Difference between primary key a composite key

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Hi!!

Can you tell me the difference between a composite key and a primary key?
Sep 5, 2018 in Database by Sahiti
• 6,370 points
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2 answers to this question.

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Primary key is that column of the table whose every row data is uniquely identified. Every row in the table must have a primary key and no two rows can have the same primary key. Primary key value can never be null nor can be modified or updated.

Composite Key is a form of the candidate key where a set of columns will uniquely identify every row in the table.

answered Sep 6, 2018 by CodingByHeart77
• 3,740 points
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candidate  key: It is the collection of that coulmn or attributes in which values should not repeat within same column.
composite key:It is the collection of that columns or attribute in which values can repeat within same column.
answered Oct 14, 2020 by anonymous

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