SQL Server is a relational database management system developed by Microsoft. As a database server, it is a software product with the primary function of storing and retrieving data as requested by other software applications. The book describes the inner workings of the query optimizer and you can use this knowledge to write better queries and provide the query engine with all the required information it needs to produce efficient execution plans. You will also get tips for troubleshooting underperforming queries. Query performance topics such as In-Memory OLTP, the Query Store, and Intelligent Query Processing are covered as well.