FAQ: SQL Azure

In addition to the Windows Azure Platform FAQ, I’m posting answers to frequently asked questions about SQL Azure.

What are the main benefits of SQL Azure Database?
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Using SQL Azure provides many benefits. These include manageability, high availability, scalability, a familiar development model, and a relational data model.

• Controllability. SQL Azure offers the scale and functionality of a corporate data center with no administrative overhead, which is typically associated with local SQL Server instances. Thanks to this capability, organization self-management can provide data services to applications throughout an enterprise without increasing the burden on the central IT department and not distracting competent IT professionals from their core tasks to maintain the database application in one department. With SQL Azure, you can deploy data warehouses in minutes. This reduces the initial cost of data services due to the ability to deploy only the necessary resources. When you need to change or expand resources, you can easily adapt the cloud data storage to suit your needs.
• High availability. SQL Azure relies on proven Windows Server and SQL Server technologies and is flexible enough to handle any use cases and workloads. The service replicates data backups to multiple physical servers to ensure data availability and business continuity. In the event of a hardware failure, SQL Azure failover to ensure maximum application availability.
• Scalable. The main advantage of SQL Azure is the ease in scaling the solution. After initial partition configuration, the service is scaled as data grows. The pricing model, which provides for payment on the fact of use, allows you to pay only the actual space occupied, so the storage capacity can also be easily reduced if necessary.
• This is a new development model. When developers create local applications that use SQL Server, they use client libraries in which the interaction between the client and the server is done using the tabular data flow protocol (TDS). SQL Azure provides the same TDS interface as SQL Server, so you can use the same tools and libraries when creating client applications that work with data from SQL Azure. For more information about TDS, see Network Protocols and TDS Endpoints.
• Relational data model. Azure SQL System will seem very familiar to developers and administrators, since data is stored in SQL Azure just like in SQL Server using Transact-SQL. Conceptually similar to a local instance of SQL Server, SQL Azure Server is a logical group of databases acting as an authorization boundary.

In each SQL Azure server, you can create multiple databases with tables, views, stored procedures, indexes, and other familiar objects. This data model allows you to effectively use existing skills in relational database design and programming in Transact-SQL, and also simplifies the transfer of existing applications running on a local database to SQL Azure. For more information about Transact-SQL and SQL Azure connections, see Transact-SQL Support (SQL Azure Database) . Azure SQL Servers and databases are virtual objects and are not associated with physical servers or databases. By isolating from physical SQL injection, Azure allows you to focus on the database structure.


Is the existing SQL Server driver release for PHP compatible with SQL Azure?

Using the driver, developers can create PHP applications that support working with relational databases with SQL Server and SQL Azure. Some important changes have been made to improve performance, and new features have been added, including support for UTF-8 encoding and scrollable result sets.


How is physical administration implemented in SQL Azure Database?

Although SQL Azure plays an active role in managing physical database resources, you should not underestimate the enormous impact of a database administrator on administering SQL Azure database applications. With SQL Azure, database administrators manage schema creation, statistics collection, index tuning, query optimization, and security administration (logon, users, roles, and so on). For more information about security administration in SQL Azure, see Managing Login Data and Users in SQL Azure . Database administration in SQL Azure is the most different from SQL Server in terms of physical administration. SQL Azure automatically replicates all data for high availability. SQL Azure also manages load balancing and failover occurs in the event of a server failure. To achieve this level of physical administration, the management capabilities of SQL Azure physical resources were significantly limited. For example, you cannot specify a physical hard disk or a group of files in which a database or index will be located. Since the computer's file system is not available and all data is automatically replicated, SQL Server backup and restore commands do not apply to SQL Azure.


How are self-provisioning capabilities implemented in SQL Azure Database?

In preparation for deploying a local SQL Server system, the tasks of a database administrator or IT department may include installing and configuring the necessary hardware and software. When using SQL Azure, these tasks are performed by the SQL Azure preparation process. You can start preparing SQL Azure databases after you create a Windows Azure platform account. This account provides access to all services (Windows Azure, the service bus and access control of the Windows Azure platform, SQL Azure) and is used to configure and manage subscriptions. Each SQL Azure subscription is linked to a single SQL Azure server in the Microsoft data center. Azure SQL Server is an abstract concept that defines the grouping of databases. To ensure load balancing and high availability, databases linked to SQL Server Azure can be located on different physical computers in the Microsoft data center. For more information on preparation, see the Azure SQL Preparation Model .


What Transact-SQL features are supported?

Many SQL Server Transact-SQL statements have parameters that allow you to specify groups of files and physical file paths. These parameters are not supported in SQL Azure, as they relate to the physical configuration. In such cases, commands are considered partially supported. For more information about Transact-SQL support, see Support (SQL Azure Database) .


What functions and types are supported in SQL Azure Database?

