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

[Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>]

"Alistair Bayley" <alistair(at)abayley(dot)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