Now draw the following problems: 1) A firm wants to make a database of movies in the following way: Movies are directed by directors and acted by actors and actresses. And users will give review or rating to specific movie, actor, actress and director on review section. A movie has a specific image, movie ID, story line, title, year, genre and amount of profit. Actors, actresses and directors have full names, IDs, birthdays, ages, images, biographies, home countries. And every user has unique username, first name, last name, password, email. And review will contain review id, category, comment and rating. Now use entity-relationship diagram (ERD) to design the concept of this situation. 2) In a school, there are teachers and students. Teachers take subjects, take exams and give marks to the students. Identify some attributes of teachers, exams, marks and students and then use entity-relationship diagram (ERD) to design the concept of this situation. 3) In a bookstore, we have to consider authors, books, criticisms. Authors will write books and criticism will criticize the works. An author has author ID, full name, date of birth, date of death, region, era and description. A work has ID, title, year and pages. A criticism has, URL, title, summary and publication. Now use entity-relationship diagram (ERD) to design the concept of this situation. 4) Clients will buy cars with the help of salesmen in a car storehouse. A car has license number, model, manufacturer and year. A client has ID, full name, address, phone number and date of purchase. A salesman has ID, first name, last name, address, date of joining and phone. Now use entity-relationship diagram (ERD) to design the concept of this situation. 5) Workers work in projects and each worker belongs to one specific department. Workers also give orders which contain order date, orderID, delivery date, amount and supplier. Each worker has WorkID, name, address, date of birth, date of joining and age. Each project has project id, project name, cost and time. Each department has dept_ID, name and specific address. Now use entity-relationship diagram (ERD) to design the concept of this situation. 6) Employees work for departments which control projects. Employee works on projects and each employee has dependent(s). Each employee has name, address, DOB and Salary. Each department has number, location and name. A project has ID, name and location. A dependent has name, relationship, date of birth and age. Now use entity-relationship diagram (ERD) to design the concept of this situation. 7) Customers purchase mobile phones. Mobiles maintain logins; customers pay bills and maintain logins. Identify some attributes of customers, mobiles, logins and bills and then use entity-relationship diagram (ERD) to design the concept of this situation
