Re: Range types

On Tue, Dec 15, 2009 at 11:31:05AM -0800, Scott Bailey wrote:
> Jeff Davis wrote:
> >On Tue, 2009-12-15 at 10:19 -0500, Tom Lane wrote:
>
> Would it be OK if we handled float timestamp ranges as continuous
> and int64 timestamps discrete?

That sounds like a recipe for disaster. Whatever timestamp ranges
are, float and int64 should be treated the same way so as not to get
"surprises" due to implementation details.

> You effectively lose the ability to build non-contiguous sets with
> continuous ranges. Which is integral to the work I'm doing (union,
> intersect, coalesce and minus sets of ranges)
>
> As for the extra bits, would it be better to just require continuous
> ranges to be either [] or [)? But I don't know which would be
> preferred. My inclination would be toward [), but Tom seemed to
> indicate that perhaps [] was the norm.

[] makes certain operations--namely the important ones in
calendaring--impossible, or at least incredibly kludgy, to do. I
think we ought to leave openness at each end up to the user,
independent of the underlying implementation details.

FWIW, I think it would be a good idea to treat timestamps as
continuous in all cases.

Cheers,
David.
--
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