"Costin Cozianu" <c_cozianu_at_hotmail.com> wrote in message
news:bjqmkq$mburj$1_at_ID-152540.news.uni-berlin.de...
> I don't think "smallest" is good enough , it has to be unique.
>
> Maybe you can derive that the existence of smallest implies uniqueness
> (The examples that I think of where there is no unique set also implies
> there is no smallest).
>
>
> If we pick smallest (vs. unique), then we can have problems, i.e. users
> observe a derived fact, the database chooses the "smallest" update,
> however in reality a "larger" set of facts is true. Then we broke the
> close world assumption: the user might:
> select count(*) ...
> and get the wrong results.
Could you clarify the last paragraph? How can user get wrong count, for
example?
Received on Mon Sep 15 2003 - 16:30:59 CDT
