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In article <39D9EA92.BB0CD2FF_at_edcmail.cr.usgs.gov>,
Brian Peasland <peasland_at_edcmail.cr.usgs.gov> wrote:
> > Well Brian, as much as I appreciate your comments, I have to
disagree here:
>
> I'm always in the mood for a little disagreement....
>
> > Oracle itself has - in co-operation with HP, Compaq and Dell (I
think it was
> > Dell)
> > create a program called database sizer.
> > It works kind of the other way around - you tell the load, and the
program
> > will
> > estimate the h/w (by HP, Compaq - you get the general idea!) needed
to archive
>
> So now I have to disagree with a you a little. The program you are
> talking about (from your description) helps to size the database and
> estimate the hardware. But does it accurately estimate response time
for
> a given query as the original poster suggested? For instance, if I
give
> you a query such as:
> SELECT col1,col2,AVG(col3)
> FROM tableA
> WHERE col1=cond1 AND col2=cond2
> GROUP BY col1,col2
> ORDER BY col1,col2;
> Can you plug in some numbers such as the block size, the buffer cache
> size, etc. and tell me how long it takes to execute this query? I
think
> that this is what the original poster was looking for.
>
> I have no doubts that such a program as you described exists and is
very
> helpful in a variety of situations. But it seems to digress from the
> original post.
>
Yes, these are two very different subjects. But getting back to the
original question, you can't use an excel spreadsheet to determine
query performance. However, you can use tools, such as OEM's
Performance Pack, Quest's SQL Expert, Lecco, TKPROF, set autotrace on,
etc to determine query performance. I've used Performance Pack's Tuning
Pack and I find it very useful. TKPROF has better accuracy however but
it's harder to use. Pick your tradeoffs.
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Received on Tue Oct 03 2000 - 17:16:42 CDT