postgres=# show intervalstyle;
 IntervalStyle 
---------------
 postgres
(1 row)

With Default setting:
---------------------
Pub:
CREATE TABLE tab1 (k interval PRIMARY KEY, v text);
INSERT INTO tab1 VALUES (interval '-1 day -2 hours', 'a'),
                        (interval '-3 days -4 hours', 'b');
CREATE PUBLICATION pub1 FOR TABLE tab1;

Sub:
CREATE TABLE tab1 (k interval PRIMARY KEY, v text);
CREATE SUBSCRIPTION sub1 connection '...' publication pub1 WITH(conflict_log_destination='all');

-- after initial sync, make both rows "missing":
SELECT * from tab1;
         k         | v 
-------------------+---
 -1 days -02:00:00 | a
 -3 days -04:00:00 | b
(2 rows)

DELETE FROM tab1;

Pub:
--this will cause conflict #1
UPDATE tab1 SET v = 'a2' WHERE k = interval '-1 day -2 hours';

Sub:
--normal so far, RI value is correctly shown
SELECT replica_identity->>'k'              AS stored_text,
       (replica_identity->>'k')::interval  AS read_by_default_reader,
       remote_commit_ts
FROM   pg_conflict.pg_conflict_log_16392
ORDER  BY remote_commit_ts;



With Changed setting:
---------------------
Sub:
ALTER SYSTEM SET intervalstyle = 'sql_standard';
SELECT pg_reload_conf();

Pub:
--this will cause conflict #2
UPDATE tab1 SET v = 'b2' WHERE k = interval '-3 days -4 hours';

Sub:
--The true key on the publisher was -3 days -4 hours (i.e. -3 days -04:00:00).
--The CLT stored it as -3 4:00:00 in compact 'sql_standard' format where one sign ('-' here) is used for entire uniformly-negative value.
--Reading that stored text back with the default 'postgres' style gives -3 days +04:00:00. (in 'postgres' style each value should be prefixed with sign, 
so lack of sign was read as '+', leading to correctness issue.)


SET intervalstyle = postgres;
SELECT replica_identity->>'k'              AS stored_text,
       (replica_identity->>'k')::interval  AS read_by_default_reader,
       remote_commit_ts
FROM   pg_conflict.pg_conflict_log_16392
ORDER  BY remote_commit_ts;

======================



BEFORE FIX: (See second values in read_by_default_reader)

SET intervalstyle = postgres;
postgres=# SELECT replica_identity->>'k'              AS stored_text,
       (replica_identity->>'k')::interval  AS read_by_default_reader,
       remote_commit_ts
FROM   pg_conflict.pg_conflict_log_16392
ORDER  BY remote_commit_ts;
    stored_text    | read_by_default_reader |         remote_commit_ts         
-------------------+------------------------+----------------------------------
 -1 days -02:00:00 | -1 days -02:00:00      | 2026-10-13 15:33:55.853625+05:30
 -3 4:00:00        | -3 days +04:00:00      | 2026-10-13 15:35:42.014081+05:30
(2 rows)



AFTER fix: same steps, worker still at intervalstyle='sql_standard' when conflict #2 fires. The stored value is now correct regardless of the worker’s setting.

postgres=# SET intervalstyle = postgres;
SELECT replica_identity->>'k'              AS stored_text,
       (replica_identity->>'k')::interval  AS read_by_default_reader,
       remote_commit_ts
FROM   pg_conflict.pg_conflict_log_16392
ORDER  BY remote_commit_ts;
SET
    stored_text    | read_by_default_reader |         remote_commit_ts         
-------------------+------------------------+----------------------------------
 -1 days -02:00:00 | -1 days -02:00:00      | 2026-10-13 15:45:40.467277+05:30
 -3 days -04:00:00 | -3 days -04:00:00      | 2026-10-13 15:46:04.749876+05:30
(2 rows)