Research Of Database Information Push Technology And The Implementation Of Its Model Based On Internet

With the improvement of Network and Database technology,information services based on the Intemetllntranet have been developingrapidly. It is an important method to provide dynamic information servicein the network through integrating Information Push-Pull technology withWeb Database technology. So, it is becoming a hot research area to pushdatabase information on the WWW.The traditional method for users to get information is usually theuser-driving pattern that is based on information-pull. But when users wantto get timely information service which means that users want to follow thedynamically changing information, this method would be impossible tosatisfy this demand on the capability of real-time. So we need technologiesby which dynamic data or changed data will be published automatically.Information-push technology is just this kind of technology, and its datarenewal mechanism is data-driving.In this dissertation, we discuss and analyze both demands and goals ofthe dynamic information service at some length. Integrating WebPush-Pull technology with mechanism of database trigger, and employingdatabase trigger, we propose a new and better database information pushmodel, the renewal mechanism of which is an asynchronous model ofdata-driving. Moreover we give a solution to this model. We also describethe conceptual model of this model system using OOA. We make itscollaboration diagrams and class diagrams using OOD. At the end of thisCdissertation, we design and implement an example of this model that is揝tock Information Real-time Publishing System?The DIPM system has some characteristics as follows. The first one isthat it is a system based on Internet and it has three-tire Client/Serverarchitecture. We employ trigger and extended store procedure of databasemanagement system to extend database server. And the function of thisextended module is to implement data pushing from data source on its owninitiative. In order to implement the application module of client, We try toextend browser via ActiveX or Java Applet. Application Server plays animportant role in the system, and its functions include communicating withdatabase server, dealing with the data request from clients; preserving thelinking information with clients, that will make the server to publish dataonly to related users.The DIPM based on Internet, which is proposed in this dissertation,provides a better solution and implementing technology for the applicationsthat need to publish dynamic information on WWW. The system 揝tockInformation Real-time Publishing System?has universality for theapplications of database information dynamically publishing, in themeaning time, this system validates the outcome from our academicresearch on the data renewal mechanism.