Re: A pk is *both* a physical and a logical object.

Brian Selzer skrev:

> The schema of a database describes a set of possible database values, each
> of which represents a complete description of a situation that may occur,
> and the body of a database, the actual database value, represents a complete
> description of the situation that is actually occuring. In this context, a
> world is a situation, an instance of the universe--a particular set of
> circumstances that can or do obtain. An update clearly designates which of
> the possible database values is now the actual database value, and since
> there is a bijective mapping between the set of all possible database values
> and the set of all possible worlds, it stands to reason that an update
> causes a possible world to become the actual world.

I guess next you are going to tell us that nulls are really an attempt at modelling quantum physics. Or was that transactions?

Nis Received on Thu Jul 19 2007 - 08:26:55 CDT