RE: Is there a way to force P->S for a DFO?

Regards

Alex

-----Original Message-----
From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Jonathan Lewis Sent: Thursday, July 25, 2013 12:12 PM
To: oracle-l_at_freelists.org
Subject: Re: Is there a way to force P->S for a DFO?

There may be a more efficient option, but if all else fails

a) write the query block that you want to run in parallel - check its path
b) add a "rownum r" to the select list - check the path
c) make this an inline view and join to the rest of the tables - if necessary with a no_parallel hint for every table.

The rownum should result in a VIEW operator appearing in the plan - with a parallel path to generate the view data, but a serial path as the view result set is used.

Regards

Jonathan Lewis
http://jonathanlewis.wordpress.com/all-postings

Author: Oracle Core (Apress 2011)
http://www.apress.com/9781430239543

• Original Message ----- From: <alexandr.antonov_at_barclays.com> To: <oracle-l_at_freelists.org> Sent: Thursday, July 25, 2013 11:15 AM Subject: Is there a way to force P->S for a DFO?

| Hi list
| I've got a large fact table and kind of snowflaked dimensions. I need to
go from one dimension through fact into the other dimension. I'm trying to write a query which reads the corresponding partition of the fact, extracts the list of join keys, materialises this result set, and finally joins the necessary dimensions. The key thing I'm trying to do is to run the initial query on the fact in parallel and then the rest of the query serially. In other words I need to run one DFO in parallel and the other serially. Now with the last bit I'm stuck and can't find the way to do it. Does anyone know if that's possible at all?
| I'm using Oracle 11.2.0.3 on Linux x64.
|
| Thanks for any help
|
|
| Alex
|
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This message is for information purposes only, it is not a recommendation, advice, offer or solicitation to buy or sell a product or service nor an official confirmation of any transaction. It is directed at persons who are professionals and is not intended for retail customer use. Intended for recipient only. This message is subject to the terms at: www.barclays.com/emaildisclaimer.

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