Re: Question on Structuring Product Attributes
From: Jan Hidders <hidders_at_gmail.com>
Date: Tue, 1 Oct 2013 13:59:46 +0200
Message-ID: <524ab932$0$3170$e4fe514c_at_dreader36.news.xs4all.nl>
>
> James said that SQL was intended to be a language for deriving logical
> inferences.
>
> Rob said that saying this required "great poetic license".
>
> I suggested that there is evidence to the contrary.
>
> Where is the absurdity?
>
>
> You are making this up (and most of the rest of it) to support your own
> rather strange viewpoint.
>
> snip ><
>
>
> 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.
>
> snip ><
>
>
> So tell me, in as few sentences as possible, what *you* think the Null
> Problem is.
>
> While you are at it, tell me what Oracle "features" show that it can "do
> the Null Problem Really Well".
>
> And finally, people can disagree with you, and even be wrong in doing
> so, without being lunatics, or insane, or abnormal.
Date: Tue, 1 Oct 2013 13:59:46 +0200
Message-ID: <524ab932$0$3170$e4fe514c_at_dreader36.news.xs4all.nl>
On 2013-09-30 20:41:41 +0000, Eric said:
> On 2013-09-30, Derek Asirvadem <derek.asirvadem_at_gmail.com> wrote:
>> On Monday, 18 February 2013 09:09:15 UTC+11, Eric wrote: >>> On 2013-02-17, Rob <..._at_gmail.com> wrote: >>>> On Saturday, February 16, 2013 4:20:01 PM UTC-7, paul c wrote: >>>>> On 14/02/2013 8:03 PM, James K. Lowden wrote: >>>>>> SQL was intended, I'm sure you agree, to be a language for deriving >>>>>> logical inferences. >>>>> [omitted text]. >>> >>> [more omitted text] >>> >>>> Database technology has come a long way since the 1970s when SQL >>>> was initially specified, and relational DBMSs do alot more than >>>> report-writing. But to suggest that in the 1970s, the authors were >>>> interested in "logical inference" requires great poetic license compared >>>> to "replacing the report-writer capabilities of IMS", and feels like >>>> history rewritten. >>> >>> To quote from Codd[1970]: >>> >>> "The adoption of a relational model of data, as described above, >>> permits the development of a universal data sublanguage based on an >>> applied predicate calculus. A firstorder predicate calculus suffices >>> if the collection of relations is in normal form." >>> >>> I rather think there is a connection between "predicate calculus" and >>> "logical inference", yes? So perhaps they should have been interested. >> >> The point is absurd.
>
> James said that SQL was intended to be a language for deriving logical
> inferences.
>
> Rob said that saying this required "great poetic license".
>
> I suggested that there is evidence to the contrary.
>
> Where is the absurdity?
>
>> Rob's point (as I see it) is that the asylum dwellers rewrite history, >> as they often do. Charging either the System R team, or the Sequel Team, >> or the SQL Committee (of old, before they were subverted), with having >> missing something that is relevant today, which was not a criterion in >> the 1970's, is simply dishonest.
>
> You are making this up (and most of the rest of it) to support your own
> rather strange viewpoint.
>
> snip ><
>
>> 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.
>
> snip ><
>
>> But 30 years after the null problem was resolved, ...
>
> So tell me, in as few sentences as possible, what *you* think the Null
> Problem is.
>
> While you are at it, tell me what Oracle "features" show that it can "do
> the Null Problem Really Well".
>
> And finally, people can disagree with you, and even be wrong in doing
> so, without being lunatics, or insane, or abnormal.
Let me chime in here.
Derek, you and I probably share many points of view and are probably fighting the same fight debunking dbdebunk, but I'm not cool with your aggressive wording and think it is counterproductive.
- Jan Hidders