GUID vs INT IDENTITY

Question

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How do you like your primary keys?

I'm aware of the benefits of using a GUID, as well as the benefits of using and INT as a PK in a database. Considering that a GUID is in essence a 128 bit INT and a normal INT is 32 bit, the INT is a space saver (though this point is generally moot in most modern systems).

In the end, in what circumstances would you see yourself using an INT as a PK versus a GUID?

Answer 1

Kimberley Tripp (SQLSkills.com) has an article on using GUID's as primary keys. She advices against it because of the unnecessary overhead.