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

From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Tue, 30 May 2006 22:31:10 GMT
Message-ID: <OI3fg.15244$A26.356280_at_ursa-nb00s0.nbnet.nb.ca>


Joe Van Dyk wrote:

> Alfredo Novoa wrote:
> 

>> Robert Martin wrote:
>>
>>>>> The big problem with OO and RDB is that people try to make them
>>>>> represent each other. RDB is about data structure an OO is about
>>>>
>>>> behavior structure.
>>
>>>> No no no! RDB is about data management and OO is about application
>>>> programming.
>>
>>> That's what I said. This shows profound ignorance of Thesauri.
>>
>>>> The DBMS must enforce all the business rules (data behavior). The OO
>>>> applications must enforce the presentation and communication behavior.
>>
>>> Nahhh. The DBMS must store the data, manage the queries, and enforce
>>> some integrity rules. Business rules are in the domain of the
>>> application. We don't want the business rules being done by the
>>> database. What if we replace the database vendor? Must we rewrite all
>>> the business rules?
>>
>>>>> The objects in the OO program should MANIPULATE the
>>>>> data structures from the RDB.
>>
>>>> Very wrong. The OO program should TRANSFORM the user input in orders
>>>> for the DBMS.
>>
>>>> The OO program is an interface between the users and the DBMS. A
>>>> friendly substitute for the DBMS console.
>>
>>> 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.
>>
>> If the mentors are like this, I don't want to imagine the rest.
>>
>> Regards
>> Alfredo
>
> Hm, I take it you're not a big fan of the Active Record pattern?

Only a complete idiot would be. "Let's take something with the full power of predicate logic and leave it with, um, restriction. Yeah, that'll bring it down to the level we want!" Received on Wed May 31 2006 - 00:31:10 CEST

Original text of this message