[Azure services platform step by step-9th] windows azure storage Overview

ArticleDirectory

• Windows azure blob
• Windows azure table
• Windows azure queue
• Important differences between Windows azure table and SQL data services:

In the first article in this series, [azure services platform step by step-1st], the azure services platform contains four parts. Windows Azure is the basis for supporting the entire Microsoft cloud platform (azure services platform. In other words, Windows Azure is the operating system of the cloud platform. It provides the most basic and important services of the cloud platform.

Windows azure consists of two important parts:

1. Virtual computing service (Vm-based host is provided. I have demonstrated it in the previous article .)
2. Various data storage services. That is,Windows azure Storage.

Windows azure Storage enablesProgramMembers store any data they want to store. According to the concept of "cloud computing", once data is stored in the "Cloud", it will never be lost. programmers can obtain data of any size from any terminal and any place at any time. Windows azure storage continues to follow this idea.

Windows azure storage consists of three important parts:

1. Windows azure BLOB: Large Data Storage
2. Windows azure table: Stores Table data. Similar to data tables in relational databases, but different.
3. Windows azure queue: Provides the dispatch message service for asynchronous work. Similar to the message queue in windows.

Next we will introduce these three data services.

Windows azure blob

As I said just now, this ox x service is used to store large data. What kind of data is large? File! I don't know if you are the same as the author. When I first saw this service, the first reaction was to use it as a network hard disk. :)

The data model of Windows azure blob is very simple and won't be forgotten at a glance. We can really think of it as an infinitely large cloud disk. Its structure is as follows:

 

Let's not look at the "Block" section. Is it clear? Continue YY together: IfAccountThe hard disk,ContainerIt indicates different partitions (unfortunately, there is no folder concept in the partition ),BlobIs to partition different files in the root directory. So it means that in my hard drive named "Sally", there are two partitions: "pictures" and "Movies, the root directory of the "pictures" partition contains the "img001.jpg" "img002.jpg" files.

Where is the infinite cloud hard drive? How can we find it? It is also very simple, it still uses azure management, using rest to operate on it. The address is:

Http: // <account> .blob.core.windows.net/<container>/<blobname>

Example: http://maheshwar.blob.core.windows.net/livesearchimages/AcacusDesert_EN-US1025081982.jpg(This is an image. You can click the link to access it directly)

"Block. Since the rest method is used, it is through HTTP, it is obviously very difficult to directly transfer a large file, such as a 1g movie. Block exists to solve this problem. As long as you are in a good mood, you can split the movie into 1000 blocks of 1 Mbit/s for uploading. The block is transparent to the download process. The downloader does not know how many blocks the downloaded file is divided.

(In fact, I really use it for my own network hard drive, which is very convenient from the perspective of development and use. I will have the opportunity to sort it out later .)Code).

 

 

Windows azure table

This service is a favorite of many people.

Using vs200x to develop simple ASP. net Applications, you may have the following two important habits as many people do: Using relational databases (such as SQL Server); some tables in the database directly correspond to the entity classes in the program. You may use code generation tools, Orm tools, or write a three-tier architecture to map the relational database to objects. No. How much do you want to directly store entities in the database!

The Windows azure table service is used to solve this problem. It can directly store object classes and objects in the table structure. It makes too many people happy.

It is similar to tables in traditional relational databases, but it is quite different. First look at the structure:

Like what you think, it supports both LINQ and rest. The HTTP address is http: // <account> .table.core.windows.net.

This part contains a lot of content. In a few days, I will use the content of this section separately for a simple demo to explain how to use it.

Windows azure queue

Windows azure queue exists due to the service architecture of Windows azure-A Message Queue architecture.

In [azure services platform step by step-7th], do not use Windows azure as a virtual host-understand the Windows azure service architecture, in Windows azure Vm, how does one introduce the innovative concepts of Web role and worker role, thus breaking away from common virtual hosts and being promoted to "cloud hosts ":)

One of the most common applications of Windows azure queue is the message queue for communication between worker role and web role.

Here is another example. Web role is used to sell beef noodles at the front end, while worker role is used to cook beef noodles at the back end. Customers can only access the Web role shop assistant. It collects the requirements of different customers and keeps the requirements recorded first and then to a pile of paper and hand them to the chef worker roler. The chef worker role carries a mask and can't say anything. His job is to complete the recording tasks in order. Windows azure queue serves as the "Task paper.

After understanding the examples of "beef noodles", let's take a look at the reality of "cloud computing. Is it easy to understand?

 

 

Important differences between Windows azure table and SQL data services:

In actual development, both are the most common data storage services.

Montaque, a blog site netizen, and Comrade Lao Zhao, commented on the article [azure services platform step by step-8th] azure message board for development and deployment, and discussed windows azure table and SQL data services. different.

 

 

Windows azure table is designed to provide lightweight, fast, and low-cost large-scale data storage, including entities and properties. It is not a relational database, so it cannot provide methods similar to joins in SQL, nor manage foreign keys.

SQL data services is designed to provide rigorous relational data methods.

in the current azure version (feasure, the first version of the azure platform, is still not perfect), if developers require a large number of relational databases such as joins or foreign keys, you can select SQL data services. Otherwise, we recommend that you use Windows azure table for faster development.