Posts about Spatial

At PostGIS Day 2023, one of our speakers showed off a really cool demo for getting JSON and SVGs in and out of Postgres / PostGIS and into Google Sheets. Brian Timoney put together several open source projects in such a cool way that I just had to try it myself. If you want to see his demo video, it is on YouTube

We hosted our annual PostGIS day a couple weeks ago with some great talks on a big variety of topics within open-source GIS. Here is a summary of the themes I saw take shape across the day’s events that will point you towards the recordings, depending on your interests. A full playlist of PostGIS Day 2023

A user on the postgis-users had an interesting question today: how to generate a geometry column in PostGIS with random points, linestrings, or polygons?

Random data is important for validating processing chains, analyses and reports. The best way to test a process is to feed it inputs!

Random Points

PostGIS excels at storing, manipulating and analyzing geospatial data. At some point it's usually desired to convert raw spatial data into a two-dimensional representation to utilize the integrative capabilities of the human visual cortex. In other words, to see things on a map.

PostGIS is a popular backend for mapping technology, so there are many options to choose from to create maps. Data can be rendered to a raster image using a web map server like GeoServer

Geocoding is the process of taking addresses or location information and getting the coordinates for that location. Anytime you route a new location or look up a zip code, the back end is geocoding the location and then using the geocode inside other PostGIS functions to give you the routes, locations, and other data you asked for.

PostGIS comes equipped with an easy way to use the US Census data with the Tiger geocoder

In geospatial terminology, a "raster" is a cover of an area divided into a uniform gridding, with one or more values assigned to each grid cell.

A "raster" in which the values are associated with red, green and blue bands might be a visual image. The rasters that come off the Landsat 7

In a previous post we announced the CQL filtering capability in pg_featureserv. It provides powerful functionality for attribute and spatial

Working at Crunchy Data on the spatial team, I'm always looking for new features and fun things to show on live demos. I recently started playing around with ST_Letters and wanted to jot down some quick code samples for playing around with this feature, introduced in PostGIS 3.3. These examples are super easy to use, they don't need any data!

The screenshots shown below came from pgAdmin's geometry viewer and will also work with other query GUI tools like QGIS or DBeaver.

ST_Letters

Imagine your system captures event data from all over the world but the data all comes in UTC time giving no information about the local timing of an event. How can we quickly convert between the UTC timestamp and local time zone using GPS location? We can quickly solve this problem using PostgreSQL and PostGIS.

This example assumes you have a Postgres database running with PostGIS. If you’re new to PostGIS, see PostGIS for Newbies