18、Entity Relationship (ER) Modeling: Concepts and Practical Applications

Entity Relationship (ER) Modeling: Concepts and Practical Applications

1. Introduction to ER Modeling

Entity Relationship (ER) modeling is a crucial aspect of database design. It helps in visualizing and structuring the relationships between different entities in a database. Let’s start with a practical example where a local city youth league needs a database system to track children signing up for soccer.

1.1 Entities and Attributes

The required entities are Team, Player, Coach, and Parent. Each entity has specific attributes:
| Entity | Attributes |
| ---- | ---- |
| Team | Team ID number, Team name, Team colors |
| Player | Player ID number, Player first name, Player last name, Player age |
| Coach | Coach ID num