Chapter 11: An Introduction to Data Warehouses

Usually, when we read about high-performing applications in a SQL Server book or article, we assume they are only talking about transactional applications and, of course, online transaction processing (OLTP) databases. Although we have not mentioned data warehouses so far in this book, most of the content applies to both OLTP databases and data warehouse databases. The SQL Server query optimizer can automatically identify and optimize data warehouse queries without any required configuration, so the concepts explained in this book regarding query optimization, query operators, indexes, statistics, and more apply to data warehouses, too.

In this chapter, we will cover topics that are only specific to data warehouses. Additionally, describing what a data warehouse is provides us with the opportunity to define OLTP systems and what the differences between both are. We will describe how the query optimizer identifies data warehouse queries...