LOGICAL DATABASE DESIGN pptx

2A.1 Relational Database Design

LESSON: 2A

LOGICAL DATABASE DESIGN

Objectives

In this lesson, you will learn to:

 Map an E/R Diagram to Tables in relation to the following:

x Regular entities

x Attributes

x Relationships

x Weak entities

x Subtypes and supertypes

 Identify keys

 Define Specialization and Generalization

Relational Database Design 2A.2

©NIIT Logical Database Design Lesson 2A / Slide 1 of 15

Logical Database Design

Objectives

In this section, you will learn to:

• Map an E/R diagram to tables in relation to the following:

• Regular entities

• Attributes

• Relationships

• Weak entities

• Subtypes and supertypes

• Identify keys

• Define Specialization and Generalization

INSTRUCTOR NOTES

Lesson Overview

The lesson introduces the concept of mapping E/R diagrams to tables with respect to

regular entities, weak entities, relationships, attributes, subtypes, and supertypes.

This lesson also contains tips for logical database design and covers the various types

of keys and their applications. In addition, this lesson explains specialization and

generalization of entities.

2A.3 Relational Database Design

©NIIT Logical Database Design Lesson 2A / Slide 2 of 15

Logical Database Design

Pre-assessment Questions

1. In an E/R diagram, an entity is represented as a ______.

a. Diamond

b. Line

c. Box

d. Oval

2. Which of the following denotes an association between entity types?

a. Relation

b. Relationship

c. Relationship type

d. Relation type

3. Which data model has the database structured in fixed-format records of several

types?

a. Relational model

b. Object-based logical model

c. Network model

d. Hierarchical model