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Re: Normalization by Composing, not just Decomposing

From: Dawn M. Wolthuis <dwolt_at_tincat-group.com>
Date: Mon, 12 Apr 2004 10:24:09 -0500
Message-ID: <c5ecb7$e2f$1@news.netins.net>


"Alan" <alan_at_erols.com> wrote in message news:c5e6m0$lo87$1_at_ID-114862.news.uni-berlin.de...
> Realtional theory as a data theory is analagous to democracy as a form of
> government- it may not be perfect, but so far, there's nothing better in
> most cases.

Have you concluded this by reviewing some emperical data that has been collected or because you adhere to some philosophy or what? Could I state something contradictory with as much logical backing?

> Denormalization in itself has nothing directly to do with OLAP, except
that
> one may denormalize more for an OLAP application than an OLTP application.
> However, in OLAP, you are not necessarily denormalizing so much as
> "re-normalizing", in that you are really developing a diiferent
distribution
> among entities for the same data, such as in a star schema. It's not
> normalized, but it's not denormalized either. It's just different. I
suppose
> an argument could be made that (in the case of a star schema), you start
> with a normalized schema, and then apply transformation rules (no, don't
ask
> me what they are- there are books on the topic) to transform it into a
star
> schema. Think about it- a basic star schema is essentially a giant
> many-to-many linking table (the fact table) with a bunch of descriptive
data
> tables (dimensions).

Are you adhering to relational theory when deploying an OLAP database where the data is in fact & dimension tables? I have not seen a star schema for the purposes of OLAP without some rules broken such as duplication of data. But I'm fine with it either way -- just curious whether most relational theorists would view data modeled as OLAP cubes as following "the ules". --dawn
<snip> Received on Mon Apr 12 2004 - 10:24:09 CDT

Original text of this message

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