Re: IANA timezone abbreviations versus timezone_abbreviations

On Mon, Dec 16, 2024 at 02:57:59PM -0500, Tom Lane wrote:
> Andreas Karlsson <andreas@proxel.se> writes:
> > On 12/13/24 12:33 AM, Tom Lane wrote:
> >> What I think we should do about this is to teach timestamp
> >> input to look into the current IANA time zone to see if it
> >> knows the given abbreviation, and if so use that meaning
> >> regardless of what timezone_abbreviations might say.
> 
> > I am not convinced this is an improvement. While this patch removes the 
> > round-trip hazard it also makes it confusing to use the 
> > timezone_abbreviations GUC since it can be overridden by IANA data based 
> > on your current timezone. So you need to know all the, sometimes weird, 
> > names for your current timezone. Seems unnecessarily hard to reason 
> > about and wouldn't most people who use timezone_abbreviations rely on 
> > the current behavior?
> 
> Presumably they're not that weird to the locals?
> 
> I am not sure what you mean by "people who use
> timezone_abbreviations".  I think that's about everyone --- it's
> not like the default setting doesn't contain any abbreviations.
> (If it didn't then we'd not have such a problem...)
> 
> > But that said I personally only use ISO timestamps with numerical 
> > offsets. Partially to avoid all this mess.
> 
> If you only use ISO notation then this doesn't matter to you
> either way.

Yes, your patch seems like a big improvement.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

  Do not let urgent matters crowd out time for investment in the future.