Anonymous
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Cars &Transportation
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2 weeks ago
Do you need a primary key if you have a foreign key?
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Does a foreign key need a primary key?
Yes, foreign key has to be primary key of parent table. Yes, it may not be unique and may have duplicate entries in child table, but it must be unique and does not have any duplicate entries at the parent table (as it is a primary key).
Can a table have a foreign key without a primary key?
From Books Online: A FOREIGN KEY constraint does not have to be linked only to a PRIMARY KEY constraint in another table; it can also be defined to reference the columns of a UNIQUE constraint in another table. So in your case if you make AnotherID unique, it will be allowed.
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