text: -- fetch geometry for city from osm_admin
  ALTER TABLE public.osm_struct_cities ADD COLUMN geometry gis.geometry(geometry, 3857);
  
  UPDATE public.osm_struct_cities c SET geometry = p.geometry
  	FROM public.osm_postal_code p
  	WHERE
  		c.geometry IS NULL
  		AND p.postcode = c.postcode
  		AND gis.ST_Intersects(c.extent, gis.ST_SetSRID(gis.Box2D(p.geometry), 3857));
  
  UPDATE public.osm_struct_cities c SET geometry = a.geometry
  	FROM public.osm_admin a
  	WHERE
  		c.geometry IS NULL
  		AND a.name = c.name
  		AND a.admin_level = 8
  		AND gis.ST_Intersects(c.extent, gis.ST_SetSRID(gis.Box2D(a.geometry), 3857));