Re: timezones BCE

On Wed, 13 Apr 2022 at 14:10, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> chap(at)anastigmatix(dot)net writes:
> > On 2022-04-13 12:33, Dave Cramer wrote:
> >> 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.
>
> Yeah, you'll see these weird offsets in just about every zone for dates
> earlier than the late 1800s. I've got my doubts about how useful it is
> to do that, but that's the policy the tzdb guys have.
>
> At one point I was considering whether we could project the oldest
> recorded "standard time" offset backwards instead of believing the LMT
> offsets. This would confuse many fewer people, and it's no less
> logically defensible than applying the Gregorian calendar to years
> centuries before Pope Gregory was born. But I fear that horse may
> have left the barn already --- changing this behavior would have
> its own downsides, and I do not think any other tzdb consumers do it.
>

Oh please don't do something bespoke. I'm trying to make this work with the
JDBC driver.
So it has to be at least compatible with other libraries.

Dave