A school wants to store details of students and their marks in two related tables, Student and Marks. Suggest suitable Primary Key and Foreign Key for these tables and explain why they are needed.

Question

Accepted Answer

In the Student table, StudentID can be the Primary Key since it uniquely identifies each student. In the Marks table, Student ID can be a Foreign Key referring to the Student table's StudentID, so that each mark record is linked to a valid, existing student. These keys are needed to avoid duplicate student records and to ensure that marks are only recorded for students who actually exist in the Student table.