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gadfly RDBMS ???

Darko Cvagic darko.cvagic at arcus.tel.hr
Wed Jul 21 11:42:55 EDT 1999 
Marc POINOT wrote:
> 
> Oleg Broytmann wrote:
> 
> > On Wed, 21 Jul 1999, Darko Cvagic wrote:
> > > What does it means that GADFLY is Relational ?
> >
> >    Because Gadfly is almost Yet Another SQL Engine (not that I am against
> > Gadfly or SQL).
> >
> > > How can I make relations between tables in database?
> >
> > SELECT t1.bor, t1.belt, t2.der
> >    FROM table1 t1, table2 t2
> > WHERE t1.plux = t2.flax
> >
> 
> SQL is a query langage, OSQL is an extension to OODBMS (Object oriented).
> 
> The "relationnal" model is an old model of data [1] but it as a theorical
> background
> with set theory, and it is widely spread in the industry.
> Say you have a set of tables, each table can be viewed as
> the subset of the cartesian product of to sets.
> 
> For more info, I think you can read some good books about
> DBMS history, such as [2].
> 
> [1] The Entity-Relationship model - toward a unified view of data
> P.P.-S. Chen, MIT, Readings in Database systems, M.Stonebraker,
> Morgan Kaufmann, 1988
> [note: paper is from ACM 1976]
> 
> [2] Principle of database systems - J. D. Ullman, Computer
> science press1982
> 
> Marcvs [alias Hum, I'm quite pleased about this pedantic and obscure answer. ]

Thanks, I think that I'm exchange terms like RELATION and LINK
So, Gadfly IS RELATIONAL, but I can't make something like:
	CREATE LINK order_customer
	FOREIGN KEY order(cno)
	REFERENCES customer
	ON DELETE RESTRICT

I can't do it in gadfly, am I wright?  
What is name for construction like this? 
I was thought that it is RELATIONAL , I was wrong!
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