Re: teaching relational basics to people, questions

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 - 21:33:36 CET