How is SQL Azure of the next generation cloud database refined?

It is well known that cloud OS Windows Azure and Cloud Database SQL Azure play a very important architectural role in Microsoft's cloud computing strategy. Among them, Windows Azure mainly includes three parts, one is the computing service of Operation application, the other is data storage service, the third is the controller (Fabric Controller) that manages and allocates resources dynamically based on cloud platform. And the database plays an important role in the entire Microsoft cloud strategy, especially for cloud database SQL Azure.

In other words, SQL Azure is a relational cloud database that can provide customer data applications at any time. SQL Azure is built on a technical build based on SQL Server 2008, with Windows Azure as the base platform, with the features of Windows Azure. Also, SQL Azure is a cloud storage service that is dispersed across many of the entity infrastructure (physical infrastucture) and many virtual servers within it, which provides network-type application data storage services. and SQL Azure is serviced by multiple servers in the cloud, and the servers that provide services for each connection may be different, thus ensuring the high availability of cloud storage.

Below, the editor counts six reasons why the enterprise chooses database SQL Azure in the cloud from aspects of manageability, high availability, scalability, familiar development patterns, and relational data models for SQL Azure.

Reason one, self-management

SQL Azure provides the size and capabilities of an enterprise-class data center, eliminating the time cost of managing local SQL Server instances on a day-to-day basis. The ability to manage independently allows the enterprise to not increase the support load of the local IT department, to maintain departmental database applications, and to provide data services to the application throughout the enterprise. With SQL Azure, you can prepare your database store in a very short time and subscribe to the storage services you need to reduce the initial investment in your deployment and operational database. When requirements change, you can also quickly reduce or increase database services to meet demand.

Reason two, high availability

SQL Azure is built on proven Windows Server and SQL Server technologies and is resilient enough to handle all load changes. Services replicate multiple redundant copies on multiple physical servers to maintain data availability and business continuity. If one piece of hardware fails, the automatic failover provided by SQL Azure ensures application availability.

Reason three, scalability

One of the key advantages of SQL Azure is the ability to easily scale your solution. As data grows, the database also needs to be expanded vertically and horizontally. Vertical scaling tends to have an upper limit, while horizontal scaling has no actual limitations. The usual way to expand horizontally is to divide data. After the data has been split, the service expands as the data grows. A pricing model that pays for your use (Pay as Go) ensures that you pay for the storage you use, so you can reduce the size of the service anytime you don't need it.

Reason four, familiar development pattern

When developers create local applications that use SQL Server, they use client libraries, such as Add.net, ODBC. They use the TDS protocol to communicate between the client and the server. SQL Azure provides a consistent TDs interface with SQL Server, so you can use the same tools and class libraries to build your application to access data in SQL Azure. (For more TDS related information, see Network Protocols and TDS endpoints (receptacle Protocols and TDS endpoints) on the MSDN Web site.) ）

SQL Azure Service Architecture (image from Network)

Note: Data is transmitted between the client and the database server, and the packet is formatted. Known as the TDS (Tabular Data Stream) in SQL Server, TDS is an application layer protocol that is used to exchange data between the database server and the client. Initially, the agreement was developed in 1984 by Sybase Company's relational database engine for their products Sybase SQL Server, which was later used by Microsoft in Microsoft SQL Server.

Reason v. Relational data model

SQL Azure should be easy for developers and administrators, because SQL Azure uses a relational data model that is stored on SQL Azure and stored on SQL Server, conceptually similar to a local SQL Server instance. A SQL Azure server is a logical combination of a set of databases and is an independent authorization unit.

Within each SQL Azure server, you can create multiple databases, each of which can have multiple tables, views, stored procedures, indexes, and other familiar database objects. The data model can well reuse existing relational database design, Transact-SQL programming skills and experience, and simplify the process of migrating existing local database applications to SQL Azure.

SQL Azure servers and databases are logical objects and do not correspond to physical servers and databases. Through user-physical isolation, SQL Azure enables users to dedicate time to database design and business logic.

Reason six, flexible database version

The SQL Azure database provides two different versions: the Web version and the commercial version. Two versions provide scalability, automated high-availability, and automatic provisioning.

The web version of the database service works for small Web applications. This version of the database supports a maximum of 1GB and 5GB of capacity.

The commercial version of the database service applies to business applications developed by software Enterprises. This version of the database supports the maximum 10GB to 50GB capacity.

When you create a database in the cloud, users can define the version and maximum capacity of the database. With T-SQL, a user can use the CREATE DATABASE statement and specify the maximum capacity (MAXSIZE) of the database. If the amount of data increases and exceeds the maximum capacity of the database, the user receives an error message. The user can also use ALTER DATABASE to enlarge the maximum capacity of the database through T-SQL.