Re: Surrogate Keys: an Implementation Issue

From: Paul Mansour <paul_at_carlislegroup.com>
Date: 24 Jul 2006 06:17:56 -0700
Message-ID: <1153747076.079661.236060@b28g2000cwb.googlegroups.com>

Bob Badour wrote:

> The physical level of discourse deals with physical locations on disk or
> in memory etc. That's what defines it.

<snip>

> I suspect what people refer to as an intermediate level is the external
> physical level of discourse as opposed to the internal physical level of
> discourse.

Bob,

As you noted above, I often perhaps confuse the physical and logical levels. Here is something I've been wondering about. Assume one were to implement the relational model in a high-level intrepreted language, say Lisp, APL, Python, etc. These languages insulate the programmer from the physical level. So it must be possible, if not practical, to implement the RM without ever really thinking about or getting involved in the physical level. So when a programmer is implementing the RM in one of these types of languages, what level is he thinking in or about? Is this what you mean by the "external physical level of discourse"? Received on Mon Jul 24 2006 - 08:17:56 CDT