Multiple choice

Which of the following will not eliminates the ambiguities of a null value?

  1. Define the attribute as required

  2. Define subtypes

  3. Define each attribute as having an initial value that is recognized as blank

  4. Define supertypes

  5. None of these

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

Supertypes are more general entity types that contain subtypes. Defining supertypes doesn't address null value ambiguities - null ambiguities are typically resolved by defining attributes as required, setting default/initial values, or using subtypes to categorize data more precisely.