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Chapter 3 The Relational Model

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Presentation on theme: "Chapter 3 The Relational Model"— Presentation transcript:

1 Chapter 3 The Relational Model
Concepts Properties Keys Relational Integrity Base Relation & View

2 Concepts Relation Attribute Domain Tuple Degree Cardinality
Relational Database Relational Schema

3 Properties Unique relation name Unique attribute No duplication tuples
No repeating group Same domain for an attribute Insignificance of the tuples or attributes order

4 Keys Superkey Candidate key Composite key Primary key Secondary key
Foreign key

5 Relational Integrity Null Types of integrity Types of constraint
Entity Reference Types of constraint Domain (edit or field) Enterprise (business rule)

6 Base Relation & View Base relation View Purpose of views
A named relation of an entity in conceptual schema Tuples stored in physical database View Virtual relation Dynamic generated for end user Not stored in physical database Purpose of views Security User friendly report Performance

7 Assignment Review chapters 1-3 Read Chapter 4 Do Exercise 3.8
Due date:


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