Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Usenet -> comp.databases.theory -> Re: Which normal form is this violating?

Re: Which normal form is this violating?

From: David Cressey <david_at_dcressey.com>
Date: Tue, 07 May 2002 03:54:12 GMT
Message-ID: <EdIB8.25$Bz4.5917@petpeeve.ziplink.net>


Joe,

Can you tell me when CREATE/ALTER/DROP DOMAIN were added to the SQL Standard?

Also, if I'm familiar with Oracle Rdb (formerly DEC Rdb) syntax for CREATE/ALTER/DROP DOMAIN is the SQL standard pretty much the same?

--
Regards,
    David Cressey
    www.dcressey.com
"--CELKO--" <71062.1056_at_compuserve.com> wrote in message
news:c0d87ec0.0205060840.435c6842_at_posting.google.com...

> >> People seem to leave more stuff out of their Usenet posts than
> their specs, so I figured it was at least equally reasonable to assume
> a FK existed. <<
>
> Probably is as reasonable; but I like making people think before they
> post. Spelling is another matter ...
>
> >> However, the PK-FK approach supports easier modification of the
> domain, via INSERT and DELETE statements. <<
>
> Hopefully, domains are not constantly changing.
>
> Right now the CREATE/DROP/ALTER DOMAIN statements in Standard SQL are
> basically in-line shorthands for column declarations. It is better
> than nothing, but not wht it could be. The SQL-99 User Defined Types
> are closer to a real domain concept.
>
> My rule of thumb is use CHECK() for small and/or constant domains
> (sex, state codes, etc.) and the PK-FK references for large and/or
> varying domains (stock market symbols).
Received on Mon May 06 2002 - 22:54:12 CDT

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US