I've got a shape file that I loaded into PostGIS that has both road and parcel multipolygons and I need to remove the roads. I tried loading the shp file in qgis and it loads them both as a single layer. I need to remove roads as best I can without removing parcels. I can remove most of them by testing whether the address is equal to null. However this deletes parcels where that data is unavailable.
My idea is to create another filter that tests the complexity of the geometry since most roads are complex polygons and parcels are generally simple (not all). Then I think I will find a "close enough" solution where most roads are removed, and little to no parcels are removed.
Here is what I've looked at to no avial:
st_isSimple : tests whether a polygon is anomalous (self intersection or tangent)
st_numPoints : Does not work because it only looks at the first linestring and there are no linestrings
Anyway, what ideas do you have for classifying a polygon as a road? Is there a query I can do? A feature I can extract offline?