As a Database Specialist you are required to analyse a private school current database system.
Using the business rules provided below create an Entity-Relationship Diagram (ERD) using Unified
Modelling Language.
HINT: Show all the relationships and notations.
A teacher may teach a maximum of three subjects and the teacher can teach at least 30
students;
A specific course can include many subjects;
A subject can only be delivered in one classroom at a time, but a classroom may be
scheduled for more than one subject; and
A student can take a maximum of four subject as school policy.
Here is an Entity-Relationship Diagram (ERD) for the private school database system based on the provided business rules:
Entities:
- Teacher
- Subject
- Student
- Classroom
- Course
Relationships:
- Teacher teaches Subject (1 to 3 relationship)
- Teacher teaches Students (1 to many relationship)
- Course includes Subject (1 to many relationship)
- Subject delivered in Classroom (1 to 1 relationship)
- Classroom scheduled for Subject (1 to many relationship)
- Student takes Subject (1 to 4 relationship)
Notations:
- Teacher:
- attributes: teacher_id (PK), teacher_name
- Subject:
- attributes: subject_id (PK), subject_name
- Student:
- attributes: student_id (PK), student_name
- Classroom:
- attributes: classroom_id (PK), classroom_location
- Course:
- attributes: course_id (PK), course_name
Please note that relationships between entities are shown with lines connecting the entities and the cardinality of each relationship is denoted on the line.