[postgis-users] exterior rings in multipolygons

[Sandro Santilli]

On Tue, Jul 26, 2011 at 07:16:15AM -0500, Mr. Puneet Kishor wrote:

> Thanks for confirming the above. However, per my follow-up email (see http://postgis.refractions.net/pipermail/postgis-users/2011-July/030366.html), I am not getting the interior rings as polygons. They are coming out as LINESTRINGs. Shouldn't the indivdual components of the MULTIPOLYGON be POLYGONs?

Individual components of MULTIPOLYGONs are POLYGONs.
You get them with ST_GeometryN.
Components of POLYGONs are RINGs.
Ring are represented as closed LINESTRINGS, following OGC spec.
You can make polygons out of closed LINESTRINGs using ST_MakePolygon.

--strk;

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