Book Image

Microsoft SQL Server 2008 R2 Administration Cookbook

By : Satya Shyam K Jayanty
Book Image

Microsoft SQL Server 2008 R2 Administration Cookbook

By: Satya Shyam K Jayanty

Overview of this book

Table of Contents (19 chapters)
Microsoft SQL Server 2008 R2 Administration Cookbook
Credits
Foreword
About the Author
Acknowledgment
About the Reviewers
www.PacktPub.com
Preface
More DBA Manageability Best Practices

Designing sustainable locking methods to improve concurrency


Every time a query is executed, the standard SQL defines four types of actions to maintain the concurrent transactions. They are dirty reads, non-repeatable reads, phantom reads, and lost updates. By default, SQL Server is efficient enough to use default locking mechanism behavior to control the task completion for simultaneous transactions. The locking behavior controls access to database resources and imposes a certain level of transactional isolation levels. The different SQL Server isolation levels are: READ COMMITTED, READ UNCOMMITTED, REPEATABLE READ, SERIALIZABLE, and SNAPSHOT—which is a SQL Server-specific isolation level implementation. In this recipe, we will go through the required steps in designing sustainable locking methods to improve concurrency on the data platform. By default, SQL Server allows using table hints for locking in SELECT, MERGE, UPDATE, INSERT, and DELETE statements to override the isolation level...