relation	movies
file	movies.arff
key	id_movie

relation	nation
file	nation.arff
key	n_nationkey
foreign 	n_regionkey:region:r_regionkey

relation	ratings
file	ratings.arff
foreign 	id_movie:movies:id_movie
foreign 	id_user:users:userid

relation	region
file	region.arff
key	r_regionkey

relation	users
file	users_occupation_training.arff
key	userid
class	class
foreign 	nation:nation:n_nationkey

