gadfly RDBMS ???

[Marc POINOT]

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. ]