Chapter 9 - Relations

Abstract

There are many forms of relations. Relations from many basic aspects are discussed in this chapter. First, relations on sets and their properties are discussed. Tables, arrow diagrams, digraphs, and zero-one matrices as methods to represent relations are introduced. Operations on relations, including union, intersection, difference, and composition, are detailed. Closure properties, equivalence relations, equivalence class, and representative are discussed. The focus then turns toward partial orderings and linear order relations. Finally, some elementary features of relational databases are discussed.