[udig-devel] intersection/disjunction of layers?

[Vince Darley]

I have several layers related to a road network.  Each is composed of 
LineStrings or similar.  These layers are all different views/subsets 
of an underlying postgres table of road segments -- all referenced by 
a primary "road segment id" key.

I'm wondering if uDig (or any community plugins) provide an easy way 
to see, for any pair of such layers, which road segments are shared 
by the two layers and which are not shared - i.e. intersection and 
disjunction of the sets of road segments.

Any known capabilities which cover this?

regards,

Vince.