【正文】 ation presented to the user. Simple examples include highlighting a selection made by the user or filling a field on a form based on a user39。s selection from a pull down list. Another example is using the sound of a cash register to confirm that a product has been added to an electronic shopping cart. Completed orders should be acknowledged quickly. This may be done with an acknowledgment or fulfillment page. The amount of time it takes to generate and download this page, however, is a source of irritation for many emerce users. Users are quick to attribute meaning to events. A blank page, or what a user perceives to be a long time to receive an acknowledgment, may be interpreted as there must be something wrong with the order. If generating an acknowledgment may take longer than what may be reasonably expected by the user, then the design should include intermediate feedback to the user indicating the progress being made toward acknowledgment or fulfillment. Finally, feedback should not distract the user. Actions and reactions made by the web site should be meaningful. Feedback should not draw the user39。s attention away from the important tasks of gathering information, selecting products, and placing orders. 3. Project Design In order to design a web site, the relational database must be designed first. Conceptual design can be divided into two parts: The data model and the process model. The data model focuses on what data should be stored in the database while the process model deals with how the data is processed. To put this in the context of the relational database, the data model is used to design the relational tables. The process model is used to design the queries that will access and perform operations on those tables. 4. Implementation Technologies The objective of this project is to develop an online book store. When the user types in the URL of the Book Store in the address field of the browser, a Web Server is contacted to get the requested information. In the .NET Framework, IIS (Inter Information Service) acts as the Web Server. The sole task of a Web Server is to accept ining HTTP requests and to return the requested resource in an HTTP response. The first thing IIS does when a request es in is to decide how to handle the request. Its decision is based upon the requested file39。s extension. For example, if the requested file has the .asp extension, IIS will route the request to be handled by . If it has the extens ion of .aspx, .ascx, etc, it will route the request to be handled by Engine. Figure 21 Relation between IIS and The Engine then gets the requested file, and if necessary contacts the database through for the required file and then the information is sent back to the Client’s browser. Figure 21 shows how a client browser interacts with the Web server and how the Web server handles the request from client. is a programming framework built on the mon language runtime that can be used on a server to build powerful Web applications. has many advantages – both for programmers and for the end users because it is patible with the .NET Framework. This patibility allows the users to use the following features through : a) Powerful databasedriven functionality: allows programmers to develop web applications that interface with a database. The advantage of is that it is objectoriented and has many programming tools that allow for faster development and more functionality. b) Faster web applications: Two aspects of make it fast piled code and caching. In the code is piled into machine language before a visitor ever es to the website. Caching is the storage of information in memory for faster access in the future. allows programmers to set up pages or areas of pages that are monly reused to be cached for a set period of time to improve the performance of web applications. In addition, allows the caching of data from a database so the website is not slowed down by frequent visits to a database when the data does not change very often. c) Memory leak and crash protection: automatically recovers from memory leaks and errors to make sure that the website is always available to the visitors. also supports code written in more than 25 .NET languages (including , C, and ). This is achieved by the Common Language Runtime (CLR) piler that supports multiple languages. MySQL Database In this project, MySQL is used as the backend database. MySQL is an open source database management system. The features of MySQL are given below: MySQL is a relational database management system. A relational database stores information in different tables, rather than in one giant table. These tables can be referenced to each other, to access and maintain data easily. MySQL is open source database system. The database software can be used and modify by anyone according to their needs. It is fast, reliable and easy to use. To improve the performance, MySQL is multi threaded database engine. A multithreaded application performs many tasks at the same time as if multiple instances of that application were running simultaneously. In being multithreaded MySQL has many advantages. A separate thread handles each ining connection with an extra thread that is always running to manage the connections. Multiple clients can perform read operations simultaneously, but while writing, only hold up another client that needs access to the data being updated. Even though the threads share the same process space, they execute individually and because of this separation, multiprocessor machines can spread the thread across many CPUs as long as the host operating system supports multiple CPUs. Multithreading is the key feature to support MySQL’s performance design goals. It is t