views with db links

From: Bill Becker <beckerb_at_mfldclin.edu>
Date: Wed, 12 Sep 2001 10:21:34 -0700
Message-ID: <F001.0038BECC.20010912101525@fatcity.com>

Hello,

Oracle 8.1.6 on Solaris 2.7.

Can any one provide me with information or a link regarding performance of views across database links?

I am thinking of the case where instance A has a view defined as "SELECT FLD1,FLD2,... FROM TABLE_T1_at_DBLINK".

Consider the case when a view such as this is referenced within a sql statement that joins this view with other local tables and also contains some WHERE conditions which reference a field in TABLE_T1.
Are the entire contents of TABLE_T1 transferred across the network, then the joins and where conditions are processed within the local instance? Or is the WHERE condition applied in the remote instance, and only rows which satisfy the condition are returned across the network?

I was under the impression that the former was true. Did the behaviour change in some previous version?

Thanks to any responders.
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Author: Bill Becker
  INET: beckerb_at_mfldclin.edu

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