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Re: Counting propositions

From: x <x-false_at_yahoo.com>
Date: Fri, 18 Jun 2004 09:56:39 +0300
Message-ID: <40d29127$1@post.usenet.com>

"Tony" <andrewst_at_onetel.net.uk> wrote in message news:c0e3f26e.0406171213.73e101f7_at_posting.google.com...

> > You see, there are propositions that assert the employment and
propositions
> > that assert other things about the employee.
>
> Yes - like a table of employee_salary_history may assert 7 facts about
> 1 employee. But I know that, because an employee is identified by
> Emp_id (or whatever), and this table of propositions is not.

Funny that you mentioned Emp_id. :-)

You see, there might be a relational database that has no named relation/relvar that (directly) assert employment.

Like:

involved_in(Emp_id, Proj_id)
manage(Emp_id, Proj_id)

> > Not true. There might be more propositions per employee (without
> > duplicates).
>
> Not in the table of propositions that has Emp_ID as the key there
> can't be.

 It is possible to have no such table or serveral overlapping tables.

> > Why do you insist in counting the propositions, for counting the
employees
> > then ?
>
> Because it works? ;-)

It works only when you count Emp_IDs, not the propositions employing Emp_IDs :-)

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Received on Fri Jun 18 2004 - 01:56:39 CDT

Original text of this message

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