The conversation was all about PostGIS, a geospatial extension to Postgres which just happens to be one the most popular Postgres extensions. This episode was fairly technical, but still fascinating. The discussion ranged all the way from cartesian math at one point to how it’s very difficult to construct a database these days without a location component. This episode of Path To Citus Con focuses on the geospatial world of Postgres and shows how “where” is one of the fundamental things we all want to know about.
In this post, you’ll get a bit of backstory on the topic and the guests—both with a long history with PostGIS—of this episode of Path To Citus Con; and you’ll get a peek at key moments from this show, including the extensibility of Postgres demonstrated by PostGIS, “where” as the universal foreign key, and more. At the end of the post, you’ll find links of where you can listen to this and every episode of the podcast. We hope you love these “human side of Postgres” podcast episodes.
Guests Paul Ramsey (an Executive Engineer for Crunchy Data) and Regina Obe (President of Paragon Corporation)—along with hostsClaire GiordanoandPino de Candia—had a deep conversation about PostGIS, pgRouting, and the geospatial side of Postgres. And there’s also some tangents about Large Language Models in PostGIS as well as how to get started with the extension. Both Regina and Paul have been with PostGIS since its beginning and they describe lots of use cases for PostGIS that go far beyond mapping.
Figure 1: YouTube thumbnail for episode 7 of the Path To Citus Con podcast for developers who love Postgres, with (starting in the top left, listed clockwise) Claire Giordano, Regina Obe, Pino de Candia, and Paul Ramsey. The topic of this episode was “Why people care about PostGIS and Postgres.”
Key quotes & insights from Paul and Regina’s history in PostGIS and Postgres
“‘Where’ is the universal foreign key.”– Regina Obe
Regina talks here about how some developers think of relational databases having hard foreign keys that can easily be joined. But she makes the point that you can also use “where” as a join.
“It's very difficult to build a database that doesn’t have some sort of spatial component to it, even if you're not being explicit about it. You will be modeling objects that exist in the real world and they will have location and you can either not model that location—or you can model it—but if you do model it, PostGIS will help you do it. And [PostGIS] will help you ask and answer questions that otherwise you'd be unable to ask.”– Paul Ramsey
Paul talks about the spatial aspects of databases a lot in this episode. Some of those objects in databases have locations in the real world and how PostGIS can help you do it. It will also help you ask and answer questions that you otherwise couldn’t ask of your model.
“Even though the world is round, we need to model it as flat.”– Regina Obe
Every model in PostGIS has a database and a graph behind it. Regina discusses the four-dimensional space modeled in PostGIS but backed by that same database. Anything that uses Cartesian math can be modeled here, even though it gets “flattened” into a database to do it.
“I tend to say for people who are totally fresh and totally new to the geospatial world, actually start with qgis.org. QGIS is, in many respects, kind of an old school desktop GIS program, but because it's very visual, because it lets you see the maps and understand visually what you're doing it's a wonderful introduction to sort of the spatial gestalt before you get into writing SQL queries that use spatial functions.”– Paul Ramsey
There’s a rich space in GIS that gets discussed in the episode, and QGIS is part of that. As Paul says, it’s a great place to get started if you’re new to the world. He specifically said if you’re completely fresh and new to the geospatial world, you may want to start with QGIS.
“Having a real problem of your own is super important from a motivation point of view. The old “itch to scratch” is really core.”– Paul Ramsey
Getting started with PostGIS is just like getting started with other codebases, and having a problem to solve is the best way to jump into it. Paul and Regina both talk in this episode about how to get started with PostGIS, and Paul specifically suggests you use code to solve those real-world issues you might have.
“People in the Postgres community, like the developer community, care about [PostGIS] because we've been around as a major user of the Postgres core since 2001, before the extension system was even invented. And we have a surprisingly large user community.”– Paul Ramsey
“The reason why PostGIS is important is because it demonstrated to the world how extensible Postgres is.”– Regina Obe
PostGIS is the largest and most popular extension to Postgres. For over 20 years it has shown the power of extensions to Postgres and the communities that can be created around those extensions. Regina talks about her work with the project and coming to a powerful extension from the relational database world.
Where to find the Path To Citus Con podcast episodes (and transcripts)
You can find the transcript for this “Why people care about PostGIS and Postgres” episode with Paul and Regina on the Transcript tab on itsepisode page.
Calendar invite: To be part of the live text chat on Discord that happens in parallel to the live recording (it’s fun),mark your calendar. Don’t stress the details, all the instructions for joining the live show are in the cal invite.