Re: Accessing local database using a dblink in Oracle 9i/10gR2

From: saurangshu <saurangshu_at_gmail.com>
Date: Thu, 3 Jan 2008 19:05:22 -0800 (PST)
Message-ID: <e362772b-8c23-4e6b-82dd-ef22a724643a@e10g2000prf.googlegroups.com>


On Jan 4, 3:01 am, hpuxrac <johnbhur..._at_sbcglobal.net> wrote:
> On Jan 3, 2:10 pm, saurangshu <saurang..._at_gmail.com> wrote:
>
>
>
> > Hi DB Gurus,
>
> > I have an application which tries to access data from more than one
> > identically structured databases. Each of the databases has the same
> > table with different data which the application reads and tries to
> > store in a single repository. Moreover, the source tables can be big
> > at times having three millions or more rows. Now, the application
> > reads data from the remote databases using a dblink created in the
> > runtime. The problem comes when the data source is in the target
> > database instance where the application will have to create a dblink
> > pointing to the local instance itself.
>
> > Does anyone knows about any performance problem in accessing the local
> > data using the dblink? I have tried to check the explain plan but the
> > cost seems to be identical for a dblink or a direct access for small
> > tables. Is there any way to check the performance in this case?
>
> > Thanks,
> > Saurangshu
>
> Why don't you have a double check where you see if the link name you
> are going to dynamically create is the same as your local instance and
> then bypass that overhead?

Hi,

I will really like to build a logic like that if I know some known performance problem with this approach of accessing the local data through the dblink. Do you know of any such known issues?

Thanks for your suggestion,
--saurangshu Received on Thu Jan 03 2008 - 21:05:22 CST

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