In any relation,
attribute A is
||Example of rule violation
||A relation cannot have repeating fields or groups.
||<author(1), author(2)..., title>
every nonkey field must be functionally dependent
on all of the key.
||<part, warehouse, quantity, warehouse-address>
where the key is "part", "warehouse"
a nonkey field cannot be functionally dependent
on another nonkey field.
||<employee, department, department-location>
where the key is "employee"
||A relation cannot contain two or more
independent multivalued attributes of an entity
||<employee, skill, language>
where the key is "employee", "skill",
||Roughly, a relation cannot be reconstructed
from several relations each having fewer fields
and not all having the same key
||<salesperson, product, client>
where it is known that, if a salesperson sells a product
and sells to a client,
then that salesperson sells that product to that client