Ühel kenal päeval, R, 2007-02-16 kell 17:39, kirjutas Alvaro Herrera:
> Jim C. Nasby wrote:
> > My suggestion would be to focus on a period data type first and
> > foremost, as that's something that could be readily used by a lot of
> > folks. Of particular note, it's difficult to query tables that have
> > start_time and end_time fields to define a period; it's easy to screw up
> > the boundary conditions, and it's also hard to make those queries
> > perform well without going to extra lengths (such as defining a 'bogus'
> > GiST index on something like box(point(start,start),point(end,end)). And
> > it's not possible to do that in a way that avoids floating points and
> > their errors.
>
> FWIW there's already a type called tinterval that stores (start,end). I
> don't think it's very much documented; maybe it can be extended or used
> as base for a new, more complete and robust type, indexable in a more
> natural way, etc etc.
How easy/hard would it be to create unique indexes on tinterval (unique
here meaning non-overlapping) ?
Is tinterval meant to be open/closed at start and end ?
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