Re: Object-relational impedence

On 2008-03-04, Dmitry A. Kazakov <mailbox_at_dmitry-kazakov.de> wrote:
> On Tue, 4 Mar 2008 15:41:40 +0000, Eric wrote:
>
>> On 2008-03-04, Dmitry A. Kazakov <mailbox_at_dmitry-kazakov.de> wrote:
>>> On Mon, 3 Mar 2008 23:03:41 +0000, Eric wrote:
>>>
>>>> No, RDBs partition data so that it is sensibly and easily available to
>>>> any possible application. So if you use OO you are saying "there will
>>>> never be any other application that will need my data".
>>>
>>> No, it is engineering which says so. It translates as "put the requirements
>>> first," or simpler "pigs do not fly."
>>
>> So no-one ever says "we should be able to get that stuff out of the xyz
>> application and combine it with our data so that we can..."!
>
> You should plan this use case in advance. That would be a requirement. A
> system can only do things it was designed for. (This applies to RDBMS as
> well). For each application exist things it cannot do. That implies: either
> A) there will never be any other application that will ask to do these, or
> B) the application is incorrect (= does not fulfill the requirements).
>

So you will always know, in advance, what all the possible future applications will want! I hope you are not crazy enough to believe that. So you are left with minimising "things it cannot do". I guess that means you should have something which can make the data available to any application that asks, according to any logically possible criterion. Did you know that this is what an RDBMS does?

Perhaps not, since you have also said that "data are irrelevant".

E Received on Tue Mar 04 2008 - 18:58:02 CET