Re: Examples of SQL anomalies?
Date: Sat, 05 Jul 2008 03:26:42 GMT
Message-ID: <SRBbk.77130$gc5.16927_at_pd7urf2no>
To explain a little more, my point of view is that of somebody who is
interested in the construction of systems. As much as I admire the
efforts of D&D, for their precision, diligence and faithfulness to their
logical principles, I've always been sceptical, for reasons I can't
explain very well, of the practical possibilities for combining a
language that operates on relations with one that allows type definition
by users.
I realize that unlike me, not everybody here has the RM in mind when
they talk about values. But as far as the RM is concerned, I think it
is only concerned with determining equality or inequality of values.
From a practical point of view, I would prefer an engine that uses a
relational language to operate on relations and some kind of type
language (not one of the current OO languages) to define types. I would
hope this would be implemented 'outboard' of a relational engine (or
layer if you like) and use some form of early or late bind to provide
the 'equal' or 'not equal' answers the RM needs. Am sure this must be
extremely controversial to many who know the RM better than I do, as a
change in software could change the facts, eg., the answers a given db