Learn T-SQL Querying

Troubleshoot query performance issues, identify anti-patterns in code, and write efficient T-SQL queries

Key Features

• Discover T-SQL functionalities and services that help you interact with relational databases
• Understand the roles, tasks and responsibilities of a T-SQL developer
• Explore solutions for carrying out database querying tasks, database administration, and troubleshooting

Book Description

Transact-SQL (T-SQL) is Microsoft’s proprietary extension to the SQL language that is used with Microsoft SQL Server and Azure SQL Database. This book will be a useful guide to learning the art of writing efficient T-SQL code in modern SQL Server versions, as well as the Azure SQL Database.

The book will get you started with query processing fundamentals to help you write powerful, performant T-SQL queries. You will then focus on query execution plans and learn how to leverage them for troubleshooting. In the later chapters, you will learn how to identify various T-SQL patterns and anti-patterns. This will help you analyze execution plans to gain insights into current performance, and determine whether or not a query is scalable. You will also learn to build diagnostic queries using dynamic management views (DMVs) and dynamic management functions (DMFs) to address various challenges in T-SQL execution. Next, you will study how to leverage the built-in tools of SQL Server to shorten the time taken to address query performance and scalability issues. In the concluding chapters, the book will guide you through implementing various features, such as Extended Events, Query Store, and Query Tuning Assistant using hands-on examples.

By the end of this book, you will have the skills to determine query performance bottlenecks, avoid pitfalls, and discover the anti-patterns in use.

Foreword by Conor Cunningham, Partner Architect – SQL Server and Azure SQL – Microsoft

What you will learn

• Use Query Store to understand and easily change query performance
• Recognize and eliminate bottlenecks that lead to slow performance
• Deploy quick fixes and long-term solutions to improve query performance
• Implement best practices to minimize performance risk using T-SQL
• Achieve optimal performance by ensuring careful query and index design
• Use the latest performance optimization features in SQL Server 2017 and SQL Server 2019
• Protect query performance during upgrades to newer versions of SQL Server

Who this book is for

This book is for database administrators, database developers, data analysts, data scientists, and T-SQL practitioners who want to get started with writing T-SQL code and troubleshooting query performance issues, through the help of practical examples. Previous knowledge of T-SQL querying is not required to get started on this book.

Table of Contents

1. Anatomy of a Query
2. Understanding Query Processing
3. Mechanics of the Query Optimizer
4. Exploring Query Execution Plans
5. Writing Elegant T-SQL Query
6. Easily Identified T-SQL Anti-Patterns
7. Discovering T-SQL Anti-Patterns in Depth
8. Building Diagnostic Queries Using DMVs and DMFs
9. Building xEvent Profiler Traces
10. Comparative Analysis of Query Plans
11. Tracking Query Performance History with the Query Store
12. Troubleshooting Live Queries
13. Managing Optimizer Changes With the Query Tuning Assistant