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Home -> Community -> Usenet -> c.d.o.server -> Re: Designing database tables for performance?
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?
Physical IO means that IO have some physical inmemory/hd counterpart while logical IO mean *no media* at all as a prerequisite.
> From Oracle's point of view, if the desired data exists in
> Oracle's buffers, that is a logical I/O.
As I said, I am well aware of ORACLE brainwashing over its troops.
ORACLE succeded to convince the audience of practictionners that RAM
(call it cache if you want) = logical. One of Larry Ellison
*contribution* to the field of database technology. Reading and
educating yourself in RM will help you see the absurdity in that. (See
rule of indepedence netween logical and physical layer)
[Snipped Description of process - thanks for the pedagogic intent
though]
>
> Now, you are welcome to think it is better to be more simple than that
> and just say RAM I/O is the same as HD, but that sounds patently
> absurd to me. Perhaps you have a better way of distinguishing the
> semantics?
It sounds absurd because Larry Ellison has brainwashed people like you
(no disrespect meant) *not* to think otherwise to boost up his
products sales and bank account. Read books written by knowledgeable
audiences about RM and you will see what I am refering to.(was in your
shoes once long ago;)) A few good books to read that may help...
http://www.dbdebunk.com/books.html Received on Sat Feb 24 2007 - 07:30:20 CST
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