Re: Artificial Primary keys

--CELKO-- wrote:

> >> Or could you give an example - that is: of a natural key that holds
> information, but is immutable? <<

> DNA.
With organ transplants and the like, I wonder what potential there is for mutability here.

A sample of a person's DNA taken from (what you think is) their liver might not be the same as the DNA taken from their blood 6 years earlier, if the liver has been changed for a new one.

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Ben Clifford  
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