Re: Conceptual, Logical, and Physical views of data
From: David Cressey <david.cressey_at_earthlink.net>
Date: Wed, 31 Aug 2005 14:50:41 GMT
Message-ID: <5tjRe.4976$FW1.1633_at_newsread3.news.atl.earthlink.net>
Date: Wed, 31 Aug 2005 14:50:41 GMT
Message-ID: <5tjRe.4976$FW1.1633_at_newsread3.news.atl.earthlink.net>
"Dan" <dan_at_nospam.com> wrote in message news:dH2Re.2162$yn2.5505_at_news.uswest.net...
> I thought the 3 layers were:
>
> 1 - The conceptual which deals with end users and client programing.
>
> 2 - The logical that deals with the design on the database and
> maintaining the data.
>
> 3 - Th physical which is how the DBMS stores the data on disk and in
memory.
>
Your level 3 and my Physical view seem about the same to me.
I'm not sure what your level 2 is. For example, if I'm designing an Orace
database, and I decide how big to make a TABLESPACE and what the fill factor
is going to be, is that part of 2 or part of 3?