• Courses
  • Tutorials
  • Jobs
  • Practice
  • Contests

GATE | GATE CS 2011 | Question 65

Consider a relational table with a single record for each registered student with the following attributes.
1. Registration_Num: Unique registration number
   of each registered student
2. UID: Unique identity number, unique at the 
   national level for each citizen
3. BankAccount_Num: Unique account number at
   the bank. A student can have multiple accounts
   or join accounts. This attribute stores the 
   primary account number.
4. Name: Name of the student
5. Hostel_Room: Room number of the hostel 
Which one of the following option is INCORRECT?

(A)

BankAccount_Num is candidate key

(B)

Registration_Num can be a primary key

(C)

UID is candidate key if all students are from the same country

(D)

If S is a superkey such that S∩UID is NULL then S∪UID is also a superkey

Answer

Please comment below if you find anything wrong in the above post
Feeling lost in the world of random DSA topics, wasting time without progress? It's time for a change! Join our DSA course, where we'll guide you on an exciting journey to master DSA efficiently and on schedule.
Ready to dive in? Explore our Free Demo Content and join our DSA course, trusted by over 100,000 geeks!

Last Updated :
Share your thoughts in the comments