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Question
______ is a non-key attribute, whose values are derived from the primary key of some other table.
Options
Primary Key
Foreign Key
Candidate Key
Alternate Key
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Solution
Foreign Key is a non-key attribute, whose values are derived from the primary key of some other table.
Explanation:
- Primary Key - It is used to uniquely identify the tuples in a relation.
- Foreign Key - It is used to represent the relationship between two tables/relations and its value is derived from the primary key of some other table.
- Candidate Key - refers to the set of all attributes which can uniquely identify records in a relation.
- Alternate Key - It is a candidate key that has not been selected to be the primary key.
So, the correct answer is Foreign Key.
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