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Re: Counting propositions

From: Tony <andrewst_at_onetel.net.uk>
Date: 18 Jun 2004 01:56:18 -0700
Message-ID: <c0e3f26e.0406180056.7acb4e54@posting.google.com>


"Alan" <alan_at_erols.com> wrote in message news:<2jecrrF10qrcbU1_at_uni-berlin.de>...
> Now _there's_ great example of bottom posting...
>
>
>
> "Tony" <andrewst_at_onetel.net.uk> wrote in message
> news:c0e3f26e.0406171213.73e101f7_at_posting.google.com...
> > "x" <x-false_at_yahoo.com> wrote in message
> news:<40d1ac45_at_post.usenet.com>...
> > > **** Post for FREE via your newsreader at post.usenet.com ****
> > >
> > >
> > > "Tony" <andrewst_at_onetel.net.uk> wrote in message
> > > news:c0e3f26e.0406170609.39c1b7bd_at_posting.google.com...
> > > > "x" <x-false_at_yahoo.com> wrote in message
> news:<40d16fd6_at_post.usenet.com>...
> > > > > **** Post for FREE via your newsreader at post.usenet.com ****
> > > > >
> > > > >
> > > > > "Tony" <andrewst_at_onetel.net.uk> wrote in message
> > > > > news:c0e3f26e.0406170106.2e3f34ac_at_posting.google.com...
> > > > > > "x" <x-false_at_yahoo.com> wrote in message
> news:<40d02f27_at_post.usenet.com>...
> > > > > > > **** Post for FREE via your newsreader at post.usenet.com ****
> > > > > > >
> > > > > > >
> > > > > > > "Tony" <andrewst_at_onetel.net.uk> wrote in message
> > > > > > > news:c0e3f26e.0406160241.31623d1c_at_posting.google.com...
> > > > > > > > "x" <x-false_at_yahoo.com> wrote in message
> news:<40cf02c7$1_at_post.usenet.com>...
> > > > > > > > > **** Post for FREE via your newsreader at post.usenet.com
> ****
> > > > > > > > >
> > > > > > > > >
> > > > > > > > > "Tony" <andrewst_at_onetel.net.uk> wrote in message
> > > > > > > > > news:c0e3f26e.0406150554.6822ed6f_at_posting.google.com...
> > > > > > > > > > "x" <x-false_at_yahoo.com> wrote in message
> news:<40cecf85_at_post.usenet.com>...
> > > > > > > > > > > **** Post for FREE via your newsreader at
> post.usenet.com
> ****
> > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > > > "Tony" <andrewst_at_onetel.net.uk> wrote in message
> > > > > > > > > > > news:c0e3f26e.0406150222.fe2eea5_at_posting.google.com...
> > > > > > > > > > > > "x" <x-false_at_yahoo.com> wrote in message
> news:<40ce9db7_at_post.usenet.com>...
> > > > > > > > > > > > > Ok. But why there is a need to know this number ?
> > > > > > > > > > > > > It is like saying "today I made 100 affirmations".
> > > > > > > > > > > >
> > > > > > > > > > > > Have you never wanted to know how many of something
> you
> had?
> > > > > Can
> > > > > you
> > > > > > > > > > > > not envisage a large business wanting to know, for
> example,
> > > > > how
> > > > > many
> > > > > > > > > > > > employees it has?
> > > > > > > > > > >
> > > > > > > > > > > Employees yes. Propositions no.
> > > > > > > > > >
> > > > > > > > > > Very droll ;-)
> > > > > > > > > >
> > > > > > > > > > But the fact is that from the N propositions we have that
> say
> > > "We
> > > have
> > > > > > > > > > an employee named xxx with salary yyy ...", we can deduce
> the
> useful
> > > > > > > > > > fact that we have N employees - simply by counting the
> propositions.
> > > > > > > > >
> > > > > > > > > What made you so sure.
> > > > > > > >
> > > > > > > > What makes you so unsure? Are you making some kind of
> philosophical
> > > > > > > > point that I'm not getting?
> > > > > > >
> > > > > > > Well, because you don't directly count employees, but you count
> propositions
> > > > > > > about employees instead, it is a legitimate question to ask if
> the
> result is
> > > > > > > accurate and why.
> > > > > > >
> > > > > > > Other reasons:
> > > > > > > - the database may contain propositions about past, current and
> future
> > > > > > > employees
> > > > > > > - the database may contain propositions about employees in
> different
> > > > > > > relations (or relvars)
> > > > > > > - it might be hard to distinguish propositions about employees
> from
> other
> > > > > > > propositons in the database
> > > > > >
> > > > > > Well, you ceertainly have to know what the propositions mean
> before
> > > > > > you can get a meaningful answer by counting them. If the
> propositions
> > > > > > include past and future employees then you should ensure that you
> only
> > > > > > count the propositions about current employees by adding the
> > > > > > appropriate WHERE clause.
> > > > > >
> > > > > > It shouldn't be at all hard to distinguish propositions about
> > > > > > employess from other propositions in the database, because a
> > > > > > relation/table must only hold propositions of one type.
> > > > >
> > > > > So you say that the employees are in *one-to-one correspondence*
> with
> the
> > > > > propositions about employees, or something like that and this is the
> reason
> > > > > you can count propositions to determine the number of employees ?
>
> > > > I do, though I sense I may be walking into a trap ...
>
> > > :-)
>
> > > > I guess the term "external predicate" comes in here, i.e. the
> > > > knowledge that these propositions EACH ??? assert the employment of 1
> > > > employee is implicit.
> > >
> > > 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.
> >
> > > > From that, one can deduce that the existence of
> > > > N propositions implies the existence of N employees.
> > >
> > > 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.
> >
> > > Why do you insist in counting the propositions, for counting the
> employees
> > > then ?
> >
> > Because it works? ;-)

... yes, isn't it just! Received on Fri Jun 18 2004 - 03:56:18 CDT

Original text of this message

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