An instance of relational schema R (A, B, C) has distinct values of A including NULL values. Which one of the following is true?
| A. | A is a candidate key |
| B. | A is not a candidate key |
| C. | A is a primary Key |
| D. | Both (A) and (C) |
Answer : B Explanation : |
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Option: A Explanation : Explanation will come here. Explanation will come here. Explanation will come here. Explanation will come here. Explanation will come here. |
