You can download a free eBook Introducing Microsoft SQL Server 2008 R2 in PDF of XPS format from Microsoft.
Introducing Microsoft SQL Server 2008 R2 Contents at a Glance
PART I DATABASE ADMINISTRATION
CHAPTER 1 SQL Server 2008 R2 Editions and Enhancements
CHAPTER 2 Multi-Server Administration
CHAPTER 3 Data-Tier Applications
CHAPTER 4 High Availability and Virtualization Enhancements
CHAPTER 5 Consolidation and Monitoring
PART II BUSINESS INTELLIGENCE DEVELOPMENT
CHAPTER 6 Scalable Data Warehousing
CHAPTER 7 Master Data Services
CHAPTER 8 Complex Event Processing with StreamInsight
CHAPTER 9 Reporting Services Enhancements
CHAPTER 10 Self-Service Analysis with PowerPivot
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