From time to time I see articles in defense of natural primary
keys against surrogate keys.I don't take an immovable stand on
either side, as I have seen good cases for both. In general, I
like the idea of a natural primary key, when I see one that it is
really natural. Quite often, though, a natural primary key has
proved itself faulty. And most of the times, when such faults
happened, it was because of limited understanding of the data. I
like to describe this kind of misinformation as data analysis
culture clash.When choosing a natural primary key, one should
consider which element, or group of elements, are unique in a
given set. Not only that, they must be immutable, at least within
that set.For example, in a group of people, we may assume that a
combination of name, surname, date and place of birth is a good
natural primary key. Well, no. It isn't, for several reasons.
Read on for a few real cases.If we rule out the above
combination, …
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