Here i am sharing the solution of Assignment No.02 CS 101 for the Semester Fall 2022.You have to just take idea from this post, plz do not copy paste other wise you will be marked as Zero.
CS101 Assignment 2 Solution 2023/ CS101 Assignment 2 Solution semester fall 2022
A software developer has built a relational database model for the Learning Management System of an online learning website. Various relations (tables) are defined to store data records related to each entity in a separate relation. Three of the Relations (STUDENT, COURSE, and ENROLLMENT) defined in that database model along with their attributes are given below:
STUDENT
StudentID | StudentName | DegreeProgram | ResidentCity |
… | … | … | … |
… | … | … | … |
… | … | … | … |
COURSE
CourseCode | CourseTitle | TeacherID | DegreeProgram | CreditHours |
… | … | … | … | … |
… | … | … | … | … |
… | … | … | … | … |
ENROLLMENT
StudentID | CourseID | Semester |
… | … | … |
… | … | … |
… | … | … |
The developer needs to extract the following information given in Table-1 from his defined database model using the relational database queries that consist of SELECT, PROJECT and JOIN operators.
Table-1: Required Information
Sr. No. | Information required to be Extracted |
1 | Extract all the students from the STUDENT table belonging to a specific city. |
2 | Extract all the students from the STUDENT table who are enrolled in “BSCS” degree program. |
3 | Extract all the records in the columns “Student Name” and “Degree Program” of the STUDENT table. |
4 | Extract all the records in the columns “Course Code”, “Course Title” and “Degree Program” of the COURSE table. |
5 | Extract all the courses from the COURSE table having three or more credit hours. |
6 | Join STUDENT and COURSE tables using the Degree Program attribute. |
Now, in the below given table (Table-2), some relational database operations (Queries) related to the above database model are defined along with the name of resulting new relation. The name of the resulting new relation is also used as reference to identify that query (i.e. each query is referenced as A, B, C, D, E, F, G, H, I, J, K, and L).
Table-2: Relational Queries
Relational Query (Operation) | Name of the Resulting Relation (also a Reference Label) |
A <- SELECT from STUDENT where ResidentCity=’Lahore’ | A |
B <- PROJECT from STUDENT where City=’Lahore’ | B |
C <- PROJECT [CreditHourse>=3] from COURSE | C |
D <- JOIN STUDENT and COURSE where STUDENT. DegreeProgram=COURSE.DegreeProgram | D |
E <- PROJECT CourseCode, CourseTitle, DegreeProgram from COURSE | E |
F <- SELECT from STUDENT where DegreeProgram = ‘BSCS’ | F |
G <- JOIN COURSE and STUDENT on Column.DegreeProgram | G |
H <- PROJECT from COURSE Columns[CourseCode, CourseTitle, CreditHours] | H |
I <- PROJECT StudentName, DegreeProgram from STUDENT | I |
J <- SELECT Columns[StudentName, DegreeProgram] from STUDENT | J |
K <- SELECT [DegreeProgram = ‘BSCS’] from STUDENT | K |
L <- SELECT from COURSE where CreditHours >=3 | L |
This table (Table-2) contains both syntactically correct and incorrect relational database queries (referenced as A to N). Out of these twelve (12) queries, six (6) syntactically correct queries can be used to extract the information required in the table-1.
You are required to identify the correct relational database query from Table-2: Relational Queries for each of the “Required Information” entry in Table-1 and mention its reference label in the 2nd column of the below given table against the Sr. no. of Required Information. For example, the answer to “Sr. no. 1” entry of “Required Information” column is query “A” which is solved in the below given table.
Now, you need to fill the remaining five (5) entries in the below given table with the Reference label of correct relational database against each Sr. No. of the required information table.
Answer
Sr. No. of Required Information given in Table-1 | Reference label of the Correct Relational Query {Out of A, B, C, D, E, F, G, H, I, J, K, L} from Table-2 |
1 | A |
2 | K |
3 | I |
4 | E |
5 | L |
6 | G |