Re: does a table always need a PK?

Lee,

"Lee Fesperman" <firstsql_at_ix.netcom.com> kirjoitti viestissä news:3F4C6EC1.5FEA_at_ix.netcom.com...
> Heikki Tuuri wrote:
...
> > Lee, of course, has a commercial interest in claiming that 'a/the
relational
> > model' is crystal clear. He tries to market FirstSQL on that basis.
> >
> > "* FirstSQL/J Object/Relational DBMS "
> >
> > By the way, FirstSQL probably is not Codd-12-relational? Why do you
claim it
> > to be an 'object/relational' database then? Is it 'Lee
> > Fesperman -relational'?
>
> FirstSQL/J is not yet compliant with all of Codd's 12 Rules. However, we
are improving
> in that area and are the only DBMS vendor dedicated to relational
fidelity. It's on our
> to-do list!

I thought that also Dataphor is dedicated to some version of 'relational fidelity'. Do you dispute that?

Could we say that your database is an 'object/TODO-Codd-12-relational' database?

> Codd's 12 Rules do not define the relational model; they are guidelines
for users to
> evaluate the relational compliance of their DBMSs. For more definitive
information, see
> Codd's papers beginning with the 1970 article through his 1979 "Extending
the Database
> Relational Model to Capture More Meaning".

Good. Please show us where the following are formally defined by Codd?

http://www.cis.ohio-state.edu/~sgomori/570/coddsrules.html:

"
9. Logical Data Independence
Application programs and terminal activities remain logically unimpaired when information preserving changes of any kind that theoretically permit unimpairment are made to the base tables. "

Or:

"
6. View Updating Rule
All views that are theoretically updateable are also updateable by the system.
"
?

...
> --
> Lee Fesperman, FirstSQL, Inc. (http://www.firstsql.com)
> ==============================================================
> * The Ultimate DBMS is here!
> * FirstSQL/J Object/Relational DBMS (http://www.firstsql.com)

Best regards,

Heikki Tuuri
Innobase Oy
http://www.innodb.com
Foreign keys, transactions, and row level locking for MySQL InnoDB Hot Backup - a hot backup tool for MySQL Received on Wed Aug 27 2003 - 14:04:09 CEST