[postgis-users] topology : statue of topogeom composition?

[Sandro Santilli]

On Thu, Nov 12, 2015 at 06:43:03PM +0100, Rémi Cura wrote:

> First of all is it possible to have topogeometry composed of other
> topogeometry, themselves composed of other geometry, and so one?

Yes, when the TopoGeometry layer is a "hierarchical layer"
(has a not null "child_layer" value in topology.layer) then
the "type" field of its TopoElements references its child layer
id and the "id" field references the identifier of a coposing
TopoGeometry object.

> Second,
> if this is possible, are this kind of topogeometry properly maintained when
> there is a change in the low level topology (splitting an edge for
> instance).

The upper levels are composed by the lower levels.
The lowest levels (primitive layers) are properly maintained
and thus the higher one are too.

--strk;

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