[postgis-devel] KNN and Semantics

[Sandro Santilli]

On Tue, Sep 27, 2011 at 08:53:46AM +0200, Nicklas Avén wrote:

> What we then need to do is iterate the list, send the real geometries to
> the ordinary distance function and stop at once the next incoming
> bounding box is more far away than the closest real distance ( or n:ths
> closest real distance if limit is more than 1)

Agreed. Using boxes gives us a meaningful stop condition.
This is assuming the user wants the get objects within a given distance.

If the user wants the # objects in distance order she will be back
to magic numbers.

But at least with boxes we do havea non-magic number to deal with for
the first case.

--strk;

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