Maximizing Query Optimizer with Query and Table Hints
Play Maximizing Query Optimizer with Query and Table Hints
Hints are a powerful mechanism to force SQL Server to use alternate query plans. More often than not, the query optimizer does a fantastic job in creating the most optimized query plan for data access, but there may be numerous occasions when you would like to use alternate query plans to boost performance. Hints can help you do that. But beware; if not used correctly, Hints may adversely affect performance so should be used with care. In this breakout session, we first alert the DBAs on using Hints as they need to be sure that there is indeed a problem with the query plan. Then we look at different types of Hints including Query & Table Hints. In query Hints, we look at Fast N Hints, Join Hints, Group Hints, and Union Hints amongst others. In the Table Hints context, we discuss Index Hints & Plan Hints amongst others. We give relevant demonstrations showing performance improvement as well as performance degradation if Hints are not used correctly. Various concepts on SQL Server query processing architecture are also explained wherever relevant, to ensure that the audience gets the most out of the session.