Multiple choice

In SQL, a relation can contain null values, and comparisons with null values are treated as unknown. If all the comparisons with null values are treated as false, which of the following pairs is equivalent?

  1. x = 10 not (not x = 10)

  2. x = 10, x > 9 and x < 11, where x is an integer

  3. x $\ne$ 10 not (x = 10)
  4. Both (1) and (2)

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

null