DATABASE FUNDAMENTALS
WHAT IS DATABASE MANAGEMENT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Primary Key
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Foreign key
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Super key
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Candidate key
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Detailed explanation-1: -31. Set of one or more attributes taken collectively to uniquely identify a record is called? Explanation: Super Key is a set of one or more attributes taken collectively to uniquely identify a record.
Detailed explanation-2: -A relation can have one or more attributes that takes distinct values. Any of these attributes can be used to uniquely identify the tuples in the relation. Such attributes are called candidate keys as each of them are candidates for the primary key.
Detailed explanation-3: -A superkey is a set of one or more attributes that, taken collectively, allow us to identify uniquely an entity in the entity set.
Detailed explanation-4: -Super key is a single key or a group of multiple keys that can uniquely identify tuples in a table. Super Key can contain multiple attributes that might not be able to identify tuples in a table independently, but when grouped with certain keys, they can identify tuples uniquely.
Detailed explanation-5: -A key is an attribute or set of attributes which helps us in uniquely identifying the rows of a table.