Re: timezones BCE

From: chap(at)anastigmatix(dot)net
To: Dave Cramer <davecramer(at)gmail(dot)com>
Cc: PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org>
Subject: Re: timezones BCE
Date: 2022-04-13 16:48:10
Message-ID: 17e2658c31d8284355de0d3230445855@anastigmatix.net
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On 2022-04-13 12:33, Dave Cramer wrote:
> test=# set timezone to 'America/Toronto';
> SET
> test=# select '0101-01-01'::timestamptz;
> timestamptz
> ------------------------------
> 0101-01-01 00:00:00-05:17:32
>
> Specifically why the -05:17:32

Timezones were regularized into their (typically hour-wide) chunks
during a period around the late nineteenth century IIRC.

If you decompile the zoneinfo database to look at America/Toronto,
you will probably find an entry for dates earlier than when the
regularized zones were established there, and that entry will have
an offset reflecting Toronto's actual longitude.

Regards,
-Chap

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Zheng Li 2022-04-13 17:22:46 Re: Support logical replication of DDLs
Previous Message Peter Geoghegan 2022-04-13 16:34:22 Re: Improving the "Routine Vacuuming" docs