Book Image

Professional Azure SQL Managed Database Administration - Third Edition

By : Ahmad Osama, Shashikant Shakya
Book Image

Professional Azure SQL Managed Database Administration - Third Edition

By: Ahmad Osama, Shashikant Shakya

Overview of this book

Despite being the cloud version of SQL Server, Azure SQL Database and Azure SQL Managed Instance stands out in various aspects when it comes to management, maintenance, and administration. Updated with the latest Azure features, Professional Azure SQL Managed Database Administration continues to be a comprehensive guide for becoming proficient in data management. The book begins by introducing you to the Azure SQL managed databases (Azure SQL Database and Azure SQL Managed Instance), explaining their architecture, and how they differ from an on-premises SQL server. You will then learn how to perform common tasks, such as migrating, backing up, and restoring a SQL Server database to an Azure database. As you progress, you will study how you can save costs and manage and scale multiple SQL databases using elastic pools. You will also implement a disaster recovery solution using standard and active geo-replication. Finally, you will explore the monitoring and tuning of databases, the key features of databases, and the phenomenon of app modernization. By the end of this book, you will have mastered the key aspects of an Azure SQL database and Azure SQL managed instance, including migration, backup restorations, performance optimization, high availability, and disaster recovery.
Table of Contents (14 chapters)
13
Index

The DTU model

In the DTU purchasing option, the amount of resources (CPUs, I/O, RAM, and storage) to be assigned to an SQL database in a particular service tier is calculated in DTUs.

DTUs guarantee that an SQL database will always have a certain amount of resources and a certain level of performance (offered under a particular DTU model) at any given point in time, independent of other SQL databases on the same SQL server or across Microsoft Azure.

The ratio for the aforementioned resources was calculated by Microsoft by running an Online Transaction Processing (OLTP) benchmark. One DTU roughly equates to 1 transaction/sec as per the benchmark.

The DTU purchasing model measures performance in DTUs instead of CPU and memory. Each DTU level and service tier provides predictable performance. The higher the DTU, the better the performance.

Note

The DTU purchasing model is not available with SQL Managed Instance.

In the DTU purchasing model, the compute and storage are bundled and priced together. For example, the 10 DTU standard service tier has a fixed storage capacity of 250 GB included within the DTU cost. Any additional storage is charged separately.