Is Fox Pro dbms or rdbms and why?

every rdbms is a dbms.as of a standard there is a criteria for any prog. lang. to become rdbms. this is defined in codds 12 rules. this all together if satisfied then any prog lang can be said to be a rdbms. but in practice we come across many examples where a prog lang is not rdbms but still provide relational database very often. ex foxpro is not rdbms because it does not satisfy one of the codds 12 rule i.e. of defining a foreign key. in foxpro you cannot define a foreign key. but since it has tables in it and can provide relations we can term foxpro as pseudo rdbms(partial rdbms)..........