Oracle FAQ | Your Portal to the Oracle Knowledge Grid |
Home -> Community -> Usenet -> c.d.o.server -> Re: design question
"Bruman" <uv_katastrophe_at_yahoo.com> wrote in message
news:1166042543.456028.182860_at_16g2000cwy.googlegroups.com...
>
> I recently played with the idea of creating a nested table. I do not
> know about the extra overhead on the DBMS but from a design standpoint
> can a table be normalized if it has them? According to my manual 1NF
> says that all column values must be atomic. It seems that this is
> moving away from that definition.
>
I don't think there is anything in Codd's original definition that precludes the use of table or array types as data types, provided you treat them as atomic types. In other words, you cannot 'peek inside' the structure of a value of a complex type to use the algebra on components of that type.
In other words you can only say things like:
where X = Y
if X and Y are values of the complex data type,
they may not be values of the sub-components of
the complex data type.
-- Regards Jonathan Lewis http://jonathanlewis.wordpress.com Author: Cost Based Oracle: Fundamentals http://www.jlcomp.demon.co.uk/cbo_book/ind_book.html The Co-operative Oracle Users' FAQ http://www.jlcomp.demon.co.uk/faq/ind_faq.htmlReceived on Wed Dec 13 2006 - 16:03:03 CST