Well personally I prefer single field primary keys because I find it eaiser to work with them....particularly when you need all those foreign keys in the other tables. But...if you're in a situation where you're either dealing with a lot of data or a lot of time to work on it, using the multipule fields is probably the "proper" way to do it.

>>Yes I agree that this is a much better solution.
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>Which of the proposed alternatives would you prefer, if you had to redesign a system?
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>Personally, I would prefer a single field (simpler relations and SELECTs). GUIDs would probably be easier to maintain, and many programmers seem to use them. But I would probably still prefer the second solution I proposed, since there is quite a difference in the space used.
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>But note that I never tried all this in actual practice - I have only thought about it (since I thought I would need it eventually).
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>Hilmar.