Re: some information about anchor modeling

On 2012-12-05, vldm10 <vldm10_at_yahoo.com> wrote:
> On 2012-11-29, Eric <eric_at_deptj.eu> wrote:
>
>> You are now saying that something is wrong because it is wrong. The
>> concept of the surrogate is not nonsense, you simply do not understand
>> it!
>
>
> In this thread I showed why the surrogate key is a bad solution. See
> my posts from 18 July

I see no point in responding to something I have already responded to!

> and 12 September

This is a couple of examples which are good indicators for the need for a "temporal database", a subject about which there is now a substantial literature which you do not seem to have referred to at any time.

> in this thread. There are many other cases, which show that the surrogate
> key is a bad solution. The cases that I have indicated are very serious.
> As far as I know, this is the first time that someone has explained why
> the surrogate key is a bad solution. This explanation is supported with
> very important examples.

I do not understand why you have made surrogate keys your target, especially as I still think you do not understand them. Where you have raised a real problem it is always about what operations should be allowed in a database and what, if any, record of those operations is kept in the database system. Surrogate keys are neither the problem nor the solution.

> Obviously, RM / T can not support nulls. A person who enters the data
> has to know all the data of the corresponding entity. So, someone could
> set the following question: why RM / T uses binary relations, when data
> entry person has to know the entire entity.

In a system which uses only binary relations there is no such thing as a null, but there is still the possibility of missing/unknown data. The data entry person does not have to know the entire entity.

<snip enormous amount of confused garbage>

>>> I am writing about this, because I have impression that there are people
>>> who try to "fix" RM/T paper, by using works which are done by others.
>>
>> And you object to this? Why?

<snip more stuff which does not answer my question at all!>

> Of course, if you think that my examples are not correct, please post
> it. But please be specific. So, please specify a concrete my example
> which is not correct, and give an explanation. Given that your comments
> were not specific, I can not accept them seriously.

It has taken me this long to make any sense out of your examples at all, and anyway picking on them individually is pointless when you seem to have so many more fundamental confusions. Also, as I said above, your examples do not explain why it is surrogates specifically that are the problem. One might as well claim that you cause car crashes by looking out of a nearby window.

Eric

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