Switching-algebraic algorithmic derivation of candidate keys in relational databases

Abstract

This paper utilizes concepts and tools of switching algebra to describe an algorithm for computing all candidate keys of a relational database. Our algorithm starts with a superkey comprising all attributes, and then uses logical inference to reduce it to the set of candidate keys. The essential step in this inference is the construction of the complete sum of a pertinent switching function. Some computational saving is possible through the use of Boolean quotients if essential and/or superfluous attributes are recognized.