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Re: No exceptions?

From: paul c <toledobythesea_at_oohay.ac>
Date: Thu, 29 Jun 2006 20:19:33 GMT
Message-ID: <pBWog.109359$IK3.48317_at_pd7tw1no> 






J M Davitt wrote:


> paul c wrote:



>> Bob Badour wrote:
>> ...
>>
>>> The way to avoid exceptions is to treat them as compile-time errors.
>>
>>
>> I take it you really mean "ONE way to avoid exceptions ...".  For one 
>> thing, I am interested in being able to express "x join y" in advance 
>> of defining a header for "x" (and I would like to evaluate it as well 
>> if that is logically possible!).
>>
>> p




> 

> This has me scratching my head.  Without a heading, there can be no


> parameters.  Without parameters, there can be no arguments.  Without

> arguments, there can be no quantifiable proposition.  Which leads me

> to, "A relation without a predicate is...  What?"  I find this

> especially curious because you mention the Closed World Assumption

> in the same post.  (Don't forget the Excluded Middle!)

> 

> So, Paul, what are you trying to explore?





Maybe instead of saying "defining a header", I should have said "in 
advance of entering a header".  I had in mind that an "empty" header 
would be assumed.



My peculiar view doesn't require me to ask "what is the predicate of 
such and such a relation".  This will sound ridiculous to most people I 
think because one would ask "well, what good is a database whose 
predicates we don't know?".  OTOH, one aspect that for me defines a 
relational engine is precisely that it must not circumscribe even in the 
most indirect of ways what predicate a particular relation has, its 
whole value is in being to manipulate relations without knowing that - 
otherwise it would be an application!



Apologies if this is metaphysical mumbo-jumbo.  Will ponder the CWA and 
excluded middle again.



p
Received on Thu Jun 29 2006 - 22:19:33 CEST












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