Re: Clean Object Class Design -- What is it?

Hi Akmal,

You should warn him that those products that equate object classes with relations make a fundamental error. A relation is a set of sets of object instances.

Regards,
Bob

akmal _at_ city wrote in message ...
>On 17 Jul 2001, Galen Boyer wrote:
>
>> On Mon, 16 Jul 2001, bbadour_at_golden.net wrote:
>>
>> >>Object databases take care of
>> >>inheritance hierarchies internally.
>> >
>> > As do relational databases.
>>
>> I don't understand how a relational database can represent
>> inheritance. Most of the time, I can take an object model and
>> logically map it to a relational model, because of, well, the
>> relationships, but how do you model inheritance in a DB?
>> --
>> Galen Boyer
>> It seems to me, I remember every single thing I know.
>>
>>
>
>Inheritance hierarchies have been the subject of some discussion within
>ANSI/ISO I believe. A number of Object-Relational products support it. You
>might wish to have a look at something like PostgreSQL:
>
>http://www.postgresql.com/
>http://www.postgresql.org/
>
>which is widely available.
>
>akmal
>
>--
>[ --- OOPSLA 2001 Workshop on "Objects, <XML> and Databases" --- ]
>[ http://www.soi.city.ac.uk/~akmal/oopsla01.dir/01-workshop.html ]
>
>
Received on Wed Jul 18 2001 - 06:37:36 CEST