Informix Guide to SQL: Tutorial

Informix Guide to SQL: Tutorial
Chapter 8: Building Your Data Model

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Building Your Data Model

Why Build a Data Model

: Entity-Relationship Data-Model Overview

Identifying and Defining Your Principal Data Objects

Discovering Entities

: Choosing Possible Entities
: Pruning Your List of Entities
: The Telephone-Directory Example
: Diagramming Your Entities

Defining the Relationships

: Connectivity
: Existence Dependency
: Cardinality
: Discovering the Relationships
: Diagramming Your Relationships

Identifying Attributes

: Selecting Attributes for Your Entities
: Listing Your Attributes
: About Entity Occurrences

Diagramming Your Data Objects

: Reading Entity-Relationship Diagrams
: The Telephone-Directory Example

Translating E-R Data Objects into Relational Constructs

Rules for Defining Tables, Rows, and Columns

: Placing Constraints on Columns

Determining Keys for Tables

: Primary Keys
: Foreign Keys (Join Columns)
: Adding Keys to the Telephone-Directory Diagram

Resolving Your Relationships

: Resolving m:n Relationships
: Resolving Other Special Relationships

Normalizing Your Data Model

: First Normal Form
: Second Normal Form
: Third Normal Form
: Summary of Normalization Rules

Informix Guide to SQL: Tutorial, version 9.1
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