Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!wasatch!cs.utexas.edu!uunet!daitc!daitc.daitc.mil From: jkrueger@daitc.daitc.mil (Jonathan Krueger) Newsgroups: comp.databases Subject: Re: Relational Model Keywords: relational empirical support Message-ID: <610@daitc.daitc.mil> Date: 24 Jul 89 20:18:39 GMT References: <18886@sequent.UUCP> <606@daitc.daitc.mil> <220@intek01.UUCP> <19101@sequent.UUCP> Sender: jkrueger@daitc.daitc.mil Reply-To: jkrueger@daitc.daitc.mil (Jonathan Krueger) Organization: DTIC Special Projects Office (DTIC-SPO), Alexandria VA Lines: 31 In-reply-to: normb@sequent.UUCP (Norm Browne) In article <19101@sequent.UUCP>, normb@sequent (Norm Browne) writes: >Does set theory really reflect the real world? [1] Sometimes, in some ways, which are occasionally useful. We could say the same about the integers. When I'm counting cookies and one of them breaks into halves, have we shown how poorly suited integers are for counting real world objects? >Is [set theory] more intuitive? Than what? For what? >What I could not find was substantiation of this (if the theory is >`valid' there should be supporting empirical evidence, otherwise it's >like economics :-) ). Okay, what would you accept as substantiation? If you can't specify what constitutes counterevidence, well, you don't want to be like economics, do you? :-) >[1] Let me give a specific example. Set theory dictates that order is > irrelevant (i.e. unordered sets). What real world application looks > at data [usefully] as unordered? The first thing that is added is > an index which is *NOT* part of set theory! Sorted != ordered != indexed. Grouping != inherent ordering of pairs != access methods. -- Jon --