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DC
Question Practice

When is a primary key allowed to have a NULL value?

Attempt the question, check the explanation, and continue with similar questions to build confidence before exams.

MCQ_SA
CBSE
Class 11
Informatics Practices
Informatics Practices
Database Concepts
Question Bank

When is a primary key allowed ...

Single Answer MCQ
Q-00066962

When is a primary key allowed to have a NULL value?

1

When it is a composite primary key

2

It should never have a NULL value

3

When it is used in a foreign key relationship

4

When there are multiple primary keys

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