Pgrouting- A Practical Guide May 2026

Introduction In the world of Geographic Information Systems (GIS), routing and network analysis are critical for applications ranging from GPS navigation to urban planning. While desktop tools like QGIS or ArcGIS offer routing capabilities, they often struggle with large datasets or real-time queries. This is where pgRouting —an extension of PostgreSQL and PostGIS —becomes an indispensable solution.

SELECT * FROM pgr_drivingDistance( 'SELECT gid AS id, source, target, cost FROM roads', 1, -- start vertex 500, -- distance limit false -- undirected ); SELECT * FROM pgr_astar( 'SELECT gid AS id, source, target, cost, reverse_cost, x1, y1, x2, y2 FROM roads', 1, 50, true ); Note : A* requires columns x1, y1, x2, y2 (endpoint coordinates). Add them using: PgRouting- A Practical Guide

SELECT * FROM pgr_dijkstra( 'SELECT gid AS id, source, target, cost, reverse_cost FROM roads', 1, -- start vertex 50, -- end vertex directed := true ); : A set of rows with node , edge , cost , and agg_cost (total cost). b) Get the geometry of the path Join the results back to the geometry table: Introduction In the world of Geographic Information Systems