[postgis-devel] GBOXF

[Mark Cave-Ayland]

On 29/11/11 21:51, Sandro Santilli wrote:

>> Another case to think about would be GROUP BY, which works by
>> performing an equality comparison between bounding boxes - again,
>> two very similar yet distinct geometries could be considered equal.
>
> This is also true for two very different geometries yet having
> the same bounding box, so doesn't seem a good example to me.
> Ie:
>
>   LINESTRING(0 0, 10 0, 10 10)
>   LINESTRING(0 0, 10 10)
>
> I guess you were referring once again only to points ?

No, that would include polygons as well. I'm fairly sure that Paul has 
used the bounding box GROUP BY as part of one of his many tutorials.


ATB,

Mark.

-- 
Mark Cave-Ayland - Senior Technical Architect
PostgreSQL - PostGIS
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