Computer Science
Which of the following attributes cannot be considered as a choice for primary key ?
- Id
- License number
- Dept_id
- Street
Relational Database
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Answer
Street
Reason — Attributes "Id," "License number," and "Dept_id" are unique identifiers and can be suitable choices for a primary key. However, "Street" might not be unique for each tuple, as multiple tuples could have the same street value, making it unsuitable for a primary key.
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