Relational Database Design and Modeling for Software Engineers
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Introduction
Course Overview
Before the Advent of Database
Fundamental Concepts
What is a Database?
Database management systems (DBMS)
Overview of Relational Databases
Relational Vs. Non-Relational Databases
Data Modeling
Introduction to Data Modeling
Levels of Data Modeling
Data Modeling Process
Best Practices in Data Modeling
Quiz
Entity-Relationship (ER) Data Modeling
Introduction to ER Models
Entities, Attributes, and Relationships
Cardinality and Participation
Attributes of Relationship Types
Weak Entity Types
Creating an ER Diagram for Employee Management System
Quiz
Introduction to the Relational Model
Relations, Tuples, and Attributes
Keys in Relational Databases
Relational Integrity Constraints
Converting ER Diagrams to Relational Model
Best Practices for ER Diagrams to Relational Models
Quiz
Introduction to Functional Dependency
Types of Functional Dependencies
Inference Rules for Functional Dependencies
Closure of Attribute Sets
Quiz
Introduction to Normalization
First Normal Form (1NF)
Second Normal Form (2NF)
Third Normal Form (3NF)
Boyce-Codd Normal Form (BCNF)
Higher Normal Forms (4NF, 5NF)
Exercise 1
Solution to Exercise 1
Exercise 2
Solution to Exercise 2
Designing a Hospital Management System
Designing a Hotel Management System
Designing a Bank Management System
Designing an Instagram
Designing an E-commerce Platform
Designing an Online Food Delivery System
Attributes of Relationship Types

In ER models, relationships between entities can have attributes of their own, known as attributes of relationship types. These attributes provide additional information about the association between entities. They are especially useful in cases where details about the relationship itself are essential to the database structure and cannot be fully represented by entity attributes alone.

Understanding Relationship Attributes

Relationship attributes store properties specific to the interaction between two or more entities, rather than to the entities themselves. These attributes are typically included when the relationship has properties that need to be tracked independently from the entities involved.

  • Example: In an academic database, the relationship between Student and Course is "enrolls in." This relationship could have attributes such as Enrollment Date and Grade.

Examples of Relationship Attributes

  1. Enrollment Example:
    • Entities: Student and Course
    • Relationship: "Enrolls in"
    • Attribute of Relationship:

      • Enrollment Date: The date when the student enrolled in the course.

    Here, Enrollment Date is not specific to the Student or Course entities individually but rather describe the association between them.
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  1. Employment Example:

    • Entities: Employee and Department
    • Relationship: "Works in"
    • Attributes of Relationship:
      • Position: The role or title the employee holds in that department.

    In this case, Position is detail about the relationship "works in" between Employee and Department, not attributes of the Employee or Department entities alone.

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Cardinality and Participation
Weak Entity Types
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Understanding Relationship Attributes

Examples of Relationship Attributes