Question

Draw an EER model of given scenario

We wish to create a database for a company that runs training courses. For this, we must store data about the trainees and the instructors. For each course participant (about 5,000),identified by a code, we want to store her social security number, surname, age, sex, place of birth, employer’s name, address and telephone number, previous employers (and periods employed), the courses attended (there are about 200 courses) and the final assessment for each course. We need also to represent the seminars that each participant is attending at present and, for each day, the places and times the classes are held. Each course has a code and a title and any course can be given any number of times. Each time a particular course is given, we will call it an ‘edition’ of the course. For each edition, we represent the start date, the end date, and the number of participants. If a trainee is self-employed, we need to know her area of expertise, and, if appropriate, her title. For somebody who works for a company, we store the level and position held. For each instructor (about 300), we will show the surname, age, place of birth, the edition of the course taught, those taught in the past and the courses that the tutor is qualified to teach. All the instructors’ telephone numbers are also stored. An instructor can be permanently employed by the training company or freelance.        

Note:It will be really helpful if you provide it on a paper by hand.

Answer 1

For the given scenario,

Entities are:

• Trainee
• Instructor
• Course
• Company

Key points:

• The participant can be an employee
• An Instructor can be a freelancer
• Courses that are offered can have editions

Relationships:

• The trainee is in relationship with Course and Company
• The instructor is in relationship with the Course
• The course is in relationship with Course and Instructor and Trainee
• Company is in relationship with Trainee

The result ER diagram is :