Book Image

SQL Server Query Tuning and Optimization

By : Benjamin Nevarez
Book Image

SQL Server Query Tuning and Optimization

By: Benjamin Nevarez

Overview of this book

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. This book starts by describing the inner workings of the query optimizer, and will enable you to use this knowledge to write better queries and provide the query engine with all the information it needs to produce efficient execution plans. As you progress, you’ll get practical query optimization tips for troubleshooting underperforming queries. The book will also guide you through intelligent query processing and what is new in SQL Server 2022. Query performance topics such as the Query Store, In-Memory OLTP and columnstore indexes are covered as well. By the end of this book, you’ll be able to get the best possible performance for your queries and applications.
Table of Contents (14 chapters)

In-memory OLTP architecture

One of the main strategic decisions made during the Hekaton project was to build a new database engine fully integrated into SQL Server instead of creating a new, separate product as other vendors did. This gave users several advantages, such as enabling existing applications to run without code changes, and not needing to buy and learn about a separate product. As mentioned earlier, Hekaton can provide a several orders of magnitude performance increase based on the following:

  • Optimized tables and indexes for main memory data access: Hekaton tables and indexes are designed and optimized for memory. They are not stored as database pages, and they do not use a memory buffer pool either.
  • T-SQL modules compiled to native code: Stored procedures can be optimized by the SQL Server query optimizer, like any regular stored procedure, and then compiled into highly efficient machine code. When this happens, trigger and scalar user-defined functions can...