Re: Guessing?
From: paul c <toledobysea_at_ac.ooyah>
Date: Wed, 28 May 2008 02:28:13 GMT
Message-ID: <1r3%j.172402$Cj7.145287_at_pd7urf2no>
>
> Consider the intensional definition :
>
> S = set of surnames of UK prime-ministers after Thatcher
>
> with (current) extension
>
> S = { Major, Blair, Brown }
>
> Only the intensional definition (which is outside the RM formalism) is
> able to tell us how to apply updates over time.
>
> Are you suggesting intensional definitions never exist or sometimes
> don't exist or what?
> ...
Date: Wed, 28 May 2008 02:28:13 GMT
Message-ID: <1r3%j.172402$Cj7.145287_at_pd7urf2no>
David BL wrote:
> On May 27, 9:57 pm, paul c <toledoby..._at_ac.ooyah> wrote:
>> David BL wrote: >> >>> It seems to me that every base relvar will in practice have some >>> defined intensional definition outside the RM formalism and >>> inaccessible to the DBMS. >> A practitioner who (knowingly) tolerates or suggests that is likely >> either a sucker or a charlatan. (Bob B called Codd's example a straw-man.)
>
> Consider the intensional definition :
>
> S = set of surnames of UK prime-ministers after Thatcher
>
> with (current) extension
>
> S = { Major, Blair, Brown }
>
> Only the intensional definition (which is outside the RM formalism) is
> able to tell us how to apply updates over time.
>
> Are you suggesting intensional definitions never exist or sometimes
> don't exist or what?
> ...