Re: APIs, messaging

[Uche Ogbuji <uche.ogbuji@fourthought.com>]

> A relational data model can be seen as objects without methods plus
> relational integrity rules.  You could argue that the rules are really there
> with objects, too, but they are usually added on later with procedural code
> (as business rules still have to be treated in relational models).

Worth noting that ODMG adds intrinsic binary relational integrity of
associations.  This is a nice step forward from "core" OO, but OODBMS
could take an even greater leap forward in expressivity with the addition
of N-ary relationships with integrity constraints.

Further note: I've pointed out before, ODMG's ability to have collections
as the end-points of binary relationships are not really the equivalent
of N-ary relationships.

Of course, with XLink, XML has its N-ary relationships.  Bravissimo.


-- 
Uche Ogbuji                               Principal Consultant
uche.ogbuji@fourthought.com               +1 303 583 9900 x 101
Fourthought, Inc.                         http://Fourthought.com
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