Re: What's special about 1916-10-01 02:25:20? Odd jump in internal timestamptz representation

"Alistair Bayley" <alistair@abayley.org> writes:
> Actually, looking at the code again, I can see what happens, I think.
> This entry in win32_tzmap maps my GMT timezone to PG's Europe/Dublin
> timezone:
>     {
>         "GMT Standard Time", "GMT Daylight Time",
>         "Europe/Dublin"
>     },                            /* (GMT) Greenwich Mean Time : Dublin,
>                                  * Edinburgh, Lisbon, London */

Oh, you didn't say you were on Windows --- that changes things entirely.
That code doesn't try to probe the system behavior, it just has a
hardwired mapping.

Magnus, did you have a specific reason for choosing Europe/Dublin,
or was it just alphabetically first?  Europe/London looks at least
marginally closer to what one would think "GMT" means:

Zone    Europe/London    -0:01:15 -    LMT    1847 Dec  1
             0:00    GB-Eire    %s    1968 Oct 27
             1:00    -    BST    1971 Oct 31 2:00u
             0:00    GB-Eire    %s    1996
             0:00    EU    GMT/BST

Zone    Europe/Dublin    -0:25:00 -    LMT    1880 Aug  2
            -0:25:21 -    DMT    1916 May 21 2:00
            -0:25:21 1:00    IST    1916 Oct  1 2:00s
             0:00    GB-Eire    %s    1921 Dec  6 # independence
             0:00    GB-Eire    GMT/IST    1940 Feb 25 2:00
             0:00    1:00    IST    1946 Oct  6 2:00
             0:00    -    GMT    1947 Mar 16 2:00
             0:00    1:00    IST    1947 Nov  2 2:00
             0:00    -    GMT    1948 Apr 18 2:00
             0:00    GB-Eire    GMT/IST    1968 Oct 27
             1:00    -    IST    1971 Oct 31 2:00u
             0:00    GB-Eire    GMT/IST    1996
             0:00    EU    GMT/IST

            regards, tom lane