Cloud database: Microsoft SQL Azure and its application scenario

You can think of it as a cloud version of SQL Server, but you can't simply think of SQL Azure as a cloud-built SQL Server. SQL Azure is a relational database that can be deployed in the cloud to provide customers with a service based on a relational database at any time.

We can think of it as a cloud version of SQL Server, but it's not easy to think of SQL Azure as a cloud-built SQL Server. SQL Azure is a relational database that can be deployed in the cloud to provide customers with a service based on a relational database at any time. SQL Azure has a four-tier structure: The infrastructure layer, platform layer, service layer, and client layer, the first three layers of Microsoft Data Center, the client layer uses APIs or web-based clients to access data stored in the cloud. This article describes the main features, prices, scenarios for SQL Azure, the functional limitations of SQL Azure with T-SQL operations, and SQL Azure database.

Core features of SQL Azure:

SQL Azure is a key component of Microsoft's data platform, built on the basis of SQL Server technology, hosted by Microsoft based on cloud, offering scalable, multi-tenant, and highly available database services. SQL Azure Database helps simplify the provisioning and deployment of multiple databases without the need for developers to install, set up database software, or to patch or manage the database. The core functions of SQL Azure are: manageability, scalability, and programmability.

(1) Manageability

SQL Azure provides users with built-in high availability and fault tolerance without the need for actual customer management. SQL Azure supports the Data Application layer program (Data-tier applications), a database application-tier program is an entity that contains the database and instance objects required by almost one application, such as tables, views, stored procedures, logins, and so on. With the entity, originally independent landing, deployment, maintenance can be developed through the development of developers to integrate into a unified whole, such a whole is called the application package, so that the DBA can be a separate object as a database application layer of the program for deployment, monitoring and management. Currently supported data-tier applications have delete, deploy, extract, and register data-tier application packages.

(2) Scalability

A key advantage of cloud computing is that users can define their own solutions, using SQL Azure to meet the needs of users to create scalable solutions, which are manifested in:

Global scalability: Leased SQL Azure can be rented with a pay-as-you-go (pay-as-you-grow) strategy, renting smaller database capacity when the data is smaller with SQL Azure; When the size of the application database increases, consider expanding the database capacity. Because different database capacity costs and different capacity costs are inconsistent, specific costs can be referenced below for SQL Azure price. At present, there are 6 data centers available worldwide and you can choose which data center to use when expanding the database.

Multi-Tenant support: Supports software and services developed by independent software developers.

(3) Programmability

SQL Azure Database supports TDS and Transact-SQL (T-SQL), customers can use existing technologies to develop on t–sql, and can use relational data models that correspond to existing customer-owned database software. SQL Azure Database provides a cloud-based DBMS that consolidates existing toolset and provides a counterpart to customer-owned software. Specifically, programmability is manifested in three aspects:

Familiar client model: supports TDS and T-SQL, and can use Ado.net, ODBC, JDBC, and SQL Server driver for PHP.

Relational data Model: Users and administrators who use SQL Server are very familiar with how SQL Azure data is stored.

Data synchronization and offline support: You can use the Sync Framework for data synchronization and offline support.

SQL Azure Service Update 3, which is displayed on Tech ed by the SQL Azure Team, has been online and has completed some important features, such as support for the 50GB database. At the same time, 6 data centers are now available worldwide.

SQL Azure new Features:

(1) Update the database version and maximum capacity: SQL Azure Web version of the largest database maximum capacity is 5G, before this is 1G; The maximum data size for the SQL Azure Commercial Edition is 50G, previously 10G.

(2) Create or update a database: You can create or update a commercial database to 50G through T-SQL.

(3) Support query database version and maximum capacity: Use DATABASEPROPERTYEX (' database ', ' property ') to query the value of a database.

(4) Spatial data support-:sql Azure now provides support for geographic and geometric types, as well as for spatial data queries through T-SQL. This is an extremely important feature that allows Windows Azure platform to create space-and location-based applications.