Re: Database Link Question (For Guru)!

From: Brian Peasland <peasland_at_edcmail.cr.usgs.gov>
Date: Thu, 24 Aug 2000 13:01:23 GMT
Message-ID: <39A51CA3.8EE2C840@edcmail.cr.usgs.gov>

> That's a simple one.
> AFAIK, doing joins will kill your network,
> as all of the remote data is sent over, the join
> is done locally. Think of introducing views on the remote

Generally, the join is done locally which means that the remote tables involved in the join must be brought through the network in order to participate in the join. But this is not always the case, especially if the DRIVING_SITE hint is employed. And you don't always have to retrieve the entire remote table through the network either. For more information, the Oracle Docs have a nice section on Distributed Queries. This doc not only shows the DRIVING_SITE hint, but it explains how distributed queries work and how you can determine exactly what query is issued to the remote site.

HTH,
Brian Received on Thu Aug 24 2000 - 08:01:23 CDT