Question-8

Given an instance of the STUDENTS relation as shown below:

Student ID	Student Name	Student Email	Student Age	CPI
2345	Shankar	shankar@math	X	9.4
1287	Swati	swati@ee	19	9.5
7853	Shankar	shankar@cse	19	9.4
9876	Swati	swati@mech	18	9.3
8765	Ganesh	ganesh@civil	19	8.7

For \((\text{Student Name}, \text{Student Age})\) to be a key for this instance, the value \(X\) should NOT be equal to \(\_\_\_\_\).

Answer

\(19\)

Solution

In order for \((\text{Student Name}, \text{Student Age})\) to serve as a key, it must uniquely identify each tuple in the relation. In this instance, we observe that both “Shankar” and “Swati” have the same age of \(19\). To maintain uniqueness, the value of \(X\) cannot be \(19\), ensuring that each combination of \((\text{Student Name}, \text{Student Age})\) remains distinct. Hence, \(X \neq 19\) satisfies the criteria for \((\text{Student Name}, \text{Student Age})\) to be a key.