-- P2: TRUNCATE followed, in the same transaction, by work that is undone or
-- by an ANALYZE, leaves wrong live/dead counts.  Deterministic: no
-- dependency on flush timing.  Runs on 14 and later.
\set ON_ERROR_STOP 1
\pset footer off
SELECT current_setting('server_version_num')::int >= 150000 AS has_force_flush \gset
\if :has_force_flush
\set flush 'SELECT pg_stat_force_next_flush()'
\else
\set flush 'SELECT pg_sleep(1.1)'
\endif

\echo == P2a: BEGIN; TRUNCATE; SAVEPOINT; INSERT 100; ROLLBACK TO; COMMIT
CREATE TABLE p2a (id int) WITH (autovacuum_enabled = off);
BEGIN;
TRUNCATE p2a;
SAVEPOINT s;
INSERT INTO p2a SELECT generate_series(1, 100);
ROLLBACK TO s;
COMMIT;
:flush \g /dev/null
SELECT n_live_tup, n_dead_tup FROM pg_stat_user_tables WHERE relname = 'p2a';
\echo expected n_dead_tup = 100 (the aborted rows are in the new relfilenode); bug: 0
\echo VACUUM VERBOSE shows the 100 dead rows it removes:
VACUUM (VERBOSE) p2a;

\echo == P2a control: same without the TRUNCATE
CREATE TABLE p2a_ctl (id int) WITH (autovacuum_enabled = off);
BEGIN;
SAVEPOINT s;
INSERT INTO p2a_ctl SELECT generate_series(1, 100);
ROLLBACK TO s;
COMMIT;
:flush \g /dev/null
SELECT n_live_tup, n_dead_tup FROM pg_stat_user_tables WHERE relname = 'p2a_ctl';
\echo control gives n_dead_tup = 100

\echo == P2b: 288 rows; BEGIN; SAVEPOINT; TRUNCATE; ANALYZE; ROLLBACK TO; COMMIT
CREATE TABLE p2b (id int) WITH (autovacuum_enabled = off);
INSERT INTO p2b SELECT generate_series(1, 288);
ANALYZE p2b;
:flush \g /dev/null
BEGIN;
SAVEPOINT s;
TRUNCATE p2b;
ANALYZE p2b;
ROLLBACK TO s;
COMMIT;
:flush \g /dev/null
SELECT s.n_live_tup, c.reltuples, (SELECT count(*) FROM p2b) AS count
  FROM pg_stat_user_tables s JOIN pg_class c ON c.oid = s.relid
 WHERE s.relname = 'p2b';
\echo expected n_live_tup = 288; bug: 0.  pg_class.reltuples keeps the right value

\echo == P2b, top-level variant: BEGIN; TRUNCATE; ANALYZE; ROLLBACK
CREATE TABLE p2c (id int) WITH (autovacuum_enabled = off);
INSERT INTO p2c SELECT generate_series(1, 288);
ANALYZE p2c;
:flush \g /dev/null
BEGIN;
TRUNCATE p2c;
ANALYZE p2c;
ROLLBACK;
:flush \g /dev/null
SELECT s.n_live_tup, c.reltuples, (SELECT count(*) FROM p2c) AS count
  FROM pg_stat_user_tables s JOIN pg_class c ON c.oid = s.relid
 WHERE s.relname = 'p2c';

DROP TABLE p2a, p2a_ctl, p2b, p2c;