[postgis-devel] Geometry emptiness explained (was Re: GML for empty geometries ?)

[Mark Cave-Ayland]

On 14/12/11 20:02, Mateusz Łoskot wrote:

> On 14 December 2011 17:18, Paul Ramsey<pramsey at opengeo.org>  wrote:
>> Based on 30 seconds of research I'd say go with NULL as the return for
>> empty geometries.
>> Yes, 'POINT EMPTY' (and all the other typological variants) is legal
>> in WKT. (But the concept of EMPTY appears completely ignored in all
>> discussions of WKB.) (Standards rule.)
>
> I dare to hijack the thread and ask, would it be a good idea
> if PostGIS documentation includes explanation of empty geometries
> according to popular specifications, at least those supported as input/output
> (GML, WKT, WKB, GeoJSON)?
> Q&A in one place, easily reachable for users, presumably in the FAQ.

We already thrashed out a lot of the logic here: 
http://trac.osgeo.org/postgis/wiki/DevWikiEmptyGeometry so I'd suggest 
adding the information to this page.


ATB,

Mark.

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