DRIVING_SITE

The DRIVING_SITE hint instructs the CBO to execute the query at a different site than that selected by the database. This hint is useful if you are using distributed query optimization.

For example:

SELECT /*+ DRIVING_SITE(tab2) */  *  FROM tab1, tab2@remote   WHERE tab.id = tab2.id;

If this query is executed without the hint, then rows from tab1 are sent to the local site, and the join is executed there. With the hint, the rows from tab2 are sent to the remote site, and the query is executed there and the result set is returned to the local site.

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