Re: Objects and Relations

From: JOG <jog_at_cs.nott.ac.uk>
Date: 13 Feb 2007 01:49:39 -0800
Message-ID: <1171360179.085930.264280_at_k78g2000cwa.googlegroups.com>


On Feb 13, 1:35 am, "David BL" <davi..._at_iinet.net.au> wrote:
> On Feb 12, 11:49 pm, "JOG" <j..._at_cs.nott.ac.uk> wrote:
>
>
>
> > On Feb 12, 1:35 pm, "David BL" <davi..._at_iinet.net.au> wrote:
>
> > > On Feb 12, 6:35 pm, "JOG" <j..._at_cs.nott.ac.uk> wrote:
>
> > > > On Feb 11, 6:51 pm, "David BL" <davi..._at_iinet.net.au> wrote:
>
> > > > > [snip]
> > > > > It seems entirely immoral to see a set of relations that taken
> > > > > together state facts about both internal and external entities. It
> > > > > seems quite wrong to mix these levels of abstraction. For example,
> > > > > what is a problem domain expert going to think of a query result
> > > > > containing "labels" of parts of the abstract machine (eg StringIds)
> > > > > that they don't know about and don't care about?
>
> > > > "Immoral"? My word, that's a desperate appeal indeed.
>
> > > Desperate?
>
> > > > I have no idea why you think a problem domain expert would be
> > > > concerned with storing strings relationally.
>
> > > That sentence seems a little ambiguous depending on whether
> > > "concerned" is taken in a positive or negative sense. I presume you
> > > meant the negative sense.
>
> > > I'm surprised you say "I have no idea". It seems quite simple to me.
> > > Is there some misunderstanding?
>
> > > Consider a system that has given requirements for storing facts about
> > > external entities. It seems to be a good idea for the relational
> > > schema to be as simple as it can be and no simpler. After all, the
> > > schema represents a rather public part of the system as far as its
> > > design is concerned. The expression of queries and many other things
> > > are schema dependent. Furthermore the schema is something that needs
> > > to be validated against the system requirements with a domain expert,
> > > and domain experts are not always computer literate. For lots of
> > > reasons a simpler schema is better than a complicated one if it meets
> > > the requirements.
>
> > > It seems clear to me that attributes used to store identifiers of
> > > parts of the abstract machine should be avoided in the schema. It is
> > > possible to do this, and it goes part of the way towards ensuring the
> > > schema is as simple as it can be and no simpler.
>
> > > It also seems highly objectionable that someone directly submitting
> > > adhoc queries on the DB would see results that identify entities
> > > inside the abstract machine. I can here the domain expert asking it
> > > now... "WTF is this StringId? What idiot designed this?"
>
> > > > I have no idea why you
> > > > are comparing process-oriented and data-oriented practices.
>
> > > I discussed that in my last post.
>
> > > > And I have
> > > > no idea why you are confusing a mechanism for storing and manipulating
> > > > data, with whether that data is generated from a coder or from the
> > > > outside world. The origin of information is totally irrelevant to the
> > > > principles of good data management.
>
> > > OO is Turing complete. RM+RA+? is also Turing complete. Therefore
> > > we have a basis for comparison; try as you might you can't deny it. We
> > > can look at best practise solutions using the two approaches to see
> > > which is the most natural fit for various problems. Your claim that
> > > they can't be compared is flawed. The measurement exists despite your
> > > philosophical position.
>
> > > > There is a lot of confusion in your line of thought.
>
> > > I don't want to be condescending but I don't believe you are applying
> > > the scientific method. You need to ignore all the metaphysical,
> > > religious, philosophical junk and focus attention on real scientific
> > > conjectures that are falsifiable. It is quite simple. If the
> > > conjecture should be discarded then it's because it doesn't make
> > > predictions at all, or else there exists a good compelling counter
> > > example.
>
> > > The scientific method is not generally based on formally proving a
> > > hypothesis to be true because that is simply not possible in
> > > practise. For example Einstein's GR cannot be proven true. Even
> > > formal systems of mathematics must be accepted on faith. Therefore
> > > stop expecting me to justify the conjecture!
>
> > > Equally important, the scientific method is not based on philosophical
> > > debate. In fact there is only one tool we have to tell the difference
> > > between science and philosophy: the scientific method.
>
> > > A hypothesis is accepted purely on the basis that it is parsimonious,
> > > powerful (ie falsifiable) and no known counterexamples exist.
>
> > > It appears that the computer science industry is filled with
> > > charlatans who don't understand science (nor mathematics for that
> > > matter). I take the view that statements or claims should be tested
> > > for being falsifiable or else don't make them.
>
> > > This newsgroup throws around a number of terms that make me
> > > suspicious. My inclination is to treat the following with extreme
> > > caution: data, information, abstraction, existence, reality, process-
> > > oriented, data-oriented, conceptual layer, logical layer, physical
> > > layer, model, simulation.
>
> > > In a way the insults have been a good thing. I no longer feel at all
> > > concerned with hurting cdt member's feelings. At the start of the
> > > thread I would never have been so bold as to accuse many of you of
> > > lacking science.
>
> > > I realise now I should have gone about things differently, and from
> > > the start of the thread simply said :
>
> > > "Here is the conjecture. It is concise, useful
> > > (if true) and Popper falsifiable. Can anyone
> > > think of a compelling counterexample? Talk
> > > amongst yourselves with your religious beliefs
> > > if you care."
>
> > You forget that hypotheses also have to make some form of cogent sense
> > too. I find the confusion in your post quite astounding. While I do
> > not agree with bob's style, he does seem to have a point.
>
> Let me rewrite the conjecture with all justification stripped away.
>
> 1. In the design entities can be classified as inside or outside the
> abstract machine

