COMPUTER SCIENCE AND ENGINEERING
SQL
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Which of the following attributes can be considered as a choice for a primary key?
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Name
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Street
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RollNo
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Subject
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Explanation:
Detailed explanation-1: -Which one of the following attribute can be taken as a primary key? Explanation: The attributes name, street and department can repeat for some tuples. But the id attribute has to be unique. So it forms a primary key.
Detailed explanation-2: -A primary key is either an existing table column or a column that is specifically generated by the database according to a defined sequence.
Detailed explanation-3: -Integer (number) data types are the best choice for primary key, followed by fixed-length character data types.
There is 1 question to complete.