Exam objectives in this chapter:
Troubleshoot & Optimize
In Chapter 15, you learned internals about indexes and statistics in Microsoft SQL Server. In Chapter 14, you learned about the tools that help you analyze how a query was executed. In this chapter, you learn how SQL Server finds the data your query requests. SQL Server has different access methods for data retrieval. In addition, SQL Server implements different join algorithms. You learn about those and their strengths and weaknesses in this chapter.
SQL Server can reuse a query plan, even if the subsequent query is not the same. For example, the subsequent query can change a value for a search condition in the WHERE clause ...