Re: more on delete from join

From: Marshall <>
Date: Wed, 2 Sep 2009 08:12:02 -0700 (PDT)
Message-ID: <>

On Sep 2, 2:44 am, "Joe Thurbon" <> wrote:

> So, to update a view, rather than update the conclusion directly, one must  
> update (one of) the base relvars that are used to derive the  
> conclusion/view. That is abductive.

I guess I see what you mean, but strictly speaking it doesn't seem to fit the definition. In abductive reasoning, one knows a -> b, and b, but one doesn't know that it was in fact a that implied b. Whereas with a view, we do know.

Marshall Received on Wed Sep 02 2009 - 10:12:02 CDT

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