Chapter 4

Entities and Relationships

Abstract

This chapter discusses data modeling independent of any specific theoretical data model. Topics include entities, attributes, using entity-relationship diagrams to represent entities and their attributes, domains, data relationships, representing data relationships in entity-relationship diagrams (three styles of diagramming), and handling many-to-many relationships using composite entities.

Keywords

entity
entity relationship diagram
database column domains
database attributes
database relationships
one-to-one relationships
one-to-many relationships
many-to-many relationships
weak entities
mandatory relationships
composite entities
data modeling
data flow
In this chapter, we will look at the basis for ...

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