Re: Database design

x schrieb:
> You say a relation is flat because the attributes of a single tuple are all
> at the same "level" like (a1,a2,...,an) in R(A1,A2,A3,...,An) instead of
> something like (((a1,a2), (a3,a4)), a5, (a6,a7,a8),....) so the tuples are
> flat, not the relations.

Not precisely, but your interpretation is very close to what I tried to say and I think quite compatible (concerning tuples). But actually I do not insist on my interpretation of the term "flat". I simply describe what I find natural. The idea is very simple. If we have a set with elements then I tend to consider it flat because I do not see anything behind these elements and over this set. A single relation is precisely such a set without more specific and more general levels (if you consider only one relation - not many).

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