The DRIVING_SITE hint instructs the optimizer 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.
SELECT /*+ DRIVING_SITE(departments) */ *
FROM employees, departments@rsite
WHERE employees.department_id = departments.department_id;
If this query is executed without the hint, then rows from departments are sent to the local site, and the join is executed there. With the hint, the rows from employees are sent to the remote site, and the query is executed there and the result set is returned to the local site.