His professional contributions spanned subjects as diverse as Functional dependency, object histories, spreadsheet histories, Datalog, and data restructuring.
12.
The determination of functional dependencies is an important part of designing databases in the relational model, and in database normalization and denormalization.
13.
In contrast to the functional dependency, the "'multivalued dependency "'requires that certain tuples be present in a relation.
14.
The notion of logical implication for functional dependencies admits a complete finite axiomatization, known as "'Armstrong's axioms " '.
15.
This functional dependency may suggest that the attribute EngineCapacity be placed in a relation with candidate key VIN . However, that may not always be appropriate.
16.
We denote by F ^ { * } _ { A } the set of all functional dependencies that are derivable from F by inference rules in A.
17.
In other words, its candidate keys do not guarantee that the functional dependency { Person, Shop Type } ?! { Shop } will be respected.
18.
In its simplest application the chase is used for testing whether the relation and " F " is a set of functional dependencies ( FD ).
19.
Unlike in the case of functional dependencies, there is no complete axiomatization for join dependencies, though axiomatization exist for more expressive dependency languages such as full typed dependencies.
20.
A superkey is a property of a relation variable which must hold for all possible values and can only be determined from the functional dependencies which apply to that relation variable.
