pot_del_country(N,C,Cap,CapP,A,Pop) :- ext_del_country(N,C,Cap,CapP,A,Pop), country(N,C,Cap,CapP,A,Pop). % Province(Country) refs Country(code) on delete cascade pot_del_province(P,C,PPop,PA,PCap,PCapProv) :- pot_del_country(N,C,Cap,CapP,A,Pop), province(P,C,PPop,PA,PCap,PCapProv). % City(Country) refs Country(code) on delete cascade pot_del_city(CN,C,P,CPop,Long,Lat,El) :- pot_del_country(N,C,Cap,CapP,A,Pop), city(CN,C,P,CPop,Long,Lat,El). % City(Country,Province) refs Province(name,country) on delete no action <<<<<<<< blk_del_province(P,C,PPop,PA,PCap,PCapProv) :- pot_del_province(P,C,PPop,PA,PCap,PCapProv), city(CN,C,P,CPop,Long,Lat,El), rem_city(CN,C,P,CPop,Long,Lat,El). rem_city(CN,C,P,CPop,Long,Lat,El) :- city(CN,C,P,CPop,Long,Lat,El), not del_city(CN,C,P,CPop,Long,Lat,El).