Re: Question on Structuring Product Attributes

Further to:

> On Tuesday, 25 February 2014 20:34:37 UTC+11, Derek Asirvadem wrote:
> Eric
>
> > So tell me, in as few sentences as possible, what *you* think the Null
> > Problem is.
>
> I don't have one. I can't define what I do not have. I have implemented close to eighty full databases in 34 years that do not have it, and any code written, even after I left will not have it.

I don't believe in private definitions. I accept the concept of Authority. Feel free to supply an authoritative definition (that excludes wiki).

> (I have written about it scores of times, please google. IIRC there is a loooong thread somewhere here with a self-styled "academic" about the virtues of 3VL, multi-VL and braised VL. If you are genuinely interested in having the alien problem removed from your mind, as opposed to merely arguing about how everyone should have the disease, please open a new thread and email me.)

I found another recent post, ie. with someone else, not a self-styled academick. https://groups.google.com/d/msg/comp.databases.theory/Gphu01jz4H0/DOLjN-gm_l4J

Further to:

> > > Those who demand that the physical implementation must be limited to
> > > the limitations of the abstract, are lunatics.
> >
> > The physical layer can do whatever the hell it likes, as long as it can
> > produce correct results efficiently enough. However it is supposed to
> > have an interface limited to the abstract model being supported (in this
> > case, Relational Theory). There are two levels here, and those who
> > cannot distinguish them are very wrong. This does not imply lunacy.
> > Unfortunately you seem to be one of those who fails to make the
> > distinction.
> >
> Well, that sounds like a disagreement, not that either [one or the other] is *proved* "right" or "wrong". And the proof for the latter is not going to happen in this medium.
>
> The people who have laboured over that entire issue for the last forty years will appreciate that. Those who have decided that that limitation is a stupid limitation, and have dispensed with it, have created reliable platforms. Those who think as you do (seduced by the "books" by "academics" and "mathematicians", no doubt), are still writing, their platforms are unfinished, and a labour to use. Visit HeyPrestoTheThirdManifesto for a veritable orgy of that kind of insanity.
>
> Another way of stating that is this. Lunatics cannot abide us *not* submitting to their absolute demands on our thinking. They want us to be like them, to think like a lunatic, otherwise it scares the bejeezus out of them. That is why they should be locked up, they infect humans. If a human can, then there is nothing wrong with a physical layer that is not completely limited to the abstract layer, that goes beyond it. Of course, it can't be allowed to break rules that are defined in the abstract layer, that is a different thing, constraints, as opposed to limitations.

I don't know if you will agree, but I think the Null Problem is a good example to clarify (prove?) this issue of the delta between the abstract and physical layers.

The abstract-only thinkers, who have the Null Problem firmed lodged in their minds, along with schizophrenia and fear of the sky falling in, think the Null problem is real. I agree that the Null Problem exists in the abstract layer. They forget that it is abstract (typical schizophrenics, one part of their mind battles with another part of their mind). So far, we do not have a problem, insanity is constrained to the institutions, and not inflicted on us.

But they forget that they have no skills or knowledge of the physical layer, of the universe, of reality (they are abstract). In the self-obsessed grandeur of their mirror, they demand that those with skills and education re the physical layer submit to the insanity of their abstract layer.

Now we do have a problem. The high-end vendors, and those with genuine engineering qualifications, see the problem for what it is. They politely thank the abstract-thinkers for their marvellous contribution to society; they determine which abstractions are valid (that do apply to reality, the physical plane); they implement those; and they jettison the rest, along with demands to prevent the sky from falling in.

That means the high-end vendors and the capable implementers do not have the disease of the Null Problem, but the abstract thinkers do have it.

That means the physical layer is not limited to (or governed by) the abstract model.

The physical layer is governed by the laws of the physical universe. Period. Full stop. End of story.

--

Sure, the better physical implementations are the result of modelling at the logical level, and that is a demand if standards are practised.  But standards are not followed by everyone, logical modelling is not an absolute requirement.  Millions of people build mud huts and call them houses, homes, and that is not limited to Africa and India, it is in your neighbourhood.

Further, within the logical level, there are levels, or different modelling methods.  Given that the difference between the physical and the logical is at least one layer of abstraction, each of those methods represent further layers of abstraction, of different forms of abstraction.

Some of those layers of abstraction are valid; some of the valid ones have methods; others are valid but devoid of methods, and are therefore useless (a waste of time to discuss, but may be worthy of noting); others are invalid; others still, are simply insane.

If your task is to implement the physical, sure, evaluate the several abstract layers available, and choose carefully.  Choose one layers for the logical that is appropriate.

That means, for qualified people, the physical will not have the Null Problem or code to prevent the sky from falling in.

Do not hire anyone for a physical implementation who elevates the abstract above the laws of the physical universe.  If you do, you will have, implemented in the physical, things that do not need to exist in the physical plane, but are dear to the hearts of abstract thinkers:
- the Null Problem
- method to prevent the sky falling in
- "transactions" that take hours, and require a transaction log that is twice the size of the database that is being updated
because to those creatures, the physical layer "should" be able to cope with, and must be subordinate to, the abstract layer, which is very "real" to them.  it isn't real to us. 

-- 

Another example.  The OO types have one and only one form of abstraction: OO.  Without exception, every single "database" they produce is a disaster, an abortion, a crime against nature.  They suffer from the same mental disease that you propose.  Ok, don't call it lunacy or insanity, call it what you will, but it is a form of thinking that is so narrow in scope, that it is far below the capability of a normal human being (ie. IQ between 90 and 110).  They have the grandest computer systems and modelling tools, but they produce only mud huts.  Each with multiple storeys, and hundreds of rooms, veritable mansions of mud.  

They are so attached to the disease, and so incapable of understanding the problem (denial?), that they invent flavours of the disease, and names for them, clueless that others are immune to the disease: Object-Relational Impedance Mismatch.  All of this merely contributes to making real, something that is not real (so they have to create it by decree); implementing an abstraction which is invalid on the physical plane; validating their mad fantasy.  It would be funny if it were no so sad.

They have to invent new methods of handling mud, the disease that normal humans do not have: Re-factoring.  Genuinely capable implementers do not need it.  First they give you the disease, and then they give you the balm (it is not a cure) for it.  

Those of us who refuse to swallow the disease, or who are immune to it, do not suffer the disease and the painful consequences, and do not need the balm.  We are not cured, we are immune.

Cheers
Derek