Re: Timezone database changes

"Trevor Talbot" <quension@gmail.com> writes:
> Actually, what I meant at least (not sure if others meant it), is
> storing the value in the timezone it was entered, along with what zone
> that was.  That makes the value stable with respect to the zone it
> belongs to, instead of being stable with respect to UTC.  When DST
> rules change, the value is in effect "reinterpreted" as if it were
> input using the new rules.

What happens if the rules change in a way that makes the value illegal
or ambiguous (ie, it now falls into a DST gap)?

But perhaps more to the point, please show use-cases demonstrating that
this behavior is more useful than the pure-UTC behavior.  For storage of
actual time observations, I think pure-UTC is unquestionably the more
useful.  Peter's example of a future appointment time is a possible
counterexample, but as observed upthread it's hardly clear which
behavior is more desirable in such a case.
        regards, tom lane