Bob Badour wrote:
> paul c wrote:
>
>> Bob Badour wrote:
>> ...
>>
>>> Any two values of differing most-specific-types are unequal. Thus, if
>>> x and y each have an attribute z where the types are different, the
>>> join will have cardinality zero and will have an attribute z with the
>>> most specific supertype of the z attributes in x and y. This might be
>>> the universal supertype.
>>> ...
>>
>> Thanks very much for that. The word 'if' in 'if x and y each have an
>> attribute ... ' might be at the centre of my question. Will ponder
>> that, it might be the first time that anybody has tried to tell me in
>> terms that I could dig why some OO notions might be important.
>
> Which OO notions would those be?
Inheritance and inheritance.
p
Received on Sun Jul 02 2006 - 21:52:23 CDT
