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<b>From:</b> Sandro Santilli <strk@kbt.io><br>
<b>Sent:</b> Monday, March 17, 2025 9:34 AM<br>
<b>To:</b> Antonio Valanzano <anvalanz@gmail.com><br>
<b>Cc:</b> postgis-users@lists.osgeo.org <postgis-users@lists.osgeo.org>; Lars Aksel Opsahl <Lars.Opsahl@nibio.no><br>
<b>Subject:</b> Re: PostGIS topology full story</div>
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[2017]<br>
<br>
The Norwegian Institute of Bioeconomy Research (NIBIO) started<br>
contracting me to work on robustness, speed, correctness and new<br>
features for PostGIS Topology.<br>
<br>
The relationship is still ongoing as of 2025.<br>
<br>
> - which are the users that are using the topology for working with tables<br>
> with millions of rows (I am asking this because I have read, but I do not<br>
> remember where, that PostGIS topology is very slow and appropriate only for<br>
> small datasets).<br>
<br>
Surely NIBIO is, I'm adding Lars in Cc so he can tell more.<br>
Regione Toscana did (not sure anymore today)<br>
US Census might be (reading this thread, anyone?)<br>
LINZ - Land Information New Zealand might too (reading this thread anyone from there?)<br>
<br>
Adding a "Use Cases" section for PostGIS Topology would be<br>
great, maybe to be done with a separate thread ...<br>
<br>
--strk;<br>
<br>
Libre GIS consultant/developer</div>
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<a href="https://strk.kbt.io/services.html" id="OWAd60fd2c2-ffb5-4f83-84ba-a54dd3ab2853" class="OWAAutoLink" data-auth="NotApplicable">
https://strk.kbt.io/services.html</a></div>
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<div class="elementToProof" style="font-size: 11pt; color: rgb(102, 102, 102);">Hi</div>
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About Topology, I also heard that rumor many years ago. Maybe my boss also saw that rumor because she told me that if I was able to push AR5 (7 million polygons and corresponding edges) into PostGIS Topology, NIBIO would start to test/use PostGIS Topology.
This was around 10 years ago, and PostGIS Topology has become more and more important for NIBIO as time has gone on.</div>
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We have lately used PostGIS Topology to clean simple feature layers with around 80 million polygons, but it’s not straightforward, that’s true. So we need more work on performance, robustness, and ease of use. We also have a topology edit client that has been
used to edit thousands of faces and edges used by municipalities all over Norway. Without the collaboration with the PostGIS team, especially Sandro, this would not have been possible.</div>
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Most work we do related to PostGIS Topology not found in PostGIS can be found here: https://gitlab.com/nibioopensource</div>
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Lars</div>
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