Re: ISO 8601 "Time Intervals" of the "format with time-unit deignators"

Tom wrote:
> "Ron Mayer" <ron@intervideo.com> writes:
> > Tom wrote:
> >> Er, don't we support that already?
> > ...AFAICT, doesn't match ISO 8601...
>
> Well, it's *supposed* to match ISO....  Unless ISO has put out
> multiple specs that cover this?

Any way to tell if this is the case.
8601's the one I see cited the most.


> > ...I'd not want to break backward compatability...'1H30M'
>
> I doubt anyone is using it, because it's completely undocumented.
> If we're going to support the real ISO spec, I'd suggest ripping
> out any not-quite-there variant.

I'm happy to look into it.  Rip out completely?  Ifdef?

> We've been gradually cleaning up the problems, but if if you find
> something that doesn't seem to make sense, it's likely a bug rather
> than anything we want to preserve.

I've seen a few more cases that don't make sense.

For example "why is 0.001 years less than 0.001 months".

  betadb=# select '0.01 years'::interval
   interval
  ----------
   00:00:00

  betadb=# select '0.01 months'::interval
   interval
  ----------
   07:12:00

If I'm breaking backward compatability anyway, I'd be happy to tweak
things like this one too.  Unless, of course someone can give me a
reason why we want fractional years rounded to months, but fractional
months are rounded to fractions of a second.

   Ron Mayer.

PS: mailinglist etiquite question... for discussion, should I
    more this to hackers, or continue it here.