In a Students table with columns StudentID, FirstName, LastName, and Email, which combination of columns can be considered a super key?Group of answer choicesEmailAll of the aboveStudentID, FirstNameStudentID
Question
In a Students table with columns StudentID, FirstName, LastName, and Email, which combination of columns can be considered a super key?Group of answer choicesEmailAll of the aboveStudentID, FirstNameStudentID
Solution
A super key in a database is a group of single or multiple keys which identifies rows in a table. It's a set of attributes, one or more, that can uniquely identify a record in a table.
Looking at the options provided:
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Email: This could be a super key if every student has a unique email.
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All of the above: This could be a super key as it includes all columns and certainly would be unique for each student.
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StudentID, FirstName: This could be a super key if the combination of StudentID and FirstName is unique for every student.
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StudentID: This could be a super key if the StudentID is unique for every student.
So, the answer is "All of the above" if each of those combinations uniquely identifies a record in the table.
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