Multiple choice

From the following instance of relation schema R(A,B,C), we can conclude that

A B C 1 1 1 1 1 0 2 3 2 2 3 2

  1. A functionally determines B and B functionally determines C

  2. A functionally determines B and B does not functionally determine C

  3. B does not functionally determine C

  4. A does not functionally determine B and B does not functionally determine C
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A is said to be functionally determined by B. A has the same values as that of B for every corresponding tuple in given the database,

A B 1 1 1 1 2 3 2 3

Here if A is 1, then B is necessarily 1 and if A is 2, then B is 3. So, B is functionally determined by A. But this relationship is not true for any other pair.

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