Re: teaching relational basics to people, questions

From: paul c <toledobythesea_at_oohay.ac>
Date: Sat, 28 Nov 2009 20:33:36 GMT
Message-ID: <AOfQm.53861$Db2.3195_at_edtnps83>



Mr. Scott wrote:
...
> But what if there is more than one row? The information content of a table
> is the logical sum (disjunction) of the information represented by each row.
...

The conventional view is that is that the information in a table is the logical conjunction of the information represented by the rows in the table. Just because the table is formed by a summing operation doesn't change that.

...
> But those can easily be transformed into into truth-valued constraints,
> can't they?
> ...

Not easy if users aren't required to know default values. I don't see why they should. Contrary to Dr. Strangelove, the whole point of defaults is to avoid users having to know them! Received on Sat Nov 28 2009 - 14:33:36 CST

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