Re: Definition of reference - was Continuation - An attempt at retriggering thought about past subjects
From: mAsterdam <mAsterdam_at_vrijdag.org>
Date: Thu, 19 Apr 2007 19:52:05 +0200
Message-ID: <4627abb0$0$328$e4fe514c_at_news.xs4all.nl>
>> I hope this may have some usefulness...
>>
>> 1) On a better formalization of reference definition, (subjects
>> launched by Marshall)..I we came to the following formalization...
>> (using math symbology I apologize in advance for being too terse)...
>>
>> --Reference
>> R(a) レ S(b) ≡∀a E R,∀R(a): ∃b E S | ∃S(b) | a=b
>> --Reference Unique
>> R(a) ル S(b) ≡∀a E R,∀R(a): ∃!b E S | ∃!S(b) | a=b
>>
>> --> QUESTIONS: Do this still seem correct ?(In other words could it be
>> refined/improved) what could be the next step onto using that
>> definition?
Date: Thu, 19 Apr 2007 19:52:05 +0200
Message-ID: <4627abb0$0$328$e4fe514c_at_news.xs4all.nl>
Jonathan Leffler wrote:
> Cimode wrote:
>> I hope this may have some usefulness...
>>
>> 1) On a better formalization of reference definition, (subjects
>> launched by Marshall)..I we came to the following formalization...
>> (using math symbology I apologize in advance for being too terse)...
>>
>> --Reference
>> R(a) レ S(b) ≡∀a E R,∀R(a): ∃b E S | ∃S(b) | a=b
>> --Reference Unique
>> R(a) ル S(b) ≡∀a E R,∀R(a): ∃!b E S | ∃!S(b) | a=b
>>
>> --> QUESTIONS: Do this still seem correct ?(In other words could it be
>> refined/improved) what could be the next step onto using that
>> definition?
> > I'm lost - please can you explain the squiggles (between R(a) and S(b) > on the LHS of the equivalence) and the E, the !b and the !S(b)? Without > knowing what those are, there is no way to answer your question.
http://groups.google.nl/group/comp.databases.theory/msg/45c631ac7b31ffc7 Received on Thu Apr 19 2007 - 19:52:05 CEST