We wish to create a database for a company that runs training
courses. For this, we must store data about trainees and
instructors. For each course participant (about 5,000 in all),
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.