $$ LANGUAGE SQL;
SELECT PLUS_ONE(3);
SELECT PLUS_ONE(1);
SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
--
-- queries with locking clauses
--
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();
-- control query
SELECT * FROM pgss_a JOIN pgss_b ON pgss_b.a_id = pgss_a.id;
-- test range tables
SELECT * FROM pgss_a JOIN pgss_b ON pgss_b.a_id = pgss_a.id FOR UPDATE;
SELECT * FROM pgss_a JOIN pgss_b ON pgss_b.a_id = pgss_a.id FOR UPDATE OF pgss_a;
SELECT * FROM pgss_a JOIN pgss_b ON pgss_b.a_id = pgss_a.id FOR UPDATE OF pgss_b;
SELECT * FROM pgss_a JOIN pgss_b ON pgss_b.a_id = pgss_a.id FOR UPDATE OF pgss_a, pgss_b; -- matches plain "FOR UPDATE"
SELECT * FROM pgss_a JOIN pgss_b ON pgss_b.a_id = pgss_a.id FOR UPDATE OF pgss_b, pgss_a;
-- test strengths
SELECT * FROM pgss_a JOIN pgss_b ON pgss_b.a_id = pgss_a.id FOR NO KEY UPDATE;
SELECT * FROM pgss_a JOIN pgss_b ON pgss_b.a_id = pgss_a.id FOR SHARE;
SELECT * FROM pgss_a JOIN pgss_b ON pgss_b.a_id = pgss_a.id FOR KEY SHARE;
-- test wait policies
SELECT * FROM pgss_a JOIN pgss_b ON pgss_b.a_id = pgss_a.id FOR UPDATE NOWAIT;
SELECT * FROM pgss_a JOIN pgss_b ON pgss_b.a_id = pgss_a.id FOR UPDATE SKIP LOCKED;
SELECT calls, query FROM pg_stat_statements ORDER BY query COLLATE "C";
DROP TABLE pgss_a, pgss_b CASCADE;
--
-- utility commands
--
SET pg_stat_statements.track_utility = TRUE;
SELECT pg_stat_statements_reset();
SELECT 1;
CREATE INDEX test_b ON test(b);
DROP TABLE test \;
DROP TABLE IF EXISTS test \;
DROP FUNCTION PLUS_ONE(INTEGER);
DROP TABLE IF EXISTS test \;
DROP TABLE IF EXISTS test \;
DROP FUNCTION IF EXISTS PLUS_ONE(INTEGER);
DROP FUNCTION PLUS_TWO(INTEGER);
SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
--
-- Track the total number of rows retrieved or affected by the utility
-- commands of COPY, FETCH, CREATE TABLE AS, CREATE MATERIALIZED VIEW,
-- REFRESH MATERIALIZED VIEW and SELECT INTO
--
SELECT pg_stat_statements_reset();
CREATE TABLE pgss_ctas AS SELECT a, 'ctas' b FROM generate_series(1, 10) a;
SELECT generate_series(1, 10) c INTO pgss_select_into;
COPY pgss_ctas (a, b) FROM STDIN;
11 copy
12 copy
13 copy
\.
CREATE MATERIALIZED VIEW pgss_matv AS SELECT * FROM pgss_ctas;
REFRESH MATERIALIZED VIEW pgss_matv;
BEGIN;
DECLARE pgss_cursor CURSOR FOR SELECT * FROM pgss_matv;
FETCH NEXT pgss_cursor;
FETCH FORWARD 5 pgss_cursor;
FETCH FORWARD ALL pgss_cursor;
COMMIT;
SELECT query, plans, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
--
-- Track user activity and reset them
--
SELECT pg_stat_statements_reset();
CREATE ROLE regress_stats_user1;
CREATE ROLE regress_stats_user2;
SET ROLE regress_stats_user1;
SELECT 1 AS "ONE";
SELECT 1+1 AS "TWO";
RESET ROLE;
SET ROLE regress_stats_user2;
SELECT 1 AS "ONE";
SELECT 1+1 AS "TWO";
RESET ROLE;
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 query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
--
-- remove query ('SELECT $1+$2 AS "TWO"') executed by regress_stats_user2
-- in the current_database
--
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));
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)
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)
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 query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
--
-- cleanup
--
DROP ROLE regress_stats_user1;
DROP ROLE regress_stats_user2;
DROP MATERIALIZED VIEW pgss_matv;
DROP TABLE pgss_ctas;
DROP TABLE pgss_select_into;
--
-- [re]plan counting
--
SELECT pg_stat_statements_reset();
CREATE TABLE test ();
PREPARE prep1 AS SELECT COUNT(*) FROM test;
EXECUTE prep1;
EXECUTE prep1;
EXECUTE prep1;
ALTER TABLE test ADD COLUMN x int;
EXECUTE prep1;
SELECT 42;
SELECT 42;
SELECT 42;
SELECT query, plans, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
--
-- access to pg_stat_statements_info view
--
SELECT pg_stat_statements_reset();
SELECT dealloc FROM pg_stat_statements_info;
--
-- top level handling
--
SET pg_stat_statements.track = 'top';
DELETE FROM test;
DO $$
BEGIN
DELETE FROM test;
END;
$$ LANGUAGE plpgsql;
SELECT query, toplevel, plans, calls FROM pg_stat_statements WHERE query LIKE '%DELETE%' ORDER BY query COLLATE "C", toplevel;
SET pg_stat_statements.track = 'all';
DELETE FROM test;
DO $$
BEGIN
DELETE FROM test;
END;
$$ LANGUAGE plpgsql;
SELECT query, toplevel, plans, calls FROM pg_stat_statements WHERE query LIKE '%DELETE%' ORDER BY query COLLATE "C", toplevel;
DROP EXTENSION pg_stat_statements;