convert_to_triples ::
  student(S,D,A,Y) ==>
    student.major(S,D) &
    student.advisor(S,A) &
    student.year(S,Y)

convert_to_triples ::
  student(S,D,A,Y) ==> ~student(S,D,A,Y)



convert_to_tables ::
  student.major(S,D) &
  student.advisor(S,A) &
  student.year(S,Y) ==>
    student(S,D,A,Y)

convert_to_tables ::
  student.major(S,D) ==> ~student.major(S,D)

convert_to_tables ::
  student.advisor(S,D) ==>
    ~student.advisor(S,D)

convert_to_tables ::
  student.year(S,D) ==> ~student.year(S,D)