In SQL, relations can contain null values, and comparisons with a null values are treated as unknown. Suppose all comparisons with a null value are treated as false. Which of the following pairs is not equivalent?

x = 5 x > 4 and x < 6, where x is an integer

In SQL, relations can contain null values, and comparisons with a null

1.	In SQL, relations can contain null values, and comparisons with a null values are treated as unknown. Suppose all comparisons with a null value are treated as false. Which of the following pairs is not equivalent?
A.	x = 5 not (not (x = 5)
B.	x = 5 x > 4 and x < 6, where x is an integer
C.	x 5 not (x = 5)
D.	None of the above
Answer» D. None of the above

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In SQL, relations can contain null values, and comparisons with a null values are treated as unknown. Suppose all comparisons with a null value are treated as false. Which of the following pairs is not equivalent?

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