Do I have to declare a foreign key as identity

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I have one table that's primary key is an identity. I am adding this PK as a foreign key in a different table but wandered if i still had to set this foreign key column to identity?

What I have tried:

I have looked to see if this was necessary in other forums but cannot find an answer.

Posted 11-Apr-18 0:45am

Member 13771716

Updated 13-Apr-18 6:15am

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Solution 2

Agree with Balboos. Your foreign key column must have the same value as the primary key column it's referencing in the other table. If your foreign key column were an IDENTITY column then it would be creating new values for every record. Those values would not necessarily match the values in the primary key column you're referencing. That would contradict the purpose of creating the foreign key.

Posted 13-Apr-18 6:16am

David C. Williams

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W∴ Balboos, *GHB* · Accepted Answer · 2018-04-11T00:50:00

Absolutely NOT !

1 - The foreign key is used for a one-to-many relationship. It ties together a parent record with any amount of child records.
2 - The foreign key is declared to prevent any records from being in the child table that have no reference (primary key) in the parent table. This helps insure referential integrity.

If you need to force only a single child record for each parent record but still maintain the foreign key constraint the add a UNIQUE constraint to the column, as well.