Re: Guessing?

paul c wrote:

David BL wrote:

It seems to me that every base relvar will in practice have some
defined intensional definition outside the RM formalism and
inaccessible to the DBMS.

A practitioner who (knowingly) tolerates or suggests that is likely either a sucker or a charlatan. (Bob B called Codd's example a straw-man.)

Goedel tells us there will always necessarily be some external intension. However, POOD asks us to minimize it and to render as much of the system as possible amenable to calculation.

Codd's example is a straw man because he omits from the design the information necessary for the dbms to calculate the disjointedness of the base relations.
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Relevant Pages

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  • Re: Guessing?
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