Path: newssvr20.news.prodigy.com!newsmst01.news.prodigy.com!prodigy.com!logbridge.uoregon.edu!kibo.news.demon.net!news.demon.co.uk!demon!thewolery.demon.co.uk!thewolery From: "Anthony W. Youngman" Newsgroups: comp.databases.theory,comp.databases.pick Subject: Re: foundations of relational theory? Date: Mon, 27 Oct 2003 00:43:30 +0000 Organization: vinny-puch Lines: 70 Message-ID: <1nOOgDIyoGn$EwYc@thewolery.demon.co.uk> References: <1efdad5b.0309260259.393522ae@posting.google.com> <6db906b2.0310191644.13b47642@posting.google.com> <6db906b2.0310202027.58324c36@posting.google.com> <6db906b2.0310211141.7daf437e@posting.google.com> <6db906b2.0310221139.207ddeb0@posting.google.com> <_Qymb.25414$Fm2.10043@attbi_s04> Reply-To: "Anthony W. Youngman" NNTP-Posting-Host: thewolery.demon.co.uk Mime-Version: 1.0 X-Trace: news.demon.co.uk 1067216571 1026 158.152.222.21 (27 Oct 2003 01:02:51 GMT) X-Complaints-To: abuse@demon.net NNTP-Posting-Date: Mon, 27 Oct 2003 01:02:51 +0000 (UTC) X-Newsreader: Turnpike Integrated Version 5.01 U Xref: newssvr20.news.prodigy.com comp.databases.theory:22127 comp.databases.pick:76516 In article <_Qymb.25414$Fm2.10043@attbi_s04>, Marshall Spight writes >"Bob Badour" wrote in message news:HPudnfvbBOkx4weiU- >KYhw@golden.net... >> "Marshall Spight" wrote in message >> news:MDomb.23527$HS4.91636@attbi_s01... >> >> > One thing this thread has gotten me thinking about is the agility >> question. >> >> Agility is just another word for logical independence. Pick lacks it. > >Well, okay. But do existing DBMSs have complete logical independence? >I think they don't. Views aren't as easy to work with as they need to >be, for example. > > >> [lots of "you can use" statements snipped] >> >> > Relations look like the clear winner to me. >> >> One might use some as yet unidentified structure. Dawn wants to contribute >> something as important as any contribution by Aristotle, Boole or Goedel. >> She is welcome to try. > >Indeed. I don't expect her, or anyone else for that matter, to make >such a discovery. But that doesn't mean the exercise is without >value. For example, Dawn has criticized the fact that in current >practice, it may takes some time for an application programmer >to get a DBA to make a needed schema change. This is a very >real issue that affects me regularly; I'm interested to hear her >take on the issue. Maybe she has useful ideas that will make >this less of a problem. Sack the DBA :-) Pick databases very rarely have a dba looking after them. > >Of course, this issue is one of practice and not one of >foundations, but that's okay. If someone solves this issue >while mistakenly believing it to be a foundational issue, >it is still solved. > >Although I don't believe Dawn will invent a new logical >structure, I could imagine she might come up with something >interesting about schema change management. And even >if she doesn't, that will help me understand the degree of >hardness of the problem, and the degree to which the >problem is fundamental. > >From her and others' posts, it sounds like Pick makes >schema change management easy. I'd like to understand >why: does it come at a cost of expressiveness, is it >a well-designed tool, what? Well, imagine using a SQL table to define another SQL table. (Actually, I think that's a relational requirement, although every relational db I've met has hidden that fact very well). In MV, the FILE definition is just a FILE like any other :-) We just edit the DICT FILE. > >Consider: the fact that Microsoft Access has a crappy >unscalable SQL engine as its core doesn't change the >fact that it has some pretty cool RAD tools. > Cheers, Wol -- Anthony W. Youngman - wol at thewolery dot demon dot co dot uk Witches are curious by definition and inquisitive by nature. She moved in. "Let me through. I'm a nosey person.", she said, employing both elbows. Maskerade : (c) 1995 Terry Pratchett