Re: SQL query Tuning

PQ values depends on the power of your machine, My experience is that you need minumum 3 cpu's, then having 3 processes/cpu gives you 15 as value, but you can use more ... the power of your machine..

use only parallell on full table scans and multiple cpu hardware, als you need disk configuration that support reading a lot of I/O (no raid5, but stiped or striped miror ...

Erik
Oracle DBA consultant.

ramsunders_at_yahoo.com (R197509) wrote in message news:<1e562f83.0111070035.3c3e5868_at_posting.google.com>...
> erik_at_evd.be (Erik) wrote in message news:<aeb3790f.0111060442.3702b008_at_posting.google.com>...
> > rewrite your statement with
> > select X
> > where
> > WHERE IPAR1.product_range_id > IPAR2.product_range_id
> > union
> > WHERE IPAR1.product_range_id < IPAR2.product_range_id
> >
> > but you have to know how many rows you need about this table when you
> > want to exclude this product_range .....
> >
> > why do you use rule hints ?
> >
> > why not all_rows ?
> >
> > did you already tried select /*+ parallell(ipar1 , 15) */ when you
> > have multiple cpu's ont this machine ...
> >
> > Kind regards
>
> Thank you for your help... I will try out your suggestion of replacing
> the <> with the UNION operation.
> I don't know why the rule hint was used.. as is the case quite often,
> this is something that was developed sometime back and I am trying to
> tune it.. :) I do have replcing it with the ALL_ROWS hint on my To DO
> list...
> I'm not very familiar with the parallel hint.. I mean is there a
> particular type of query that would qualify for using this hint.... or
> is any query parallelizable.... also, what would be an ideal value for
> the degree of parallelism? should I set the degree of parallelism
> equal to the number of CPUs?
Received on Thu Nov 08 2001 - 11:36:16 CET