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Home -> Community -> Usenet -> comp.databases.theory -> Re: What to call this operator?
Mikito Harakiri wrote:
> "there exists employee x and department y such that x works in y
> AND
> there exists department y and manager z such that y is led by z"
>
> which can be reduced to
>
> "there exists employee x, department y, and manager z
> such that x works in y and y is led by z"
Quantifies are subtle entities. I don't think
"there exists employee x and department y such that x works in y
AND
there exists department v and manager w such that v is led by w"
is logically equivalent to
"there exists employee x, department y, and manager z such that x works in y and y is led by z"
I renamed bind variables in the second half of the first sentence to make this obvious. Received on Fri Jul 01 2005 - 13:18:42 CDT