I flew home from St. Louis yesterday, returning from the FOSS4G North America conference. I took a different approach to the conference this year than I did in 2023. Rather than moderate sessions and participate in a lot of on-site logistics, I sat in on more sessions so I got to see a lot more … Continue reading A FOSS4GNA Savasana
Tag: PostgreSQL
Producing GeoJSON with SQL
A couple of weeks ago, I had a need to return GeoJSON from PostGIS. This is something I've done many times, but I usually do the final formatting in the application/API layer with Javascript or Python. Basically, my workflow has been to SELECT, using the built-in ST_AsGeoJSON function to convert the geometry to GeoJSON. I … Continue reading Producing GeoJSON with SQL
Using pg_webhooks with n8n – A Simple Example
I've been integrating pg_webhooks into some project work lately. Conversely, I have not been using n8n much, but a vendor rep used it in a demo of some workflow automation capabilities for a platform one of my customers is using. I had dabbled with it about two years ago but haven't done much with it … Continue reading Using pg_webhooks with n8n – A Simple Example
Window Functions and PostGIS
FOSS4G North America was an opportunity for me to reconnect with both community and technology. I enjoyed being able to both learn new things and refresh my skills with technologies such as PostGIS. I was reflecting on how, a couple weeks prior to the conference, I introduced the concept of PostgreSQL window functions to a … Continue reading Window Functions and PostGIS
A Few Updates to pg_webhooks
At the time of my last post, there were a few outstanding issues that I wanted to address in the code of pg_webhooks. I've addressed three of them this week. There wasn't actually a route to unsubscribe from a channel, so I added that shortly after the initial release. Another key shortcoming was that the … Continue reading A Few Updates to pg_webhooks
A Simple Webhook Interface for PostgreSQL NOTIFY
PostgreSQL's NOTIFY/LISTEN method for subscribing to events from a database is a subject I return to periodically. I've touched on it in one form or another over several years. My latest run at it involves building a Node Express application that will allow external systems to subscribe to webhooks that are fired by NOTIFY statements … Continue reading A Simple Webhook Interface for PostgreSQL NOTIFY
Analyzing Location Change Over Time in PostGIS
Following up on my previous post, I decided to attempt the same analysis in PostgreSQL. The analysis doesn't make use of any spatial logic itself (yet), but I consider this a PostGIS post because it is using PostGIS geometries. In the past, I have noticed that BigQuery SQL is very reminiscent of that of PostgreSQL, … Continue reading Analyzing Location Change Over Time in PostGIS
Attribute Transfer in PostGIS Using Spatial SQL
Data conflation is a meat-and-potatoes task in most GIS workflows. There are numerous reasons one might need to get data from one data set into another. Perhaps you want to attach a new geometry type to existing attributes or a table. Or maybe you need to pull attributes from one or more data sets into … Continue reading Attribute Transfer in PostGIS Using Spatial SQL