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Database Management Systems/Managing Database Pooja Gupta, Lovely Professional University

Notes Unit 2: Database Relational Model

CONTENTS
Objectives
Introduction

2.1 Relational Model
2.1.1 Relational Model Concepts
2.1.2 Alternatives to the Relational Model

2.1.3 Implementation
2.1.4 Application to Databases
2.1.5 SQL and the Relational Model
2.1.6 Set-theoretic Formulation
2.2 Additional and Extended Relational Algebra Operations

2.2.1 Relational Algebra Expression
2.2.2 Set Operation of Relational Algebra
2.2.3 Joins

2.3 Summary
2.4 Keywords
2.5 Self Assessment
2.6 Review Questions
2.7 Further Readings

Objectives

After studying this unit, you will be able to:
 Describe relational model

 Explain additional and extended relational algebra operations
Introduction

A relational database consists of a collection of tables that store particular sets of data. The
invention of this database system has standardized the way that data is stored and processed.
The concept of a relational database derives from the principles of relational algebra, realized as
a whole by the father of relational databases, E. F. Codd. Most of the database systems in use
today are based on the relational system.
2.1 Relational Model

The relational model for database management is a database model based on first-order predicate
logic, first formulated and proposed in 1969 by Edgar Codd.

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