Consider the following Data:
Student (sID, surName, firstName, campus, email)
Course (dept, cNum,
Offering (oID, dept, cNum, term, instructor)
Took (sID, oID, grade)
Offering [dept, cNum] ⊆ Course[dept, cNum]
Took [sID] ⊆ Student[sID]
Took [oID] ⊆ Offering[oID]
Based on the Data above answer the following query using relational algebra:(database)
- Give the Student number of all students who have taken the course number "343" by the department "CS".
- Find sID of all students who have earned some grade over 80 and some grade below 50.
- Find the Terms when the course number "369" by the department "CS" was not offered.
- Find the Department and course number of courses that have never been offered.