Re: Define "flatten database" ?

From: Mark Johnson <>
Date: Fri, 24 Feb 2006 21:43:30 -0800
Message-ID: <>

Jan Hidders <> wrote:

>1NF: in some cases they tell you to immedeately split off the nested
>columns into separate relations (thus avoiding redundancy) and in others
>the relation is merely flattened and the splitting off is postponed to
>the later normalization steps. So the question is this. Can we always
>use both approaches and if we can does it matter for the end result
>which one we take?

Which some, here, find quite objectional is that reference to a table/relation as being in any way, 'flat'.

As for the question, I suspect you had an answer in mind. I don't see that it would matter as the 'splitting' is to be done on the same columns on the same table, at whatever point one decides to do so.

Perhaps I might ask a related question. Do you believe that a table corresponds, but perhaps only weakly, or even inconsistently, to a "relation" as understood in the set theory of the RM, or do you believe it is fair to call the database table a "relation", without much qualification? Received on Sat Feb 25 2006 - 06:43:30 CET

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