Databases Reference
In-Depth Information
Summary
This chapter explained how you can define the key of your indexes so that they are likely
to be considered for seek operations, which can improve the performance of your queries
by finding records more quickly. Predicates were analyzed in the contexts of both single
and multi-column indexes, and we also covered how to verify an execution plan to
validate that indexes were selected and properly used by SQL Server.
The Database Engine Tuning Advisor and the Missing Indexes feature, both introduced
with SQL Server 2005, were presented to show how the Query Optimizer itself can be
used to provide index tuning recommendations.
Finally, the
sys.dm_db_index_usage_stats
DMV was introduced, together with
its ability to provide valuable information regarding your non-clustered indexes usage.
While we didn't have time to discuss all the practicalities of using this DMV, we covered
enough for you to be able to easily find non-clustered indexes that are not being used by
your SQL Server instance.
