John, a collection does not polygon make. A collection is more like an
array of polygons and any array doe not have an exterior ring.
You might try replacing collect(the_geom) with MemGeomUnion(the_geom)
and see if you have any luck with that. It might be too slow.
-Steve W.
John Cole 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.
Thanks,
John
