Semester Examination SystemDBMS Lab Assignment Group - III Srimanta Singh (004) Samik Saha (015) Prasenjit Gayen (016) 3rd yr. 1st sem., Department of Computer Sc. & Engg. Jadavpur University Exam can be of two types –regular and supplementary.. Same subject (name) in two courses or department is separately identified by the corresponding subject_id. WE have assumed that a teacher can take classes in different department but he will belong to a particular department. Subject_id for a course of a department is unique. A student must register to appear in the exam. A registered student is considered as exam candidate. A particular department may offer few courses. .The university has many departments which are identified basically by the department_id. In case of supplementary a candidate may not have to appear in all the subjects assigned to a particular semester. He also has to make question paper and evaluate the answer script. Each teacher is assigned to teach a particular subject.ASSUMPTIONS Data requirements: The major characteristics of the semester examination system are……. One or more subjects may be same for different courses as well as departments. Each department has teachers. The exam controller section is the administrator of this whole examination system. Also the departments have a particular location (campus). Subject_id . and each student also has a registration number. ENTITY SETS 1.Teacher 4. Grade. Contact No Department_id.Subject 5. Exam_id. Department: University has so many departments. name.. 6. Contact No. Reg. Location Teacher_id. Sub_id 7. each student has a roll no by which they are identified uniquely.ENTITY SETS USED IN E-R DIAGRAM For constructing a conceptual schema of this data base.Exam ASSOCIATED ATTRIBUTES Name. Sub_id. the entity sets and the associated attributes are given below (as our specification of the E-R diagram)…………………………. .Routine Roll no. Roll No. Name.Department 3. Sub_id. Date_of_publish Date. Exam_id. Status Name. Room No. The departments have their respective location and contact number. Exam_id Student: Student enrolls in a course in a particular department. Each student has to enroll to appear in the examination as a candidate.Student 2. Year.Result 8. No. Roll No. Each department has a unique department_id. Exam roll no.Course. A student also have also have contact number and address. Dept Exam_id. Time.Exam Candidate Semester. Name. Exam Candidate : Each student has to register his name for the examination. semester and year in which the exam is taken. Each teacher is uniquely identified by the attribute teacher_id. A candidate is uniquely identified by his exam roll no. name and status. All attributes are atomic. and exam_id. sub_id and exam_id. subject_id. time. . subject_id. Exam_id is the primary key of this entity. roll no. exam_id. Result : Each exam must have their corresponding results. Result is also associated with the students. Exam : The whole semester examination system is organized in few exams. . Same subject can be taught in several departments but in that case the subject_id will be different. Thus the result of a student of a particular semester is identified using roll no. The subjects are uniquely identified by their corresponding subject_id. of the teachers may have multiple values.. Each teacher has their corresponding teacher_id. room no. contact no. Contact no. Subject: Each department offers many courses and each course consists of subjects. Exam may be of two types – regular and supplementary. These exams are identified by the exam_id. Here each subject have subject name. Teacher Each department has many teachers. It contains candidate name. It also contains grade and date of publication of the result as attributes Routine : Each exam has a corresponding routine which consists of date. After registration for the exam he achieves the candidature for that particular exam. Teaches This is the many-to-many binary relationship sets between teacher and subjects. Holds This is a many-to-many binary relationship set between the department and the examination. . Because. and year.for a particular department there are many teacher but for a teacher only 1 department is fixed. We also have a one-to-one binary has relationship between the exam and the exam results. And the participation of the weak entity set. Sits for This is a many-to-many binary relationship sets between the Exam Candidate and the Examination. Enrolls This is the one-to-one binary relationship sets between Student and Exam Candidate. Component attributes are: date. month. Belongs to This is the 1-to-many binary relation ship set between DEPARTMENT and TEACHER sets. Scheduled This is the relationship that holds between the examination and the exam routine.RELATIONSHIP SETS FOR DATA BASE In our E-R diagram specified relationship sets and mapping cardinalities are described below: Has This is the 1-to-many binary relationship set between department and student entity sets. And the participation of the teacher entity sets in this relation ship sets is partial. ISA This is a relationship set that holds between the exam and the two category of exam-regular and supplementary. . Of This relation holds between the exam and subjects as well as the subject and results. Gets This is the relationship sets between Exam Candidate and the Results. (fk) assigne d to teaches sem year exam-id exam sub-id (fk) ISA of subject name enrolls scheduled routine time room no date exam-id (fk) Sub-id regular sits for supplementary of has exam-id (fk) enrolled gets sub-id sub-id grade roll no. no. no. (fk) exam-id (fk) roll no. teacher teacher-id has of sub-id name roll no. name belongs to department contact no. contact no. student regd. no. results Date published . dept.name dept.