Drawing collected multipolygons from PostGIS...

[Matthew Perry]

On 5/16/07, John Cole <john.cole at uai.com> wrote:
> Hello,
>   I'm trying to "pretty" up a polygon layer (specifically tiger placecu).
> I'd like to draw an outline of a collection of multipolygon objects, but it
> doesn't seem to be working.
>
> Here is my data statement in my mapfile:
>
>         DATA "the_geom from (SELECT min(gid) as gid, collect(the_geom) as the_geom
> from placecu
> WHERE (gid = any (string_to_array('%PLCGID%', '^')))
> and (the_geom && setSRID(!BOX!, 4326)) group by name) foo USING SRID=4326,
> USING UNIQUE gid"
>
> If I remove the min/collect the layer draws fine, but I was hoping to get
> the exterior ring of the combined polygons and draw that.  Has anyone done
> something similar?  I'd love an example.

Have you tried BuildArea(collect(the_geom)) ?

-- 
Matthew T. Perry
http://www.perrygeo.net

"You never change things by fighting the existing reality.
To change something, build a new model that makes
the existing model obsolete" - R. Buckminster Fuller