SQL Azure does not support all the functions and data types that exist in SQL Server. Analytics, Replication, Reporting Services and Service Broker are not currently provided as services on the Windows Azure platform. Because SQL Azure performs physical administration, any instructions and parameters that attempt to directly manipulate physical resources (resource management, links to groups of files, and some DDL instructions of the physical server) will be blocked. In addition, you cannot set server parameters and SQL trace flags, or use the SQL Server Profiler and Database Tuning Advisor utilities. SQL Azure supports many SQL Server 2008 data types and does not support those types that are outdated for SQL Server 2008. For more information about SQL data types supported by SQL, see Data Types (SQL Azure Database) . For more information about legacy types of SQL Server 2008, see Legacy Database Engine Features in SQL Server 2008 .


How can I link data between a local SQL Server and SQL Azure Database?

The management tool provided for SQL Azure Data Sync will help you select the database and tables that you want to synchronize, and then create a SQL Server Agent service task to automatically synchronize data with SQL Azure on a schedule. This can be useful, for example, if you want to create a web application in Windows Azure and connect it to local data sources for creating reports and performing other actions.


What is SQL Azure Data Sync?

Microsoft SQL Azure Data Sync is a toolkit and runtime for data synchronization with SQL Azure. This technology allows you to implement two key scenarios that are currently unavailable in other cloud computing platforms: expanding the existing local infrastructure for working in the cloud and providing customers with support for offline (cached) mode. By linking local data with the cloud infrastructure, you can easily share information with mobile users, business partners, remote offices and corporate data sources, while taking advantage of new services in the cloud. This technology creates a bridge that provides interaction between local and remote applications. Using caching mode allows you to develop clients with improved performance due to reduced latency and increased availability. In addition, caching mode provides less network utilization and improved server scaling by reducing workload and more convenient work scheduling.


How do I get more information on accessing SQL Azure Data Sync?

The SQL Azure Data Sync component is available as a CTP version included in the downloadable Microsoft Sync Framework Power Pack for SQL Azure . For more general information about SQL Azure Data Sync, see http://www.microsoft.com/windowsazure/sqlazure/datasync . The CTP version of the Power Pack is not included in the CTP version of SQL Azure, and must be downloaded separately.


What is included in the Sync Framework Power Pack for SQL Azure Database?

The Azure Database Sync Framework Power Pack for SQL contains three key components: the Sync Framework Provider tool, configured for SQL Azure Database; management tool with which you can automatically synchronize local SQL Server databases with Azure SQL databases; and an add-in for Visual Studio that helps implement cached mode scripts in SQL Azure.


Who are the target audiences and which segments are covered?

The SQL Azure Database component is targeted at the following audience.

• Traditional independent software vendors developing bundled applications with single-instance multi-deployment service architecture support or specialized business applications for companies that require enterprise-level scalability, reliability, availability, and data protection.
• Independent suppliers of SaaS software products for retail customers, developing new web applications on the Windows Azure platform.
• Custom application developers (vendors / partners) developing departmental enterprise applications based on Windows Azure.

What scenarios will be implemented in the transition to a relational data model?

The SQL Azure Database component will focus on the following scenarios.

• Scalable web applications: small organizations, amateurs and new companies with web applications of any level that require a relational database management system. Bundled products and specialized business applications of independent software vendors: traditional independent SaaS software vendors and custom application developers who expand their products; batch and specialized software hosted in the cloud.
• Divisional applications: enterprises developing departmental and workgroup level applications.
• Data consolidation: companies using SQL Azure to consolidate multiple data sources in the cloud and provide secure access from various locations, PCs and devices.

How will Azure SQL products evolve to support larger, more complex applications?

In the initial release of SQL, Azure Database will provide features suitable for relational applications, including support for a single instance of multiple deployments that require high levels of scaling. Future editions of SQL Azure will implement advanced features such as partitioned queries and automatic partition creation.


As with the development of SQL Azure Database is planned to ensure the security, availability, reliability and quality of data?

The SQL Azure Database will continue to be built on the proven platform and architecture of SQL Server technology, which provides high reliability and availability, and also provides enterprise-level security features. Combining these capabilities, SQL Azure Database offers an enterprise-level service level agreement that includes built-in automated tools for high availability and resiliency.


How has the programming model for SQL Azure Database changed?

Previously, the SQL Azure Database component supported a flexible object-based data model. However, after receiving customer feedback, it became clear that a fully relational data model was required in the cloud. In SQL Azure, the transition was made from the ACE programming model to a relational data model with many familiar SQL Server programming concepts. Developers can use existing Transact-SQL code to access data in the cloud, as well as create and modify applications that use Transact-SQL code to interact with a fully relational cloud-based database service. In addition, they can easily provide REST and SOAP services for data using existing accessors, such as ADO.NET data services.




How does the Microsoft SQL Azure Database component relate to a traditional local relational SQL Server database?

The SQL Azure Database component is based on SQL Server database technologies used for mission-critical applications in enterprises and the Internet. Because SQL Server is an extensive data platform that can handle all the information from creation to archiving, our data platform provides a very wide range of options. The SQL Azure Database provides a large set of relational capabilities and extends them to the cloud level as services, providing convenient use by customers and partners via the Internet. In addition, SQL Azure Database offers built-in scalability, availability, and on-demand provision, among others. Despite the fact that SQL Azure Database in its first implementation provides very limited capabilities for managing a relational database compared to the SQL Server platform, Microsoft plans to significantly expand them over time. In the future, it is expected that features such as reporting, analytics, extraction, conversion and loading, as well as many others, will be available.


