[postgis-users] Open-ended (and slightly amateurish) topology question

[Webb Sprague]

Hi list, please forgive my both my top-quoting and my ignorance ...

... but could someone describe the canonical use-cases of GIS
topology, especially within the context of PostGIS (ie at the psql
prompt)?  Or a canonical set of abstract data structures to represent
a topology?  A detailed example?

Would "a topology" be mostly useful for enforcing geographic
constraints when editing and inserting?  Doing quick adjacency
queries?  Routing?  Modifying  a geography? How?

(It seems to me there should be a schema attached to the main db to
hold topology information in parallel, with triggers and functions to
keep them in sync or throw "topology violation errors" as appropriate,
but I don't really know what I am talking about....)

If there is a reference somewhere, or a way to play with topology in a
free GIS, please share...

Thx!

On Dec 3, 2007 5:09 PM, Cofundos.org <list at cofundos.org> wrote:
> Hi all,
>
> The following PostGIS related project was created on Cofundos.org (a platform for describing open-source project ideas and pooling resources for their implementation):
>
> *Topology Support for PostGIS* by sdteffen
> Tags: Database GIS PostGIS PostgreSQL topology
> http://Cofundos.org/project.php?id=46
>
> Project description: PostGIS spatially enables the PostgreSQL database (it adds GIS functionality).
> While PostGIS is very powerful already, topology support is still lacking.
> Kevin Neufeld summarizes the current state on the postgis mailing list:
>
> http://postgis.refractions.net/pipermail/postgis-users/2007-October/017532.html
>
> I would be primarily interested in network topology support (line/node structure to
> support modeling of water/wastewater networks), but other users might look for
> a more comprehensive solution (including polygon topology).
>
> More info at: http://Cofundos.org/project.php?id=46
>
> You can support this project by commenting it or bidding for its impementation!
>
>
> --
> 241 Cofundos users were placing 133 bids (amounting Euro 6185) on 67 projects.
>
> *Please help making open-source even more successful*
> Spread the word about http://Cofundos.org
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