Re: Surrogate Keys: an Implementation Issue
From: Brian Selzer <brian_at_selzer-software.com>
Date: Sun, 30 Jul 2006 17:32:42 GMT
Message-ID: <_26zg.74003$fb2.70061_at_newssvr27.news.prodigy.net>
>> "paul c" <toledobythesea_at_oohay.ac> wrote in message
>> news:zTOyg.269253$IK3.233927_at_pd7tw1no...
>> There can be no discussion without time. Relational assignment cannot
>> exist without the concepts of before and after. And the truth of a
>> statement belonging to the database state that existed before an
>> assignment depend on the circumstances that obtain before the assignment,
>> which may no longer remain after.
Date: Sun, 30 Jul 2006 17:32:42 GMT
Message-ID: <_26zg.74003$fb2.70061_at_newssvr27.news.prodigy.net>
"paul c" <toledobythesea_at_oohay.ac> wrote in message news:yw4zg.281148$IK3.258613_at_pd7tw1no...
> Brian Selzer wrote:
>> "paul c" <toledobythesea_at_oohay.ac> wrote in message
>> news:zTOyg.269253$IK3.233927_at_pd7tw1no...
>>> Brian Selzer wrote: >>>> "paul c" <toledobythesea_at_oohay.ac> wrote in message >>>> news:g9Nyg.263082$iF6.250988_at_pd7tw2no... >>>>> Brian Selzer wrote: >>>>>> What's the point of a database if it doesn't reflect some aspect of >>>>>> reality. ... >>>>> To talk precisely about whatever we want to talk about. Nothing more. >>>>> Doesn't need to be real. >>>>> >>>> Agreed. But even a conceived universe subsumes certain absolutes, such >>>> as time. >>>> >>> In that case, the statements in the database should talk about time, >>> ie., aspects of time. These are different from statements about the >>> time it takes the database to say something. >>> >>
>> There can be no discussion without time. Relational assignment cannot
>> exist without the concepts of before and after. And the truth of a
>> statement belonging to the database state that existed before an
>> assignment depend on the circumstances that obtain before the assignment,
>> which may no longer remain after.
> > No, it doesn't depend on 'circumstances'. Assuming variables, as you are, > the truth of a statement depends on the value of the relation that is > assigned to a variable. >
> p Received on Sun Jul 30 2006 - 19:32:42 CEST