Database architecture components and architecture Components

Database architecture components and architecture Components

1. Oracle's important position and extensive application in the company.

2. In the Oracle overview, the role of root is emphasized, that is, the overall Oracle architecture. If you have mastered it, you can master 40% of Oracle knowledge.

3. If the static file is not started in the database, it is the file of the operating system. After the static file is started, it is the database process.

4. Dynamic files are mainly the SGA shared area and some core processes.

5. the User process is mainly the client, while the Server process is mainly the Server process. The PGA of the Server process is not from the shared memory.

6. database files (static files) are mainly Configuration Parameter files, superuser files, data files, control files, and log files.

7. database instances (dynamic files) are mainly used to access the database, including the memory structure and background processes.

8. There are three ways to connect to the database instance, including 1) direct connection between the User and the Server on the same machine; 2) network connection between the User and the Server; 3) the browser and User are connected over the network, and the User and Server are also connected over the network, while the User is on the intermediate application Server layer.

9. The role of the Shared Pool in SGA is mainly: 1) Library cache (Database buffer) is mainly used to cache SQL statements, and 2) Data dictionary cache (Data dictionary Buffer) it is mainly used to cache tables and so on. The above two methods are used to improve the efficiency of database operations.

10. The function of the Data buffer cache in SGA is mainly used to cache blocks that are frequently used recently.

11. The PGA (Program Global Area) of the Server process is non-shared and can only be written by the Server process. The memory includes the sorting Area, Session information, and cursor status.

What is the relationship between databases, algorithms, data structures, and components?

I don't know about databases and components. I don't know about computers, but about communication.
But I still understand algorithms and data structures: Programs = data structures + algorithms.
For a real problem, you need to abstract it into a computer language description. This is the data structure, and how to program to solve the problem is the algorithm. For example, in reality, you need to solve the problem, which is the distance from home to location a and location B. Assume that it is 10 kilometers away from a and 5 kilometers away from B. Then the data structure you abstracted must be int a = 10; int B = 5;
The corresponding algorithm is a> B? B:;
 
Different architectures, components, components, frameworks, and Middleware

C/S Client/Server
B/S Browser/Server

The difference is actually quite big.
Find an article to show you. It's well written --

Today, the world's science and technology are developing rapidly, especially the Internet technologies represented by communications, computers, and networks. As the development and application of the computer Internet in various fields such as politics, economy, and life, as well as the rapid popularization of networks and the dependence of the whole society on networks, computer networks have become the economic foundation and lifeblood of the country, as a powerful motive force for social and economic development, it is becoming increasingly important. However, because mainstream technology R & D enterprises and users are constantly discussing the issues of "B/S" and "C/S" technologies, who are superior and inferior, who represent the development of technology trends, and so on, the use of "OA (office)" and "Case Management" software by procuratorates has become confusing. This article will discuss the development and application prospects of the two technologies for reference by peers.

1. What are C/S and B/S?

To understand the development and changes of "C/S" and "B/S" technologies, we must first clarify three issues.

First, what is the C/S structure.
The C/S (Client/Server) structure is a well-known Client and Server structure. It is a software system architecture. It can take full advantage of the advantages of both ends of the hardware environment, and assign tasks to the Client and Server, thus reducing the communication overhead of the system. Currently, most application software systems are structured in the form of Client/Server. As the current software application system is developing towards distributed Web applications, both Web applications and Client/Server applications can perform the same business processing, and different modules share logical components. Therefore, both internal and external users can access new and existing application systems, and new application systems can be extended through the logic in the existing application system. This is the current development direction of application systems.

Although the traditional C/S architecture adopts an open mode, it is only an open level for system development, in a specific application, either the Client or the Server also requires specific software support. Due to the failure to provide an open environment that users really expect, C/S-structured software needs to develop different versions of software for different operating system systems. In addition, the product is updated rapidly, it is difficult to adapt to the simultaneous use of LAN users with more than computers. The cost is high and the efficiency is low.

2. What is the B/S structure.
The Browser/Server structure is the Browser and Server structure. With the rise of Internet technology, it is a change or improved structure of the C/S structure. In this structure, the user's working interface is implemented through the WWW Browser. A few transaction logics are implemented on the Browser, but the main transaction logic is implemented on the Server, form the so-called three-tier structure. This greatly simplifies the Client Computer load, reduces the cost and workload of system maintenance and upgrade, and reduces the overall cost (TCO) of users ).

According to the current technology, it is relatively easy to grasp and cost relatively low to establish B/S network applications in LAN and use database applications in Internet/Intranet mode. It is a one-time development in place that enables different people to access different methods (such as LAN, WAN, Internet/Intranet) from different locations) it can effectively protect the data platform and manage access permissions, and the server database is secure. Especially after the emergence of cross-platform languages such as JAVA, the B/S architecture management software is more convenient, fast and efficient.

Third, manage mainstream software technologies.
The mainstream technology of management software technology is the same as that of management thought. It also experienced three stages of development. First, the interface technology from the DOS character interface of the century to the Windows graphical interface (or graphical user interface GUI), until Browse ...... the remaining full text>