GATE CSE 2000 | Question: 2.24

Question

Given the following relation instance.

$$\begin{array}{|l|l|}\hline \text{X} & \text{Y} & \text{Z} \\\hline   \text{1} & \text{4} & \text{2} \\   \text{1} & \text{5} & \text{3} \\  \text{1} & \text{6} & \text{3} \\ \text{3} & \text{2} & \text{2} \\\hline \end{array}$$

Which of the following functional dependencies are satisfied by the instance?

• A. $XY \rightarrow Z$ and $Z \rightarrow Y$
• B. $YZ \rightarrow X$ and $Y \rightarrow Z$
• C. $YZ \rightarrow X$ and $X \rightarrow Z$
• D. $XZ \rightarrow Y$ and $Y \rightarrow X$

Answer 1

Ans: B YZ → X and Y → Z