Book Image

Microsoft SQL Server 2012 Performance Tuning Cookbook

Book Image

Microsoft SQL Server 2012 Performance Tuning Cookbook

Overview of this book

As a DBA you must have encountered a slow running application on SQL Server, but there are various factors that could be affecting the performance. If you find yourself in this situation, don't wait, pick up this book and start working towards improving performance of your SQL Server 2012. SQL Server 2012 Performance Tuning Cookbook is divided into three major parts -- Performance Monitoring, Performance Tuning, and Performance Management--that are mandatory to deal with performance in any capacity. SQL Server 2012 Performance Tuning Cookbook offers a great way to manage performance with effective, concise, and practical recipes. You will learn how to diagnose performance issues, fix them, and take precaution to avoid common mistakes. Each recipe given in this book is an individual task that will address different performance aspects to take your SQL Server's Performance to a higher level.The first part of this book covers Monitoring with SQL Server Profiler, DTA, System statistical function, SPs with DBCC commands, Resource Monitor & Reliability, and Performance Monitor and Execution Plan. The second part of the book offers Execution Plan, Dynamic Management Views, and Dynamic Management Functions, SQL Server Cache and Stored Procedure Recompilations, Indexes, Important ways to write effective TSQL, Statistics, Table and Index Partitioning, Advanced Query tuning with Query Hints and Plan Guide, Dealing with Locking, Blocking and Deadlocking and Configuring SQL Server for optimization to boost performance.The third and final part gives you knowledge of performance management with help of Policy Based Management and Management with Resource Governor.
Table of Contents (28 chapters)
Microsoft SQL Server 2012 Performance Tuning Cookbook
Credits
About the Authors
Acknowledgement
Acknowledgement
About the Reviewers
www.PacktPub.com
Preface
Index

Increasing performance by covering index


Before discussing covering index further, it should be understood that a covering index is not a separate type of index that has a different internal structure and algorithm. It is just a technique that is used to boost up the performance of data retrieval for the table.

You may wonder If it is not a new type of index, why do we need to use it?

Run the same SELECT query that we ran earlier in the Increasing performance by creating non-clustered index section, which was creating the non-clustered index seek operation. But now, run this query with some more fields in the SELECT clause, may be like this:

--running the same query we ran earlier to see behavior after --Non-Clustered Index was created with just one column extra --in the SELECT clause
SELECT OrderDate,OrderID FROM ordDemo WHERE OrderDate='2011-11-28 20:29:00.000'
GO

The ordDemo table already had a non-clustered index on the OrderDate field, so if you run this query, it should meet the non...