Re: Composite attributes
Date: 19 Nov 2002 10:55:43 +0100
Message-ID: <3dda0a9f$1_at_news.uia.ac.be>
In article <6278687.0211181426.3480b5a4_at_posting.google.com>,
Juan Pardillos <sicotom_at_eresmas.com> wrote:
>Hi,
>
>I'd like to know if a composite attribute (e.g., a subject code like
>'CS2323', where 'CS' denotes the department and so on) can be in a
>relation or whether this is prohibited by the definition of relation.
>In other words, does the definition of relation prohibit composite
>attributes or only multivalued attributes?.
>
>I've got the same doubt regarding the first normal form. Depending on
>the text, I get a different opinion about the answer to this question.
The relevant question is if as far as the database is concerned it is treated as an atomic value. So you have to envision all the queries that are going to be asked and wonder if some of them will have to split 'CS2323' into 'CS' and '2323'. So as usual the answer is: it depends on what you want to do with the data.
- Jan Hidders