Font Size: a A A

The Research And Application Of Active Mechanism In Active Object-Oriented Database Systems

Posted on:2001-03-09Degree:DoctorType:Dissertation
Country:ChinaCandidate:Q Z LiFull Text:PDF
GTID:1118360185495638Subject:Computer application technology
Abstract/Summary:PDF Full Text Request
A lot of processes of large applications based on database, such as social insurance information system, are affected directly by the change of data. Such kinds of applications need the support of the active mechanism of database system. Active database system can react to the change of internal or external state without the interference of users. Active rules define such a behavior.In this paper we take the active object-oriented database experimental system SDAOODB as the main clue. With the background of the application of Social Insurance Information System we study the implementing the technique, theory and application of active database.We constructed the ECA rule model in object-oriented data model. We discussed the method event, time event and temporal logic. We also introduced an effective approach of implementing complex event - monitoring intervals. We studied the global rules and local rules and decided to adopt the global rule in our system.We introduced a new rule execute model and gave three different kinds of abort measures. So we could introduce nested transaction into the semantic of rule executing. Then a rule processing algorithm supporting rich semantic of rule processing was given.In this paper we also discussed the rule analysis theory. By defining trigger graph, active graph and de-active graph we gave a static rule analysis algorithm of deciding of the rule termination. This algorithm improved the veracity of decision of rule termination. We also proposed a dynamic local behavior analysis approach. It could decide whether the rule sets can be terminated or behavioral consistency in the processing of rules.We introduced an active object-oriented database experimental system SDAOODB and discussed the system architecture and the important technique of implementation. SDAOODB was the first active object-oriented database experimental system in our country.According to the need of applications we applied the active mechanism to the co-operative information system with the support of SDAOODB. In the research we...
Keywords/Search Tags:active database, ECA rules, termination, temporal logic, co-operative information system, association rule
PDF Full Text Request
Related items