Previous knowledge of T-SQL querying is not required to get started on this book.

You can download the example code files for this book from your account at www.packt.com. If you purchased this book elsewhere, you can visit www.packt.com/support and register to have the files emailed directly to you.

You can download the code files by following these steps:

1. Log in or register at www.packt.com.
2. Select the SUPPORT tab.
3. Click on Code Downloads & Errata.
4. Enter the name of the book in the Search box and follow the onscreen instructions.

Once the file is downloaded, please make sure that you unzip or extract the folder using the latest version of:

• WinRAR/7-Zip for Windows
• Zipeg/iZip/UnRarX for Mac
• 7-Zip/PeaZip for Linux

The code bundle for the book is also hosted on GitHub at https://github.com/PacktPublishing/Learn-T-SQL-Querying. In case there's an update to the code, it will be updated on the existing GitHub repository.

The examples used throughout the book are designed for use on SQL Server 2017 and SQL Server 2019, but they should work on any version of SQL Server, 2012 or later. The Developer Edition of SQL Server is free for development environments and can be used to run all the code samples.

The sample databases AdventureWorks2016_EXT (referred to as AdventureWorks) and AdventureWorksDW2016_EXT (referred to as AdventureWorksDW) were both used for various scripts, and can be found on GitHub at https://github.com/Microsoft/sql-server-samples/releases/tag/adventureworks.

Some tools used in the book are not available with SQL Server. RML Utilities can be found at https://www.microsoft.com/download/details.aspx?id=4511, and Pssdiag/Sqldiag Manager can be found on GitHub at https://github.com/Microsoft/DiagManager.

We also have other code bundles from our rich catalog of books and videos available at https://github.com/PacktPublishing/. Check them out!

We also provide a PDF file that has color images of the screenshots/diagrams used in this book. You can download it here: http://www.packtpub.com/sites/default/files/downloads/9781789348811_ColorImages.pdf.

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, path names, dummy URLs, user input, and Twitter handles. Here is an example: "For example, if our table contains 1,000,000 rows, the calculation is SQRT(1000 * 1000000) = 31622."

A block of code is set as follows:

SELECT NationalIDNumber, JobTitle, MaritalStatus
INTO HumanResources.Employee2
FROM HumanResources.Employee;

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

[default]
exten => s,1,Dial(Zap/1|30)
exten => s,2,Voicemail(u100)
exten => s,102,Voicemail(b100)
exten => i,1,Voicemail(s0)

Bold: Indicates a new term, an important word, or words that you see onscreen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "For reference, the QueryTimeStats property for this query execution plan is in the following screenshot."