Date's First Great Blunder
Date: Tue, 13 Apr 2004 22:11:18 -0500
Message-ID: <c5ia56$t04$1_at_news.netins.net>
C. J. Date has written about what he calls "The First Great Blunder" related to this question: What concept is it in the relational world that is the counterpart to the concept of object class in the object world?
He suggests that there are two answers given: domain = object class or relvar = object class. He then says that the first equation is obviously right and the second wrong. Classes are types and domains are types, but relvars are variables and, therefore, not types, so QED.
The idea, it seems, is to rid Java programmers of the notion of using classes to define "relations" or records. I'm guessing I'm not the only one who doesn't buy Mr. Date's argument.
I'll toss out one of the way-too-many-thoughts buzzing in my head on this topic. How about this equation:
Class = Metadata
A class is a spec/template -- not a variable nor an object. There can be metadata for a type and metadata for a relation/record and classes corresponding to either.
Do many folks agree with Date on this point or is this one of his lone-ranger attempts to push against the OO folks? --dawn Received on Wed Apr 14 2004 - 05:11:18 CEST