Which of the following constraints states that in a relation no primary key value can have a null value
Correct answer: B. Entity Integrity
- A. Referential Integrity
- B. Entity Integrity
- C. Data Integrity
- D. All of the above
Explanation
This constraint ensures that every row in a table can be uniquely identified by its primary key, and that the primary key cannot have a null value. This is because a null primary key would mean that there is no way to identify a specific row in the table
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