-- A build opens the tombstone log of an index only when it reads the column format of the log: a log of a newer format may hold records an older build would not keep when it
-- appended, so the older build stops with an error and a hint instead (sift.test_col_log_max_read stands in for the older build).
CREATE EXTENSION pg_sift;
CREATE EXTENSION pg_sift_test;
SET max_parallel_workers_per_gather = 0;
CREATE TABLE t (id int PRIMARY KEY, v int NOT NULL) WITH (autovacuum_enabled = false);
INSERT INTO t SELECT i, i FROM generate_series(1, 1000) i;
CREATE INDEX t_c ON t USING sift_col (id, v);
NOTICE:  sift_col index "t_c": 1 automatic choice (track_changes)
DETAIL:  track_changes = id
HINT:  Reasons, costs and how to turn each off: SELECT * FROM sift.index_choices('t_c');
UPDATE t SET v = v + 1 WHERE id = 1;
SELECT count(*) AS entries FROM sift._test_col_log_entries('t_c');
 entries 
---------
       1
(1 row)

\c -
SET sift.test_col_log_max_read = 42;
UPDATE t SET v = v + 1 WHERE id = 2;
ERROR:  index "t_c" has a tombstone log of column format 1.43, this build reads up to 1.42
HINT:  Use a newer pg_sift, or REINDEX.
DELETE FROM t WHERE id = 3;
ERROR:  index "t_c" has a tombstone log of column format 1.43, this build reads up to 1.42
HINT:  Use a newer pg_sift, or REINDEX.
SELECT count(*) FROM sift._test_col_log_entries('t_c');
ERROR:  index "t_c" has a tombstone log of column format 1.43, this build reads up to 1.42
HINT:  Use a newer pg_sift, or REINDEX.
\c -
SET sift.test_col_log_max_read = 43;
UPDATE t SET v = v + 1 WHERE id = 2;
SELECT count(*) AS entries FROM sift._test_col_log_entries('t_c');
 entries 
---------
       2
(1 row)

DROP TABLE t;
DROP EXTENSION pg_sift_test;
DROP EXTENSION pg_sift;