Practical GIS

Filtering layers

The filtering dialogue can be accessed by right-clicking on a layer in the Layers Panel and selecting Filter. As we can see in the dialogue, filtering expressions are much more restrictive in QGIS as they only allow us to write basic SQL queries with the fields of the layer. Let's inspect our study area in the administrative boundaries layer with the Identify Features tool, select a unique value like its name, and create a query selecting it. For me, the query looks like the following:

    "NAME_1" = 'Baranya'

Applying the filter removes every feature from the canvas other than our study area:

Now the only feature showing up ...