Re: Sets and Lists, again
From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Tue, 23 May 2006 21:11:57 GMT
Message-ID: <xUKcg.12077$A26.287865_at_ursa-nb00s0.nbnet.nb.ca>
Date: Tue, 23 May 2006 21:11:57 GMT
Message-ID: <xUKcg.12077$A26.287865_at_ursa-nb00s0.nbnet.nb.ca>
Gene Wirchenko wrote:
> On 23 May 2006 10:44:59 -0700, "Marshall" <marshall.spight_at_gmail.com>
> wrote:
>
>
>>Gene Wirchenko wrote: >> >>> In short: The order is logical. The index is physical. >> >>The index is derived from the logical order and hence is >>also logical.> and hence is also logical? No, it does not work that way.
>
> Drivel!
>
> The physical implementation is derived from the logical design
Gene, in as much as the rank ordinal is an attribute of the relation, it is logical. It need not map to anything physical. For instance, the data may be stored in any order without affecting the logical attribute.
Even if the rank ordinal is not an attribute of any base relation, it is always possible to derive a relation with a rank ordinal according to some explicit order. Unless you are suggesting that views are physical, I think you are beating a dead horse.
Even Date and Darwen included an operation to treat a relation as an array in Tutorial D. Received on Tue May 23 2006 - 23:11:57 CEST