Re: Messed up time zones - Mailing list pgsql-admin

From JC de Villa
Subject Re: Messed up time zones
Date
Msg-id CAOvw+NbE-x8UoNw6WX69dAyPOh0nPf8Qqtmsf_0c46QE51Zi0Q@mail.gmail.com
Whole thread Raw
In response to Re: Messed up time zones  (Laszlo Nagy <gandalf@shopzeus.com>)
List pgsql-admin


On Fri, Aug 3, 2012 at 5:18 PM, Laszlo Nagy <gandalf@shopzeus.com> wrote:


Isn't:

select now() at time zone 'Australia/ATC' 

supposed to be:

select now() at time zone 'Australia/ACT'
I see now. The abbreviation is usually a time zone name. But to be correct, the time zone name should be used (and not the abbreviation).


And looking at the pg_timezone_names table for EST, there's only one entry for EST:

SELECT * from pg_timezone_names where name = 'EST';
 name | abbrev | utc_offset | is_dst 
------+--------+------------+--------
 EST  | EST    | -05:00:00  | f

Okay, but that is the "name", and not the "abbrev" field. So time zone abbreviations are not unique? Then probably it is my fault - I thought that they will be unique. It is still an interesting question, how others interpret these (non-unique) abbreviations? But I guess that is not related to PostgreSQL so I'm being offtopic here.


One last question. Am I right in that PostgreSQL does not handle leap seconds?

template1=> set time zone 'UTC';
template1=> select '2008-12-31 23:59:60'::timestamp;
      timestamp     
---------------------
 2009-01-01 00:00:00
(1 row)

And probably intervals are affected too:

template1=> set time zone 'UTC';
template1=> select '2008-12-31 00:00:00'::timestamp + '48 hours'::interval;
      timestamp     
---------------------
 2009-01-02 00:00:00
(1 row)

Should be '2009-01-01 23:59:59' instead.

Thanks,

   Laszlo



Well, per the docs at http://www.postgresql.org/docs/9.1/static/functions-datetime.html,  in parens under timezone:

"Technically, PostgreSQL uses UT1because leap seconds are not handled."

Although there is a footnote on that page that states that:

"60 if leap seconds are implemented by the operating system".

-- 
JC de Villa

pgsql-admin by date:

Previous
From: Laszlo Nagy
Date:
Subject: Re: Messed up time zones
Next
From: Laszlo Nagy
Date:
Subject: Re: Messed up time zones