Willem Booysen
postgresconf.org/conferences/...
Window Functions are easy...ish once you understand the syntax and how one needs to approach your data.
The second South African PostgresConf takes place in Johannesburg on 9 October 2018, with attendees representing a diverse class of professionals and companies from around the country and across the continent. This is an excellent opportunity for the database administration and developer community who use PostgreSQL to get to know each other, exchange ideas and learn about the current features and upcoming trends within PostgreSQL.
Code available at: gist.github.com/IllusiveMilkm...