To formulate my question with a concrete example: I have two multi-polygon layers of the same city.
- Layer A has polygons of the city divided in parts e.g. north, south, west, east.
- Layer B has smaller polygons that represent green e.g. trees, forests, parks and such.
Now I want to add a new column "city_part" in the attribute table of layer B. And likewise I'd want an either QGIS-expression- or Python-coded script, that can figure out in which polygon of layer A every single polygon of layer B lies. So the concrete result would be a layer B in which every polygon's got a new attribute, telling whether it resides inside north, south, west or east. How can this be done?