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Re: Designing database tables for performance?

From: Cimode <cimode_at_hotmail.com>
Date: 6 Mar 2007 12:52:13 -0800
Message-ID: <1173214333.040736.29540@q40g2000cwq.googlegroups.com>


On 6 mar, 05:59, "d..._at_smooth1.co.uk" <d..._at_smooth1.co.uk> wrote:
> On 24 Feb, 13:30, "Cimode" <cim..._at_hotmail.com> wrote:
>
> > On 23 fév, 22:33, "jgar the jorrible" <joel-ga..._at_home.com> wrote:
>
> > > > In what RAM would be less physical than HD ? For any reason, an
> > > > absurdity is an absurdity.
>
> > > Not an absurdity, you just aren't paying attention to how the I/O is
> > > counted.
>
> > So you say there are *ways* to count IO's. Fair enough. Question is:
> > what has the way of counting IO's has any bearing on the media that
> > supports them and therefore qualifies their nature as physical or
> > logical? What is the difference: speed?
>
> Yes. A logical I/O does not go down an I/O channel but comes via the
> memory bus.

And in what a memory bus is less *physical* than an IO channel? How do you think such bus is filled with data at some point in time otherwise than by a pull on the IO channel.

> The time to complete is therefore far less and the "cost" in terms of
> time is much less.

So because time is the difference that makes less physical. Don't you see anything wrong in that? Received on Tue Mar 06 2007 - 14:52:13 CST

Original text of this message

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