[postgis-users] PostGIS topology use ?

[Stephen Woodbridge]

strk wrote:
> Hello post-GIS users!
> I was wondering how many of you guys (if any) ever
> tried or even currently makes use of the topology
> model provided with PostGIS in the topology/ directory.
> 
> It's been there since 2005 (times of postgis-1.1.x, geos-2.1,
> postgresql-7.3).
> 
> For the record: it has been broken for some time as PostGIS
> changed function signatures and PostgreSQL switched a couple
> of major versions, but works again in trunk.
> 
> So, did anyone try it ?

Yes, a few years back, but it did not seem to support the use cases I 
was looking at. Use cases:

1. working with polygon coverages to maintain boundary coherence during 
edits
2. simplify adjacent polygons without leaving gaps between them.
3. editing road networks and maintaining coherence of joined segments 
and intersections

While these are more high level application ideas and I guess at the 
lowest level you could build a topology that would support any of these, 
where did not seem to be support for any higher level functions that 
would help support implementing these ideas.

Its been too many cycle since I tried it and my memory is not that clear 
on this any more, but that is what I remember. That said, I think it is 
very cool and would like to see more movement on it, but never found any 
funding possibilities because it seemed like it needed a lot to mature 
it as a product.

Thanks for the fixes to trunk.

-Steve W