[postgis-users] Region-style representations

[Tyler Mitchell]

Your definition sounds good enough to me.
The reason this came up is that I'm discussing using postgis with some
other applications which traditionally have created regions in arcinfo for
their analysis.  Is it possible (or going to be possible) to create
multipolygons from polygons within postgis, via some dissolving on an
attribute(s) function?

Tyler


                                                                                                                 
                      Frank Warmerdam                                                                            
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Tyler Mitchell wrote:
> Hi guys,
> Are there plans/possibilities of representing polygons a la ArcInfo
> region-style?  Is this covered off in another OGC spec?

Tyler,

My understanding is that regions in arc/info are a way of making a feature
(with attributes) that consists of one or more simple polygons that may
have
wholes.  That is region is potentially a set of disconnected areas.  In
OGC Simple Features this would be a MultiPolygon geometry and should be
supported directly by PostGIS.

I am not absolutely certain if my OGR region handling actually treats
regions properly as MultiPolygons or not, but if so I would imagine they
could be loaded into PostGIS with ogr2ogr.

Best regards,
--
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I set the clouds in motion - turn up   | Frank Warmerdam,
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