Re: Unknown SQL
Date: Wed, 30 May 2001 19:50:37 +0100
Message-ID: <a7gahtcn2ndc19o6r7l0i0r46c8g206rit_at_4ax.com>
>this is a very simple and good example where a flat, textual representation
>of data seems to beat objects. I wonder why none of the other gurus here has
>come up with the question yet.
It is worth mentioning that the relational model does not facilitate for functions of aggregates (as Mikito hinted). The addition of the GROUP BY / HAVING clause to SQL caused a large amount of hastle with getting the specification right, and made the spec considerably more messy, since it is not natural to the relation model (according to my lecturer, Ken Moody, Univ of Cambridge UK).
Thus if aggregation is difficult in an object-oriented context this is not necessarily a disadvantage compared with the relational model.
The ODMG Object Model (OQL) and SQL3 support SQL2-style aggregation, although both are quite hybrid. Received on Wed May 30 2001 - 20:50:37 CEST