Path: dp-news.maxwell.syr.edu!spool.maxwell.syr.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!news.glorb.com!news.hub.org!sn-xt-sjc-02!sn-xt-sjc-06!sn-xt-sjc-09!sn-post-sjc-01!sn-post-ams-01!supernews.com!corp.supernews.com!not-for-mail From: Hugo Kornelis Newsgroups: comp.databases.theory Subject: Re: Proposal: 6NF Date: Tue, 10 Oct 2006 01:26:34 +0200 Organization: Posted via Supernews, http://www.supernews.com Message-ID: References: <1160164534.301408.114420@c28g2000cwb.googlegroups.com> <1160244203.847656.254300@e3g2000cwe.googlegroups.com> <1160300704.857861.228120@i3g2000cwc.googlegroups.com> <1160328943.343444.91360@b28g2000cwb.googlegroups.com> X-Newsreader: Forte Agent 1.91/32.564 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Complaints-To: abuse@supernews.com Lines: 29 Xref: dp-news.maxwell.syr.edu comp.databases.theory:45645 On 8 Oct 2006 10:35:43 -0700, Cimode wrote: > >Frank Hamersley wrote: >> Cimode wrote: >> > Frank Hamersley wrote: >> >> Cimode wrote: (snip) >> >>> --it turns out it return 3 out of 4 records --therefore we could >> >>> conclude that the system considers that NULL <> NULL Right? (opposite >> >>> of = should be <> right?) >> >> This is wacky - trying to rationalise 3VL by clutching at 2VL thinking >> >> is very trippy. >> > Trippy? I say Bullshit...Facts are NOT 3 VL. Logically anything that >> > is not = is necessarily different >> >> That is 2VL logic - it is fallacious and it does not apply to a 3VL >> logic domain - period. >Either something equals a value either it differes from it...Are you >saying that 3VL makes the previous statement false? Could you answer >that precise question... Hi Cimode, Yes, 3VL does indeed make the previous statement false. In 3VL, two things can be equal or unequal, but it can also be unknown if they are equal or not. That's the third value in three-valued logic. Best, Hugo