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Entities and attributes

Entities and Attributes Home

What its about

Theory

Introduction

1. Introduction

entities

attributes

database relationships

4. Database relationships

entity relationship diagrams

5. E-R Diagrams

one-to-one relationship

6. One-to-one relationships

one-to-many relationshipF

7. One-to-many relationships

many-to-many relationship

8. Many-to-many relationships

changing many to many relationships

9. Changing many-to-many

desgining relationships

10. Designing relationships

7. One-to-many (or many-to-one) relationships

Example of a one-to-many relationship

Think about a mother and her children.

A mother can have many children

A child can have only one mother

this would be known as a 'one-to-many relationship'

This relationship can be portrayed diagramatically as:

one to many relationship

challenge see if you can find out one extra fact on this topic that we haven't already told you

Click on this link: Compound primary keys