Overview

PostGIS is an extension that adds support for geographic objects to PostgreSQL. You can store points, lines and polygons, and run spatial queries such as "which shops are within 2 km of this location?".

It is the foundation of many GIS and mapping applications and works with tools like QGIS, GeoServer and web map libraries.

Where it is used

• Store locators and delivery apps
• Fleet and asset tracking
• Land, utility and city mapping
• Environmental and agricultural analysis

Enable PostGIS

docker run --name postgis -e POSTGRES_PASSWORD=change-me -p 5432:5432 -d postgis/postgis

-- inside the database:
CREATE EXTENSION postgis;

SELECT name
FROM shops
WHERE ST_DWithin(location::geography,
                 ST_MakePoint(77.5946, 12.9716)::geography,
                 2000);