We prove normal form theorems of a complete axiom system for the inference of functional dependencies and independencies in relational databases. We also show that all proofs in our system have a normal form where the application of independency rules is limited to three levels. Our normal form results in a faster proof-search engine in deriving consequences of functional independencies. As a result, we get a new construction of an Armstrong relation for a given set of functional dependencies. It is also shown that an Armstrong relation for a set of functional dependencies and independencies do not exist in general, and this generalizes the same result valid under the closed-world assumption.
Bibliographical noteFunding Information:
This work was partially supported by DoD MURI grant DAAH04-96-10341. ∗Corresponding author. E-mail addresses: firstname.lastname@example.org (D. Wijesekera), email@example.com firstname.lastname@example.org (J. Srivastava), email@example.com (A. Nerode).
- Completeness proofs
- Data mining
- Functional dependencies
- Integrity constraints