-- test/sql/vacuum_pending_dead.sql
--
-- A dead TID still in the pending list must not outlive its heap tuple.
--
-- ambulkdelete stripped dead TIDs only from the posting trees.  A row
-- inserted and deleted between two VACUUMs is still in the pending list,
-- so it survived the strip, was merged into a tree by amvacuumcleanup
-- right after, and stayed there -- while the heap freed the line pointer
-- and truncated the block.  The next index scan fetched a TID past the
-- heap's end: "could not read blocks 1..1 ... read only 0 of 8192 bytes"
-- (field report 2026-09-29).  ambulkdelete now merges the pending list
-- first, as ginbulkdelete does.
CREATE EXTENSION IF NOT EXISTS pg_tre;
psql:test/sql/vacuum_pending_dead.sql:14: NOTICE:  extension "pg_tre" already exists, skipping
CREATE EXTENSION
DROP TABLE IF EXISTS vpd;
psql:test/sql/vacuum_pending_dead.sql:16: NOTICE:  table "vpd" does not exist, skipping
DROP TABLE
CREATE TABLE vpd (id serial PRIMARY KEY, body text)
    WITH (autovacuum_enabled = off);
CREATE TABLE
SET client_min_messages = warning;
SET
CREATE INDEX vpd_tre ON vpd USING tre (body);
CREATE INDEX
RESET client_min_messages;
RESET
-- Fills several heap blocks; every entry goes to the pending list.
INSERT INTO vpd (body)
SELECT 'ghost_' || g || repeat(' pad', 40) FROM generate_series(1, 5000) g;
INSERT 0 5000
SELECT pg_relation_size('vpd') / 8192 > 1 AS several_heap_blocks;
 several_heap_blocks 
---------------------
 t
(1 row)

DELETE FROM vpd;
DELETE 5000
VACUUM vpd;
VACUUM
SELECT pg_relation_size('vpd') AS heap_bytes_after_truncate;
 heap_bytes_after_truncate 
---------------------------
                         0
(1 row)

INSERT INTO vpd (body) VALUES ('alive');
INSERT 0 1
SET enable_seqscan = off;
SET
SELECT count(*) AS ghosts_via_index FROM vpd WHERE body ~ 'ghost_4';
 ghosts_via_index 
------------------
                0
(1 row)

SELECT count(*) AS alive_via_index FROM vpd WHERE body ~ 'alive';
 alive_via_index 
-----------------
               1
(1 row)

RESET enable_seqscan;
RESET
-- Same through flush_to_run, whose merges land in catalog runs rather
-- than the base tree; ambulkdelete must walk those too.
TRUNCATE vpd;
psql:test/sql/vacuum_pending_dead.sql:41: NOTICE:  pg_tre: collected 0 trigram entries from 0 heap tuples
psql:test/sql/vacuum_pending_dead.sql:41: NOTICE:  pg_tre: built 0 posting trees
psql:test/sql/vacuum_pending_dead.sql:41: NOTICE:  pg_tre: build complete, indexed 0 heap tuples into 0 trigrams
TRUNCATE TABLE
SET pg_tre.flush_to_run = on;
SET
INSERT INTO vpd (body)
SELECT 'wraith_' || g || repeat(' pad', 40) FROM generate_series(1, 5000) g;
INSERT 0 5000
VACUUM vpd;                 -- flushes the pending list into a run
VACUUM
DELETE FROM vpd;
DELETE 5000
VACUUM vpd;
VACUUM
RESET pg_tre.flush_to_run;
RESET
INSERT INTO vpd (body) VALUES ('alive');
INSERT 0 1
SET enable_seqscan = off;
SET
SELECT count(*) AS wraiths_via_index FROM vpd WHERE body ~ 'wraith_4';
 wraiths_via_index 
-------------------
                 0
(1 row)

RESET enable_seqscan;
RESET
DROP TABLE vpd;
DROP TABLE