Re: NULLs: theoretical problems?

Bob Badour wrote:
Keith Duggar wrote:

I'm not trying to have anything. I'm trying to understand what
the "write DEF" prescription buys us over say the "Interactive
Mathematical Proof System" of Farmer, Guttman, and Thayer that
has exactly the property I described that any formula is false
if any variable is NULL. Again, I am failing to grasp what the
"write DEF" prescription buys us. I would like to understand.

KHD

Error detection. It forces one to acknowledge that one understands the
attribute can be undefined and that one is ignoring those propositions
for which it is undefined.

So one kind of error detection it allows is checking that a
user understands an attribute can be undefined? How helpful
would that be in preventing common query errors? Or does it
allow error detection beyond NULL understanding checks?

Thanks for help.

KHD

.

Relevant Pages

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  • Re: NULLs: theoretical problems?
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