Re: In an RDBMS, what does "Data" mean?
Date: Mon, 14 Jun 2004 16:07:57 -0500
"Tony" <andrewst_at_onetel.net.uk> wrote in message
> "Dawn M. Wolthuis" <dwolt_at_tincat-group.com> wrote in message
> > Combination of metadata and data that is designed out of the relational
> > model, such as orderings, and attributes with cardinality > 1 that are
> > trimmed back to 1 for the relational model.
> > Did that help or am I digging a deeper hole? --dawn
> Yes, you are. Well, at least you are wrong. The relational model
> doesn't force you to "design out" anything.
No, it rather encourages it, however.
> If an ordering is
> required, then the relational model requires that you state it
> explicitly via an additional attribute, that is all. Attributes with
> cardinality > 1 are moved to a separate table by the normalisation
> process - again without loss of any information (not even
Ye-es, but, have you seen corporate implementations of the relational model(ish)? I'm particularly fond of those implementations where a single value is turned into a multivalue with the application developer coming up with a proprietary delimiter for a specific field so they can parse it. There are more instances when work is done to try to come up with single scalar values when multiples would make more sense.
cheers! --dawn Received on Mon Jun 14 2004 - 23:07:57 CEST