A key of a relation may have more than one attribute. True False
Question
A key of a relation may have more than one attribute. True False
Solution
True. A key of a relation in a database can indeed have more than one attribute. This is known as a composite key. A composite key is a combination of two or more columns in a table that can be used to uniquely identify each row in the table. Uniqueness is only guaranteed when the columns are combined; when taken individually the columns do not guarantee uniqueness.
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