"Peter J. Holzer" <hjp-pgsql@xxxxxx> writes: > On 2025-01-27 21:01:59 +0000, Nem Tudom wrote: >> I thought that the EPOCH was the number of seconds since 1970-01-01 >> 00:00:00? Is this incorrect? > The POSIX standard mandates that leap seconds must be ignored. It's not > really "number of seconds since 1970-01-01", but "number of days since > 1970-01-01 times 86400 plus number of seconds in the current day". I'm not sure what POSIX says about this, but that is the definition Postgres uses --- and we won't let you select a timezone setting that does account for leap seconds. postgres=# set timezone = 'America/New_York'; SET postgres=# set timezone = 'right/America/New_York'; ERROR: time zone "right/America/New_York" appears to use leap seconds DETAIL: PostgreSQL does not support leap seconds. If we did support that, it'd enormously complicate all timestamp arithmetic --- and we could hardly do calculations with times in the future at all, given the uncertainty around when leap seconds will be declared. So if you want to do astronomical timekeeping, you should use some other data type than timestamptz. regards, tom lane
