ABSTRACT
The most incomprehensible thing about the world is that it is comprehensible.
—Albert Einstein
2.1 Entity and Relationship Type Object Sets .................................... 37 2.2 Attributes and Surrogate Keys ..................................................... 38 2.3 Entity-Relationship Diagrams (E-RDs) ....................................... 40 2.4 Functional Relationships and the Key Propagation
Principle (KPP) ............................................................................ 42 2.5 Relationship Hierarchies .............................................................. 44 2.6 Higher Arity Non-Functional Relationships ................................ 48 2.7 Restriction Sets ............................................................................ 49 2.8 Case Study: A Public Library (Do We Know Exactly
What a Book Is?) ......................................................................... 60 2.9 The Algorithm for Assisting the Data Analysis and Modeling
Process (A0): An E-R Data Model of the E-RDM....................... 69 2.10 Best Practice Rules ...................................................................... 75 2.11 The Math Behind E-RDs and Restriction Sets-The Danger
of “Many-To-Many Relationships” and the Correct E-RD of E-RDM..................................................................................... 92
2.12 Conclusion ................................................................................... 98 2.13 Exercises ...................................................................................... 99 2.14 Past and Present ..........................................................................110 Keywords ...............................................................................................111 References ..............................................................................................112
