simple SELECT scales in a multi-processor env?

From: Giovanni Azua <bravegag_at_hotmail.com>
Date: Wed, 19 Feb 2003 16:51:29 +0100
Message-ID: <b309ai$1fnhtn$1@ID-114658.news.dfncis.de>

Hello all,

Imagine you make a costly SELECT statement like this over more than 4 million transactions:

select sum(to_number(amount)) over

       (
             partition by transaction_date
             order by rowid
             range between interval '10' day preceding and interval '10' day
following
       ) as highly_smoothed_amount

from transaction

Oracle implementation of this query is able to transparently spam several threads to execute it and hence use as many processors as possible or this is just executed in the session/connection "primary thread" and the scaling is given by several sessions/connections issuing statements like that...?

My point is: is it paralelism achieved transparently or is something we have to configure and explicitly make happen e.g. creating transaction table as a partitioned table.

Thanks in advance,
Best Regards,
Giovanni Received on Wed Feb 19 2003 - 09:51:29 CST