Posts with #sql tag

Use PostGIS topologies to clean-up road networks

This article gives a few basics to get started with using the PostGIS topology extension. We will take avandtage of topologies to clean-up a real topological road network, coming from Toulouse...

Drape lines on a DEM with PostGIS

This article gives a few SQL commands to drape 2D geometries on a DEM (Digital Elevation Model), in order to obtain 3D geometries. We use PostGIS 2, and its rasters support especially. Load your...