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Re: Pre-RFC: `unknown` versus `undef`

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From:
Martijn Lievaart
Date:
December 19, 2021 10:01
Subject:
Re: Pre-RFC: `unknown` versus `undef`
Message ID:
2209e5d5-866e-8093-1d85-c8d15fd02d68@rtij.nl
Good thinking points, but:

Op 19-12-2021 om 01:44 schreef Darren Duncan:
> My position is that it is N-valued logic and its arbitrary count of 
> logical dimensions that is the largest problem here.  In general its 
> complexity is exponential, doubling with each new dimension, as each 
> one needs to specifically define its interactions with the others.  
> For example, what does "unknown value" plus "unauthorized" return?
>
...
>
> So rather than treating a singleton unknown as special, the 3-valued 
> logic would treat any instance of Excuse as special, but each reason 
> does NOT add a logic dimension, rather it is just further information 
> "if you want to know".
>

So what does Excuse("unknown value") plus Excude("unauthorized) return? 
You just reintroduced the same problem that made you decide against NVL, 
unless I'm missing something.


HTH,

M4



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