"Azure Services Platform Step by step-2nd" Forget SQL Server 200x--introducing SQL Data Services (SDS)

In most cases, Web applications need to rely on another database server. This database service requires professional IT people to maintain. Before you deploy your application, you need to think too much: Does the data server have enough capacity? What about the performance, stability and security? There are too many unknown factors ...

According to the basic concept of cloud computing, to solve the above problems, we need to cloud-based data platform, that is, to put the services in the cloud, relying on a strong cloud operating system and platform hardware to deal with. That's right. SQL data Services (SDS) is such a "cloud" based on the platform.

What is SDS?

SDS is a powerful, Internet-facing database that provides robust, secure, and flexible data base services. SDS provides two standard interfaces for soap and rest, and is detached from traditional programming languages so that coder with any language can easily manipulate it.

Why use SDS?

Flexibility and scale,business-ready reliability and Security,developer agility

SDS status in Azure Services platform:

SDS is one of the four main modules of Azure, providing data services for applications in the sky and other azure services modules in the cloud.

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Data types supported by SDS

SDS supports string (string), Decimal (decimal), Boolean, DateTime, and Binary several basic data types, and also supports a BLOB (Binary SCM object) data type. Allows you to store content in any format.

Application Address:

http://go.microsoft.com/?linkid=9373222

Dev Portal

Http://portal.ex.azure.microsoft.com

Ace Model

Finally came to the point. Before using SDS, you must understand the SDS ACE (authority,container,entity) model. Authority is the highest level of the object. A authority contains multiple container, and a container contains multiple entity. The following figure

We can think of Authoriy as a database instance (SQL Server instance) in SQL Server. Container, then, is like multiple independent databases in an instance. And entity is the equivalent of a record. This analogy is only an intuitive concept, in fact, there is a difference between the ACE model and the relational database.

If you want to make an exact analogy, container can be equated to a separate database in the relational databases, or to a table. Entity is a data record yes, but entity is arbitrary and does not require a specific structure definition in a table, as in a relational database. As you can see, a container can contain a variety of entity with different structures.

For example, as shown in the previous illustration, we can create a authority called "food" that includes two container named "Fruit" and "vegetable". container["Fruit" includes 3 entities, namely "Apple1", "Apple2", "pear1". Note, here we assume that the pentagram represents pear and the triangle represents Apple. In this way, the container["fruit" includes two types of three entity. Similarly, in the container["vegetable"], we assume that the circle is cabbage cabbage, square is the tomato tomato, we have "tomato1", "Tomato2", "Cabbage1" three entity, They are also of two different types.

Oh, the traditional Instance-database-tabale-row model is very different? It doesn't matter, just remember the basic structure now, in the next section, you will have a chance to play with them.

Programming model

Each authority corresponds to a specific URI. For example, a authority called food, its HTTP address is HTTPS://FOOD.DATA.DATABASE.WINDOWS.NET/V1, can be opened directly in the browser (in the browser zhogn1 directly open, Equivalent to executing HTTP GET method)

With the authority URI, you will find that the URI of container and entity is easily found. The format is as follows:

Https://food.data.database.windows.net/v1/<container-id>

such as https://food.data.database.windows.net/v1/fruit/

Https://food.data.database.windows.net/v1/<container-id>/<entity-id>

such as Https://food.data.database.windows.net/v1/fruit/apple1

The SDS programming model, CRUD, plainly is HTTP operations on these URIs. The following table is a map of HTTP verb to SDS twist

Well, that's the end of the section. : In the next section, I'll use a gadget to play through all the features of the SDS.