DBMS · Question 28 · Hard
Relation R(A, B, C, D, E) has exactly two candidate keys, A and B. How many superkeys does R have?
- 16
- 32
- 31
- 24
Answer and explanation
Answer: D. 24
Explanation: Superkeys containing A: 2^4 = 16. Superkeys containing B: 16. Those containing both A and B (2^3 = 8) are counted twice, so the total is 16 + 16 - 8 = 24.
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