This document provides the required data and entity relationship (ER) diagram for a student marks database for a university. It includes student information, courses, exams, and marks. Tables are created from the ER diagram for students, exams, course offerings, and course marks. The course marks table is normalized to first, second, and third normal forms by removing non-key dependencies to improve data integrity.

1. Database System
Assignment
On
Submitted To :
Sir MD. Shohel Mojumder
Lecturer, Bangladesh University
Department of CSE
Submitted By :
MD. SADIQUR RAHMAN
ID : 201531043092
Batch No : 43
Department of CSE
BANGLADESH UNIVERSITY
15/1, Iqbal Road, Mohammadpur, Dhaka-1207

2. 1
Required Data
Required data for creating a student marks database
of a university:
1. For student information each student has a unique ID.
2. Each student has a name.
3. Each student takes a Program.
4. Versity offers courses for students.
5. Offering course have Course time limit, Section number
& Room number.
6. Each Course should have a unique ID.
7. Offering Course have Semester & Year.
8. Versity takes Exam & Every exam have a specific Exam
ID.
9. Each exam has subject, exam place & exam time.
10. Finally have marks of each student for each course.

3. 2
ER Diagram

4. 3
Snapshot :
Student (Sid, Sname, Program, Sec_no)
Course_offreing (Sec_no, Time, Room, Course_no, Semester, Year)
Exam (Eid, Ename, Eplace, Etime)
Takes (Sid, Eid, makes, Sec_no)
Student
Sid Sname Program Sec_no
Course Offering
Sec_no Time Room Course_no Semester Year
Exam
Eid Ename Eplace Etime
Takes
Sid Eid Sec_no Marks

5. 4
Tables
Table made from ER diagram.
Students
Student ID. Name Program
10131 Akash CSE
10132 Karim BBA
10133 Jamail LAW
10134 Habib EEE
Exam
Exam ID. Name Place Time
43138 DBMS Mirpur 10.00 am
43139 Accounting Bobani 2.00 pm
43140 English Gulshan 12.00 pm
43141 DLD Mohakhali 10.00 am

6. 5
Course Offerings
Time Section No Room Course No Semester Year
4 months 3A 001 CSE-312 Fall 2017
4 months 3E 122 BUS-315 Fall 2016
4 months 4C 243 ENG-112 Spring 2015
4 months 5A 359 EEE-111 Summer 2016
Course taken by Students and their marks in
exams:
Student ID Course No Exam ID Marks
10131 CSE-312 43138 81
10132 BUS-315 43139 68
10133 ENG-112 43140 85
10134 EEE-111 43141 81
10134 CSE-312 43138 75
10131 BUS-315 43138 68
10132 ENG-112 43140 75

7. 6
Normalization
We will use three types of normalization:
1. First normal form(1NF)
2. Second normal form(2NF)
3. Third normal form(3NF)
Let’s begin. We can normalize the marks in exams table as it’s already in
first normal form.
Student ID Course No Exam ID Marks
10131 CSE-312 43138 81
10132 BUS-315 43139 68
10133 ENG-112 43140 85
10134 EEE-111 43141 81
10134 CSE-312 43138 75
10131 BUS-315 43138 68
10132 ENG-112 43140 75
Now it’s time for second normal form. The roles for second
normal form is:
 Table is in 1NF (First normal form)
 No non-prime attribute is dependent on the proper subset
of any candidate key of table.

8. 7
As we can see there are two candidate keys: (Students ID, Course
NO).
And a non-prime attribute: (Marks).
Because to find out a student exam mark in a specific subject we
need that subject’s course ID/ course no. So marks a non-primitive
attribute is functionally dependent on students ID and course no.
both.
We have to remove this dependency.
We will create a table with students ID and Course No.
Student ID Course No
10131 CSE-312
10132 BUS-315
10133 ENG-112
10134 EEE-111
10134 CSE-312
10131 BUS-315
10132 ENG-112

9. 8
And a table with Course No, Exam ID, Marks.
Course No Exam ID Marks
CSE-312 43138 81
BUS-315 43139 68
ENG-112 43140 85
EEE-111 43141 81
CSE-312 43138 75
BUS-315 43138 68
ENG-112 43140 75
THE END