Book Image

Professional Azure SQL Database Administration - Second Edition

By : Ahmad Osama
Book Image

Professional Azure SQL Database Administration - Second Edition

By: Ahmad Osama

Overview of this book

Despite being the cloud version of SQL Server, Azure SQL Database differs in key ways when it comes to management, maintenance, and administration. This book shows you how to administer Azure SQL Database to fully benefit from its wide range of features and functionalities. Professional Azure SQL Database Administration begins by covering the architecture and explaining the difference between Azure SQL Database and the on-premise SQL Server to help you get comfortable with Azure SQL Database. You’ll perform common tasks such as migrating, backing up and restoring a SQL Server database to an Azure database. As you progress, you’ll understand how you can reduce costs, and manage and scale multiple SQL databases using elastic pools. You’ll also implement a disaster recovery solution using standard and active geo-replication. Whether it is learning different techniques to monitor and tune an Azure SQL Database or improving performance using in-memory technology, this book will enable you to make the most out of Azure SQL database features and functionality for data management solutions. By the end of this book, you’ll be well-versed with key aspects of an Azure SQL Database instance, such as migration, backup restorations, performance optimization, high availability, and disaster recovery.
Table of Contents (11 chapters)

Accelerated Database Recovery (ADR)

Accelerated Database Recovery, or ADR, is a new database recovery option that greatly increases the availability and decreases the time in scenarios such as crash recovery (database recovery in the event of a server/database crash), Always On availability group failover, and long-running transaction rollback (for example, a large bulk insert or an index rebuild rollback).

A SQL database consists of data and a transaction log file. A data file contains the table data. A transaction log file keeps track of all the changes made to the data and the schema; for example, if there is an insert in a table, the transaction log file contains the insert statement and whether the insert statement was committed or not.

To better understand ADR, let's first get an understanding of the current database recovery process.

Figure 8.4: The recovery phase without ADR

Note

Image taken from https://docs.microsoft.com/en-us/azure/sql-database/sql-database-accelerated...