tailieunhanh - o'reilly database programming with JDBC and Java 2nd edition phần 5

Tham khảo tài liệu 'o'reilly database programming with jdbc and java 2nd edition phần 5', công nghệ thông tin, kỹ thuật lập trình phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | JDBC and Java 2nd edition Client server is often a generic umbrella term for any application architecture that divides processing among two or more processes often on two or more machines. Any database application is a client server application if it handles data storage and retrieval in the database process and data manipulation and presentation somewhere else. The server is the database engine that stores the data and the client is the process that gets or creates the data. The idea behind the client server architecture in a database application is to provide multiple users with access to the same data. Two-tier client server The simplest shape a client server architecture takes is called a two-tier architecture. In fact most client server architectures are two-tier. The term two-tier describes the way in which application processing can be divided in a client server application. A two-tier application ideally provides multiple workstations with a uniform presentation layer that communicates with a centralized data storage layer. The presentation layer is generally the client and the data storage layer is the server. Some exceptional environments such as the X Window System shuffle the roles of client and server. Most Internet applications email Telnet FTP gopher and even the Web are simple two-tier applications. Without providing a lot of data interpretation or processing these applications provide a simple interface to access information across the Internet. When most application programmers write their own client server applications they tend to follow this two-tier structure. Figure shows how two-tier systems give clients access to centralized data. If you use the Web as an example the web browser on the client side retrieves data stored at a web server. Figure . The two-tier client server architecture The architecture of a system depends on the application. For situations such as the display of simple web pages you do not need anything more .