The following bug has been logged on the website:
Bug reference: 17866
Logged by: Евгений Жужнев
Email address: eugeny(at)zhuzhnev(dot)com
PostgreSQL version: 15.2
Operating system: Oracle Linux 9
Description:
sudo -u postgres psql pgc
psql (15.2)
Type "help" for help.
pgc=# SELECT EXTRACT(EPOCH FROM INTERVAL '5 days 3 hours');
extract
---------------
442800.000000
(1 row)
--
But in documentation we can see:
SELECT EXTRACT(EPOCH FROM INTERVAL '5 days 3 hours');
Result: 442800
https://www.postgresql.org/docs/current/functions-datetime.html