Database Design and Relational Theory: Normal Forms and All That Jazz

© C. J. Date 2019

C. J. DateDatabase Design and Relational Theoryhttps://doi.org/10.1007/978-1-4842-5540-7_4

4. FDs and BCNF (Informal)

C. J. Date¹ 

(1)

Healdsburg, California, USA

 

It is downright sinful to teach the abstract before the concrete.

—Z. A. Melzak: Companion to Concrete Mathematics (1973)

As noted in the previous chapter, Boyce/Codd normal form (BCNF for short) is defined in terms of functional dependencies (FDs); indeed, it’s really the normal form with respect to functional dependencies, just as—to get ahead of ourselves for a moment—5NF is really the normal form with respect to join dependencies (JDs). The overall purpose of the present chapter is to explain BCNF and FDs in detail; as the chapter title indicates, however, the various ...