[postgis-devel] topology.sql distribution

[strk]

On Thu, Jul 08, 2010 at 10:26:50AM +0100, Mark Cave-Ayland wrote:

> However I think the following issues need to be resolved before we can 
> consider this:
> 
> i) Access to a specification (and no, I don't see paying for the 
> specification as a valid option). Perhaps there are free drafts 
> available, much like SQL/MM?

Version 1 (2004) and 2 (2005) seems available:
http://wiscorp.com/H2-2004-168r2-Topo-Geo-and-Topo-Net-1-The-Concepts.pdf
http://www.wiscorp.com/H2-2005-107r2-Topo-Concepts-The-Sequel.pdf

I belive draft version 3 is the one which ended up in the standard.
Not sure if that one is public.

> ii) Creating documentation for the PostGIS manual. I don't see how 
> anyone can use it at the moment since it is entirely undocumented. We 
> should probably mark it as beta quality too.

topology/README should be pretty much complete in describing what's
currently available. IIRC the postgis wiki should contain some more pages.

> iii) Maintenance. Who will be responsible for maintaining this part of 
> the code longer term?

I'm willing to take this.

> Also, do TopoGeometries required their own PostgreSQL type in the longer 
> term? Or is the specification simply a set of tables and joins?

There's a PostgreSQL type defined by SQL (TopoGeometry).
A factory function for it was in the standard:
   Topo-Geo and Topo-Net 3: Routine Details
   X.3.18(ST_CreateTopoGeo)

What was in the standard and what not seems to be documented in the
SQL file itself for each function/block (topology/topology.sql.in.c)

--strk;

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