You have answered the question correctly.6. Suppose we are to design a registrar's database to store information about students, courses, the courses students have taken, and the grades students have gotten in these courses. Courses have a number, a department, and a title, for example, "CS101: Introduction to computing" has department = CS, number = 101, and title = "Introduction to Computing." Numbers are assigned by departments, and different departments may use the same number. Students are represented by their (unique) student ID and their name. "Enrollments" each consist of a course, a student who took that course, and the grade the student got in the course. You should draw one or more E/R diagrams that represent this database structure correctly. Then, indicate which of the following might you find in a correct E/R diagram.a) Entity set Students with attribute ID underlined and name not underlined.b) Ternary relationship Enrollments connecting entity sets Courses, Students, and Grades, with an arrow to Courses.c) Entity set Students with attributes ID and name underlined.d) Entity set Courses with attribute department underlined and attributes number and title not underlined.
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- Fall '08
- Entity-relationship model, E/R Diagram