[fpc-pascal] Timezone information in a dataset datetime field?- updated

[Mark Morgan Lloyd]

DaWorm wrote:
> On Mon, Jul 25, 2011 at 11:53 AM, Mark Morgan Lloyd
> <markMLl.fpc-pascal at telemetry.co.uk> wrote:
>> Link below looks directly relevant: it contains polygon data for each
>> timezone, subject to knowing the current location.
>>
>> http://efele.net/maps/tz/world/
>>
>> I've confirmed that files are accessible (i.e. not subscription-only) but
>> not investigated the format of the content.
> 
> Location may be off too.  All of the online location reporting tool
> lists my work machine as being in TX, even though I'm in TN, since all
> our networks are routed back to the home office before hitting the
> cloud.

Yes, I noticed several ways of getting timezone info knowing a named 
location (I'm reluctant to use the terms "city" or "town" here, since 
they mean different things in different countries) and they obviously 
depend on the apparent location being relevant.

The files I found were the only source of raw geographical data which 
could be used with e.g. a GPS receiver or manual lat/long entry (on or 
over land). Since they appear to contain timezones in the form 
Europe/London they should be compatible with e.g. Postgres's internal 
tables that describe named timezones, although I haven't investigated 
whether there's a one-to-one mapping. I assume that the Postgres files 
are GPL, so could be extracted for other use.

-- 
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk

[Opinions above are the author's, not those of his employers or colleagues]