RM does not take this view. It is not concerned with 'entities', but facts - propositions composed of roles and values.

> 2. OO objects should only be concerned with implementing entities
> within the abstract machine (ie not representing entities outside)

You seem to have ignored my suggestion to refer to structs, rather than the confusion that is OO.

> 3. RM should only be concerned with representing facts about
> entities outside the abstract machine.

There is not one shred of evidence to suggest that this is a worthwhile statement.

>
> This conjecture is well defined, in the sense that given a particular
> design it is generally possible (in an objective sense) to determine
> whether the conjecture has been met. That is enough to make it
> "cogent".
>
> It also makes it subject to the scientific method because it imposes
> strong limits on what a design is allowed to do. The implicit claim
> is that it doesn't throw out good designs to the extent that all that
> remains are poor designs. Furthermore it doesn't make it more
> difficult to find a good design.
>
> A good scientific hypothesis is characterised by being
> 1) well defined
> 2) concise
> 3) makes strong predictions
> 4) no known counterexample.
>
> Nothing else comes into it.
>
> What do you mean when you say it isn't "cogent"? If you so strongly
> disagree with the conjecture please state the reason in objective
> terms.
>
> > Despite your vitriol, I hope you manage to reconize some of your
> > mistakes in distinguishing different layers and mechanisms yourself,
> > as investigating new ideas is always good. However it seems there is
> > no real discussion to be had with you here.
>
> That may be the case. I hope you don't believe the human mind is
> somehow able to judge "truth" in philosophical matters. Remember how
> you said entities are illusionary and only exist in one's mind? From
> a scientist's perspective that's meaningless.

Simple. First, data management is not 'hard science', it is an engineering problem. Second, there is no way to perform a controlled experiment to prove or disprove your 'conjecture'. Third, there is no physical observation that leads to your 'conjecture', making it handwaving  at best. On top of this,.and as I have stated ad infinitum, your 'conjecture' compares process-oriented and data-oriented mechanisms, apples and oranges. What you present is not 'science' and this is not a cogent debate. Received on Tue Feb 13 2007 - 10:49:39 CET

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