PostGIS topology full story

[Sandro Santilli]

On Sun, Feb 09, 2025 at 10:02:54AM +0100, Antonio Valanzano wrote:
> Dear list members
> does someone know where I can read the full story of PostGIS topology ?
> 
> I am interested in knowing:
> - who developed it and when this development started

I started development in October 2005, see commit 2b5868ca90
online at https://git.osgeo.org/gitea/postgis/postgis/commit/2b5868ca

> - which have been the mayor releases and improvements during the years

[2005]

Initial development was funded by Refractions Research.

[2006]

I first presented PostGIS Topology in Lausanne (FOSS4G 2006). Slides here:
https://strk.kbt.io/projects/postgis/FOSS4G2006_FutureDevelopmentOfPostGIS.pdf

At that time the code was considered an "extra", and you can still see
reminescences of that in the PostGIS User Manual source filename:
https://git.osgeo.org/gitea/postgis/postgis/src/branch/master/doc/extras_topology.xml

[2011]

Regione Toscana funded completion of SQL/MM function signatures
https://strk.kbt.io/blog/2011/10/14/postgis-topology-iso-sqlmm-complete/

[2012]

A geometry importer (toTopoGeom) was funded by a public fundraising:
https://lists.osgeo.org/pipermail/postgis-users/2012-January/032055.html

[2016]

Topology functionality was moved down from plpgsql to C as part of a
project to reuse the code in other databases (librrtopo was born).
This was again funded by Regione Toscana.

[2017]

The Norwegian Institute of Bioeconomy Research (NIBIO) started
contracting me to work on robustness, speed, correctness and new
features for PostGIS Topology.

The relationship is still ongoing as of 2025.

> - which are the users that are using the topology for working with tables
> with millions of rows (I am asking this because I have read, but I do not
> remember where, that PostGIS topology is very slow and appropriate only for
> small datasets).

Surely NIBIO is, I'm adding Lars in Cc so he can tell more.
Regione Toscana did (not sure anymore today)
US Census might be (reading this thread, anyone?)
LINZ - Land Information New Zealand might too (reading this thread anyone from there?)

Adding a "Use Cases" section for PostGIS Topology would be
great, maybe to be done with a separate thread ...

--strk;

  Libre GIS consultant/developer
  https://strk.kbt.io/services.html