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Re: Counting propositions

From: x <x-false_at_yahoo.com>
Date: Thu, 17 Jun 2004 13:22:12 +0300
Message-ID: <40d16fd6@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 ****
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> > "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>...
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> > > > "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
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> > > > > > "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 ?

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Received on Thu Jun 17 2004 - 05:22:12 CDT

Original text of this message

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