Volume 4
Volume 4, Number 7 |
February 13, 2006 |
Abstract: Functional dependencies are merely a type of relationship between attributes in a relation, or, alternatively, may be viewed as constraints on attributes, but their importance in the optimal design of databases is enormous. Normalization of a database, and the decomposition of relations, are totally dependent upon the database designer being able to identify functional dependencies, and manipulate them. Curricula in CS, IS and IT will almost always include a course in database design, with functional dependencies being a key topic in such a course. FD-Explorer is a new tool we have developed which enables both the student of database design, as well as professional database developers, to define a known set of functional dependencies on a relation, deduce new sets of functional dependencies, compute closures of individual attributes and the set of functional dependencies, and identify superkeys. This software tool, which we ultimately intend to make freely available for students in database design classes in institutions of higher learning, will provide the user with significant insight into the underlying explicit and implicit relationships between attributes, contribute to the optimal design of database structures in applications, and enhance the user’s understanding of the fundamental principles of functional dependencies.
Keywords: functional dependencies, database design, Armstrong’s axioms, normalization, attributes, closure
Download this issue: ISEDJ.4(7).Scher.pdf (Adobe PDF, 9 pages, 785 K bytes)
Preview the contents: Scher.v1.txt (ASCII txt, 21 K bytes)
Recommended Citation: Scher and Qiu (2006). FD-EXPLORER: A Pedagogical and Design Tool for Functional Dependency Exploration. Information Systems Education Journal, 4 (7). http://isedj.org/4/7/. ISSN: 1545-679X. (A preliminary version appears in The Proceedings of ISECON 2004: §4123. ISSN: 1542-7382.)