Book Image

SQL Server 2017 Developer???s Guide

Book Image

SQL Server 2017 Developer???s Guide

Overview of this book

Microsoft SQL Server 2017 is a milestone in Microsoft's data platform timeline, as it brings in the power of R and Python for machine learning and containerization-based deployment on Windows and Linux. This book prepares you for advanced topics by starting with a quick introduction to SQL Server 2017's new features. Then, it introduces you to enhancements in the Transact-SQL language and new database engine capabilities before switching to a different technology: JSON support. You will take a look at the security enhancements and temporal tables. Furthermore, the book focuses on implementing advanced topics, including Query Store, columnstore indexes, and In-Memory OLTP. Toward the end of the book, you'll be introduced to R and how to use the R language with Transact-SQL for data exploration and analysis. You'll also learn to integrate Python code into SQL Server and graph database implementations as well as the deployment options on Linux and SQL Server in containers for development and testing. By the end of this book, you will be armed to design efficient, high-performance database applications without any hassle.
Table of Contents (25 chapters)
Title Page
Copyright and Credits
Dedication
Packt Upsell
Contributors
Preface
Free Chapter
1
Introduction to SQL Server 2017
Index

System-versioned temporal tables in SQL Server 2017


SQL Server 2016 introduces support for system-versioned temporal tables. Unfortunately, application-time tables are not implemented neither in this version, nor in SQL Server 2017. System-versioned temporal tables bring built-in support for providing information about data stored in the table at any point in time rather than only the data that is correct at the current moment in time. They are implemented according to the specifications in the ANSI SQL:2011 standard with a few extensions.

How temporal tables work in SQL Server 2017

A system-versioned temporal table is implemented in SQL Server 2017 as a pair of tables: the current table containing the actual data, and the history table where only historical entries are stored. There are many limitations for both current and history tables. Here are limitations and considerations that you must take into account for the current table of a system-versioned temporal table:

  • It must have a primary...