Practical GIS

Rule-based styling

Road data from OpenStreetMap comes with a classification, which is very useful for creating road maps. This classification is stored in the fclass column in our layer. If we create a categorized symbology based on that column, we can see that there are a lot of classes. From those classes, only a few are appropriate to show at this scale:

Furthermore, some of the classes belong to a single type. For example, the motorway and motorway_link classes distinguish between two subtypes of motorways. QGIS offers a great tool for these cases, called rule-based styling. Let's open the Style tab of our layer's Properties window, and ...