How does Microsoft differentiate between SQL Azure and SQL Server?

Unlike administering a local instance of SQL Server, SQL Azure separates logical administration from physical administration. Customers still manage databases, credentials, users, and roles, but Microsoft is administering physical hardware (hard drives, servers, and storage). With this approach, SQL Azure provides a large-scale database service with support for a single instance of multiple deployments that provides enterprise-class availability, scalability, security and self-service. Because Microsoft administers all the physical resources, SQL Azure and local SQL Server instances differ in terms of administration, provisioning, Transact-SQL support, programming model, and functions. For more information, see the SQL Azure and SQL Server Similarities and Differences document.


What is the difference between working with SQL Azure Database and working with a hosting provider using SQL Server?

The SQL Azure Database provides a highly available, scalable database service that supports single-instance multi-deployment service architecture hosted by Microsoft in the cloud. SQL Azure Database provides independent management and allows you to easily prepare and deploy multiple databases. Developers do not need to install, customize, fix software or manage it. High availability and fault tolerance are built into the database, and no physical administration of hardware, storage, or servers is required. SQL Azure Database supports Transact-SQL (T-SQL). Customers can apply existing development skills in T-SQL and the familiar relational database model for symmetry with existing local databases. The SQL Azure Database provides significant economic benefits, reducing development costs by leveraging existing tools and symmetry between on-premises and cloud databases. However, when using a hosted database, developers are required to install, configure, update, and apply patches to the operating system and database management software. In addition, hosted database solutions should provide high availability and fault tolerance, as well as provide the ability to manage multiple scalable databases.


Does a cloud-based solution to a reporting or analytics service?

In the near future, we plan to implement the ability to use SQL Azure as a data source for business intelligence solutions, including the introduction of analytics and reporting services. However, now when deploying with SQL Server 2008 R2, you can access SQL Azure from local reporting and analytics services projects.


Are synchronization services supported in SQL Azure?

Currently, the CTP version of Microsoft Sync Framework Power Pack for SQL Azure can be used to support such scripts.


How does a customer's application scale beyond the allotted size of a SQL Azure database?

SQL Azure customers can prepare an unlimited number of databases in accordance with the requirements of their applications. Data can be distributed across multiple databases with no size limit.


What will be the differences for customers when using Windows Azure and SQL Azure Database table storage?

The SQL Azure Database will provide a scalable distributed relational database service in the cloud that is used to store, process, and analyze structured, semi-structured, and unstructured data. Windows Azure table storage is non-relational, scalable, simple structured storage (ISAM) in the cloud. Since the SQL Azure Database will provide database service to applications developed on the Windows Azure platform, customers will be able to pool these services according to their needs.


Can customers use a combination of cloud and local databases with the same controls and programming languages?

Thanks to the support of a TSQL-based relational data model in SQL Azure (via TDS), customers can use existing tools, such as Microsoft Visual Studio and SQL Server Management Studio, that is, work with local SQL Server instances and cloud-based SQL Azure Database. Thus, customers can create applications that use a combination of local and cloud databases.


What is the place of partners in this cloud services model, in particular, vendors, independent software vendors, system integrators and developers?

Business partners will continue to create batch applications with support for the single-instance service architecture of multiple deployments or specialized business applications, as well as use SQL Azure Database with similar skills and tools as for local SQL Server instances. Partners can also expand existing SQL Azure business applications with minimal effort. Independent software vendors and partners can also develop and offer new Saas applications for retail customers based on SQL Azure and Windows Azure with single-instance multi-deployment application service architecture.


Will SQL Azure Database work with Windows Azure?

Yes. The SQL Azure Database provides a cloud relational database service for Windows Azure. Developers creating Windows Azure applications will be able to access SQL Azure according to their database requirements.



What development tools can developers use when building business applications for SQL Azure?

Developers will be able to use Visual Studio to create new applications and implement SQL Azure support in existing ones. When developing applications, they can also use controls, constructors, and ASP.NET tools. In the future, developers will receive web-based management tools for accessing and managing cloud data, as well as tools and documentation to support additional programming languages ​​in SQL Azure.


Based on what are prices determined for SQL Azure databases?

Azure SQL database fees are determined based on the number of databases created and the application consumed per day. Payment is carried out monthly.


I have local instances of Windows Server, SQL Server. Can I transfer them to Windows Azure, SQL Azure? How would this happen?

Not. At present, it is not possible to migrate existing local instances of Windows Server, SQL Server to Windows Azure, SQL Azure.


How will Windows Azure and SQL Azure service level agreements be combined with current Microsoft licensing agreements for local products?

The Windows Azure Service Level Agreement and SQL Azure Service Agreement do not depend on Microsoft license agreements for local products. The service level agreements for the Windows Azure platform provide a guarantee regarding the uptime of each month for the cloud services used, and if the specified time is not observed, a certain amount is deducted from the customer’s invoice.


Useful materials:

• Windows Azure Development Center
• E-book "Windows Azure - Microsoft cloud platform"