Select ONE organization For your project
Identify the entities and their attributes
Identify the degree of their relationship
Identify their cardinalities
Organization: Apple Inc.
Entities and their attributes:
1. Employees
- Employee ID (PK)
- Name
- Department
- Salary
- Position
2. Products
- Product ID (PK)
- Name
- Description
- Price
- Category
3. Customers
- Customer ID (PK)
- Name
- Address
- Email
- Phone number
Degree of relationships:
1. Employees can work on multiple products.
2. Products can be worked on by multiple employees.
3. Customers can purchase multiple products.
4. Products can be purchased by multiple customers.
Cardinalities:
1. Employees (1) ----- (0 or more) Products
- One employee can work on zero or more products.
- A product can have one or more employees working on it.
2. Products (1) ----- (0 or more) Employees
- One product can be worked on by zero or more employees.
- An employee can work on one or more products.
3. Customers (0 or more) ----- (0 or more) Products
- A customer can purchase zero or more products.
- A product can be purchased by zero or more customers.
4. Products (0 or more) ----- (0 or more) Customers
- A product can be purchased by zero or more customers.
- A customer can purchase zero or more products.
One organization that can be selected for this project is a university.
Entities and their attributes:
1. Student
- Student ID
- Name
- Age
- Gender
- Major
- GPA
2. Faculty
- Faculty ID
- Name
- Age
- Gender
- Department
3. Course
- Course ID
- Title
- Credits
- Department
4. Department
- Department ID
- Name
- Location
Degree of their relationship:
1. Student-Faculty Relationship: A student can have a relationship with multiple faculty members, and a faculty member can have a relationship with multiple students. This is a many-to-many relationship.
2. Student-Course Relationship: A student can be enrolled in multiple courses, and a course can have multiple students enrolled. This is a many-to-many relationship.
3. Course-Faculty Relationship: A course can be taught by multiple faculty members, and a faculty member can teach multiple courses. This is also a many-to-many relationship.
4. Department-Faculty Relationship: A department can have multiple faculty members, but a faculty member can only belong to one department. This is a one-to-many relationship.
Cardinalities:
1. Student-Faculty Relationship: The cardinality is many-to-many.
2. Student-Course Relationship: The cardinality is many-to-many.
3. Course-Faculty Relationship: The cardinality is many-to-many.
4. Department-Faculty Relationship: The cardinality is one-to-many.
To answer these questions, I will guide you through the process of selecting an organization, identifying its entities and their attributes, determining the degree of their relationship, and finally identifying their cardinalities.
Step 1: Select an Organization
Choose an organization that you are familiar with or interested in studying for your project. Some examples include a university, a retail store, a hospital, or a bank.
Step 2: Identify Entities and Their Attributes
Entities are the objects or concepts within an organization that we want to store information about. Start by listing the main entities relevant to your chosen organization. For example, if you have selected a university, some entities might include students, courses, professors, and departments.
Next, identify the attributes for each entity. Attributes are the properties or characteristics that describe an entity. Continuing with the university example, attributes for the student entity could include student ID, name, date of birth, and major. For the course entity, attributes might include course code, title, description, and credit hours.
Step 3: Identify the Degree of Their Relationship
Once you have identified the entities and their attributes, consider the relationships between these entities. Determine the degree of their relationship, which refers to the number of entities involved in that relationship. The three most common degrees of relationships are:
- One-to-One (1:1): Each entity in one set corresponds to exactly one entity in the other set. For example, in a university setting, a student can have only one student ID, and a student ID is assigned to only one student.
- One-to-Many (1:N): Each entity in one set can have multiple corresponding entities in the other set, but each entity in the other set can only be related to one entity in the first set. For instance, in a university, a department can have multiple professors, but each professor can only be affiliated with one department.
- Many-to-Many (M:N): Multiple entities in both sets can be related to multiple entities in the other set. This type of relationship often requires an intermediate table or entity. For example, in a university, a student can enroll in multiple courses, and a course can have multiple students.
Step 4: Identify Their Cardinalities
Cardinality refers to the number of instances of one entity that can be associated with the number of instances of another entity. In other words, it indicates the minimum and maximum number of related entities in a relationship. Cardinality is typically denoted as a pair of numbers in notation like (1,1), (1,N), or (M,N) to represent the minimum and maximum cardinalities for each entity involved.
For example, in the one-to-many relationship between a student and a department in a university, the student (N) can be related to only one department (1), whereas the department (1) can have multiple students (N).
By following these steps and applying them to the organization you have selected, you will be able to identify the entities, attributes, degree of relationships, and cardinalities involved.