Re: more on delete from join
Date: Wed, 02 Sep 2009 20:33:01 GMT
Bob Badour wrote:
> That may be how people use views now--I neither know nor have an
> opinion--however, a view is a logical device not a physical device. One
> uses views for logical independence not physical optimization.
To me, logical independence means no logical difference between choices (whether they are physical or logical choices). So if a view is a logical device, I'd ask what logical difference does it make to the results our chosen logic produces, eg. what is the enhancement or increment to the possible logical results? For example, if having the view is convenient in some sense wiithout concern as to the characteristics of the machine or medium (such as an implementation language), I'd say it is an implementation device. I think quite a few people confuse logical device with logical change and mostly what I see in language development (where I've been called a philistine more than once) is just language devices, not logical devices. I'm still using logical devices from forty years ago. Maybe logical independence subsumes physical independence and maybe I'm too old to learn to be a 'typist'! I wouldn't argue with anybody who said a view is language device. Received on Wed Sep 02 2009 - 22:33:01 CEST