Re: The wisdom of the object mentors (Was: Searching OO Associations with RDBMS Persistence Models)

On Tue, 30 May 2006 10:54:52 GMT, David Cressey wrote:

> "Alfredo Novoa" <alfredo_novoa_at_hotmail.com> wrote in message
> news:1148940908.338233.159400_at_j73g2000cwa.googlegroups.com...
>

>>>No, a DBMS is a bucket of bits with some low level rules to manage
>>>those bits.  An OO application provides the beavior that the customer
>>>wants to see.  We can completely eliminate the DBMS and replace it with
>>>another of an entirely different form (non Relational for example) and
>>>still have all the business behavior we need.
>>
>>>The people who sell databases have sold you, and the industry, a
>>>misconception: that the database is the heart of the system.  This is
>>>flawed.  The heart of the system is the application code.  The database
>>>is a detail to be decided at the last possible moment and kept in a
>>>position so flexible that it can be swapped out for another at a whim.

What is the data?

> For 20 years, I believed that the heart of the system was the application
> code. I wrote application code. That's why I believed it. But I've seen
> enough to convince me otherwise in the last 17 years.
>
> Not that I didn't say: "the database". What if we change database vendors?
> Been there, done that.
> What if we rewrite almost all the application code? Been there, done that.
>
> What if we destroy all the data up to this point? Time to update your
> resume, everybody!

But surely you can write your resume again. You can do it in MS-Word, or in a Cuneiform script on clay tablets. No such thing as data, or more generally information exist. There is a beautiful novel of great XX century philosopher S. Lem. All data of humankind were put into a giant DB. The first version of the main index had a size of a house. The secondary index could be kept in a large room. The process of indexing continued until at some point the index had become of one molecule size, so small, that the chief librarian lost it. Humans returned to stone age. Where were the data?

Actually it is funny to see how relational approach intended to *abstract* data away is turning to its antithesis in DB-minds.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de