Re: WIP: generalized index constraints

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On Tue, Sep 15, 2009 at 10:28:28AM -0700, Jeff Davis wrote:
> On Tue, 2009-09-15 at 13:16 -0400, Robert Haas wrote:
> > Uhh.... so what happens if I create an index constraint using the
> > +(integer, integer) operator?
>
> You can use any operator that has an index search strategy. Overlaps is
> probably the most useful, but you could imagine other operators, like a
> bi-directional containment operator (either LHS is contained in RHS, or
> vice-versa).
>
> You can also get creative and have a "similarity" operator that
> determines whether two tuples are "too similar". As long as it is
> symmetric, the feature will work.

One question: does the operator have to be reflexive? I.e. "A op A holds
for all A"?

I am thinking "proximity" or as you state above "similarity". May be
this is a good metaphor, leading to a good name.

Regards
- -- tomás
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