Problem solve Get help with specific problems with your technologies, process and projects.

Using the DRIVING_SITE hint

Oracle expert Brian Peasland explains how the DRIVING_SITE hint can help an optimizer to run a remote query on either the local or the remote system.

When a join operation comprises elements bound by a dblink (typically "select ... from a,[email protected],[email protected] where .."), can one oblige the instances concerned to carry out the algebraic operations "projection" and "selection" on their side (not to bring back all on the client side)? Is it possible to use (locally) the distant tables statistics? Also, are there differences in Oracle versions (9.2, 10 and 11)?
You can influence the optimizer to run the remote query on either the local or the remote system with the DRIVING_SITE hint. See the white paper titled "Tuning Distbributed Queried and the DRIVING_SITE Hint" on my web site, Peasland Oracle Consulting. This paper will show you how to use this hint.

Dig Deeper on Oracle database administration