Regina Obe from Paragon Corporation presents at PostGIS Day 2021. PostGIS packages six different extensions and there are many others that further extend PostGIS like pgrouting, mobilitydb and ogr_fdw. Regina shows off the postgis_topology tool and she has a nice overview of a sql with geometric output in the form of letters.

Slides HTML: https://postgis.us/presentations/PostGISDay2021_PostGISExtensions.html

Slides PDF: https://postgis.us/presentations/PostGISDay2021_PostGISExtensions.pdf

Code: https://postgis.us/presentations/postgis_day_2021.sql Screen reader support enabled.